Luminescence, structure and insight on the inversion degree from normal to inverse spinel in a ZnAl(2−x)Fex3+O4 system | Boletín de la Sociedad Española de Cerámica y Vidrio

array:24 ["pii" => "S0366317520300297" "issn" => "03663175" "doi" => "10.1016/j.bsecv.2020.02.005" "estado" => "S300" "fechaPublicacion" => "2021-05-01" "aid" => "211" "copyright" => "SECV" "copyrightAnyo" => "2020" "documento" => "article" "crossmark" => 1 "licencia" => "http://creativecommons.org/licenses/by-nc-nd/4.0/" "subdocumento" => "fla" "cita" => "Bol Soc Esp Ceram Vidr. 2021;60:147-62" "abierto" => array:3 [ "ES" => true "ES2" => true "LATM" => true ] "gratuito" => true "lecturas" => array:1 [ "total" => 0 ] "itemSiguiente" => array:19 [ "pii" => "S0366317520300200" "issn" => "03663175" "doi" => "10.1016/j.bsecv.2020.01.012" "estado" => "S300" "fechaPublicacion" => "2021-05-01" "aid" => "202" "copyright" => "SECV" "documento" => "article" "crossmark" => 1 "licencia" => "http://creativecommons.org/licenses/by-nc-nd/4.0/" "subdocumento" => "fla" "cita" => "Bol Soc Esp Ceram Vidr. 2021;60:163-74" "abierto" => array:3 [ "ES" => true "ES2" => true "LATM" => true ] "gratuito" => true "lecturas" => array:1 [ "total" => 0 ] "en" => array:13 [ "idiomaDefecto" => true "cabecera" => "Original" "titulo" => "Use of mechanical activation to obtain Mg(OH)2 from olivine mineral for CO2 capture" "tienePdf" => "en" "tieneTextoCompleto" => "en" "tieneResumen" => array:2 [ 0 => "en" 1 => "es" ] "paginas" => array:1 [ 0 => array:2 [ "paginaInicial" => "163" "paginaFinal" => "174" ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Uso de la activación mecánica para obtener Mg(OH)2 del mineral de olivino para la captura de CO2" ] ] "contieneResumen" => array:2 [ "en" => true "es" => true ] "contieneTextoCompleto" => array:1 [ "en" => true ] "contienePdf" => array:1 [ "en" => true ] "resumenGrafico" => array:2 [ "original" => 0 "multimedia" => array:7 [ "identificador" => "fig0080" "etiqueta" => "Fig. 16" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr16.jpeg" "Alto" => 1179 "Ancho" => 1591 "Tamanyo" => 123158 ] ] "descripcion" => array:1 [ "en" => "TGA and DTA curves of hydromagnesite after CO2 absorption at 200°C/24h." ] ] ] "autores" => array:1 [ 0 => array:2 [ "autoresLista" => "Claudia Maribel García-Hernández, Jorge López-Cuevas, Carlos Alberto Gutiérrez-Chavarría, Alfredo Flores-Valdés" "autores" => array:4 [ 0 => array:2 [ "nombre" => "Claudia Maribel" "apellidos" => "García-Hernández" ] 1 => array:2 [ "nombre" => "Jorge" "apellidos" => "López-Cuevas" ] 2 => array:2 [ "nombre" => "Carlos Alberto" "apellidos" => "Gutiérrez-Chavarría" ] 3 => array:2 [ "nombre" => "Alfredo" "apellidos" => "Flores-Valdés" ] ] ] ] ] "idiomaDefecto" => "en" "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S0366317520300200?idApp=UINPBA00004N" "url" => "/03663175/0000006000000003/v2_202106110717/S0366317520300200/v2_202106110717/en/main.assets" ] "itemAnterior" => array:19 [ "pii" => "S0366317520300339" "issn" => "03663175" "doi" => "10.1016/j.bsecv.2020.03.006" "estado" => "S300" "fechaPublicacion" => "2021-05-01" "aid" => "215" "copyright" => "SECV" "documento" => "article" "crossmark" => 1 "licencia" => "http://creativecommons.org/licenses/by-nc-nd/4.0/" "subdocumento" => "fla" "cita" => "Bol Soc Esp Ceram Vidr. 2021;60:138-46" "abierto" => array:3 [ "ES" => true "ES2" => true "LATM" => true ] "gratuito" => true "lecturas" => array:1 [ "total" => 0 ] "en" => array:13 [ "idiomaDefecto" => true "cabecera" => "Original" "titulo" => "Tuning Ca3Co4O9 thermal and transport properties by TiC nanoparticles addition" "tienePdf" => "en" "tieneTextoCompleto" => "en" "tieneResumen" => array:2 [ 0 => "en" 1 => "es" ] "paginas" => array:1 [ 0 => array:2 [ "paginaInicial" => "138" "paginaFinal" => "146" ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Ajuste de propiedades térmicas y eléctricas del Ca3Co4O9 por medio de adición de nanopartículas de TiC" ] ] "contieneResumen" => array:2 [ "en" => true "es" => true ] "contieneTextoCompleto" => array:1 [ "en" => true ] "contienePdf" => array:1 [ "en" => true ] "resumenGrafico" => array:2 [ "original" => 0 "multimedia" => array:7 [ "identificador" => "fig0015" "etiqueta" => "Fig. 3" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr3.jpeg" "Alto" => 1688 "Ancho" => 1625 "Tamanyo" => 169746 ] ] "descripcion" => array:1 [ "en" => "Enlarged view of the (002) diffraction peak in the Ca3Co4O9+x wt.% TiC samples; x=0.00 (a); 0.25 (b); 0.50 (c); 0.75 (d); and 1.0 (e)." ] ] ] "autores" => array:1 [ 0 => array:2 [ "autoresLista" => "H. Amaveda, O.J. Dura, M. Mora, M.A. Torres, G. Guelou, M.A. Madre, S. Marinel, A. Sotelo" "autores" => array:8 [ 0 => array:2 [ "nombre" => "H." "apellidos" => "Amaveda" ] 1 => array:2 [ "nombre" => "O.J." "apellidos" => "Dura" ] 2 => array:2 [ "nombre" => "M." "apellidos" => "Mora" ] 3 => array:2 [ "nombre" => "M.A." "apellidos" => "Torres" ] 4 => array:2 [ "nombre" => "G." "apellidos" => "Guelou" ] 5 => array:2 [ "nombre" => "M.A." "apellidos" => "Madre" ] 6 => array:2 [ "nombre" => "S." "apellidos" => "Marinel" ] 7 => array:2 [ "nombre" => "A." "apellidos" => "Sotelo" ] ] ] ] ] "idiomaDefecto" => "en" "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S0366317520300339?idApp=UINPBA00004N" "url" => "/03663175/0000006000000003/v2_202106110717/S0366317520300339/v2_202106110717/en/main.assets" ] "en" => array:20 [ "idiomaDefecto" => true "cabecera" => "Original" "titulo" => "Luminescence, structure and insight on the inversion degree from normal to inverse spinel in a ZnAl(2−x)Fex3+O4 system" "tieneTextoCompleto" => true "paginas" => array:1 [ 0 => array:2 [ "paginaInicial" => "147" "paginaFinal" => "162" ] ] "autores" => array:1 [ 0 => array:4 [ "autoresLista" => "Simon N. Ogugua, Odireleng M. Ntwaeaborwa, Hendrik C. Swart" "autores" => array:3 [ 0 => array:4 [ "nombre" => "Simon N." "apellidos" => "Ogugua" "email" => array:1 [ 0 => "Oguason@yahoo.com" ] "referencia" => array:2 [ 0 => array:2 [ "etiqueta" => "a" "identificador" => "aff0005" ] 1 => array:2 [ "etiqueta" => "*" "identificador" => "cor0005" ] ] ] 1 => array:3 [ "nombre" => "Odireleng M." "apellidos" => "Ntwaeaborwa" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "b" "identificador" => "aff0010" ] ] ] 2 => array:3 [ "nombre" => "Hendrik C." "apellidos" => "Swart" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "a" "identificador" => "aff0005" ] ] ] ] "afiliaciones" => array:2 [ 0 => array:3 [ "entidad" => "Department of Physics, University of the Free State, Bloemfontein ZA-9300, South Africa" "etiqueta" => "a" "identificador" => "aff0005" ] 1 => array:3 [ "entidad" => "School of Physics, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa" "etiqueta" => "b" "identificador" => "aff0010" ] ] "correspondencia" => array:1 [ 0 => array:3 [ "identificador" => "cor0005" "etiqueta" => "⁎" "correspondencia" => "Corresponding author." ] ] ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Luminiscencia, estructura e información sobre el grado de inversión de la espinela normal a la inversa en un sistema ZnAl(2−x)Fex3+O4" ] ] "resumenGrafico" => array:2 [ "original" => 0 "multimedia" => array:7 [ "identificador" => "fig0080" "etiqueta" => "Fig. 16" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr16.jpeg" "Alto" => 950 "Ancho" => 1341 "Tamanyo" => 116270 ] ] "descripcion" => array:1 [ "en" => "The PL emission spectra of (a) Zn(1−x)Fex3+Al2O4 and (b) ZnAl(2−x)Fex3+O4 for x=0.05, excited at 235nm." ] ] ] "textoCompleto" => "IntroductionA spinel unit cell contains 8 face-centered cubics (FCC) cells. Spinels are made up of an anion, occupying the FCC lattice points, forming octahedral (oct) and tetrahedral (tet) sites with two central metal ions, usually divalent and trivalent ions, respectively <a class="elsevierStyleCrossRef" href="#bib0445">[1]</a>. They are represented by a general formula AB2O4, where “A2+” is a divalent metal ion occupying the tet sites and “B3+” is a trivalent metal ion occupying the oct sites. Spinels belong to the F−d3m space group. Each unit cell contains 32 oxygen (O2−) atoms, with 8 “A2+” atoms and 16 “B3+” atoms. Depending on the distribution of the “A2+” and “B3+” ions in the unit cell, spinels are divided into normal and inverse. Normal spinels have a cubic closed-packed (ccp) structure with more “B3+” ions than “A2+” ions. The “A2+” ions occupying 1/8 of the tet sites and the “B3+” ions occupying ½ of the oct sites. Atomic arrangement in the inverse spinel is such that the whole A2+ ions and ½ of the B3+ ions occupy the oct sites, while the other ½ of the B3+ ions occupy the tet sites. Furthermore, there is an intermediate structural arrangement described by the formula (A1−yBy) [Ay/2B1−y/2]2O4 with the terms in parentheses and square brackets denoting the tet and oct sites, respectively. y is called the inversion degree, and its values range from 0, for normal structure, and 1, for inverse structure, and 2/3 for random ion distribution <a class="elsevierStyleCrossRef" href="#bib0450">[2]</a>.ZnAl2O4 belong to the spinel group known as the spinel-aluminate family. It is naturally available in a mineral called gahnite. ZnAl2O4 has almost normal spinel structure <a class="elsevierStyleCrossRef" href="#bib0455">[3]</a>. Like other normal spinel structures, ZnAl2O4 has cubic symmetry, Fd−3m space group and 8 formulae per unit cell <a class="elsevierStyleCrossRef" href="#bib0460">[4]</a>. The O2− ions form a closed-packed structure with 64 tet and 32 oct interstices per unit cell. As mentions previously, only 1/8 of the tet voids are occupied by Zn2+, while the Al3+ occupies half (½) of the oct voids. Generally, in one FCC unit cell, the effectual number of ions occupying the lattice point is 4 <a class="elsevierStyleCrossRef" href="#bib0465">[5]</a>. Concurrently, the effectual number of ions in the oct and tet voids are 4 and 8, respectively. Hence, in ZnAl2O4, Zn2+ ions occupy 8×1/8×8=8 tet sites of Td symmetry and Al3+ ions occupy 8×½×4=16 oct sites of D3d symmetry; while O2− ions occupy 8×4=32 sites of C3v symmetry <a class="elsevierStyleCrossRef" href="#bib0470">[6]</a>. <a class="elsevierStyleCrossRef" href="#fig0005">Fig. 1</a>(a) shows the schematic illustrations of the ZnAl2O4 unit cell with only five oct and seven tet sites. <a class="elsevierStyleCrossRef" href="#fig0005">Fig. 1</a>(b) and (c) shows the coordinates of the tet site and the oct site, respectively.<elsevierMultimedia ident="fig0005"></elsevierMultimedia>Transition-metals have edge over rare earth elements from an economic point of view <a class="elsevierStyleCrossRefs" href="#bib0475">[7,8]</a>. They have the capacity to give broadband emission in the visible and infrared regions <a class="elsevierStyleCrossRefs" href="#bib0450">[2,8–11]</a>, which leads to their aptness in tunable radiation sources in optical devices <a class="elsevierStyleCrossRefs" href="#bib0500">[12–15]</a>. In particular, Fe3+ doped matrices are of special importance due to its ability to emit in lower and higher wavelength ends of the visible spectrum when doped into tet and oct sites, respectively <a class="elsevierStyleCrossRefs" href="#bib0450">[2,16]</a>.Electrical neutrality can be maintained in a solid material through charge balance. Charge imbalance can lead to the formation of charge defects in the host lattice and hence creates non-radiative luminescence centers in the material <a class="elsevierStyleCrossRef" href="#bib0525">[17]</a>. The presence of non-radiative transitions, largely, can reduce the luminescence emission intensity and hence luminescence efficiency of a phosphor <a class="elsevierStyleCrossRef" href="#bib0530">[18]</a>. Different charge compensation models have been used in enhancing the luminescence of phosphors <a class="elsevierStyleCrossRefs" href="#bib0525">[17,19–21]</a>. The first model involves a divalent ion replaced by a trivalent ion. In this model, the host has to capture one O2 from the air to balance the charge differently. The second model involves replacement of three divalent ions by two trivalent ions, with the charge balance contributed by the extra vacancy provided by the excess divalent ion. In the third model, two divalent ions are replaced by one trivalent ion and one alkali metal ion (monovalent ion) is used to balance the charge. The relative intensities of the phosphors prepared using the second and third model was found to be twice that of the phosphor prepared using the first <a class="elsevierStyleCrossRef" href="#bib0540">[20]</a>.In different instances, researchers have reported ZnAl2O4 doped trivalent metal ions (Dy3+, Eu3+, Td3+, Fe3+, Fe3+, Ce3+), while substituting the trivalent metal ions in the place of Zn2+, without considering the consequences of charge imbalance on the luminescence properties <a class="elsevierStyleCrossRefs" href="#bib0445">[1,2,22,23]</a>. Hence, in this report, the luminescent properties of Zn(1−x)Fex3+Al2O4 and ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) matrices were studied. In the Zn(1−x)Fex3+Al2O4 system, one Zn2+ ion was substituted by one Fe3+ ion. Because of the charge imbalance in this system, the host has to trap ambient O2 to compensate for charge. In the ZnAl(2−x)Fex3+O4 system, one Al3+ ion was substituted by one Fe3+ ion ensuring direct charge balance system.ExperimentalSynthesisZnAl2O4 doped with different mol% of Fe3+ were synthesized using the Pechini synthesis method. The starting materials were zinc nitrate hexahydrate (Zn(NO3)2·6H2O), aluminum nitrate nonahydrate (Al(NO3)3·9H2O), iron nitrate nonahydrate (Fe(NO3)3·9H2O), tartaric acid (C4H6O6) and nitric acid. For the undoped sample, 3.245 and 8.184g mass of Zn(NO3)2·6H2O, and Al(NO3)3·9H2O, respectively, were dissolved in 10mL of nitric acid in a glass beaker, and it was labeled solution “A”. 6.549g of C4H6O6 was dissolved in 40mL of distilled water in a different glass beaker, and it was labeled solution “B”. Solutions “A” and “B” were stirred using different magnetic stirrers on a hot plate set at 150°C for about 20min until transparent solutions were obtained. The two transparent solutions were combined and the mixture was stirred at 150°C temperature for about 2h until the liquid evaporated. Prior to the end of the reaction, an evolution of a brownish fume was observed. Still, inside the glass beaker, the sample was dried at 80°C for 10h to get white powder. After grinding the sample with an agate mortar and a pestle, it was calcined at 600°C for 3h. For the doped samples, different amount of Fe(NO3)3·9H2O (0.0008, 0.0022, 0.0044, 0.0071g) were added to substitute Al(NO3)3·9H2O and create matrices of the form ZnAl(2−x)Fex3+O4 (x=0.01, 0.025, 0.05, 0.08). A matrix of the form Zn(1−x)Fex3+Al2O4 (x=0.05) was also created by substituting Zn(NO3)2·6H2O with 0.0022g of Fe(NO3)3·9H2O, the aforementioned procedure was repeated.CharacterizationA Bruker D8 Advanced X-ray diffractometer (XRD) using monochromatic Cu Kα (λ=1.5406Å) X-ray as radiation source was used to characterize the structure of the materials. The morphologies and the elemental analysis of the powders were studied using a JEOL JSM-7800F field emission scanning electron microscope (FE-SEM) fitted with Oxford X-MaxN 80 energy-dispersive X-ray spectrometer (EDS). A PHI 5000 Versaprobe-scanning ESCA microprobe X-ray photoelectron spectroscopy (XPS) was used to obtain the chemical and electronic state data of the samples. A PerkinElmer Lambda 950 UV-Vis spectrometer was used to record the ultraviolet–visible (UV–vis) diffuse reflectance data. An FLS980 fluorescence spectrometer-(Edinburgh Instruments) fitted with a 450W Xenon lamp as a source of steady-state excitation was used to collect the PL data.Results and discussion<a class="elsevierStyleCrossRef" href="#fig0010">Fig. 2</a>(a) shows the XRD patterns of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) compared to the standard phase of ZnAl2O4, referenced in JCPDS file no. 82-1043. All the samples show identical patterns as the standard data of spinel ZnAl2O4, indicating that they crystallized in a single-phase cubic symmetry and Fd3m space group of ZnAl2O4. <a class="elsevierStyleCrossRef" href="#fig0010">Fig. 2</a>(b) shows the XRD pattern in the diffraction angle range of 36.6–37.6 (2θ), depicting the (311) diffraction plane. It is seen from <a class="elsevierStyleCrossRef" href="#fig0010">Fig. 2</a>(b) that the (311) peak shifted to the lower diffraction angle relative to the undoped sample with increasing Fe3+<a class="elsevierStyleCrossRefs" href="#bib0560">[24,25]</a>. The shift may be due to distortions in the ZnAl2O4 host lattices since the dopant (Fe3+) have larger ionic radius than Al3+ (see <a class="elsevierStyleCrossRef" href="#tbl0005">Table 1</a>) <a class="elsevierStyleCrossRef" href="#bib0570">[26]</a>.<elsevierMultimedia ident="fig0010"></elsevierMultimedia><elsevierMultimedia ident="tbl0005"></elsevierMultimedia>The average crystallite size (L) of the phosphors is related to its lattice strain (ɛ) by Williamson–Hall equation <a class="elsevierStyleCrossRefs" href="#bib0575">[27,28]</a> given by Eq. <a class="elsevierStyleCrossRef" href="#eq0005">(1)</a>:<elsevierMultimedia ident="eq0005"></elsevierMultimedia>where βh k l is the full width at half maximum (FWHM) of each diffraction peak, λ is the wavelength of the X-ray (0.15406nm) used for measurement, θ is the Bragg angle and κ is a constant related to the crystallite shape, taken as 0.9 for spherical crystals. From a graph of βh k l Cos θ versus 4 Sin θ, the crystallite size and the strain were determined from the y-intercept and the slope of the graph, respectively. The estimated values of the crystallite sizes and the strain for the undoped sample and for the samples doped with different concentration of Fe3+ are listed in <a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a>. It is evident from <a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a> that the crystallite size and the strain increased with the Fe3+ concentration.<elsevierMultimedia ident="tbl0010"></elsevierMultimedia>The lattice constant (lattice parameter) defines the physical dimension of a unit cells in a crystal lattice. For a cubic crystal, the lattice parameter (a) (the length of the edges of the unit cells), the interplanar spacing (d) (the perpendicular distance between successive parallel planes of the atoms in a crystal), and the Miller indices (hkl) (notations for planes in crystal lattices) are related by Eq. <a class="elsevierStyleCrossRef" href="#eq0010">(2)</a><a class="elsevierStyleCrossRef" href="#bib0585">[29]</a>:<elsevierMultimedia ident="eq0010"></elsevierMultimedia>The d is related to the X-ray wavelength (λ) and the diffraction angle (θ) by Eq. <a class="elsevierStyleCrossRef" href="#eq0010">(2)</a>:<elsevierMultimedia ident="eq0015"></elsevierMultimedia>Hence, the values of ‘a’ and ‘b’ can be calculated using Eqs. <a class="elsevierStyleCrossRefs" href="#eq0010">(2) and (3)</a> and the value of the ‘θ’ can be determined from the XRD data. The calculated values of a are listed in <a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a>. In spite of having cubic symmetry, spinels structures cannot be explained entirely by the lattice parameters (a). An additional dimensionless parameter (oxygen parameter, u) is used to define the slight distortion that occur in the FCC oxygen lattice for a complete description of the spinel lattice points <a class="elsevierStyleCrossRef" href="#bib0590">[30]</a>. For an undistorted oxygen lattice in spinels, u=0.250 if the origin of the unit cell is taken at the center of symmetry. The oxygen parameter, u, the lattice parameter, a, and the cation-anion distance in the tet and oct sites (Rtet and Roct, respectively) are related by Eqs. <a class="elsevierStyleCrossRefs" href="#eq0020">(4) and (5)</a><a class="elsevierStyleCrossRef" href="#bib0595">[31]</a>:<elsevierMultimedia ident="eq0020"></elsevierMultimedia><elsevierMultimedia ident="eq0025"></elsevierMultimedia>Inasmuch as a and u give information about the lattice positions, for an absolute representation of the spinel lattice, the proportion of cations occupying the different sites should be determined. The distribution parameter (y) is the degree of inversion and it defines the fraction of the trivalent ions occupying the tet sites. Hence, it varies from 0 to 1 for totally normal and inverse spinels, respectively. Eqs. <a class="elsevierStyleCrossRefs" href="#eq0020">(4) and (5)</a> are valid for only “perfect” normal or inverse spinels. The distribution of cations in the sites of normal spinels such as gahnite, ZnAl2O4, is represented by formula {1}:<elsevierMultimedia ident="eq0030"></elsevierMultimedia>with the divalent cations, Zn2+, occupying the tet sites (tet) and the trivalent cations, Al3+, occupying the oct sites <a class="elsevierStyleCrossRef" href="#bib0590">[30]</a>. Doping ZnAl2O4 with different concentrations Fe3+ will result in the formation of ZnAl(2−x)Fex3+O4 composite, resulting in the creation of some Fe–O–Fe bonds in the matrix. This may lead to the formation of some spinel ferrites (ZnFe2O4), which have similar structure as ZnAl2O4, within the matrix <a class="elsevierStyleCrossRef" href="#bib0600">[32]</a>. Furthermore, some of the Fe3+ can be reduced to Fe2+ as confirmed by the XPS result (<a class="elsevierStyleCrossRef" href="#fig0040">Fig. 8</a>(a)) via the equation Fe3++e−→Fe2+<a class="elsevierStyleCrossRefs" href="#bib0605">[33,34]</a>, resulting in the formation of iron oxides, such as Fe3O4 (magnetite) within the ZnAl(2−x)Fex3+O4 matrix. The existence of Fe2+ in the matrices indicates that ZnAl(2−x)Fex3+O4 does not crystallize in a pure normal spinel phase, rather it crystallized as a mixture of normal and inverse spinel, since Fe3O4 crystallizes in an inverse spinel. In inverse spinels, such as magnetite, Fe3O4, the distribution of the cations in the sites are represented by formula {2}:<elsevierMultimedia ident="eq0035"></elsevierMultimedia>with one-half of the trivalent cations, Fe3+, occupying the tet sites, while both the divalent cations, Fe2+, and the remaining Fe3+ share the oct sites <a class="elsevierStyleCrossRef" href="#bib0590">[30]</a>.Furthermore, a solid solution formed by ZnAl(2−x)Fex3+O4 and Fe3O4 is represented by formula {3}, by combining formula {1} and {2}, bearing in mind that Zn2+ and Fe3+ prefer the tet site in ZnAl2O4 and Fe3O4, respectively.<elsevierMultimedia ident="eq0040"></elsevierMultimedia>In formula {3}, we assumed that ZnAl2O4 and ZnFe2O4 have similar structure (normal spinels), and hence the combination of the two compounds should not have substantial effect on the spinel type. Formula {3} will form a solid solution with properties lying between normal and inverse spinels. In the case where more than one cation occupies the same site, the bond length is determined by finding the effective bond length – i.e. the average of the individual cationic bond length <a class="elsevierStyleCrossRef" href="#bib0590">[30]</a>. Therefore, for a cation, i with bond length Ri and mole fraction zi on the tet site the effective bond length is defined by Eq. <a class="elsevierStyleCrossRef" href="#eq0045">(6)</a>:<elsevierMultimedia ident="eq0045"></elsevierMultimedia>also, a similar expression is used for Roct. The bond lengths were determined by combining Eqs. <a class="elsevierStyleCrossRefs" href="#eq0020">(4)–(6)</a>, and substituting the values of u and a for the end members, ZnAl2O4 and Re3O4 from <a class="elsevierStyleCrossRef" href="#tbl0015">Table 3</a>. Also keeping in mind that the tet sites are completely occupied by Zn2+ in ZnAl2O4 and by Fe3+ in Fe3O4. The resulting values of the bond lengths are listed in <a class="elsevierStyleCrossRef" href="#tbl0015">Table 3</a>.<elsevierMultimedia ident="tbl0015"></elsevierMultimedia>It is seen from formula {3} that Zn2+ and Al3+ only occupy the tet and oct sites, respectively. Hence, the change of the crystal structure with the composition of Fe will depend on the distribution of the Fe3+ and Fe2+ cations in the available tet and oct sites, respectively. In additions, a varies linearly with the dopant concentration (x) (see <a class="elsevierStyleCrossRef" href="#fig0015">Fig. 3</a>), hence, the distribution of Fe2+ and Fe3+ varies linearly within the crystal. For y fraction of Fe3+ and Fe2+ occupying the tet and oct sites, respectively, Rtet and Roct are given by Eqs. <a class="elsevierStyleCrossRefs" href="#eq0050">(7) and (8)</a>, respectively, for the sample with x=0.01.<elsevierMultimedia ident="eq0050"></elsevierMultimedia><elsevierMultimedia ident="eq0055"></elsevierMultimedia><elsevierMultimedia ident="fig0015"></elsevierMultimedia>By equating Eqs. <a class="elsevierStyleCrossRefs" href="#eq0020">(4) and (5)</a> to Eqs. <a class="elsevierStyleCrossRefs" href="#eq0050">(7) and (8)</a>, respectively, and substituting the values of the bond lengths R and the lattice parameters a, the values of y and u can be determined. Following the same procedure, the value of y and u is determined for the rest of the samples, and the results are presented in <a class="elsevierStyleCrossRef" href="#tbl0020">Table 4</a>.<elsevierMultimedia ident="tbl0020"></elsevierMultimedia>The FE-SEM images of the undoped and 0.08mol% Fe3+ doped ZnAl2O4 are shown in <a class="elsevierStyleCrossRef" href="#fig0020">Fig. 4</a>(a) and (b), respectively. Fe3+ doping showed no significant effect on the morphologies of the phosphors. Both images show agglomerated spherical grains with what appear to be distinctive grain boundaries and varying grain sizes. The average diameters of the particles were taken randomly using the line tool in the ImageJ software, version IJ 1.46r <a class="elsevierStyleCrossRef" href="#bib0625">[37]</a>. The size distribution curves were obtained from the FE-SEM images, with estimated mean grain sizes of 112±5 and 118±6nm for the undoped and 0.08mol% Fe3+ doped ZnAl2O4 as shown in the insets of <a class="elsevierStyleCrossRef" href="#fig0020">Fig. 4</a>(a) and (b), respectively. The estimated grain sizes for the samples doped with other mol% of Fe3+ (x=0.01, 0.025, 0.05, 0.08) were 115, 117, 124 and 128nm, respectively. Compared to the crystallite size obtained from the XRD data, the grain size is much bigger. Wang, Li, and Tamrakar et al. have reported similar result <a class="elsevierStyleCrossRefs" href="#bib0630">[38–40]</a>. The grain size and the crystallite size of the particles are different owing to the formation of polycrystalline aggregates <a class="elsevierStyleCrossRef" href="#bib0645">[41]</a>, which appears as one particle in SEM, especially in amorphous materials <a class="elsevierStyleCrossRef" href="#bib0635">[39]</a>.<elsevierMultimedia ident="fig0020"></elsevierMultimedia>The EDS was used for the semiquantitative and the elemental composition analysis of ZnAl(2−x)Fex3+O4, x=0–0.08 phosphors and the spectra for x=0 and 0.08 are shown in <a class="elsevierStyleCrossRef" href="#fig0025">Fig. 5</a>(a) and (b), respectively. The elements (Zn, Al and O) expected in the compounds are present in the EDS spectra of the all samples. In the doped samples, 0.1at.% of Fe was observed in the samples with high concentration of Fe (x=0.05 and 0.08). The same amount of Fe was measured in the EDS spectra of the samples, even though they contain different concentration of Fe. This could be due to the detection limit of the technique ∼ 0.1% <a class="elsevierStyleCrossRef" href="#bib0650">[42]</a>. This imply that measured values of 0.05 and 0.14% should be approximated to 0.1%. The presence of carbon (C) in the EDS spectra could be from environmental hydrocarbon and/or carbon tape on which the samples were mounted. The insets of <a class="elsevierStyleCrossRef" href="#fig0025">Fig. 5</a>(a) and (b) are the measured elemental concentration at.% of all the elements present in the ZnAl(2−x)Fex3+O4, x=0 and 0.08 samples, and <a class="elsevierStyleCrossRef" href="#tbl0025">Table 5</a> presents the elemental concentration at.% present in the ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05 and 0.08) phosphors.<elsevierMultimedia ident="fig0025"></elsevierMultimedia><elsevierMultimedia ident="tbl0025"></elsevierMultimedia>XPS is an in situ technique where a specimen is irradiated with X-rays leading to ionization, and ejection of photoelectrons from the core-shell and the kinetic energies distribution are measured using electron energy analyzer and a photoelectron spectrum can thus be recorded <a class="elsevierStyleCrossRef" href="#bib0655">[43]</a>. XPS was used to determine the electronic and chemical bonding state from the surface of the samples. The XPS spectra were fitted using the PHI MULTIPAK software, version 8.2C <a class="elsevierStyleCrossRef" href="#bib0660">[44]</a>.<a class="elsevierStyleCrossRef" href="#fig0030">Fig. 6</a>(a)–(d) shows, respectively, the fitted high-resolution O 1s XPS spectra of ZnAl(2−x)Fex3+O4 for x=0, 0.01, 0.05 and 0.08. The spectra show two peaks for the undoped ZnAl2O4 sample (x=0, <a class="elsevierStyleCrossRef" href="#fig0030">Fig. 6</a>(a)), but exhibits three peaks for the Fe3+ doped samples (x=0.01, 0.05 and 0.08, <a class="elsevierStyleCrossRef" href="#fig0030">Fig. 6</a>(b–d)). The two components centered at 531.3 and 533.0eV in <a class="elsevierStyleCrossRef" href="#fig0030">Fig. 6</a>(a) are ascribed to the metal–oxygen (M–O) bonds <a class="elsevierStyleCrossRef" href="#bib0665">[45]</a> and O–H bonds from water molecules absorbed from the environmental moisture, respectively <a class="elsevierStyleCrossRefs" href="#bib0670">[46,47]</a>. The additional peak centered at 534.1eV for x=0.01 and 534.0eV for x=0.05 and 0.08 is ascribed to the Fe–OH bonds <a class="elsevierStyleCrossRef" href="#bib0680">[48]</a>. This indicates that Fe ions were incorporated successfully into the ZnAl2O4 host. The peaks belonging to M–O and O–H bonds in <a class="elsevierStyleCrossRef" href="#fig0030">Fig. 6</a>(a)–(d) shifted slightly to lower binding energy after Fe3+ doping.<elsevierMultimedia ident="fig0030"></elsevierMultimedia>The Al 2p high-resolution XPS spectra for ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.05 and 0.08), are shown, respectively, in <a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>(a)–(d). The two peaks centered at 74.2 and 75.1eV in <a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>(a) were ascribed to Al ions occupying the tet and oct sites by Tshabalala et al. <a class="elsevierStyleCrossRef" href="#bib0685">[49]</a>, in comparison with a report on Y3Al5O12 (YAG) by Pawlak et al. <a class="elsevierStyleCrossRef" href="#bib0690">[50]</a>. However, YAG has an entirely different structure from ZnAl2O4. In the ZnAl2O4 system, the tet sites is occupied by only Zn2+ ions and the oct sites is occupied by only Al3+ ions <a class="elsevierStyleCrossRef" href="#bib0590">[30]</a> as shown in <a class="elsevierStyleCrossRef" href="#fig0005">Fig. 1</a> and by formula {1}, while in YAG, Al3+ ions can occupy both tet and oct sites <a class="elsevierStyleCrossRef" href="#bib0690">[50]</a>. Furthermore, similar XPS peaks have been observed in doped Al2O3 samples and where assigned to M–Al–O or M–Al (M=metal ion) <a class="elsevierStyleCrossRefs" href="#bib0695">[51–55]</a>. For instance, in the La1−xAlxO3 system, it was assigned to La–Al–O by Fei et al. <a class="elsevierStyleCrossRef" href="#bib0695">[51]</a>, while in the Ru/La(x)–Al2O3 system, it was assigned to Al–La by Chung et al. <a class="elsevierStyleCrossRef" href="#bib0700">[52]</a>. Another point that is worth noting is that the peak around 76.0eV in <a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>(b)–(d) (assigned to tet Al by Tshabalala et al. <a class="elsevierStyleCrossRef" href="#bib0685">[49]</a>) appears at higher binding energy compare to the other peak (around 74eV) which they assigned to oct Al. However, it is expected that the higher the number of oxygen coordinating a metal ion, the higher the binding energy since the binding energy increase with electronegativity <a class="elsevierStyleCrossRef" href="#bib0720">[56]</a>. Therefore, we believe that the photoelectron peaks at the lower binding energy (74.2eV) and higher binding energy (75.1eV) in <a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>(a) are due to the Al–O in AlO6 (Al3+ ions in the oct sites) <a class="elsevierStyleCrossRef" href="#bib0685">[49]</a> and AL–OH <a class="elsevierStyleCrossRef" href="#bib0725">[57]</a> in AlO6, respectively. For the Fe3+ doped samples, an additional photoelectron peak appeared at the higher binding energy centered at 76.0eV for the sample doped with 0.01mol% of Fe3+ (x=0.01) and at 76.1eV for (x=0.05 and 0.08) as shown in <a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>(b)–(d). It is also evident from <a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>(b)–(d) that the peaks from Al–O and AL–OH shifted to lower binding energies at higher Fe3+ doping concentration. The additional peaks observed at 76.0eV in <a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>(b) and at 76.1eV in <a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>(c) and (d), are assigned to the Al–O–Fe at the oct sites, in the ZnAl(2−x)Fex3+O4 system <a class="elsevierStyleCrossRefs" href="#bib0695">[51,52]</a>. It is interesting to observe that the intensity of the photoelectron peaks from the Al–O–Fe increased with increasing Fe3+ concentration, but the intensities of the photoelectron peaks from Al–O decreased. This shows that more Al–O–Fe are created in the ZnAl(2−x)Fex3+O4 system with increasing Fe3+ concentration. The peaks assigned to Al–O–Fe in <a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>(b)–(d) appears at higher binding energy with respect to the other peaks assigned to Al–O and AL–OH, because Fe (1.83) have higher electronegativity than Al (1.61) <a class="elsevierStyleCrossRef" href="#bib0730">[58]</a>.<elsevierMultimedia ident="fig0035"></elsevierMultimedia>The deconvoluted Zn 2p XPS spectra for the ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.05 and 0.08) are shown in <a class="elsevierStyleCrossRef" href="#fig0040">Fig. 8</a>(a)–(d), respectively. For the undoped ZnAl2O4 shown in <a class="elsevierStyleCrossRef" href="#fig0040">Fig. 8</a>(a), a double peak from the Zn 2p core-level were observed at 1021.9 and 1045.0eV and are assigned to the Zn 2p3/2 and Zn 2p1/2<a class="elsevierStyleCrossRef" href="#bib0735">[59]</a> from the Zn occupying the tet site (ZnO4) in ZnAl2O4, respectively. For the Fe3+ doped samples (<a class="elsevierStyleCrossRef" href="#fig0040">Fig. 8</a>(b–d)), a new photoelectron peak was observed at the higher binding energy with respect to the Zn 2p3/2 and Zn 2p1/2 peaks which shifted to high binding energy values with increasing Fe3+ ions concentration. These peaks are centered at 1022.7 and 1045.9eV, 1023.4 and 1046.5eV, 1024.4 and 1047.6eV for ZnAl(2−x)Fex3+O4 (x=0.01, 0.05 and 0.08), respectively, as shown in <a class="elsevierStyleCrossRef" href="#fig0040">Fig. 8</a>(b)–(d) and they are assigned to Zn–O–Fe in the tet sites. Yngman et al. have reported a similar result in Zn doped GaAs <a class="elsevierStyleCrossRef" href="#bib0740">[60]</a>, Li et al. in Cu doped ZnS <a class="elsevierStyleCrossRef" href="#bib0745">[61]</a> and Beltrán et al. in carbon doped ZnO <a class="elsevierStyleCrossRef" href="#bib0750">[62]</a>.<elsevierMultimedia ident="fig0040"></elsevierMultimedia>The peaks assigned to Zn–O–Fe in <a class="elsevierStyleCrossRef" href="#fig0040">Fig. 8</a>(b)–(d) appeared at higher binding energy values with respect to the peaks assigned to Zn in ZnO4, because Fe (1.83) have higher electronegativity than Zn (1.65) <a class="elsevierStyleCrossRef" href="#bib0730">[58]</a>. However, Zhang et al. <a class="elsevierStyleCrossRefs" href="#bib0735">[59,63]</a> attributed the photoelectron peaks at the lower binding energies in Zn 2p3/2 and Zn 2p1/2 to Zn2+ ions occupying tet sites and the photoelectron peaks at higher binding energies in Zn 2p3/2 and Zn 2p1/2 to Zn2+ occupying the oct sites in ZnAl2O4:Cr3+ system. However, they did not show the XPS spectrum for the undoped ZnAl2O4. In <a class="elsevierStyleCrossRef" href="#fig0040">Fig. 8</a>(a), the XPS spectrum for the undoped ZnAl2O4 did not show any sign of the two photoelectron peaks sitting at the higher binding energies with respect to the Zn 2p3/2 and Zn 2p1/2 peaks. This suggests that the two peaks sitting at higher binding energies to Zn 2p3/2 and Zn 2p1/2 peaks in <a class="elsevierStyleCrossRef" href="#fig0040">Fig. 8</a>(a) are associated with Fe ions. The intensities of the photoelectron peaks from the Zn–O–Fe in <a class="elsevierStyleCrossRef" href="#fig0040">Fig. 8</a>(b)–(d) increased as the Fe3+ ions concentration increased in ZnAl(2−x)Fex3+O4 system. However, unlike the Al 2p peaks, there was no significant change in the Zn 2p peaks intensities. The formation of Zn–O–Fe and Al–O–Fe bonds in the ZnAl2O4: Fe3+ matrices suggest the possibility of existence of tet and oct Fe in these matrices.The Fe XPS peaks could not be detected in the samples doped with concentration of up to 0.08mol%, hence we prepared another sample doped with 4mol% of Fe3+. <a class="elsevierStyleCrossRef" href="#fig0045">Fig. 9</a>(a) shows the deconvoluted XPS spectrum for Fe 2p peak. The spectrum consists of the shake-up peaks (satellite peaks) and the Fe 2p3/2 and Fe 2p1/2 components. Each component of the Fe 2p peak consist of two Fe ion peaks signifying the different oxidation states of Fe ion (Fe2+ and Fe3+). The shape-up peaks were located relatively at higher binding energies of 713.0eV and 725.4eV with respect to the 2p3/2 and 2p1/2 components, respectively <a class="elsevierStyleCrossRefs" href="#bib0760">[64,65]</a>. The photoelectron peaks at the lower binding energies (704.6 and 717.6eV) in the Fe 2p3/2 and 2p1/2 components were assigned to Fe2+, while the two peaks at the higher binding energies (706.8 and 720.7eV) in the Fe 2p3/2 and 2p1/2 components were assigned to Fe3+<a class="elsevierStyleCrossRefs" href="#bib0760">[64–66]</a>. With the presence of Fe2+ in the crystal, <a class="elsevierStyleCrossRef" href="#fig0045">Fig. 9</a>b(i–iii) shows the possible structural makeup of the samples. The structure is made up of a mixture of ZnAl2O4 with tet Zn2+ and oct Al3+ (<a class="elsevierStyleCrossRef" href="#fig0045">Fig. 9</a>b(i)), ZnFe2O4 with tet Zn2+ and oct Fe3+ (<a class="elsevierStyleCrossRef" href="#fig0045">Fig. 9</a>b(ii)), and Fe3O4 with tet Fe3+ and oct Fe2+ or Fe3+ (<a class="elsevierStyleCrossRef" href="#fig0045">Fig. 9</a>b(ii)).<elsevierMultimedia ident="fig0045"></elsevierMultimedia>The UV–vis spectrometer was used to measure the diffuse reflectance of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors in the wavelength range of 250–800nm and the spectra are shown in <a class="elsevierStyleCrossRef" href="#fig0050">Fig. 10</a>. The diffuse reflectance spectra show the ZnAl2O4 band-to-band transition around 305nm.<elsevierMultimedia ident="fig0050"></elsevierMultimedia>The band gaps of the phosphors were determined from the diffuse reflectance data using the derivative method and Kubelka–Munk function. In the derivative method, the band gap is determined by taking the first derivative, dR/dE, of the diffuse reflectance data and plotting it against the energy E (eV) <a class="elsevierStyleCrossRef" href="#bib0775">[67]</a> (the wavelength was converted to energy using the relation, E (eV)=1240/λ (nm)). In general, the absorption coefficient of a material is related to the band gap by<elsevierMultimedia ident="eq0060"></elsevierMultimedia>where h is Planck's constant, v is the frequency, Eg is the material band gap and n depends on the nature of the transition and can take values of ½, 3/2, 2 or 3 for allowed direct, forbidden direct, allowed indirect and forbidden indirect transitions, respectively. A is an energy independent proportionality constant <a class="elsevierStyleCrossRef" href="#bib0780">[68]</a>. Eq. <a class="elsevierStyleCrossRef" href="#eq0060">(9)</a> can be written as:<elsevierMultimedia ident="eq0065"></elsevierMultimedia>For a direct band gap material, the absorption coefficient is a function of energy, α(hv), hence Eq. <a class="elsevierStyleCrossRef" href="#eq0065">(10)</a> can be expressed as<elsevierMultimedia ident="eq0070"></elsevierMultimedia>Eq. <a class="elsevierStyleCrossRef" href="#eq0070">(11)</a> is true for hv>Eg but 0 if hv<Eg. Taking the first derivative of Eq. <a class="elsevierStyleCrossRef" href="#eq0070">(11)</a> with respect to hv gives<elsevierMultimedia ident="eq0075"></elsevierMultimedia>Eq. <a class="elsevierStyleCrossRef" href="#eq0075">(12)</a> diverges at a point when hc/E=hc/Eg, and this correspond to the band gap of a direct band gap material. At this point Eq. <a class="elsevierStyleCrossRef" href="#eq0075">(12)</a> is reduce to<elsevierMultimedia ident="eq0080"></elsevierMultimedia>For a direct band gap material, Eq. <a class="elsevierStyleCrossRef" href="#eq0080">(13)</a> show a distinct sharp peak, usually taken as the band gap of the material <a class="elsevierStyleCrossRef" href="#bib0775">[67]</a>. <a class="elsevierStyleCrossRef" href="#fig0055">Fig. 11</a> shows the plots of dR/dE versus E (eV) for the ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors. It is evident from <a class="elsevierStyleCrossRef" href="#fig0055">Fig. 11</a> that the band gap of the undoped ZnAl2O4 is about 4.23eV. This is in agreement with some of the ZnAl2O4 band gap reported in the literature <a class="elsevierStyleCrossRefs" href="#bib0785">[69,70]</a>. The band gap decreased slightly to 4.17eV when 0.01mol% of Fe3+ was doped into the matric. This could be due to the smaller band gap of ZnFe2O4<a class="elsevierStyleCrossRefs" href="#bib0795">[71,72]</a> compare to ZnAl2O4<a class="elsevierStyleCrossRefs" href="#bib0785">[69,70]</a>. However, no increased was observe in the band gap for a further increase in the concentration of Fe3+.<elsevierMultimedia ident="fig0055"></elsevierMultimedia>The Kubelka–Munk function is based on the direct and indirect proportionality relation between the absorption coefficient (α) of a material and the R, respectively. R is the reflectance of the material. For a semi-infinite medium, Kubelka–Munk is defined by Eq. <a class="elsevierStyleCrossRef" href="#eq0085">(14)</a>:<elsevierMultimedia ident="eq0085"></elsevierMultimedia>where R∞ is the reflectance of the semi-finite medium <a class="elsevierStyleCrossRef" href="#bib0805">[73]</a>. For a finite medium with 100%, Eq. <a class="elsevierStyleCrossRef" href="#eq0085">(14)</a> takes the form of Eq. <a class="elsevierStyleCrossRef" href="#eq0090">(15)</a>:<elsevierMultimedia ident="eq0090"></elsevierMultimedia>Considering that F(R∞) is proportional to the α, and equating Eqs. <a class="elsevierStyleCrossRefs" href="#eq0060">(9) and (15)</a> gives Eq. <a class="elsevierStyleCrossRef" href="#eq0095">(16)</a>:<elsevierMultimedia ident="eq0095"></elsevierMultimedia>From Eq. <a class="elsevierStyleCrossRef" href="#eq0095">(16)</a>, the band gap can be estimated by plotting a graph of (F(R100)hv)2 versus hv and drawing a straight line from the inflection point of the curve to the hv-axis. <a class="elsevierStyleCrossRef" href="#fig0060">Fig. 12</a> shows the (F(R100)hv)2 versus hv plot for the ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors. Interestingly, the values of the band gaps are in agreement with those estimated with the derivative method, with 4.20eV for the undoped ZnAl2O4 and 4.17eV for all the doped samples.<elsevierMultimedia ident="fig0060"></elsevierMultimedia>The non-increment in the band gap with increasing concentration of Fe3+ can be explained by Harrison's tight binding (TB) model <a class="elsevierStyleCrossRef" href="#bib0810">[74]</a>, which proposed that:<ul class="elsevierStyleList" id="lis0005"><li class="elsevierStyleListItem" id="lsti0005">(i)The top of the valence band of the host does not change significantly for a small concentration of the dopant and the doped matrix can be adequately explained within the virtual-crystal approximation method.</li><li class="elsevierStyleListItem" id="lsti0010">(ii)The position of the energy of the dopant (impurity) is independent of its concentration (even at the smallest possible concentration). However, at higher concentration, small shifting and broadening of the dopant states may occur (owing to the electrostatic interactions between the dopant atoms and/or the difference in the bond lengths of the host and the dopant within the matrix.</li></ul><a class="elsevierStyleCrossRef" href="#fig0065">Fig. 13</a>(a) and (b) shows the PL excitation and emission spectra of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors normalized with respect to the dopant concentration, respectively. The excitation spectra (<a class="elsevierStyleCrossRef" href="#fig0065">Fig. 13</a>(a)) was obtained when monitoring the emission at 483nm and scanning the spectrum in the wavelength range of 200–450nm. Within this wavelength range, two broad bands were observed from 200 to 275nm, with a maximum at 235nm, and from 325 to 415nm, with a maximum around 374nm. The peak at 235nm could be due to the band-to-band transition of ZnAl2O4. The broadband peaking around 374nm could be relate to ZnO band-to-band transition <a class="elsevierStyleCrossRef" href="#bib0815">[75]</a>. Similar transitions were observed from the absorbance and reflectance of the ZnAl2O4 samples <a class="elsevierStyleCrossRefs" href="#bib0460">[4,76,77]</a>. Under the 235nm excitation, two broad emission bands could be distinguished, one with a maximum around 483nm and the other around 730nm, as shown in <a class="elsevierStyleCrossRef" href="#fig0065">Fig. 13</a>(b).<elsevierMultimedia ident="fig0065"></elsevierMultimedia>The inset of <a class="elsevierStyleCrossRef" href="#fig0065">Fig. 13</a>(a) shows how the emission intensities of the 487 and 730nm bands varied with Fe3+ concentration. It is apparent from the inset of <a class="elsevierStyleCrossRef" href="#fig0065">Fig. 13</a>(a) that the emission intensity of the 487nm band dropped sharply after doping with just 0.01mol% of Fe3+, but as the concentration of Fe3+ increased, the change in the emission intensity became infinitesimal and intermittent. A similar trend in the luminescence intensity has been reported in ZnGa2O4 and ZnAl2O4<a class="elsevierStyleCrossRefs" href="#bib0830">[78,79]</a>. However, the 730nm emission band increased with the Fe3+ doping concentration, attaining maximum at 0.05mol% of Fe3+ and decreased afterwards. The emission band observed at 487nm in the ZnAl2O4 (x=0) is assigned to the defect related intra-band transitions, such as oxygen vacancies and Zn2+ interstitials in the spinel lattice <a class="elsevierStyleCrossRefs" href="#bib0450">[2,80]</a>. The quenching of the 487nm band on Fe3+ doping suggests that the introduction of Fe3+ into the ZnAl2O4 system must have decreased the oxygen vacancies and Zn interstitial sites <a class="elsevierStyleCrossRef" href="#bib0825">[77]</a>, with Fe3+ filling some of the Zn interstitials. This will lead to the creation of some Fe–O–Fe bonds in the matrix and hence resulting in the formation of ZnAl(2−x)Fex3+O4 composite. Contrary to the 487nm bands, the emission intensities of the bands at 730nm shows distinctive increment with Fe3+ concentration, with the highest emission intensity obtained from the samples with 0.05mol% of Fe3+. Observe the slight blue shift in the emission band maximum from 487 to 470nm for the undoped and 0.08mol Fe3+ doped sample. This indicates that these bands were not from the same origin. The emission bands at 470 and 730nm in Fe3+ doped samples are ascribed to Fe ions occupying the tet and oct sites of ZnAl2O4 host, respectively. The PL from the tet coordinated Fe ions is attributed to the 4E+4A1(4G)→6A1(6S) transition, while the oct coordinated Fe ions is attributed to the 4T2(4G)→6A1(6S) <a class="elsevierStyleCrossRef" href="#bib0845">[81]</a>. As observed from the XPS result (<a class="elsevierStyleCrossRef" href="#fig0045">Fig. 9</a>(a)), part of the Fe3+ was reduced to Fe2+, hence both the tet and the oct emission could be from a mixture of Fe2+ and Fe3+ ions.The decay curves originating from the 487 and 730nm emission under the 235nm excitation of the ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors are shown in <a class="elsevierStyleCrossRef" href="#fig0070">Fig. 14</a>(a) and (b), respectively. The decay curves were nicely fitted by a triple exponential equation given by Eq. <a class="elsevierStyleCrossRef" href="#eq0100">(17)</a>:<elsevierMultimedia ident="eq0100"></elsevierMultimedia>with I the PL intensity, A, B and C are the fitting parameters, while τ1, τ2 and τ3 are the decay constants of the exponential components <a class="elsevierStyleCrossRef" href="#bib0850">[82]</a>. The average decay time τ* can be determined using Eq. <a class="elsevierStyleCrossRef" href="#eq0105">(18)</a>:<elsevierMultimedia ident="eq0105"></elsevierMultimedia><elsevierMultimedia ident="fig0070"></elsevierMultimedia>The calculated average decay times for the 487 and 730nm emission bands under 235nm excitation are shown in <a class="elsevierStyleCrossRef" href="#tbl0030">Table 6</a>. The inset of <a class="elsevierStyleCrossRef" href="#fig0070">Fig. 14</a>(a) shows the plot of the average lifetime of the phosphors versus the Fe3+ concentration (x) for the 487nm emission under 235nm excitation. The undoped sample (i.e. ZnAl2O4) has the longest lifetime, after which there was a decrease in the lifetime upon Fe3+ doping. The lifetime measured from the 730nm emission when under the 235nm excitation showed similar behavior like the one observed from the 487nm, but in an opposite manner. As seen in the inset of <a class="elsevierStyleCrossRef" href="#fig0070">Fig. 14</a>(b), the undoped sample has the shortest lifetime, and the lifetime increased upon Fe3+ doping. The change in the lifetime upon Fe3+ doping is a demonstration of that the emissions arises from different lattice sites <a class="elsevierStyleCrossRef" href="#bib0855">[83]</a>. This is a further proof of the existence of the tet and oct Fe sites within the ZnAl(2−x)Fex3+O4 matrix.<elsevierMultimedia ident="tbl0030"></elsevierMultimedia><a class="elsevierStyleCrossRef" href="#fig0075">Fig. 15</a>(a) is a schematic energy diagram showing the emission of Fe, zinc interstitials and oxygen vacancies in ZnAl2O4 host. The valence (VB) band is formed by the hybridization of O2− 2p orbitals and Zn2+ 3d orbitals, while the conduction band (CB) is formed by Al 3s and 2p orbitals <a class="elsevierStyleCrossRefs" href="#bib0460">[4,84,85]</a>. Upon excitation at 235nm UV-light, electrons excited from the VB to the CB are relaxed non-radiatively to the various luminescent centers in the material before giving emissions. Since the combination of ZnAl2O4 and Fe3O4 gives a solid solution of the form, (Zn8−x2+Fex3+)tet[Al8−x3+Fex3+F82+]octO32, with Fe ions in the both sites. The implication of this is that part of the Fe3+ are reduce to Fe2+ in both tet and oct sites. Therefore, the Fe emission from the tet and oct comprises Fe3+ and Fe2+ emissions. <a class="elsevierStyleCrossRef" href="#fig0075">Fig. 15</a>(b) illustrates further the schematic energy diagram of Fe ions (Fe3+ and Fe2+) on the tet and the oct sites of ZnAl2O4 host. The Fe2+ ions were generated due to the photoionization Fe3+ that results to the formation of bound-hole state via the equation: Fe3++hv→[Fe2+, h] <a class="elsevierStyleCrossRef" href="#bib0870">[86]</a>. The tet site is composed of two emission lines at 470 and 576nm assigned to the 4E+4A1(4G)→6A1(6S) and 4T2(4G)→6A1(6S) transitions of Fe3+, respectively, while the oct site gave an emission line at 730nm (4T1(4G)→6A1(6S)) <a class="elsevierStyleCrossRef" href="#bib0845">[81]</a>. The recombination of the trapped electrons (bound-hole state) in the tet and oct sites has not been for ZnAl2O2:Fe3+. However, it has been reported around 693 and 844nm for the oct and tet sites in Fe3O4 (inverse spinel) <a class="elsevierStyleCrossRef" href="#bib0875">[87]</a>, respectively.<elsevierMultimedia ident="fig0075"></elsevierMultimedia><a class="elsevierStyleCrossRef" href="#fig0080">Fig. 16</a>(a) and (b) compares the PL spectra of Zn(1−x)Fex3+Al2O4 and ZnAl(2−x)Fex3+O4 (x=0.05, i.e. Zn(0.95)Fe0.053+Al2O4 and ZnAl(1.95)Fe0.053+O4), respectively, taking into account the influence of charge compensation. It is evident from <a class="elsevierStyleCrossRef" href="#fig0080">Fig. 16</a> that the PL intensity of the sample where Fe3+ substituted Al3+ (<a class="elsevierStyleCrossRef" href="#fig0080">Fig. 16</a>(b)) is about twice that of the sample where Fe3+ substituted Zn2+ (<a class="elsevierStyleCrossRef" href="#fig0080">Fig. 16</a>(a)). The decreased luminescence intensity in <a class="elsevierStyleCrossRef" href="#fig0080">Fig. 16</a>(b) is attributed to the charge imbalance in the matrix due to the substitution of divalent Zn2+ ion by trivalent Fe3+ ion. Charge imbalance can lead to the formation of charge defects in the host lattice and hence creating non-radiative luminescence centers in the material <a class="elsevierStyleCrossRef" href="#bib0525">[17]</a>.<elsevierMultimedia ident="fig0080"></elsevierMultimedia><a class="elsevierStyleCrossRef" href="#fig0085">Fig. 17</a> shows CL spectra of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08). Generally, the wavelengths of the CL peak maximum shifted with respect to the PL peaks. The peak maximum observed at 487nm in the PL result shifted to 503nm for the undoped sample and 486nm for the doped samples, while the PL maximum observed at 730nm shifted to 703nm. The shift observed in the wavelength maximum of the CL spectra compared to the PL spectra could be relate to the different excitation sources used to excite the samples in both cases. During PL, the charge carriers are excited using photons, while the charge carriers in CL are excited using high-energy electrons. CL can provide a better spatial resolution than PL, this can be correlated to the small beam diameter (<10nm) of the electron beam <a class="elsevierStyleCrossRef" href="#bib0880">[88]</a>. Similar to the PL spectra (<a class="elsevierStyleCrossRef" href="#fig0065">Fig. 13</a>(a)), the band maximum observed at 503nm in the undoped sample shifts to lower wavelength with increasing Fe3+ concentration, but the 703nm peak remain at the similar position.<elsevierMultimedia ident="fig0085"></elsevierMultimedia>ConclusionThe Pechini synthesis method has proven to be an easy route to prepare ZnAl2O4 doped Fe3+ phosphors. The XRD results confirmed that the phosphors crystallized at a very low annealing temperature (600°C). The crystallite sizes estimated from the XRD data were smaller than the grain size estimated from the FE-SEM micrograph due to the formation of polycrystalline aggregates in the FE-SEM micrograph. The oxygen parameter (u) and the inversion degrees (y) of the phosphors were estimated from the XRD data. The XPS results confirmed the presence of Fe ions in both the tet and oct sites of ZnAl2O4. Furthermore, the XPS data also confirmed that Fe2+ ions were present in the samples doped with Fe3+, suggesting the reduction of some of the Fe3+ ions to Fe2+ ions. From the diffuse reflectance data, the band gaps of the phosphors estimated using the Kubelka–Munk equation and the derivative method gave similar values. In agreement with the XPS result, the PL and the CL study of the phosphors showed two broad bands at around 470 and 730nm which were assigned to the 4E+4A1(4G)→6A1(6S) and 4T2(4G)→6A1(6S) electronic transitions of Fe3+ ions occupying the tet and the oct sites in the spinel ZnAl2O4 host, respectively." "textoCompletoSecciones" => array:1 [ "secciones" => array:10 [ 0 => array:3 [ "identificador" => "xres1524490" "titulo" => "Abstract" "secciones" => array:1 [ 0 => array:1 [ "identificador" => "abst0005" ] ] ] 1 => array:2 [ "identificador" => "xpalclavsec1382328" "titulo" => "Keywords" ] 2 => array:3 [ "identificador" => "xres1524491" "titulo" => "Resumen" "secciones" => array:1 [ 0 => array:1 [ "identificador" => "abst0010" ] ] ] 3 => array:2 [ "identificador" => "xpalclavsec1382329" "titulo" => "Palabras clave" ] 4 => array:2 [ "identificador" => "sec0005" "titulo" => "Introduction" ] 5 => array:3 [ "identificador" => "sec0010" "titulo" => "Experimental" "secciones" => array:2 [ 0 => array:2 [ "identificador" => "sec0015" "titulo" => "Synthesis" ] 1 => array:2 [ "identificador" => "sec0020" "titulo" => "Characterization" ] ] ] 6 => array:2 [ "identificador" => "sec0025" "titulo" => "Results and discussion" ] 7 => array:2 [ "identificador" => "sec0030" "titulo" => "Conclusion" ] 8 => array:2 [ "identificador" => "xack535380" "titulo" => "Acknowledgements" ] 9 => array:1 [ "titulo" => "References" ] ] ] "pdfFichero" => "main.pdf" "tienePdf" => true "fechaRecibido" => "2019-12-02" "fechaAceptado" => "2020-02-26" "PalabrasClave" => array:2 [ "en" => array:1 [ 0 => array:4 [ "clase" => "keyword" "titulo" => "Keywords" "identificador" => "xpalclavsec1382328" "palabras" => array:5 [ 0 => "Luminescence" 1 => "Lifetime" 2 => "Microscopy" 3 => "Spectroscopy" 4 => "Inversion degree" ] ] ] "es" => array:1 [ 0 => array:4 [ "clase" => "keyword" "titulo" => "Palabras clave" "identificador" => "xpalclavsec1382329" "palabras" => array:6 [ 0 => "Fósforos" 1 => "Luminiscencia" 2 => "Toda la vida" 3 => "Microscopía" 4 => "Espectroscopia" 5 => "Grado de inversión" ] ] ] ] "tieneResumen" => true "resumen" => array:2 [ "en" => array:2 [ "titulo" => "Abstract" "resumen" => "ZnAl2O4 doped with various concentration (x) of Fe3+ were prepared using the Pechini synthesis. In the first set of samples, Fe3+ substituted Al3+ to create a system of the form ZnAl(2−x)Fex3+O4 (x=0–0.08). To study the effect of charge compensation, Fe3+ substituted Zn2+ to create Zn(1−x)Fex3+Al2O4 (x=0.05) system. The structure and particle morphology of the phosphors were studied using X-ray diffractometer (XRD) and field emission scanning electron spectroscopy, respectively. From the XRD data, the oxygen parameter and the inversion degrees were estimated. The elemental composition and electronic states of the phosphors were analyzed using X-ray photoelectron spectroscopy (XPS). XPS results showed that part of the Fe3+ were reduced to Fe2+ in the doped samples. Both photoluminescence and cathodoluminescence properties of the phosphors were also studied. Luminescence excitations using a xenon lamp and X-ray showed two broad emission bands located around 470 and 730nm, and were ascribed to Fe ions occupying the tetrahedral (tet) and the octahedral (oct) sites in ZnAl2O4, respectively. A change in the lifetime of these two emission bands upon Fe doping further confirmed the existence of Fe in the tet and oct sites in the ZnAl(2−x)Fex3+O4 matrix." ] "es" => array:2 [ "titulo" => "Resumen" "resumen" => "Se preparó ZnAl2O4 dopado con varias concentraciones (x) de Fe3+ usando la síntesis de Pechini. En el primer conjunto de muestras, Fe3+ sustituyó Al3+ para crear un sistema de la forma ZnAl(2−x)Fex3+O4 (x=0 a 0,08). Para estudiar el efecto de la compensación de carga, Fe3+ sustituyó Zn2+ para crear el sistema Zn(1−x)Fex3+Al2O4 (x=0,05). La estructura y la morfología de las partículas de los fósforos se estudiaron utilizando un difractómetro de rayos X (XRD) y espectroscopía electrónica de barrido de emisión de campo, respectivamente. A partir de los datos XRD se estimaron el parámetro de oxígeno y los grados de inversión. La composición elemental y los estados electrónicos de los fósforos se analizaron mediante espectroscopía de fotoelectrones de rayos X (XPS). Los resultados de XPS mostraron que parte de Fe3+ se redujo a Fe2+ en las muestras dopadas. También se estudiaron las propiedades de fotoluminiscencia y catodoluminiscencia de los fósforos. Las excitaciones de luminiscencia usando una lámpara de xenón y rayos X mostraron dos amplias bandas de emisión ubicadas alrededor de 470 y 730nm, y se atribuyeron a iones Fe que ocupan los sitios tetraédricos (tet) y octaédrico (oct) en ZnAl2O4, respectivamente. Un cambio en la vida útil de estas dos bandas de emisión después del dopaje con Fe confirmó aún más la existencia de Fe en los sitios tet y oct en la matriz ZnAl(2−x)Fex3+O4." ] ] "multimedia" => array:44 [ 0 => array:7 [ "identificador" => "fig0005" "etiqueta" => "Fig. 1" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr1.jpeg" "Alto" => 1143 "Ancho" => 1500 "Tamanyo" => 204759 ] ] "descripcion" => array:1 [ "en" => "Diagrammatic illustration of the ZnAl2O4 spinel structure showing; (a) a unit cell with five oct sites (mint green) and seven tet sites (lilac blue), (b) double tet and (c) oct coordinates." ] ] 1 => array:7 [ "identificador" => "fig0010" "etiqueta" => "Fig. 2" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr2.jpeg" "Alto" => 2344 "Ancho" => 2341 "Tamanyo" => 386882 ] ] "descripcion" => array:1 [ "en" => "The XRD patterns of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05 and 0.08) and the JCPDS standard." ] ] 2 => array:7 [ "identificador" => "fig0015" "etiqueta" => "Fig. 3" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr3.jpeg" "Alto" => 1091 "Ancho" => 1508 "Tamanyo" => 113205 ] ] "descripcion" => array:1 [ "en" => "A graph of the lattice parameter (a) of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) as a function of the Fe3+ ion concentration." ] ] 3 => array:7 [ "identificador" => "fig0020" "etiqueta" => "Fig. 4" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr4.jpeg" "Alto" => 2407 "Ancho" => 1508 "Tamanyo" => 273593 ] ] "descripcion" => array:1 [ "en" => "The FE-SEM images of ZnAl(2−x)Fex3+O4 (a) x=0 and (b) x=0.08. The inset of (a) and (b) depicts the average particle size distribution curves for the images thereof." ] ] 4 => array:7 [ "identificador" => "fig0025" "etiqueta" => "Fig. 5" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr5.jpeg" "Alto" => 1769 "Ancho" => 1508 "Tamanyo" => 142249 ] ] "descripcion" => array:1 [ "en" => "The EDS spectra of ZnAl(2−x)Fex3+O4 (a) x=0 and (b) x=0.08. The inset of (a) and (b) are the at.% elemental concentration." ] ] 5 => array:7 [ "identificador" => "fig0030" "etiqueta" => "Fig. 6" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr6.jpeg" "Alto" => 2473 "Ancho" => 2175 "Tamanyo" => 317783 ] ] "descripcion" => array:1 [ "en" => "The fitted high-resolution O 1s XPS spectra of ZnAl(2−x)Fex3+O4, (a) x=0, (b) x=0.01, (c) x=0.05 and (d) x=0.08." ] ] 6 => array:7 [ "identificador" => "fig0035" "etiqueta" => "Fig. 7" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr7.jpeg" "Alto" => 2622 "Ancho" => 2175 "Tamanyo" => 372130 ] ] "descripcion" => array:1 [ "en" => "The fitted high-resolution Al 2p XPS spectra for ZnAl(2−x)Fex3+O4, (a) x=0, (b) x=0.01, (c) x=0.05 and (d) x=0.08." ] ] 7 => array:7 [ "identificador" => "fig0040" "etiqueta" => "Fig. 8" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr8.jpeg" "Alto" => 2056 "Ancho" => 2175 "Tamanyo" => 339456 ] ] "descripcion" => array:1 [ "en" => "The fitted high-resolution Zn 2p XPS spectra of the ZnAl(2−x)Fex3+O4, (a) x=0, (b) x=0.01, (c) x=0.05 and (d) x=0.08." ] ] 8 => array:7 [ "identificador" => "fig0045" "etiqueta" => "Fig. 9" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr9.jpeg" "Alto" => 1329 "Ancho" => 2091 "Tamanyo" => 234303 ] ] "descripcion" => array:1 [ "en" => "(a) The fitted high-resolution Fe 2p XPS spectra of the ZnAl2O4: 4% Fe3+. (b) The structural makeup of ZnAl2O4:Fe3+." ] ] 9 => array:7 [ "identificador" => "fig0050" "etiqueta" => "Fig. 10" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr10.jpeg" "Alto" => 1047 "Ancho" => 1341 "Tamanyo" => 132737 ] ] "descripcion" => array:1 [ "en" => "The diffuse reflectance spectra of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors." ] ] 10 => array:7 [ "identificador" => "fig0055" "etiqueta" => "Fig. 11" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr11.jpeg" "Alto" => 1874 "Ancho" => 1508 "Tamanyo" => 271961 ] ] "descripcion" => array:1 [ "en" => "The plots of dR/dE versus E (eV) for the ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors." ] ] 11 => array:7 [ "identificador" => "fig0060" "etiqueta" => "Fig. 12" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr12.jpeg" "Alto" => 1109 "Ancho" => 2091 "Tamanyo" => 239928 ] ] "descripcion" => array:1 [ "en" => "The plot of (F(R100)hv)2 versus hv for the ZnAl(2−x)Fex3+O4, (a) x=0, (b) x=0.01, (c) x=0.025, (d) x=0.05, and (e) x=0.08." ] ] 12 => array:7 [ "identificador" => "fig0065" "etiqueta" => "Fig. 13" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr13.jpeg" "Alto" => 2129 "Ancho" => 1508 "Tamanyo" => 295041 ] ] "descripcion" => array:1 [ "en" => "The PL (a) excitation (under 487nm emission) and (b) emission (under 235nm excitation) spectra of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors normalized with respect to the dopant concentration. The inset of (a) shows the variation of the 487 and 730nm bands as a function of Fe3+ concentration." ] ] 13 => array:7 [ "identificador" => "fig0070" "etiqueta" => "Fig. 14" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr14.jpeg" "Alto" => 2101 "Ancho" => 1508 "Tamanyo" => 319579 ] ] "descripcion" => array:1 [ "en" => "The decays curves for ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors when monitoring (a) 487nm and (b) 730nm emission under 235nm excitation. The insets of (a) and (b) are the plot of the average lifetime of the phosphors versus the Fe3+ concentration (x) for the 487nm emission and 730nm emissions, respectively." ] ] 14 => array:7 [ "identificador" => "fig0075" "etiqueta" => "Fig. 15" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr15.jpeg" "Alto" => 2081 "Ancho" => 1508 "Tamanyo" => 317976 ] ] "descripcion" => array:1 [ "en" => "Schematic energy diagrams showing, (a) the emission of Fe, zinc interstitials and oxygen vacancies in ZnAl2O4 host and (b) the electronic transitions Fe ions (Fe3+ and Fe2+) on the tet and the oct sites of ZnAl2O4 host." ] ] 15 => array:7 [ "identificador" => "fig0080" "etiqueta" => "Fig. 16" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr16.jpeg" "Alto" => 950 "Ancho" => 1341 "Tamanyo" => 116270 ] ] "descripcion" => array:1 [ "en" => "The PL emission spectra of (a) Zn(1−x)Fex3+Al2O4 and (b) ZnAl(2−x)Fex3+O4 for x=0.05, excited at 235nm." ] ] 16 => array:7 [ "identificador" => "fig0085" "etiqueta" => "Fig. 17" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr17.jpeg" "Alto" => 1948 "Ancho" => 1508 "Tamanyo" => 267848 ] ] "descripcion" => array:1 [ "en" => "The CL spectra of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors." ] ] 17 => array:8 [ "identificador" => "tbl0005" "etiqueta" => "Table 1" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at1" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:1 [ "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Ions \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Tet ionic radius (nm) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Oct ionic radius (nm) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Ref. \t\t\t\t\t\t\n \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Zn2+ \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.06 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.074 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="" valign="\n \t\t\t\t\ttop\n \t\t\t\t"> \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Al3+ \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.039 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.054 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t"><a class="elsevierStyleCrossRef" href="#bib0570">[26]</a> \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Fe3+ \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.049 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.065 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="" valign="\n \t\t\t\t\ttop\n \t\t\t\t"> \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Fe2+ \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.063 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.078 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="" valign="\n \t\t\t\t\ttop\n \t\t\t\t"> \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab2620339.png" ] ] ] ] "descripcion" => array:1 [ "en" => "The ionic radii of Zn2+, Al3+, Fe3+ and Fe2+ in the tet and oct coordinates." ] ] 18 => array:8 [ "identificador" => "tbl0010" "etiqueta" => "Table 2" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at2" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:1 [ "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">ZnAl(2−x)Fex3+O4 \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Crystallite size (L) (nm) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Strain (ɛ)×e−4 \t\t\t\t\t\t\n \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">27.8 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">10.8 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.01 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">33.5 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">11.2 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.025 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">41.8 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">14.7 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.05 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">80.6 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">17.6 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.08 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">86.6 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">17.6 \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab2620337.png" ] ] ] ] "descripcion" => array:1 [ "en" => "Estimated crystallite sizes and strain of ZnAl(2−x)Fex3+O4 (x=0, 0.01, 0.025, 0.05, 0.08) phosphors." ] ] 19 => array:8 [ "identificador" => "tbl0015" "etiqueta" => "Table 3" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at3" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:2 [ "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">X \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">a (Å) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">u (literature) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">u (calculated) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">y (literature) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">y (calculated) \t\t\t\t\t\t\n \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8.054±0.001 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.261<a class="elsevierStyleCrossRef" href="#tblfn0005">*</a> \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.00<a class="elsevierStyleCrossRef" href="#tblfn0005">*</a> \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.01 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8.060±0.001 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.261 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.04 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.025 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8.066±0.001 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.262 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.08 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.05 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8.075±0.001 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.262 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.11 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.08 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8.085±0.001 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.262 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.15 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Fe3O4 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8.392<a class="elsevierStyleCrossRef" href="#tblfn0005">*</a> \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.255<a class="elsevierStyleCrossRef" href="#tblfn0005">*</a> \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1.00<a class="elsevierStyleCrossRef" href="#tblfn0005">*</a> \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab2620340.png" ] ] ] "notaPie" => array:1 [ 0 => array:3 [ "identificador" => "tblfn0005" "etiqueta" => "*" "nota" => "<a class="elsevierStyleCrossRef" href="#bib0590">[30]</a>." ] ] ] "descripcion" => array:1 [ "en" => "The lattice parameters and inversion degree of different spinel composition." ] ] 20 => array:8 [ "identificador" => "tbl0020" "etiqueta" => "Table 4" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at4" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:2 [ "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Cation \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Rtet (calculated) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Rtet (literature) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Roct (calculated) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Roct (literature) \t\t\t\t\t\t\n \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Zn2+ \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1.8971 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1.9493<a class="elsevierStyleCrossRef" href="#tblfn0015">**</a> \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Fe2+ \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1.9950<a class="elsevierStyleCrossRef" href="#tblfn0010">*</a> \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">2.0996 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">2.0800<a class="elsevierStyleCrossRef" href="#tblfn0020">***</a> \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Fe3+ \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1.8867 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">2.0175 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">2.0300<a class="elsevierStyleCrossRef" href="#tblfn0020">***</a> \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Al3+ \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">– \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1.9289 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1.9169<a class="elsevierStyleCrossRef" href="#tblfn0015">**</a> \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab2620338.png" ] ] ] "notaPie" => array:3 [ 0 => array:3 [ "identificador" => "tblfn0010" "etiqueta" => "*" "nota" => "<a class="elsevierStyleCrossRef" href="#bib0590">[30]</a>." ] 1 => array:3 [ "identificador" => "tblfn0015" "etiqueta" => "**" "nota" => "<a class="elsevierStyleCrossRef" href="#bib0615">[35]</a>." ] 2 => array:3 [ "identificador" => "tblfn0020" "etiqueta" => "***" "nota" => "<a class="elsevierStyleCrossRef" href="#bib0620">[36]</a>." ] ] ] "descripcion" => array:1 [ "en" => "Calculated bond lengths of the cations-O in ZnAl(2−x)Fex3+O4 system in the tet and oct sites compared to the literatures." ] ] 21 => array:8 [ "identificador" => "tbl0025" "etiqueta" => "Table 5" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at5" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:1 [ "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td-with-role" title="\n \t\t\t\t\ttable-head\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col">Samples \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " colspan="4" align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Elements/compositions (at.%)</th></tr><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">ZnAl(2−x)Fex3+O4 \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Zn \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Al \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">O \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Fe \t\t\t\t\t\t\n \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">14.4 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">27.6 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">58.0 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.01 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">14.5 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">28.0 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">57.5 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.025 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">14.6 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">28.3 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">57.1 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.05 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">14.6 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">28.2 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">57.1 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.1 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.08 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">14.6 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">28.0 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">57.3 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.1 \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab2620336.png" ] ] ] ] "descripcion" => array:1 [ "en" => "Elemental composition and concentration ZnAl(2−x)Fex3+O4 phosphors (x=0, 0.01, 0.025, 0.05 and 0.08)." ] ] 22 => array:8 [ "identificador" => "tbl0030" "etiqueta" => "Table 6" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at6" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:1 [ "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td-with-role" title="\n \t\t\t\t\ttable-head\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col">ZnAl(2−x)Fex3+O4 \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " colspan="2" align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Average lifetime (ms), λExc.=235nm</th></tr><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black"> \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">λEmi.=487nm \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="center" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">λEmi.=730nm \t\t\t\t\t\t\n \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.21(3) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">6.4(9) \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.01 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.20(3) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8.2(3) \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.025 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.20(2) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">7.8(4) \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.05 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.20(4) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8.0(4) \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">x=0.08 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.20(1) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">8.2(1) \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab2620335.png" ] ] ] ] "descripcion" => array:1 [ "en" => "The average lifetime of ZnAl(2−x)Fex3+ O4 (x=0, 0.01, 0.025, 0.05 and 0.08) for 487 and 730nm emissions, when monitoring the excitation at 235nm." ] ] 23 => array:6 [ "identificador" => "eq0005" "etiqueta" => "(1)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "βh k l Cos θ=κλL+4ε Sin θ" "Fichero" => "STRIPIN_si4.jpeg" "Tamanyo" => 1721 "Alto" => 30 "Ancho" => 166 ] ] 24 => array:6 [ "identificador" => "eq0010" "etiqueta" => "(2)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "a2=d2(h2+k2+l2)" "Fichero" => "STRIPIN_si9.jpeg" "Tamanyo" => 1187 "Alto" => 17 "Ancho" => 133 ] ] 25 => array:6 [ "identificador" => "eq0015" "etiqueta" => "(3)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "d=λ2 Sin θ" "Fichero" => "STRIPIN_si10.jpeg" "Tamanyo" => 974 "Alto" => 30 "Ancho" => 71 ] ] 26 => array:6 [ "identificador" => "eq0020" "etiqueta" => "(4)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "Rtet=a3u−18" "Fichero" => "STRIPIN_si11.jpeg" "Tamanyo" => 1470 "Alto" => 40 "Ancho" => 133 ] ] 27 => array:6 [ "identificador" => "eq0025" "etiqueta" => "(5)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "Roct=a3u2−2u+1381/2" "Fichero" => "STRIPIN_si12.jpeg" "Tamanyo" => 1970 "Alto" => 43 "Ancho" => 187 ] ] 28 => array:6 [ "identificador" => "eq0030" "etiqueta" => "[1]" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "(Zn82+)tet[Al163+]octO32" "Fichero" => "STRIPIN_si13.jpeg" "Tamanyo" => 1656 "Alto" => 19 "Ancho" => 147 ] ] 29 => array:6 [ "identificador" => "eq0035" "etiqueta" => "[2]" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "(Fe83+)tet[F83+F82+]octO32" "Fichero" => "STRIPIN_si14.jpeg" "Tamanyo" => 1548 "Alto" => 18 "Ancho" => 159 ] ] 30 => array:6 [ "identificador" => "eq0040" "etiqueta" => "[3]" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "(Zn8−x2+Fex3+)tet[Al8−x3+Fex3+F82+]octO32" "Fichero" => "STRIPIN_si15.jpeg" "Tamanyo" => 2717 "Alto" => 19 "Ancho" => 267 ] ] 31 => array:6 [ "identificador" => "eq0045" "etiqueta" => "(6)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "Rtet=∑iziRi" "Fichero" => "STRIPIN_si16.jpeg" "Tamanyo" => 1069 "Alto" => 35 "Ancho" => 89 ] ] 32 => array:6 [ "identificador" => "eq0050" "etiqueta" => "(7)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "Rtet=0.99RZn2+,tet+yRFe3+,tet+(0.01−y)RFe2+,tet" "Fichero" => "STRIPIN_si17.jpeg" "Tamanyo" => 2446 "Alto" => 17 "Ancho" => 320 ] ] 33 => array:6 [ "identificador" => "eq0055" "etiqueta" => "(8)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "Roct=1.99RAl3+,oct+(0.01−y)RFe3+,oct+yRFe2+,oct2" "Fichero" => "STRIPIN_si18.jpeg" "Tamanyo" => 3100 "Alto" => 34 "Ancho" => 325 ] ] 34 => array:6 [ "identificador" => "eq0060" "etiqueta" => "(9)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "(αhv)1/n=A(hv−Eg)" "Fichero" => "STRIPIN_si20.jpeg" "Tamanyo" => 1327 "Alto" => 20 "Ancho" => 140 ] ] 35 => array:6 [ "identificador" => "eq0065" "etiqueta" => "(10)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "α=A(hv−Eg)nhv" "Fichero" => "STRIPIN_si21.jpeg" "Tamanyo" => 1344 "Alto" => 34 "Ancho" => 108 ] ] 36 => array:6 [ "identificador" => "eq0070" "etiqueta" => "(11)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "α(hv)=A(hv−Eg)nhv" "Fichero" => "STRIPIN_si23.jpeg" "Tamanyo" => 1675 "Alto" => 34 "Ancho" => 134 ] ] 37 => array:6 [ "identificador" => "eq0075" "etiqueta" => "(12)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "dα(hv)d(hv)=Ahv−(hv−Eg)nhv+n(hv−Eg)n−1 hv>Eg" "Fichero" => "STRIPIN_si24.jpeg" "Tamanyo" => 4228 "Alto" => 40 "Ancho" => 371 ] ] 38 => array:6 [ "identificador" => "eq0080" "etiqueta" => "(13)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "dα(hv)d(hv)E=Eg→∞ n=1/2" "Fichero" => "STRIPIN_si25.jpeg" "Tamanyo" => 1909 "Alto" => 44 "Ancho" => 181 ] ] 39 => array:6 [ "identificador" => "eq0085" "etiqueta" => "(14)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "F(R∞)=(1−R∞)22R∞" "Fichero" => "STRIPIN_si26.jpeg" "Tamanyo" => 1979 "Alto" => 41 "Ancho" => 145 ] ] 40 => array:6 [ "identificador" => "eq0090" "etiqueta" => "(15)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "F(R100)=(1−R100)22R100" "Fichero" => "STRIPIN_si28.jpeg" "Tamanyo" => 2284 "Alto" => 41 "Ancho" => 157 ] ] 41 => array:6 [ "identificador" => "eq0095" "etiqueta" => "(16)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "(F(R100)hv)1/n=A(hv−Eg)" "Fichero" => "STRIPIN_si31.jpeg" "Tamanyo" => 1656 "Alto" => 20 "Ancho" => 174 ] ] 42 => array:6 [ "identificador" => "eq0100" "etiqueta" => "(17)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "I=A exp−tτ1+B exp−tτ2+−tτ3" "Fichero" => "STRIPIN_si32.jpeg" "Tamanyo" => 3151 "Alto" => 40 "Ancho" => 296 ] ] 43 => array:6 [ "identificador" => "eq0105" "etiqueta" => "(18)" "tipo" => "MULTIMEDIAFORMULA" "mostrarFloat" => false "mostrarDisplay" => true "Formula" => array:5 [ "Matematica" => "τ*=Aτ12+Bτ22+Cτ32Aτ1+Bτ2+Cτ3" "Fichero" => "STRIPIN_si37.jpeg" "Tamanyo" => 2409 "Alto" => 35 "Ancho" => 141 ] ] ] "bibliografia" => array:2 [ "titulo" => "References" "seccion" => array:1 [ 0 => array:2 [ "identificador" => "bibs0015" "bibliografiaReferencia" => array:88 [ 0 => array:3 [ "identificador" => "bib0445" "etiqueta" => "[1]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Luminescence properties of ZnGa2O4 and ZnAl2O4 spinels doped with Eu3+ and Tb3+ ions" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Phys. Stat. Solidi C" "fecha" => "2009" "volumen" => "6" "paginaInicial" => "1199" "paginaFinal" => "1202" ] ] ] ] ] ] 1 => array:3 [ "identificador" => "bib0450" "etiqueta" => "[2]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Photoluminescence and EPR studies on Fe3+ doped ZnAl2O4: an evidence for local site swapping of Fe3+ and formation of inverse and normal phase" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1039/c4dt00741g" "Revista" => array:6 [ "tituloSerie" => "Dalton Trans." "fecha" => "2014" "volumen" => "43" "paginaInicial" => "9313" "paginaFinal" => "9323" "link" => array:1 [ …1] ] ] ] ] ] ] 2 => array:3 [ "identificador" => "bib0455" "etiqueta" => "[3]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Dynamics of the cation mixing of MgAl2O4 and ZnAl2O4 spinel" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Am. Ceram. Soc." "fecha" => "1999" "volumen" => "82" "paginaInicial" => "1844" "paginaFinal" => "1848" ] ] ] ] ] ] 3 => array:3 [ "identificador" => "bib0460" "etiqueta" => "[4]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Structure of spinel" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Am. Ceram. Soc." "fecha" => "1999" "volumen" => "82" "paginaInicial" => "3279" "paginaFinal" => "3292" ] ] ] ] ] ] 4 => array:3 [ "identificador" => "bib0465" "etiqueta" => "[5]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Materials science for the experimental mechanist" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "LibroEditado" => array:4 [ "editores" => "W.N.SharpeJr." "titulo" => "Springer Handbook of Experimental Solid Mechanics" "paginaInicial" => "25" "serieFecha" => "2008" ] ] ] ] ] ] 5 => array:3 [ "identificador" => "bib0470" "etiqueta" => "[6]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Relation of AIIBIII2XVI4 compounds to other materials their properties and applications" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "LibroEditado" => array:5 [ "editores" => "F.J.Manjon, I.Tiginyanu, V.Ursaki" "titulo" => "Pressure-induced Phase Transitions in AB2X4 Chalcogenide Compounds" "paginaInicial" => "1" "paginaFinal" => "50" "serieFecha" => "2014" ] ] ] ] ] ] 6 => array:3 [ "identificador" => "bib0475" "etiqueta" => "[7]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "A comparison between rare earth and transition metals working as magnetic materials in an AMR refrigerator in the room temperature range" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Appl. Therm. Eng." "fecha" => "2015" "volumen" => "91" "paginaInicial" => "767" "paginaFinal" => "777" ] ] ] ] ] ] 7 => array:3 [ "identificador" => "bib0480" "etiqueta" => "[8]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Fe3+ red phosphors based on lithium aluminates and an aluminum lithium oxyfluoride prepared from LiF as the Li source" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Lumin." "fecha" => "2017" "volumen" => "182" "paginaInicial" => "53" "paginaFinal" => "58" ] ] ] ] ] ] 8 => array:3 [ "identificador" => "bib0485" "etiqueta" => "[9]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Color-tunable luminescence and energy transfer of Eu2+/Mn2+ co-doped Sr9Lu(PO4)7 phosphors for white LEDs" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Polyhedron" "fecha" => "2018" "volumen" => "141" "paginaInicial" => "284" "paginaFinal" => "288" ] ] ] ] ] ] 9 => array:3 [ "identificador" => "bib0490" "etiqueta" => "[10]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Luminescence lifetime thermometry with Mn3+–Mn4+ co-doped nanocrystals" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Mater. Chem. C" "fecha" => "2018" "volumen" => "6" "paginaInicial" => "7092" "paginaFinal" => "7100" ] ] ] ] ] ] 10 => array:3 [ "identificador" => "bib0495" "etiqueta" => "[11]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Transition metal-doped chalcogenide glasses for broadband near-infrared sources" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "LibroEditado" => array:5 [ "editores" => "A.C.J.A.C.Terry, W.A.Clarkson" "titulo" => "Solid State Laser Technologies and Femtosecond Phenomena, SPIE, vol. 5620" "paginaInicial" => "289" "paginaFinal" => "296" "serieFecha" => "2004" ] ] ] ] ] ] 11 => array:3 [ "identificador" => "bib0500" "etiqueta" => "[12]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Laser materials based on transition metal ions" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Opt. Mater." "fecha" => "2017" "volumen" => "63" "paginaInicial" => "105" "paginaFinal" => "117" ] ] ] ] ] ] 12 => array:3 [ "identificador" => "bib0505" "etiqueta" => "[13]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Oxyfluoride glass-ceramics for transition metal Ion based photonics: broadband near-IR luminescence of nickel ion dopant and nanocrystallization mechanism" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Phys. Chem. C" "fecha" => "2016" "volumen" => "120" "paginaInicial" => "4556" "paginaFinal" => "4563" ] ] ] ] ] ] 13 => array:3 [ "identificador" => "bib0510" "etiqueta" => "[14]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Laser-related spectroscopy of ion-doped crystals for tunable solid-state lasers" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Appl. Phys. B" "fecha" => "2001" "volumen" => "72" "paginaInicial" => "515" "paginaFinal" => "562" ] ] ] ] ] ] 14 => array:3 [ "identificador" => "bib0515" "etiqueta" => "[15]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Photoluminescence of the Mg2Al4Si5O18–Al2O3–MgAl2O4–SiO2 ceramic system containing Fe3+ and Cr3+ as impurity ions" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Opt. Mater." "fecha" => "2018" "volumen" => "76" "paginaInicial" => "353" "paginaFinal" => "358" ] ] ] ] ] ] 15 => array:3 [ "identificador" => "bib0520" "etiqueta" => "[16]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Fe in III–V and II–VI semiconductors" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Phys. Stat. Sol. (b)" "fecha" => "2008" "volumen" => "245" "paginaInicial" => "455" "paginaFinal" => "480" ] ] ] ] ] ] 16 => array:3 [ "identificador" => "bib0525" "etiqueta" => "[17]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The effects of charge compensation on photoluminescence properties of a new green-emitting ZnB2O4:Tb3+ phosphor" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1002/bio.2634" "Revista" => array:6 [ "tituloSerie" => "Luminescence" "fecha" => "2014" "volumen" => "29" "paginaInicial" => "868" "paginaFinal" => "871" "link" => array:1 [ …1] ] ] ] ] ] ] 17 => array:3 [ "identificador" => "bib0530" "etiqueta" => "[18]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Excitonics of semiconductor quantum dots and wires for lighting and displays" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Laser Photon. Rev." "fecha" => "2014" "volumen" => "8" "paginaInicial" => "73" "paginaFinal" => "93" ] ] ] ] ] ] 18 => array:3 [ "identificador" => "bib0535" "etiqueta" => "[19]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Improved optical photoluminescence by charge compensation in the phosphor system CaMoO4:Eu3+" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Opt. Mater." "fecha" => "2007" "volumen" => "29" "paginaInicial" => "1591" "paginaFinal" => "1594" ] ] ] ] ] ] 19 => array:3 [ "identificador" => "bib0540" "etiqueta" => "[20]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Effects of charge compensation on the luminescence behaviour of Eu3+ activated CaWO4 phosphor" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Opt. Mater." "fecha" => "2008" "volumen" => "30" "paginaInicial" => "1616" "paginaFinal" => "1620" ] ] ] ] ] ] 20 => array:3 [ "identificador" => "bib0545" "etiqueta" => "[21]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Improved optical photoluminescence by charge compensation and luminescence tuning in Ca6Ba(PO4)4O:Ce3+, Eu2+ phosphors" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Cryst. Eng. Comm." "fecha" => "2015" "volumen" => "17" "paginaInicial" => "8632" "paginaFinal" => "8638" ] ] ] ] ] ] 21 => array:3 [ "identificador" => "bib0550" "etiqueta" => "[22]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Structural and photophysical investigations of bright yellow emitting Dy: ZnAl2O4 nanophosphor" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Lumin." "fecha" => "2016" "volumen" => "178" "paginaInicial" => "407" "paginaFinal" => "413" ] ] ] ] ] ] 22 => array:3 [ "identificador" => "bib0555" "etiqueta" => "[23]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Low temperature synthesis, structural and dosimetric characterization of ZnAl2O4:Ce3+ nanophosphor" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Spectrochim. Acta Part A" "fecha" => "2014" "volumen" => "122" "paginaInicial" => "489" "paginaFinal" => "498" ] ] ] ] ] ] 23 => array:3 [ "identificador" => "bib0560" "etiqueta" => "[24]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Sr- and Ni-doping in ZnO nanorods synthesized by a simple wet chemical method as excellent materials for CO and CO2 gas sensing" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "RSC Adv." "fecha" => "2016" "volumen" => "6" "paginaInicial" => "82733" "paginaFinal" => "82742" ] ] ] ] ] ] 24 => array:3 [ "identificador" => "bib0565" "etiqueta" => "[25]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Synthesis of Ni-doped ZnO nanostructures by low temperature wet chemical method and their enhanced field emission properties" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "RSC Adv." "fecha" => "2016" "volumen" => "6" "paginaInicial" => "104318" "paginaFinal" => "104324" ] ] ] ] ] ] 25 => array:3 [ "identificador" => "bib0570" "etiqueta" => "[26]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:1 [ "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:4 [ "tituloSerie" => "Acta Crystallogr., Sect. A: Cryst. Phys., Diffr. Theor. Gen. Cryst." "fecha" => "1976" "volumen" => "32" "paginaInicial" => "751" ] ] ] ] ] ] 26 => array:3 [ "identificador" => "bib0575" "etiqueta" => "[27]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "X-ray line broadening from filed aluminium and wolfram" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Acta Metall." "fecha" => "1953" "volumen" => "1" "paginaInicial" => "22" "paginaFinal" => "31" ] ] ] ] ] ] 27 => array:3 [ "identificador" => "bib0580" "etiqueta" => "[28]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Williamson–Hall analysis in estimation of lattice strain in nanometer-sized ZnO particles" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Theor. Appl. Phys." "fecha" => "2012" "volumen" => "6" "paginaInicial" => "6" "paginaFinal" => "13" ] ] ] ] ] ] 28 => array:3 [ "identificador" => "bib0585" "etiqueta" => "[29]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "X-ray Diffraction Crystallography" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Libro" => array:3 [ "fecha" => "2011" "paginaInicial" => "75" "editorial" => "Springer-Verlag Berlin Heidelberg" ] ] ] ] ] ] 29 => array:3 [ "identificador" => "bib0590" "etiqueta" => "[30]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The evidence for a miscibility gap in the Fe3O4–ZnFe2O4 system – a review" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Mater. Trans. B" "fecha" => "1988" "volumen" => "19" "paginaInicial" => "919" "paginaFinal" => "925" ] ] ] ] ] ] 30 => array:3 [ "identificador" => "bib0595" "etiqueta" => "[31]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Systematics of the spinel structure type" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Phys. Chem. Miner." "fecha" => "1979" "volumen" => "4" "paginaInicial" => "317" "paginaFinal" => "339" ] ] ] ] ] ] 31 => array:3 [ "identificador" => "bib0600" "etiqueta" => "[32]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "In-situ high-pressure X-ray diffraction study of zinc ferrite nanoparticles" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Solid State Sci." "fecha" => "2016" "volumen" => "56" "paginaInicial" => "68" "paginaFinal" => "72" ] ] ] ] ] ] 32 => array:3 [ "identificador" => "bib0605" "etiqueta" => "[33]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Biomineralization associated with microbial reduction of Fe3+ and oxidation of Fe2+ in solid minerals" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Am. Mineral." "fecha" => "2009" "volumen" => "94" "paginaInicial" => "1049" "paginaFinal" => "1058" ] ] ] ] ] ] 33 => array:3 [ "identificador" => "bib0610" "etiqueta" => "[34]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Vivianite and siderite in lateritic iron crust: an example of bioreduction" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Quim. Nova" "fecha" => "2007" "volumen" => "30" "paginaInicial" => "36" "paginaFinal" => "40" ] ] ] ] ] ] 34 => array:3 [ "identificador" => "bib0615" "etiqueta" => "[35]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Zn–O tetrahedral bond length variations in normal spinel oxides" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Am. Miner." "fecha" => "2011" "volumen" => "96" "paginaInicial" => "594" "paginaFinal" => "598" ] ] ] ] ] ] 35 => array:3 [ "identificador" => "bib0620" "etiqueta" => "[36]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Charge order at magnetite Fe3O4(001): surface and Verwey phase transitions" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1088/0953-8984/27/1/012001" "Revista" => array:6 [ "tituloSerie" => "J. Phys. Condens. Matter" "fecha" => "2015" "volumen" => "27" "paginaInicial" => "012001" "paginaFinal" => "012008" "link" => array:1 [ …1] ] ] ] ] ] ] 36 => array:3 [ "identificador" => "bib0625" "etiqueta" => "[37]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "ImageJ User Guide" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Libro" => array:1 [ "fecha" => "2012" ] ] ] ] ] ] 37 => array:3 [ "identificador" => "bib0630" "etiqueta" => "[38]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Correlations between crystallite/particle size and photoluminescence properties of submicrometer phosphors" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Chem. Mater." "fecha" => "2007" "volumen" => "19" "paginaInicial" => "1723" "paginaFinal" => "1730" ] ] ] ] ] ] 38 => array:3 [ "identificador" => "bib0635" "etiqueta" => "[39]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Correlation between particle size/domain structure and magnetic properties of highly crystalline Fe3O4 nanoparticles" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1038/s41598-017-09897-5" "Revista" => array:6 [ "tituloSerie" => "Sci. Rep." "fecha" => "2017" "volumen" => "7" "paginaInicial" => "9894" "paginaFinal" => "98911" "link" => array:1 [ …1] ] ] ] ] ] ] 39 => array:3 [ "identificador" => "bib0640" "etiqueta" => "[40]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Structural characterization of Gd2O3 phosphor synthesized by solid state reaction and combustion method using X-ray diffraction and transmission electron microscopic techniques" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Display Technol." "fecha" => "2016" "volumen" => "12" "paginaInicial" => "921" "paginaFinal" => "927" ] ] ] ] ] ] 40 => array:3 [ "identificador" => "bib0645" "etiqueta" => "[41]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Mechanical Alloying and Milling" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Libro" => array:4 [ "fecha" => "2014" "paginaInicial" => "333" "editorial" => "Marcel Dekker" "editorialLocalizacion" => "NY" ] ] ] ] ] ] 41 => array:3 [ "identificador" => "bib0650" "etiqueta" => "[42]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Chemical imaging analysis" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "LibroEditado" => array:5 [ "paginaInicial" => "269" "paginaFinal" => "313" "serieVolumen" => "vol. 69" "serieTitulo" => "Comprehensive Analytical Chemistry" "serieFecha" => "2015" ] ] ] ] ] ] 42 => array:3 [ "identificador" => "bib0655" "etiqueta" => "[43]" "referencia" => array:1 [ 0 => array:1 [ "referenciaCompleta" => "Royal Society of Chemistry, X-ray photoelectron spectroscopy, <a target="_blank" href="https://www.rsc.org/publishing/journals/prospect/ontology.asp?id=CMO:0000404%26MSID=B602486F">https://www.rsc.org/publishing/journals/prospect/ontology.asp?id=CMO:0000404&MSID=B602486F</a> (May 2019)." ] ] ] 43 => array:3 [ "identificador" => "bib0660" "etiqueta" => "[44]" "referencia" => array:1 [ 0 => array:1 [ "referenciaCompleta" => "Operator's PHI MULTIPAK Software Manual, Version 8.2C, Ulvac-PHI, Inc., Chigasaki City, Kanagawa Prefecture, Japan, 2007." ] ] ] 44 => array:3 [ "identificador" => "bib0665" "etiqueta" => "[45]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Luminescence characterization and electron beam induced chemical changes on the surface of ZnAl2O4:Mn nanocrystalline phosphor" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Appl. Surf. Sci." "fecha" => "2011" "volumen" => "257" "paginaInicial" => "3298" "paginaFinal" => "3306" ] ] ] ] ] ] 45 => array:3 [ "identificador" => "bib0670" "etiqueta" => "[46]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "A photochemical proposal for the preparation of ZnAl2O4 and MgAl2O4 thin films from beta-diketonate complex precursors" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Mater. Res. Bull." "fecha" => "2016" "volumen" => "77" "paginaInicial" => "212" "paginaFinal" => "220" ] ] ] ] ] ] 46 => array:3 [ "identificador" => "bib0675" "etiqueta" => "[47]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Enhanced green emission from UV down-converting Ce3+–Tb3+ co-activated ZnAl2O4 phosphor" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Vac. Sci. Technol. B" "fecha" => "2012" "volumen" => "30" "paginaInicial" => "031401" "paginaFinal" => "031407" ] ] ] ] ] ] 47 => array:3 [ "identificador" => "bib0680" "etiqueta" => "[48]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Low-symmetry mesoporous titanium dioxide (lsm-TiO2) electrocatalyst for efficient and durable oxygen evolution in aqueous alkali" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Electrochem. Soc." "fecha" => "2018" "volumen" => "165" "paginaInicial" => "H300" "paginaFinal" => "H309" ] ] ] ] ] ] 48 => array:3 [ "identificador" => "bib0685" "etiqueta" => "[49]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Luminescent properties and X-ray photoelectron spectroscopy study of ZnAl2O4:Ce3+,Tb3+ phosphor" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Alloys Compd." "fecha" => "2011" "volumen" => "509" "paginaInicial" => "10115" "paginaFinal" => "10120" ] ] ] ] ] ] 49 => array:3 [ "identificador" => "bib0690" "etiqueta" => "[50]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "ESCA studies of yttrium aluminum garnets" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Phys. Chem. B" "fecha" => "1999" "volumen" => "103" "paginaInicial" => "1454" "paginaFinal" => "1461" ] ] ] ] ] ] 50 => array:3 [ "identificador" => "bib0695" "etiqueta" => "[51]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The influence of process parameters and pulse ratio of precursors on the characteristics of La1−xAlxO3 films deposited by atomic layer deposition" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1186/s11671-015-0883-6" "Revista" => array:6 [ "tituloSerie" => "Nanoscale Res. Lett." "fecha" => "2015" "volumen" => "10" "paginaInicial" => "180" "paginaFinal" => "189" "link" => array:1 [ …1] ] ] ] ] ] ] 51 => array:3 [ "identificador" => "bib0700" "etiqueta" => "[52]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Enhanced ammonia dehydrogenation over Ru/La(x)–Al2O3 (x=0–50mol%): structural and electronic effects of La doping" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Int. J. Hydrogen Energy" "fecha" => "2017" "volumen" => "42" "paginaInicial" => "1639" "paginaFinal" => "1647" ] ] ] ] ] ] 52 => array:3 [ "identificador" => "bib0705" "etiqueta" => "[53]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The support effects on the direct conversion of syngas to higher alcohol synthesis over copper-based catalysts" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Catalysts" "fecha" => "2019" "volumen" => "9" "paginaInicial" => "199" "paginaFinal" => "2016" ] ] ] ] ] ] 53 => array:3 [ "identificador" => "bib0710" "etiqueta" => "[54]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Plasma-assisted hot filament chemical vapor deposition of AlN thin films on ZnO buffer layer: toward highly c-axis-oriented, uniform, insulative films" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Appl. Phys. A" "fecha" => "2014" "volumen" => "117" "paginaInicial" => "2217" "paginaFinal" => "2224" ] ] ] ] ] ] 54 => array:3 [ "identificador" => "bib0715" "etiqueta" => "[55]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Novel polyelectrolyte–Al2O3/SiO2 composite nanoabrasives for improved chemical mechanical polishing (CMP) of sapphire" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Mater. Res." "fecha" => "2019" "volumen" => "34" "paginaInicial" => "1073" "paginaFinal" => "1082" ] ] ] ] ] ] 55 => array:3 [ "identificador" => "bib0720" "etiqueta" => "[56]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Inorganic Nanostructures" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Libro" => array:4 [ "fecha" => "2012" "paginaInicial" => "41" "editorial" => "Wiley-VCH Verlag & Co. KGaA" "editorialLocalizacion" => "Weinheim, Germany" ] ] ] ] ] ] 56 => array:3 [ "identificador" => "bib0725" "etiqueta" => "[57]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Influence of annealing environment on the ALD-Al2O3/4H–SiC interface" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Phys. D: Appl. Phys." "fecha" => "2018" "volumen" => "51" "paginaInicial" => "105111" "paginaFinal" => "105127" ] ] ] ] ] ] 57 => array:3 [ "identificador" => "bib0730" "etiqueta" => "[58]" "referencia" => array:1 [ 0 => array:1 [ "referenciaCompleta" => "T. Helmenstine, List of electronegativity values of the elements, <a target="_blank" href="https://sciencenotes.org/list-of-electronegativity-values-of-the-elements/">https://sciencenotes.org/list-of-electronegativity-values-of-the-elements/</a> (June 2019)." ] ] ] 58 => array:3 [ "identificador" => "bib0735" "etiqueta" => "[59]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Influence of inversion defects and Cr–Cr pairs on the photoluminescent performance of ZnAl2O4 crystals" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Sol–Gel Sci. Technol." "fecha" => "2018" "volumen" => "85" "paginaInicial" => "121" "paginaFinal" => "131" ] ] ] ] ] ] 59 => array:3 [ "identificador" => "bib0740" "etiqueta" => "[60]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Surface smoothing and native oxide suppression on Zn doped aerotaxy GaAs nanowires" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Appl. Phys." "fecha" => "2019" "volumen" => "125" "paginaInicial" => "025303" "paginaFinal" => "0253011" ] ] ] ] ] ] 60 => array:3 [ "identificador" => "bib0745" "etiqueta" => "[61]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Localized nano-solid-solution induced by Cu doping in ZnS for efficient solar hydrogen generation" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1039/c4dt00969j" "Revista" => array:6 [ "tituloSerie" => "Dalton Trans." "fecha" => "2014" "volumen" => "43" "paginaInicial" => "11533" "paginaFinal" => "11541" "link" => array:1 [ …1] ] ] ] ] ] ] 61 => array:3 [ "identificador" => "bib0750" "etiqueta" => "[62]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Relationship between ferromagnetism and formation of complex carbon bonds in carbon doped ZnO powders" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1039/c9cp01277j" "Revista" => array:6 [ "tituloSerie" => "Phys. Chem. Chem. Phys." "fecha" => "2019" "volumen" => "21" "paginaInicial" => "8808" "paginaFinal" => "8819" "link" => array:1 [ …1] ] ] ] ] ] ] 62 => array:3 [ "identificador" => "bib0755" "etiqueta" => "[63]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Improvement of structural and optical properties of ZnAl2O4:Cr3+ ceramics with surface modification by using various concentrations of zinc acetate" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Sol–Gel Sci. Technol." "fecha" => "2018" "volumen" => "88" "paginaInicial" => "422" "paginaFinal" => "429" ] ] ] ] ] ] 63 => array:3 [ "identificador" => "bib0760" "etiqueta" => "[64]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Structural, elemental, optical and magnetic study of Fe doped ZnO and impurity phase formation" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Proc. Nat. Sci. Mater." "fecha" => "2014" "volumen" => "24" "paginaInicial" => "142" "paginaFinal" => "149" ] ] ] ] ] ] 64 => array:3 [ "identificador" => "bib0765" "etiqueta" => "[65]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Tuning the surface anisotropy in Fe-doped NiO nanoparticles" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Nanoscale" "fecha" => "2014" "volumen" => "6" "paginaInicial" => "352" "paginaFinal" => "357" ] ] ] ] ] ] 65 => array:3 [ "identificador" => "bib0770" "etiqueta" => "[66]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Analysis of XPS spectra of Fe2+ and Fe3+ ions in oxide materials" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Appl. Surf. Sci." "fecha" => "2008" "volumen" => "254" "paginaInicial" => "2441" "paginaFinal" => "2449" ] ] ] ] ] ] 66 => array:3 [ "identificador" => "bib0775" "etiqueta" => "[67]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Electrodeposition and characterization of ZnX (X=Se, Te) semiconductor thin films" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:4 [ "tituloSerie" => "Bol. Soc. Chil. Quím." "fecha" => "2002" "volumen" => "47" "paginaInicial" => "411" ] ] ] ] ] ] 67 => array:3 [ "identificador" => "bib0780" "etiqueta" => "[68]" "referencia" => array:1 [ 0 => array:1 [ "host" => array:1 [ 0 => array:1 [ "LibroEditado" => array:3 [ "editores" => "J.Tauc" "titulo" => "The Optical Properties of Solids" "serieFecha" => "1966" ] ] ] ] ] ] 68 => array:3 [ "identificador" => "bib0785" "etiqueta" => "[69]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Electronic structure of spinel oxides: zinc aluminate and zinc gallate" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Phys. Condens. Matter" "fecha" => "1999" "volumen" => "11" "paginaInicial" => "3635" "paginaFinal" => "3644" ] ] ] ] ] ] 69 => array:3 [ "identificador" => "bib0790" "etiqueta" => "[70]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Full-potential calculations of structural, elastic and electronic properties of MgAl2O4 and ZnAl2O4 compounds" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Phys. Lett. A" "fecha" => "2005" "volumen" => "344" "paginaInicial" => "271" "paginaFinal" => "279" ] ] ] ] ] ] 70 => array:3 [ "identificador" => "bib0795" "etiqueta" => "[71]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Synthesis and characterization studies of ZnFe2O4 nanoparticles" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "MMSE" "fecha" => "2017" "volumen" => "9" "paginaInicial" => "13" "paginaFinal" => "17" ] ] ] ] ] ] 71 => array:3 [ "identificador" => "bib0800" "etiqueta" => "[72]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Photodegradation of rhodamine B by using ZnFe2O4 nanoparticles synthesized through precipitation method" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:4 [ "tituloSerie" => "IOP Conf. Ser. Mater. Sci. Eng." "fecha" => "2017" "volumen" => "202" "paginaInicial" => "012044" ] ] ] ] ] ] 72 => array:3 [ "identificador" => "bib0805" "etiqueta" => "[73]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Reflectance Spectroscopy" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Libro" => array:5 [ "fecha" => "1969" "paginaInicial" => "103" "paginaFinal" => "169" "editorial" => "Springer-Verlag" "editorialLocalizacion" => "New York" ] ] ] ] ] ] 73 => array:3 [ "identificador" => "bib0810" "etiqueta" => "[74]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Tight-binding theory of heterojunction band lineups and interface dipoles" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Vac. Sci. Technol. B" "fecha" => "1986" "volumen" => "4" "paginaInicial" => "1068" "paginaFinal" => "1073" ] ] ] ] ] ] 74 => array:3 [ "identificador" => "bib0815" "etiqueta" => "[75]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Intense photoluminescence of slightly doped ZnO–SiO2 matrix" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Chem. Phys. Lett." "fecha" => "2006" "volumen" => "425" "paginaInicial" => "77" "paginaFinal" => "81" ] ] ] ] ] ] 75 => array:3 [ "identificador" => "bib0820" "etiqueta" => "[76]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Single-source sol–gel synthesis of nanocrystalline ZnAl2O4: structural and optical properties" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Am. Ceram. Soc." "fecha" => "2001" "volumen" => "84" "paginaInicial" => "1921" "paginaFinal" => "1928" ] ] ] ] ] ] 76 => array:3 [ "identificador" => "bib0825" "etiqueta" => "[77]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "The role of surface Zn2+ ions in the transesterification of vegetable oils over ZnO supported on Al2O3 and Fe2O3" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Catal. Sci. Technol." "fecha" => "2014" "volumen" => "4" "paginaInicial" => "851" "paginaFinal" => "860" ] ] ] ] ] ] 77 => array:3 [ "identificador" => "bib0830" "etiqueta" => "[78]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Formation of complete solid solutions, Zn(AlxGa1−x)2O4 spinel nanocrystals via hydrothermal route" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Ceram. Int." "fecha" => "2014" "volumen" => "40" "paginaInicial" => "15841" "paginaFinal" => "15848" ] ] ] ] ] ] 78 => array:3 [ "identificador" => "bib0835" "etiqueta" => "[79]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Effect of heat-treatment and composition on structure and luminescence properties of spinel-type solid solution nanocrystals" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1166/jnn.2015.10272" "Revista" => array:6 [ "tituloSerie" => "J. Nanosci. Nanotechnol." "fecha" => "2015" "volumen" => "15" "paginaInicial" => "6069" "paginaFinal" => "6077" "link" => array:1 [ …1] ] ] ] ] ] ] 79 => array:3 [ "identificador" => "bib0840" "etiqueta" => "[80]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "ZnAl2O4 as a potential sensor: variation of luminescence with thermal history" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Mater. Chem. C" "fecha" => "2013" "volumen" => "1" "paginaInicial" => "5419" "paginaFinal" => "5428" ] ] ] ] ] ] 80 => array:3 [ "identificador" => "bib0845" "etiqueta" => "[81]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Photoluminescence and photoacoustic spectroscopies of Fe3+ in the LiGa5O8–LiGaSiO4–Li5GaSi2O8 system" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1007/s10895-008-0404-4" "Revista" => array:6 [ "tituloSerie" => "J. Fluoresc." "fecha" => "2009" "volumen" => "19" "paginaInicial" => "211" "paginaFinal" => "219" "link" => array:1 [ …1] ] ] ] ] ] ] 81 => array:3 [ "identificador" => "bib0850" "etiqueta" => "[82]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Synthesis and luminescence characteristics of Dy3+ doped KLa(PO3)4" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Lumin." "fecha" => "2015" "volumen" => "166" "paginaInicial" => "82" "paginaFinal" => "87" ] ] ] ] ] ] 82 => array:3 [ "identificador" => "bib0855" "etiqueta" => "[83]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Emerging ultra-narrow-band cyan-emitting phosphor for white LEDs with enhanced color rendition" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1038/s41377-019-0148-8" "Revista" => array:6 [ "tituloSerie" => "Light-Sci. Appl." "fecha" => "2019" "volumen" => "8" "paginaInicial" => "38" "paginaFinal" => "47" "link" => array:1 [ …1] ] ] ] ] ] ] 83 => array:3 [ "identificador" => "bib0860" "etiqueta" => "[84]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Transition metal-doped chalcogenide glasses for broadband near-infrared sources" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "LibroEditado" => array:5 [ "paginaInicial" => "289" "paginaFinal" => "296" "serieVolumen" => "vol. 5620" "serieTitulo" => "Solid State Laser Technologies and Femtosecond Phenomena" "serieFecha" => "2004" ] ] ] ] ] ] 84 => array:3 [ "identificador" => "bib0865" "etiqueta" => "[85]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Interpretation of the changing the band gap of Al2O3 depending on its crystalline form: connection with different local symmetries" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "J. Phys. Chem. C" "fecha" => "2015" "volumen" => "119" "paginaInicial" => "20755" "paginaFinal" => "20761" ] ] ] ] ] ] 85 => array:3 [ "identificador" => "bib0870" "etiqueta" => "[86]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Charge-transfer transitions and pseudoacceptor states of iron in gallium phosphide" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ "tituloSerie" => "Phys. Rev. B" "fecha" => "1993" "volumen" => "47" "paginaInicial" => "16267" "paginaFinal" => "16273" ] ] ] ] ] ] 86 => array:3 [ "identificador" => "bib0875" "etiqueta" => "[87]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Photoluminescence and photothermal effect of Fe3O4 nanoparticles for medical imaging and therapy" "autores" => array:1 [ 0 => array:2 [ …2] ] ] ] "host" => array:1 [ 0 => array:1 [ "Revista" => array:5 [ …5] ] ] ] ] ] 87 => array:3 [ "identificador" => "bib0880" "etiqueta" => "[88]" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Nanoscale analyses applied to nanowire devices" "autores" => array:1 [ …1] ] ] "host" => array:1 [ 0 => array:1 [ "LibroEditado" => array:5 [ …5] ] ] ] ] ] ] ] ] ] "agradecimientos" => array:1 [ 0 => array:4 [ "identificador" => "xack535380" "titulo" => "Acknowledgements" "texto" => "The authors express their sincere thanks to the South African Research Chairs Initiative of the Department of Science and Technology and the National Research Foundation of South Africa (84415). The financial assistance from the University of the Free State, South Africa is highly recognized." "vista" => "all" ] ] ] "idiomaDefecto" => "en" "url" => "/03663175/0000006000000003/v2_202106110717/S0366317520300297/v2_202106110717/en/main.assets" "Apartado" => null "PDF" => "https://static.elsevier.es/multimedia/03663175/0000006000000003/v2_202106110717/S0366317520300297/v2_202106110717/en/main.pdf?idApp=UINPBA00004N&text.app=https://www.elsevier.es/" "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S0366317520300297?idApp=UINPBA00004N"]

Statistics

Original

Luminescence, structure and insight on the inversion degree from normal to inverse spinel in a ZnAl(2−x)Fex3+O4 system

Luminiscencia, estructura e información sobre el grado de inversión de la espinela normal a la inversa en un sistema ZnAl(2−x)Fex3+O4

Simon N. Oguguaa,

Corresponding author

Oguason@yahoo.com

Corresponding author.

, Odireleng M. Ntwaeaborwab, Hendrik C. Swarta

a Department of Physics, University of the Free State, Bloemfontein ZA-9300, South Africa

b School of Physics, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa

Read

7895

Times
was read the article

1548

Total PDF

6347

Total HTML

Share statistics

 array:24 [
  "pii" => "S0366317520300297"
  "issn" => "03663175"
  "doi" => "10.1016/j.bsecv.2020.02.005"
  "estado" => "S300"
  "fechaPublicacion" => "2021-05-01"
  "aid" => "211"
  "copyright" => "SECV"
  "copyrightAnyo" => "2020"
  "documento" => "article"
  "crossmark" => 1
  "licencia" => "http://creativecommons.org/licenses/by-nc-nd/4.0/"
  "subdocumento" => "fla"
  "cita" => "Bol Soc Esp Ceram Vidr. 2021;60:147-62"
  "abierto" => array:3 [
    "ES" => true
    "ES2" => true
    "LATM" => true
  ]
  "gratuito" => true
  "lecturas" => array:1 [
    "total" => 0
  ]
  "itemSiguiente" => array:19 [
    "pii" => "S0366317520300200"
    "issn" => "03663175"
    "doi" => "10.1016/j.bsecv.2020.01.012"
    "estado" => "S300"
    "fechaPublicacion" => "2021-05-01"
    "aid" => "202"
    "copyright" => "SECV"
    "documento" => "article"
    "crossmark" => 1
    "licencia" => "http://creativecommons.org/licenses/by-nc-nd/4.0/"
    "subdocumento" => "fla"
    "cita" => "Bol Soc Esp Ceram Vidr. 2021;60:163-74"
    "abierto" => array:3 [
      "ES" => true
      "ES2" => true
      "LATM" => true
    ]
    "gratuito" => true
    "lecturas" => array:1 [
      "total" => 0
    ]
    "en" => array:13 [
      "idiomaDefecto" => true
      "cabecera" => "<span class="elsevierStyleTextfn">Original</span>"
      "titulo" => "Use of mechanical activation to obtain Mg&#40;OH&#41;<span class="elsevierStyleInf">2</span> from olivine mineral for CO<span class="elsevierStyleInf">2</span> capture"
      "tienePdf" => "en"
      "tieneTextoCompleto" => "en"
      "tieneResumen" => array:2 [
        0 => "en"
        1 => "es"
      ]
      "paginas" => array:1 [
        0 => array:2 [
          "paginaInicial" => "163"
          "paginaFinal" => "174"
        ]
      ]
      "titulosAlternativos" => array:1 [
        "es" => array:1 [
          "titulo" => "Uso de la activaci&#243;n mec&#225;nica para obtener Mg&#40;OH&#41;<span class="elsevierStyleInf">2</span> del mineral de olivino para la captura de CO<span class="elsevierStyleInf">2</span>"
        ]
      ]
      "contieneResumen" => array:2 [
        "en" => true
        "es" => true
      ]
      "contieneTextoCompleto" => array:1 [
        "en" => true
      ]
      "contienePdf" => array:1 [
        "en" => true
      ]
      "resumenGrafico" => array:2 [
        "original" => 0
        "multimedia" => array:7 [
          "identificador" => "fig0080"
          "etiqueta" => "Fig&#46; 16"
          "tipo" => "MULTIMEDIAFIGURA"
          "mostrarFloat" => true
          "mostrarDisplay" => false
          "figura" => array:1 [
            0 => array:4 [
              "imagen" => "gr16.jpeg"
              "Alto" => 1179
              "Ancho" => 1591
              "Tamanyo" => 123158
            ]
          ]
          "descripcion" => array:1 [
            "en" => "<p id="spar0090" class="elsevierStyleSimplePara elsevierViewall">TGA and DTA curves of hydromagnesite after CO<span class="elsevierStyleInf">2</span> absorption at 200<span class="elsevierStyleHsp" style=""></span>&#176;C&#47;24<span class="elsevierStyleHsp" style=""></span>h&#46;</p>"
          ]
        ]
      ]
      "autores" => array:1 [
        0 => array:2 [
          "autoresLista" => "Claudia Maribel Garc&#237;a-Hern&#225;ndez, Jorge L&#243;pez-Cuevas, Carlos Alberto Guti&#233;rrez-Chavarr&#237;a, Alfredo Flores-Vald&#233;s"
          "autores" => array:4 [
            0 => array:2 [
              "nombre" => "Claudia Maribel"
              "apellidos" => "Garc&#237;a-Hern&#225;ndez"
            ]
            1 => array:2 [
              "nombre" => "Jorge"
              "apellidos" => "L&#243;pez-Cuevas"
            ]
            2 => array:2 [
              "nombre" => "Carlos Alberto"
              "apellidos" => "Guti&#233;rrez-Chavarr&#237;a"
            ]
            3 => array:2 [
              "nombre" => "Alfredo"
              "apellidos" => "Flores-Vald&#233;s"
            ]
          ]
        ]
      ]
    ]
    "idiomaDefecto" => "en"
    "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S0366317520300200?idApp=UINPBA00004N"
    "url" => "/03663175/0000006000000003/v2_202106110717/S0366317520300200/v2_202106110717/en/main.assets"
  ]
  "itemAnterior" => array:19 [
    "pii" => "S0366317520300339"
    "issn" => "03663175"
    "doi" => "10.1016/j.bsecv.2020.03.006"
    "estado" => "S300"
    "fechaPublicacion" => "2021-05-01"
    "aid" => "215"
    "copyright" => "SECV"
    "documento" => "article"
    "crossmark" => 1
    "licencia" => "http://creativecommons.org/licenses/by-nc-nd/4.0/"
    "subdocumento" => "fla"
    "cita" => "Bol Soc Esp Ceram Vidr. 2021;60:138-46"
    "abierto" => array:3 [
      "ES" => true
      "ES2" => true
      "LATM" => true
    ]
    "gratuito" => true
    "lecturas" => array:1 [
      "total" => 0
    ]
    "en" => array:13 [
      "idiomaDefecto" => true
      "cabecera" => "<span class="elsevierStyleTextfn">Original</span>"
      "titulo" => "Tuning Ca<span class="elsevierStyleInf">3</span>Co<span class="elsevierStyleInf">4</span>O<span class="elsevierStyleInf">9</span> thermal and transport properties by TiC nanoparticles addition"
      "tienePdf" => "en"
      "tieneTextoCompleto" => "en"
      "tieneResumen" => array:2 [
        0 => "en"
        1 => "es"
      ]
      "paginas" => array:1 [
        0 => array:2 [
          "paginaInicial" => "138"
          "paginaFinal" => "146"
        ]
      ]
      "titulosAlternativos" => array:1 [
        "es" => array:1 [
          "titulo" => "Ajuste de propiedades t&#233;rmicas y el&#233;ctricas del Ca<span class="elsevierStyleInf">3</span>Co<span class="elsevierStyleInf">4</span>O<span class="elsevierStyleInf">9</span> por medio de adici&#243;n de nanopart&#237;culas de TiC"
        ]
      ]
      "contieneResumen" => array:2 [
        "en" => true
        "es" => true
      ]
      "contieneTextoCompleto" => array:1 [
        "en" => true
      ]
      "contienePdf" => array:1 [
        "en" => true
      ]
      "resumenGrafico" => array:2 [
        "original" => 0
        "multimedia" => array:7 [
          "identificador" => "fig0015"
          "etiqueta" => "Fig&#46; 3"
          "tipo" => "MULTIMEDIAFIGURA"
          "mostrarFloat" => true
          "mostrarDisplay" => false
          "figura" => array:1 [
            0 => array:4 [
              "imagen" => "gr3.jpeg"
              "Alto" => 1688
              "Ancho" => 1625
              "Tamanyo" => 169746
            ]
          ]
          "descripcion" => array:1 [
            "en" => "<p id="spar0025" class="elsevierStyleSimplePara elsevierViewall">Enlarged view of the &#40;002&#41; diffraction peak in the Ca<span class="elsevierStyleInf">3</span>Co<span class="elsevierStyleInf">4</span>O<span class="elsevierStyleInf">9</span><span class="elsevierStyleHsp" style=""></span>&#43;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleItalic">x</span> wt&#46;&#37; TiC samples&#59; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;00 &#40;a&#41;&#59; 0&#46;25 &#40;b&#41;&#59; 0&#46;50 &#40;c&#41;&#59; 0&#46;75 &#40;d&#41;&#59; and 1&#46;0 &#40;e&#41;&#46;</p>"
          ]
        ]
      ]
      "autores" => array:1 [
        0 => array:2 [
          "autoresLista" => "H&#46; Amaveda, O&#46;J&#46; Dura, M&#46; Mora, M&#46;A&#46; Torres, G&#46; Guelou, M&#46;A&#46; Madre, S&#46; Marinel, A&#46; Sotelo"
          "autores" => array:8 [
            0 => array:2 [
              "nombre" => "H&#46;"
              "apellidos" => "Amaveda"
            ]
            1 => array:2 [
              "nombre" => "O&#46;J&#46;"
              "apellidos" => "Dura"
            ]
            2 => array:2 [
              "nombre" => "M&#46;"
              "apellidos" => "Mora"
            ]
            3 => array:2 [
              "nombre" => "M&#46;A&#46;"
              "apellidos" => "Torres"
            ]
            4 => array:2 [
              "nombre" => "G&#46;"
              "apellidos" => "Guelou"
            ]
            5 => array:2 [
              "nombre" => "M&#46;A&#46;"
              "apellidos" => "Madre"
            ]
            6 => array:2 [
              "nombre" => "S&#46;"
              "apellidos" => "Marinel"
            ]
            7 => array:2 [
              "nombre" => "A&#46;"
              "apellidos" => "Sotelo"
            ]
          ]
        ]
      ]
    ]
    "idiomaDefecto" => "en"
    "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S0366317520300339?idApp=UINPBA00004N"
    "url" => "/03663175/0000006000000003/v2_202106110717/S0366317520300339/v2_202106110717/en/main.assets"
  ]
  "en" => array:20 [
    "idiomaDefecto" => true
    "cabecera" => "<span class="elsevierStyleTextfn">Original</span>"
    "titulo" => "Luminescence&#44; structure and insight on the inversion degree from normal to inverse spinel in a ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> system"
    "tieneTextoCompleto" => true
    "paginas" => array:1 [
      0 => array:2 [
        "paginaInicial" => "147"
        "paginaFinal" => "162"
      ]
    ]
    "autores" => array:1 [
      0 => array:4 [
        "autoresLista" => "Simon N&#46; Ogugua, Odireleng M&#46; Ntwaeaborwa, Hendrik C&#46; Swart"
        "autores" => array:3 [
          0 => array:4 [
            "nombre" => "Simon N&#46;"
            "apellidos" => "Ogugua"
            "email" => array:1 [
              0 => "Oguason@yahoo.com"
            ]
            "referencia" => array:2 [
              0 => array:2 [
                "etiqueta" => "<span class="elsevierStyleSup">a</span>"
                "identificador" => "aff0005"
              ]
              1 => array:2 [
                "etiqueta" => "<span class="elsevierStyleSup">&#42;</span>"
                "identificador" => "cor0005"
              ]
            ]
          ]
          1 => array:3 [
            "nombre" => "Odireleng M&#46;"
            "apellidos" => "Ntwaeaborwa"
            "referencia" => array:1 [
              0 => array:2 [
                "etiqueta" => "<span class="elsevierStyleSup">b</span>"
                "identificador" => "aff0010"
              ]
            ]
          ]
          2 => array:3 [
            "nombre" => "Hendrik C&#46;"
            "apellidos" => "Swart"
            "referencia" => array:1 [
              0 => array:2 [
                "etiqueta" => "<span class="elsevierStyleSup">a</span>"
                "identificador" => "aff0005"
              ]
            ]
          ]
        ]
        "afiliaciones" => array:2 [
          0 => array:3 [
            "entidad" => "Department of Physics&#44; University of the Free State&#44; Bloemfontein ZA-9300&#44; South Africa"
            "etiqueta" => "a"
            "identificador" => "aff0005"
          ]
          1 => array:3 [
            "entidad" => "School of Physics&#44; University of the Witwatersrand&#44; Private Bag 3&#44; Wits 2050&#44; South Africa"
            "etiqueta" => "b"
            "identificador" => "aff0010"
          ]
        ]
        "correspondencia" => array:1 [
          0 => array:3 [
            "identificador" => "cor0005"
            "etiqueta" => "&#8270;"
            "correspondencia" => "<span class="elsevierStyleItalic">Corresponding author</span>&#46;"
          ]
        ]
      ]
    ]
    "titulosAlternativos" => array:1 [
      "es" => array:1 [
        "titulo" => "Luminiscencia&#44; estructura e informaci&#243;n sobre el grado de inversi&#243;n de la espinela normal a la inversa en un sistema ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>"
      ]
    ]
    "resumenGrafico" => array:2 [
      "original" => 0
      "multimedia" => array:7 [
        "identificador" => "fig0080"
        "etiqueta" => "Fig&#46; 16"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr16.jpeg"
            "Alto" => 950
            "Ancho" => 1341
            "Tamanyo" => 116270
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0090" class="elsevierStyleSimplePara elsevierViewall">The PL emission spectra of &#40;a&#41; Zn<span class="elsevierStyleInf">&#40;1&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and &#40;b&#41; ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> for <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05&#44; excited at 235<span class="elsevierStyleHsp" style=""></span>nm&#46;</p>"
        ]
      ]
    ]
    "textoCompleto" => "<span class="elsevierStyleSections"><span id="sec0005" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0025">Introduction</span><p id="par0005" class="elsevierStylePara elsevierViewall">A spinel unit cell contains 8 face-centered cubics &#40;FCC&#41; cells&#46; Spinels are made up of an anion&#44; occupying the FCC lattice points&#44; forming octahedral &#40;oct&#41; and tetrahedral &#40;tet&#41; sites with two central metal ions&#44; usually divalent and trivalent ions&#44; respectively <a class="elsevierStyleCrossRef" href="#bib0445">&#91;1&#93;</a>&#46; They are represented by a general formula AB<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#44; where &#8220;A<span class="elsevierStyleSup">2&#43;&#8221;</span> is a divalent metal ion occupying the tet sites and &#8220;B<span class="elsevierStyleSup">3&#43;&#8221;</span> is a trivalent metal ion occupying the oct sites&#46; Spinels belong to the <span class="elsevierStyleItalic">F</span>&#8722;<span class="elsevierStyleItalic">d3m</span> space group&#46; Each unit cell contains 32 oxygen &#40;O<span class="elsevierStyleSup">2&#8722;</span>&#41; atoms&#44; with 8 &#8220;A<span class="elsevierStyleSup">2&#43;&#8221;</span> atoms and 16 &#8220;B<span class="elsevierStyleSup">3&#43;&#8221;</span> atoms&#46; Depending on the distribution of the &#8220;A<span class="elsevierStyleSup">2&#43;&#8221;</span> and &#8220;B<span class="elsevierStyleSup">3&#43;&#8221;</span> ions in the unit cell&#44; spinels are divided into normal and inverse&#46; Normal spinels have a cubic closed-packed &#40;ccp&#41; structure with more &#8220;B<span class="elsevierStyleSup">3&#43;&#8221;</span> ions than &#8220;A<span class="elsevierStyleSup">2&#43;&#8221;</span> ions&#46; The &#8220;A<span class="elsevierStyleSup">2&#43;&#8221;</span> ions occupying <span class="elsevierStyleSup">1</span>&#47;<span class="elsevierStyleInf">8</span> of the tet sites and the &#8220;B<span class="elsevierStyleSup">3&#43;&#8221;</span> ions occupying &#189; of the oct sites&#46; Atomic arrangement in the inverse spinel is such that the whole A<span class="elsevierStyleSup">2&#43;</span> ions and &#189; of the B<span class="elsevierStyleSup">3&#43;</span> ions occupy the oct sites&#44; while the other &#189; of the B<span class="elsevierStyleSup">3&#43;</span> ions occupy the tet sites&#46; Furthermore&#44; there is an intermediate structural arrangement described by the formula &#40;A<span class="elsevierStyleInf">1&#8722;<span class="elsevierStyleItalic">y</span></span>B<span class="elsevierStyleInf"><span class="elsevierStyleItalic">y</span></span>&#41; &#91;A<span class="elsevierStyleInf"><span class="elsevierStyleItalic">y</span>&#47;2</span>B<span class="elsevierStyleInf">1&#8722;<span class="elsevierStyleItalic">y</span>&#47;2</span>&#93;<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> with the terms in parentheses and square brackets denoting the tet and oct sites&#44; respectively&#46; <span class="elsevierStyleItalic">y</span> is called the inversion degree&#44; and its values range from 0&#44; for normal structure&#44; and 1&#44; for inverse structure&#44; and <span class="elsevierStyleSup">2</span>&#47;<span class="elsevierStyleInf">3</span> for random ion distribution <a class="elsevierStyleCrossRef" href="#bib0450">&#91;2&#93;</a>&#46;</p><p id="par0010" class="elsevierStylePara elsevierViewall">ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> belong to the spinel group known as the spinel-aluminate family&#46; It is naturally available in a mineral called gahnite&#46; ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> has almost normal spinel structure <a class="elsevierStyleCrossRef" href="#bib0455">&#91;3&#93;</a>&#46; Like other normal spinel structures&#44; ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> has cubic symmetry&#44; <span class="elsevierStyleItalic">Fd</span>&#8722;<span class="elsevierStyleItalic">3m</span> space group and 8 formulae per unit cell <a class="elsevierStyleCrossRef" href="#bib0460">&#91;4&#93;</a>&#46; The O<span class="elsevierStyleSup">2&#8722;</span> ions form a closed-packed structure with 64 tet and 32 oct interstices per unit cell&#46; As mentions previously&#44; only <span class="elsevierStyleSup">1</span>&#47;<span class="elsevierStyleInf">8</span> of the tet voids are occupied by Zn<span class="elsevierStyleSup">2&#43;</span>&#44; while the Al<span class="elsevierStyleSup">3&#43;</span> occupies half &#40;&#189;&#41; of the oct voids&#46; Generally&#44; in one FCC unit cell&#44; the effectual number of ions occupying the lattice point is 4 <a class="elsevierStyleCrossRef" href="#bib0465">&#91;5&#93;</a>&#46; Concurrently&#44; the effectual number of ions in the oct and tet voids are 4 and 8&#44; respectively&#46; Hence&#44; in ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#44; Zn<span class="elsevierStyleSup">2&#43;</span> ions occupy 8<span class="elsevierStyleHsp" style=""></span>&#215;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">1</span>&#47;<span class="elsevierStyleInf">8</span><span class="elsevierStyleHsp" style=""></span>&#215;<span class="elsevierStyleHsp" style=""></span>8<span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>8 tet sites of T<span class="elsevierStyleInf">d</span> symmetry and Al<span class="elsevierStyleSup">3&#43;</span> ions occupy 8<span class="elsevierStyleHsp" style=""></span>&#215;<span class="elsevierStyleHsp" style=""></span>&#189;<span class="elsevierStyleHsp" style=""></span>&#215;<span class="elsevierStyleHsp" style=""></span>4<span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>16 oct sites of D<span class="elsevierStyleInf">3d</span> symmetry&#59; while O<span class="elsevierStyleSup">2&#8722;</span> ions occupy 8<span class="elsevierStyleHsp" style=""></span>&#215;<span class="elsevierStyleHsp" style=""></span>4<span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>32 sites of C<span class="elsevierStyleInf">3<span class="elsevierStyleItalic">v</span></span> symmetry <a class="elsevierStyleCrossRef" href="#bib0470">&#91;6&#93;</a>&#46; <a class="elsevierStyleCrossRef" href="#fig0005">Fig&#46; 1</a>&#40;a&#41; shows the schematic illustrations of the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> unit cell with only five oct and seven tet sites&#46; <a class="elsevierStyleCrossRef" href="#fig0005">Fig&#46; 1</a>&#40;b&#41; and &#40;c&#41; shows the coordinates of the tet site and the oct site&#44; respectively&#46;</p><elsevierMultimedia ident="fig0005"></elsevierMultimedia><p id="par0015" class="elsevierStylePara elsevierViewall">Transition-metals have edge over rare earth elements from an economic point of view <a class="elsevierStyleCrossRefs" href="#bib0475">&#91;7&#44;8&#93;</a>&#46; They have the capacity to give broadband emission in the visible and infrared regions <a class="elsevierStyleCrossRefs" href="#bib0450">&#91;2&#44;8&#8211;11&#93;</a>&#44; which leads to their aptness in tunable radiation sources in optical devices <a class="elsevierStyleCrossRefs" href="#bib0500">&#91;12&#8211;15&#93;</a>&#46; In particular&#44; Fe<span class="elsevierStyleSup">3&#43;</span> doped matrices are of special importance due to its ability to emit in lower and higher wavelength ends of the visible spectrum when doped into tet and oct sites&#44; respectively <a class="elsevierStyleCrossRefs" href="#bib0450">&#91;2&#44;16&#93;</a>&#46;</p><p id="par0020" class="elsevierStylePara elsevierViewall">Electrical neutrality can be maintained in a solid material through charge balance&#46; Charge imbalance can lead to the formation of charge defects in the host lattice and hence creates non-radiative luminescence centers in the material <a class="elsevierStyleCrossRef" href="#bib0525">&#91;17&#93;</a>&#46; The presence of non-radiative transitions&#44; largely&#44; can reduce the luminescence emission intensity and hence luminescence efficiency of a phosphor <a class="elsevierStyleCrossRef" href="#bib0530">&#91;18&#93;</a>&#46; Different charge compensation models have been used in enhancing the luminescence of phosphors <a class="elsevierStyleCrossRefs" href="#bib0525">&#91;17&#44;19&#8211;21&#93;</a>&#46; The first model involves a divalent ion replaced by a trivalent ion&#46; In this model&#44; the host has to capture one O<span class="elsevierStyleInf">2</span> from the air to balance the charge differently&#46; The second model involves replacement of three divalent ions by two trivalent ions&#44; with the charge balance contributed by the extra vacancy provided by the excess divalent ion&#46; In the third model&#44; two divalent ions are replaced by one trivalent ion and one alkali metal ion &#40;monovalent ion&#41; is used to balance the charge&#46; The relative intensities of the phosphors prepared using the second and third model was found to be twice that of the phosphor prepared using the first <a class="elsevierStyleCrossRef" href="#bib0540">&#91;20&#93;</a>&#46;</p><p id="par0025" class="elsevierStylePara elsevierViewall">In different instances&#44; researchers have reported ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> doped trivalent metal ions &#40;Dy<span class="elsevierStyleSup">3&#43;</span>&#44; Eu<span class="elsevierStyleSup">3&#43;</span>&#44; Td<span class="elsevierStyleSup">3&#43;</span>&#44; Fe<span class="elsevierStyleSup">3&#43;</span>&#44; Fe<span class="elsevierStyleSup">3&#43;</span>&#44; Ce<span class="elsevierStyleSup">3&#43;</span>&#41;&#44; while substituting the trivalent metal ions in the place of Zn<span class="elsevierStyleSup">2&#43;</span>&#44; without considering the consequences of charge imbalance on the luminescence properties <a class="elsevierStyleCrossRefs" href="#bib0445">&#91;1&#44;2&#44;22&#44;23&#93;</a>&#46; Hence&#44; in this report&#44; the luminescent properties of Zn<span class="elsevierStyleInf">&#40;1&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; matrices were studied&#46; In the Zn<span class="elsevierStyleInf">&#40;1&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> system&#44; one Zn<span class="elsevierStyleSup">2&#43;</span> ion was substituted by one Fe<span class="elsevierStyleSup">3&#43;</span> ion&#46; Because of the charge imbalance in this system&#44; the host has to trap ambient O<span class="elsevierStyleInf">2</span> to compensate for charge&#46; In the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> system&#44; one Al<span class="elsevierStyleSup">3&#43;</span> ion was substituted by one Fe<span class="elsevierStyleSup">3&#43;</span> ion ensuring direct charge balance system&#46;</p></span><span id="sec0010" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0030">Experimental</span><span id="sec0015" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0035">Synthesis</span><p id="par0030" class="elsevierStylePara elsevierViewall">ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> doped with different mol&#37; of Fe<span class="elsevierStyleSup">3&#43;</span> were synthesized using the Pechini synthesis method&#46; The starting materials were zinc nitrate hexahydrate &#40;Zn&#40;NO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">2</span>&#183;6H<span class="elsevierStyleInf">2</span>O&#41;&#44; aluminum nitrate nonahydrate &#40;Al&#40;NO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">3</span>&#183;9H<span class="elsevierStyleInf">2</span>O&#41;&#44; iron nitrate nonahydrate &#40;Fe&#40;NO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">3</span>&#183;9H<span class="elsevierStyleInf">2</span>O&#41;&#44; tartaric acid &#40;C<span class="elsevierStyleInf">4</span>H<span class="elsevierStyleInf">6</span>O<span class="elsevierStyleInf">6</span>&#41; and nitric acid&#46; For the undoped sample&#44; 3&#46;245 and 8&#46;184<span class="elsevierStyleHsp" style=""></span>g mass of Zn&#40;NO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">2</span>&#183;6H<span class="elsevierStyleInf">2</span>O&#44; and Al&#40;NO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">3</span>&#183;9H<span class="elsevierStyleInf">2</span>O&#44; respectively&#44; were dissolved in 10<span class="elsevierStyleHsp" style=""></span>mL of nitric acid in a glass beaker&#44; and it was labeled solution &#8220;A&#8221;&#46; 6&#46;549<span class="elsevierStyleHsp" style=""></span>g of C<span class="elsevierStyleInf">4</span>H<span class="elsevierStyleInf">6</span>O<span class="elsevierStyleInf">6</span> was dissolved in 40<span class="elsevierStyleHsp" style=""></span>mL of distilled water in a different glass beaker&#44; and it was labeled solution &#8220;B&#8221;&#46; Solutions &#8220;A&#8221; and &#8220;B&#8221; were stirred using different magnetic stirrers on a hot plate set at 150<span class="elsevierStyleHsp" style=""></span>&#176;C for about 20<span class="elsevierStyleHsp" style=""></span>min until transparent solutions were obtained&#46; The two transparent solutions were combined and the mixture was stirred at 150<span class="elsevierStyleHsp" style=""></span>&#176;C temperature for about 2<span class="elsevierStyleHsp" style=""></span>h until the liquid evaporated&#46; Prior to the end of the reaction&#44; an evolution of a brownish fume was observed&#46; Still&#44; inside the glass beaker&#44; the sample was dried at 80<span class="elsevierStyleHsp" style=""></span>&#176;C for 10<span class="elsevierStyleHsp" style=""></span>h to get white powder&#46; After grinding the sample with an agate mortar and a pestle&#44; it was calcined at 600<span class="elsevierStyleHsp" style=""></span>&#176;C for 3<span class="elsevierStyleHsp" style=""></span>h&#46; For the doped samples&#44; different amount of Fe&#40;NO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">3</span>&#183;9H<span class="elsevierStyleInf">2</span>O &#40;0&#46;0008&#44; 0&#46;0022&#44; 0&#46;0044&#44; 0&#46;0071<span class="elsevierStyleHsp" style=""></span>g&#41; were added to substitute Al&#40;NO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">3</span>&#183;9H<span class="elsevierStyleInf">2</span>O and create matrices of the form ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41;&#46; A matrix of the form Zn<span class="elsevierStyleInf">&#40;1&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05&#41; was also created by substituting Zn&#40;NO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">2</span>&#183;6H<span class="elsevierStyleInf">2</span>O with 0&#46;0022<span class="elsevierStyleHsp" style=""></span>g of Fe&#40;NO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">3</span>&#183;9H<span class="elsevierStyleInf">2</span>O&#44; the aforementioned procedure was repeated&#46;</p></span><span id="sec0020" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0040">Characterization</span><p id="par0035" class="elsevierStylePara elsevierViewall">A Bruker D8 Advanced X-ray diffractometer &#40;XRD&#41; using monochromatic Cu K&#945; &#40;<span class="elsevierStyleItalic">&#955;</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>1&#46;5406<span class="elsevierStyleHsp" style=""></span>&#8491;&#41; X-ray as radiation source was used to characterize the structure of the materials&#46; The morphologies and the elemental analysis of the powders were studied using a JEOL JSM-7800F field emission scanning electron microscope &#40;FE-SEM&#41; fitted with Oxford X-Max<span class="elsevierStyleSup">N</span> 80 energy-dispersive X-ray spectrometer &#40;EDS&#41;&#46; A PHI 5000 Versaprobe-scanning ESCA microprobe X-ray photoelectron spectroscopy &#40;XPS&#41; was used to obtain the chemical and electronic state data of the samples&#46; A PerkinElmer Lambda 950 UV-Vis spectrometer was used to record the ultraviolet&#8211;visible &#40;UV&#8211;vis&#41; diffuse reflectance data&#46; An FLS980 fluorescence spectrometer-&#40;Edinburgh Instruments&#41; fitted with a 450<span class="elsevierStyleHsp" style=""></span>W Xenon lamp as a source of steady-state excitation was used to collect the PL data&#46;</p></span></span><span id="sec0025" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0045">Results and discussion</span><p id="par0040" class="elsevierStylePara elsevierViewall"><a class="elsevierStyleCrossRef" href="#fig0010">Fig&#46; 2</a>&#40;a&#41; shows the XRD patterns of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; compared to the standard phase of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#44; referenced in JCPDS file no&#46; 82-1043&#46; All the samples show identical patterns as the standard data of spinel ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#44; indicating that they crystallized in a single-phase cubic symmetry and <span class="elsevierStyleItalic">Fd3m</span> space group of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#46; <a class="elsevierStyleCrossRef" href="#fig0010">Fig&#46; 2</a>&#40;b&#41; shows the XRD pattern in the diffraction angle range of 36&#46;6&#8211;37&#46;6 &#40;2<span class="elsevierStyleItalic">&#952;</span>&#41;&#44; depicting the &#40;3<span class="elsevierStyleHsp" style=""></span>1<span class="elsevierStyleHsp" style=""></span>1&#41; diffraction plane&#46; It is seen from <a class="elsevierStyleCrossRef" href="#fig0010">Fig&#46; 2</a>&#40;b&#41; that the &#40;3<span class="elsevierStyleHsp" style=""></span>1<span class="elsevierStyleHsp" style=""></span>1&#41; peak shifted to the lower diffraction angle relative to the undoped sample with increasing Fe<span class="elsevierStyleSup">3&#43;</span><a class="elsevierStyleCrossRefs" href="#bib0560">&#91;24&#44;25&#93;</a>&#46; The shift may be due to distortions in the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> host lattices since the dopant &#40;Fe<span class="elsevierStyleSup">3&#43;</span>&#41; have larger ionic radius than Al<span class="elsevierStyleSup">3&#43;</span> &#40;see <a class="elsevierStyleCrossRef" href="#tbl0005">Table 1</a>&#41; <a class="elsevierStyleCrossRef" href="#bib0570">&#91;26&#93;</a>&#46;</p><elsevierMultimedia ident="fig0010"></elsevierMultimedia><elsevierMultimedia ident="tbl0005"></elsevierMultimedia><p id="par0045" class="elsevierStylePara elsevierViewall">The average crystallite size &#40;<span class="elsevierStyleItalic">L</span>&#41; of the phosphors is related to its lattice strain &#40;<span class="elsevierStyleItalic">&#603;</span>&#41; by Williamson&#8211;Hall equation <a class="elsevierStyleCrossRefs" href="#bib0575">&#91;27&#44;28&#93;</a> given by Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0005">&#40;1&#41;</a>&#58;<elsevierMultimedia ident="eq0005"></elsevierMultimedia>where &#946;h&#8201;k&#8201;l is the full width at half maximum &#40;FWHM&#41; of each diffraction peak&#44; <span class="elsevierStyleItalic">&#955;</span> is the wavelength of the X-ray &#40;0&#46;15406<span class="elsevierStyleHsp" style=""></span>nm&#41; used for measurement&#44; <span class="elsevierStyleItalic">&#952;</span> is the Bragg angle and &#954; is a constant related to the crystallite shape&#44; taken as 0&#46;9 for spherical crystals&#46; From a graph of &#946;h&#8201;k&#8201;l&#8201;Cos&#8201;&#952; versus 4&#8201;Sin&#8201;&#952;&#44; the crystallite size and the strain were determined from the <span class="elsevierStyleItalic">y</span>-intercept and the slope of the graph&#44; respectively&#46; The estimated values of the crystallite sizes and the strain for the undoped sample and for the samples doped with different concentration of Fe<span class="elsevierStyleSup">3&#43;</span> are listed in <a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a>&#46; It is evident from <a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a> that the crystallite size and the strain increased with the Fe<span class="elsevierStyleSup">3&#43;</span> concentration&#46;</p><elsevierMultimedia ident="tbl0010"></elsevierMultimedia><p id="par0050" class="elsevierStylePara elsevierViewall">The lattice constant &#40;lattice parameter&#41; defines the physical dimension of a unit cells in a crystal lattice&#46; For a cubic crystal&#44; the lattice parameter &#40;<span class="elsevierStyleItalic">a</span>&#41; &#40;the length of the edges of the unit cells&#41;&#44; the interplanar spacing &#40;<span class="elsevierStyleItalic">d</span>&#41; &#40;the perpendicular distance between successive parallel planes of the atoms in a crystal&#41;&#44; and the Miller indices &#40;<span class="elsevierStyleItalic">h</span><span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleItalic">k</span><span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleItalic">l</span>&#41; &#40;notations for planes in crystal lattices&#41; are related by Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0010">&#40;2&#41;</a><a class="elsevierStyleCrossRef" href="#bib0585">&#91;29&#93;</a>&#58;<elsevierMultimedia ident="eq0010"></elsevierMultimedia></p><p id="par0055" class="elsevierStylePara elsevierViewall">The <span class="elsevierStyleItalic">d</span> is related to the X-ray wavelength &#40;<span class="elsevierStyleItalic">&#955;</span>&#41; and the diffraction angle &#40;<span class="elsevierStyleItalic">&#952;</span>&#41; by Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0010">&#40;2&#41;</a>&#58;<elsevierMultimedia ident="eq0015"></elsevierMultimedia></p><p id="par0060" class="elsevierStylePara elsevierViewall">Hence&#44; the values of &#8216;<span class="elsevierStyleItalic">a</span>&#8217; and &#8216;<span class="elsevierStyleItalic">b</span>&#8217; can be calculated using Eqs&#46; <a class="elsevierStyleCrossRefs" href="#eq0010">&#40;2&#41; and &#40;3&#41;</a> and the value of the &#8216;<span class="elsevierStyleItalic">&#952;</span>&#8217; can be determined from the XRD data&#46; The calculated values of <span class="elsevierStyleItalic">a</span> are listed in <a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a>&#46; In spite of having cubic symmetry&#44; spinels structures cannot be explained entirely by the lattice parameters &#40;<span class="elsevierStyleItalic">a</span>&#41;&#46; An additional dimensionless parameter &#40;oxygen parameter&#44; <span class="elsevierStyleItalic">u</span>&#41; is used to define the slight distortion that occur in the FCC oxygen lattice for a complete description of the spinel lattice points <a class="elsevierStyleCrossRef" href="#bib0590">&#91;30&#93;</a>&#46; For an undistorted oxygen lattice in spinels&#44; <span class="elsevierStyleItalic">u</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;250 if the origin of the unit cell is taken at the center of symmetry&#46; The oxygen parameter&#44; <span class="elsevierStyleItalic">u</span>&#44; the lattice parameter&#44; <span class="elsevierStyleItalic">a</span>&#44; and the cation-anion distance in the tet and oct sites &#40;Rtet and Roct&#44; respectively&#41; are related by Eqs&#46; <a class="elsevierStyleCrossRefs" href="#eq0020">&#40;4&#41; and &#40;5&#41;</a><a class="elsevierStyleCrossRef" href="#bib0595">&#91;31&#93;</a>&#58;<elsevierMultimedia ident="eq0020"></elsevierMultimedia><elsevierMultimedia ident="eq0025"></elsevierMultimedia></p><p id="par0065" class="elsevierStylePara elsevierViewall">Inasmuch as <span class="elsevierStyleItalic">a</span> and <span class="elsevierStyleItalic">u</span> give information about the lattice positions&#44; for an absolute representation of the spinel lattice&#44; the proportion of cations occupying the different sites should be determined&#46; The distribution parameter &#40;<span class="elsevierStyleItalic">y</span>&#41; is the degree of inversion and it defines the fraction of the trivalent ions occupying the tet sites&#46; Hence&#44; it varies from 0 to 1 for totally normal and inverse spinels&#44; respectively&#46; Eqs&#46; <a class="elsevierStyleCrossRefs" href="#eq0020">&#40;4&#41; and &#40;5&#41;</a> are valid for only &#8220;perfect&#8221; normal or inverse spinels&#46; The distribution of cations in the sites of normal spinels such as gahnite&#44; ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#44; is represented by formula &#123;1&#125;&#58;<elsevierMultimedia ident="eq0030"></elsevierMultimedia>with the divalent cations&#44; Zn<span class="elsevierStyleSup">2&#43;</span>&#44; occupying the tet sites &#40;tet&#41; and the trivalent cations&#44; Al<span class="elsevierStyleSup">3&#43;</span>&#44; occupying the oct sites <a class="elsevierStyleCrossRef" href="#bib0590">&#91;30&#93;</a>&#46; Doping ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> with different concentrations Fe<span class="elsevierStyleSup">3&#43;</span> will result in the formation of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> composite&#44; resulting in the creation of some Fe&#8211;O&#8211;Fe bonds in the matrix&#46; This may lead to the formation of some spinel ferrites &#40;ZnFe<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#41;&#44; which have similar structure as ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#44; within the matrix <a class="elsevierStyleCrossRef" href="#bib0600">&#91;32&#93;</a>&#46; Furthermore&#44; some of the Fe<span class="elsevierStyleSup">3&#43;</span> can be reduced to Fe<span class="elsevierStyleSup">2&#43;</span> as confirmed by the XPS result &#40;<a class="elsevierStyleCrossRef" href="#fig0040">Fig&#46; 8</a>&#40;a&#41;&#41; via the equation Fe<span class="elsevierStyleSup">3&#43;</span><span class="elsevierStyleHsp" style=""></span>&#43;<span class="elsevierStyleHsp" style=""></span>e<span class="elsevierStyleSup">&#8722;</span><span class="elsevierStyleHsp" style=""></span>&#8594;<span class="elsevierStyleHsp" style=""></span>Fe<span class="elsevierStyleSup">2&#43;</span><a class="elsevierStyleCrossRefs" href="#bib0605">&#91;33&#44;34&#93;</a>&#44; resulting in the formation of iron oxides&#44; such as Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span> &#40;magnetite&#41; within the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> matrix&#46; The existence of Fe<span class="elsevierStyleSup">2&#43;</span> in the matrices indicates that ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> does not crystallize in a pure normal spinel phase&#44; rather it crystallized as a mixture of normal and inverse spinel&#44; since Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span> crystallizes in an inverse spinel&#46; In inverse spinels&#44; such as magnetite&#44; Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span>&#44; the distribution of the cations in the sites are represented by formula &#123;2&#125;&#58;<elsevierMultimedia ident="eq0035"></elsevierMultimedia></p><p id="par0070" class="elsevierStylePara elsevierViewall">with one-half of the trivalent cations&#44; Fe<span class="elsevierStyleSup">3&#43;</span>&#44; occupying the tet sites&#44; while both the divalent cations&#44; Fe<span class="elsevierStyleSup">2&#43;</span>&#44; and the remaining Fe<span class="elsevierStyleSup">3&#43;</span> share the oct sites <a class="elsevierStyleCrossRef" href="#bib0590">&#91;30&#93;</a>&#46;</p><p id="par0075" class="elsevierStylePara elsevierViewall">Furthermore&#44; a solid solution formed by ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> and Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span> is represented by formula &#123;3&#125;&#44; by combining formula &#123;1&#125; and &#123;2&#125;&#44; bearing in mind that Zn<span class="elsevierStyleSup">2&#43;</span> and Fe<span class="elsevierStyleSup">3&#43;</span> prefer the tet site in ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span>&#44; respectively&#46;<elsevierMultimedia ident="eq0040"></elsevierMultimedia></p><p id="par0080" class="elsevierStylePara elsevierViewall">In formula &#123;3&#125;&#44; we assumed that ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and ZnFe<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> have similar structure &#40;normal spinels&#41;&#44; and hence the combination of the two compounds should not have substantial effect on the spinel type&#46; Formula &#123;3&#125; will form a solid solution with properties lying between normal and inverse spinels&#46; In the case where more than one cation occupies the same site&#44; the bond length is determined by finding the effective bond length &#8211; i&#46;e&#46; the average of the individual cationic bond length <a class="elsevierStyleCrossRef" href="#bib0590">&#91;30&#93;</a>&#46; Therefore&#44; for a cation&#44; <span class="elsevierStyleItalic">i</span> with bond length <span class="elsevierStyleItalic">R</span><span class="elsevierStyleInf"><span class="elsevierStyleItalic">i</span></span> and mole fraction <span class="elsevierStyleItalic">z</span><span class="elsevierStyleInf"><span class="elsevierStyleItalic">i</span></span> on the tet site the effective bond length is defined by Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0045">&#40;6&#41;</a>&#58;<elsevierMultimedia ident="eq0045"></elsevierMultimedia></p><p id="par0085" class="elsevierStylePara elsevierViewall">also&#44; a similar expression is used for Roct&#46; The bond lengths were determined by combining Eqs&#46; <a class="elsevierStyleCrossRefs" href="#eq0020">&#40;4&#41;&#8211;&#40;6&#41;</a>&#44; and substituting the values of <span class="elsevierStyleItalic">u</span> and <span class="elsevierStyleItalic">a</span> for the end members&#44; ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and Re<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span> from <a class="elsevierStyleCrossRef" href="#tbl0015">Table 3</a>&#46; Also keeping in mind that the tet sites are completely occupied by Zn<span class="elsevierStyleSup">2&#43;</span> in ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and by Fe<span class="elsevierStyleSup">3&#43;</span> in Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span>&#46; The resulting values of the bond lengths are listed in <a class="elsevierStyleCrossRef" href="#tbl0015">Table 3</a>&#46;</p><elsevierMultimedia ident="tbl0015"></elsevierMultimedia><p id="par0090" class="elsevierStylePara elsevierViewall">It is seen from formula &#123;3&#125; that Zn<span class="elsevierStyleSup">2&#43;</span> and Al<span class="elsevierStyleSup">3&#43;</span> only occupy the tet and oct sites&#44; respectively&#46; Hence&#44; the change of the crystal structure with the composition of Fe will depend on the distribution of the Fe<span class="elsevierStyleSup">3&#43;</span> and Fe<span class="elsevierStyleSup">2&#43;</span> cations in the available tet and oct sites&#44; respectively&#46; In additions&#44; <span class="elsevierStyleItalic">a</span> varies linearly with the dopant concentration &#40;<span class="elsevierStyleItalic">x</span>&#41; &#40;see <a class="elsevierStyleCrossRef" href="#fig0015">Fig&#46; 3</a>&#41;&#44; hence&#44; the distribution of Fe<span class="elsevierStyleSup">2&#43;</span> and Fe<span class="elsevierStyleSup">3&#43;</span> varies linearly within the crystal&#46; For <span class="elsevierStyleItalic">y</span> fraction of Fe<span class="elsevierStyleSup">3&#43;</span> and Fe<span class="elsevierStyleSup">2&#43;</span> occupying the tet and oct sites&#44; respectively&#44; Rtet and Roct are given by Eqs&#46; <a class="elsevierStyleCrossRefs" href="#eq0050">&#40;7&#41; and &#40;8&#41;</a>&#44; respectively&#44; for the sample with <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#46;<elsevierMultimedia ident="eq0050"></elsevierMultimedia><elsevierMultimedia ident="eq0055"></elsevierMultimedia></p><elsevierMultimedia ident="fig0015"></elsevierMultimedia><p id="par0095" class="elsevierStylePara elsevierViewall">By equating Eqs&#46; <a class="elsevierStyleCrossRefs" href="#eq0020">&#40;4&#41; and &#40;5&#41;</a> to Eqs&#46; <a class="elsevierStyleCrossRefs" href="#eq0050">&#40;7&#41; and &#40;8&#41;</a>&#44; respectively&#44; and substituting the values of the bond lengths <span class="elsevierStyleItalic">R</span> and the lattice parameters <span class="elsevierStyleItalic">a</span>&#44; the values of <span class="elsevierStyleItalic">y</span> and <span class="elsevierStyleItalic">u</span> can be determined&#46; Following the same procedure&#44; the value of <span class="elsevierStyleItalic">y</span> and <span class="elsevierStyleItalic">u</span> is determined for the rest of the samples&#44; and the results are presented in <a class="elsevierStyleCrossRef" href="#tbl0020">Table 4</a>&#46;</p><elsevierMultimedia ident="tbl0020"></elsevierMultimedia><p id="par0100" class="elsevierStylePara elsevierViewall">The FE-SEM images of the undoped and 0&#46;08<span class="elsevierStyleHsp" style=""></span>mol&#37; Fe<span class="elsevierStyleSup">3&#43;</span> doped ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> are shown in <a class="elsevierStyleCrossRef" href="#fig0020">Fig&#46; 4</a>&#40;a&#41; and &#40;b&#41;&#44; respectively&#46; Fe<span class="elsevierStyleSup">3&#43;</span> doping showed no significant effect on the morphologies of the phosphors&#46; Both images show agglomerated spherical grains with what appear to be distinctive grain boundaries and varying grain sizes&#46; The average diameters of the particles were taken randomly using the line tool in the ImageJ software&#44; version IJ 1&#46;46r <a class="elsevierStyleCrossRef" href="#bib0625">&#91;37&#93;</a>&#46; The size distribution curves were obtained from the FE-SEM images&#44; with estimated mean grain sizes of 112<span class="elsevierStyleHsp" style=""></span>&#177;<span class="elsevierStyleHsp" style=""></span>5 and 118<span class="elsevierStyleHsp" style=""></span>&#177;<span class="elsevierStyleHsp" style=""></span>6<span class="elsevierStyleHsp" style=""></span>nm for the undoped and 0&#46;08<span class="elsevierStyleHsp" style=""></span>mol&#37; Fe<span class="elsevierStyleSup">3&#43;</span> doped ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> as shown in the insets of <a class="elsevierStyleCrossRef" href="#fig0020">Fig&#46; 4</a>&#40;a&#41; and &#40;b&#41;&#44; respectively&#46; The estimated grain sizes for the samples doped with other mol&#37; of Fe<span class="elsevierStyleSup">3&#43;</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; were 115&#44; 117&#44; 124 and 128<span class="elsevierStyleHsp" style=""></span>nm&#44; respectively&#46; Compared to the crystallite size obtained from the XRD data&#44; the grain size is much bigger&#46; Wang&#44; Li&#44; and Tamrakar et al&#46; have reported similar result <a class="elsevierStyleCrossRefs" href="#bib0630">&#91;38&#8211;40&#93;</a>&#46; The grain size and the crystallite size of the particles are different owing to the formation of polycrystalline aggregates <a class="elsevierStyleCrossRef" href="#bib0645">&#91;41&#93;</a>&#44; which appears as one particle in SEM&#44; especially in amorphous materials <a class="elsevierStyleCrossRef" href="#bib0635">&#91;39&#93;</a>&#46;</p><elsevierMultimedia ident="fig0020"></elsevierMultimedia><p id="par0105" class="elsevierStylePara elsevierViewall">The EDS was used for the semiquantitative and the elemental composition analysis of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&#44; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#8211;0&#46;08 phosphors and the spectra for <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0 and 0&#46;08 are shown in <a class="elsevierStyleCrossRef" href="#fig0025">Fig&#46; 5</a>&#40;a&#41; and &#40;b&#41;&#44; respectively&#46; The elements &#40;Zn&#44; Al and O&#41; expected in the compounds are present in the EDS spectra of the all samples&#46; In the doped samples&#44; 0&#46;1<span class="elsevierStyleHsp" style=""></span>at&#46;&#37; of Fe was observed in the samples with high concentration of Fe &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05 and 0&#46;08&#41;&#46; The same amount of Fe was measured in the EDS spectra of the samples&#44; even though they contain different concentration of Fe&#46; This could be due to the detection limit of the technique &#8764; 0&#46;1&#37; <a class="elsevierStyleCrossRef" href="#bib0650">&#91;42&#93;</a>&#46; This imply that measured values of 0&#46;05 and 0&#46;14&#37; should be approximated to 0&#46;1&#37;&#46; The presence of carbon &#40;C&#41; in the EDS spectra could be from environmental hydrocarbon and&#47;or carbon tape on which the samples were mounted&#46; The insets of <a class="elsevierStyleCrossRef" href="#fig0025">Fig&#46; 5</a>&#40;a&#41; and &#40;b&#41; are the measured elemental concentration at&#46;&#37; of all the elements present in the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&#44; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0 and 0&#46;08 samples&#44; and <a class="elsevierStyleCrossRef" href="#tbl0025">Table 5</a> presents the elemental concentration at&#46;&#37; present in the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05 and 0&#46;08&#41; phosphors&#46;</p><elsevierMultimedia ident="fig0025"></elsevierMultimedia><elsevierMultimedia ident="tbl0025"></elsevierMultimedia><p id="par0110" class="elsevierStylePara elsevierViewall">XPS is an in situ technique where a specimen is irradiated with X-rays leading to ionization&#44; and ejection of photoelectrons from the core-shell and the kinetic energies distribution are measured using electron energy analyzer and a photoelectron spectrum can thus be recorded <a class="elsevierStyleCrossRef" href="#bib0655">&#91;43&#93;</a>&#46; XPS was used to determine the electronic and chemical bonding state from the surface of the samples&#46; The XPS spectra were fitted using the PHI MULTIPAK software&#44; version 8&#46;2C <a class="elsevierStyleCrossRef" href="#bib0660">&#91;44&#93;</a>&#46;</p><p id="par0115" class="elsevierStylePara elsevierViewall"><a class="elsevierStyleCrossRef" href="#fig0030">Fig&#46; 6</a>&#40;a&#41;&#8211;&#40;d&#41; shows&#44; respectively&#44; the fitted high-resolution O 1s XPS spectra of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> for <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;05 and 0&#46;08&#46; The spectra show two peaks for the undoped ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> sample &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; <a class="elsevierStyleCrossRef" href="#fig0030">Fig&#46; 6</a>&#40;a&#41;&#41;&#44; but exhibits three peaks for the Fe<span class="elsevierStyleSup">3&#43;</span> doped samples &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#44; 0&#46;05 and 0&#46;08&#44; <a class="elsevierStyleCrossRef" href="#fig0030">Fig&#46; 6</a>&#40;b&#8211;d&#41;&#41;&#46; The two components centered at 531&#46;3 and 533&#46;0<span class="elsevierStyleHsp" style=""></span>eV in <a class="elsevierStyleCrossRef" href="#fig0030">Fig&#46; 6</a>&#40;a&#41; are ascribed to the metal&#8211;oxygen &#40;M&#8211;O&#41; bonds <a class="elsevierStyleCrossRef" href="#bib0665">&#91;45&#93;</a> and O&#8211;H bonds from water molecules absorbed from the environmental moisture&#44; respectively <a class="elsevierStyleCrossRefs" href="#bib0670">&#91;46&#44;47&#93;</a>&#46; The additional peak centered at 534&#46;1<span class="elsevierStyleHsp" style=""></span>eV for <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01 and 534&#46;0<span class="elsevierStyleHsp" style=""></span>eV for <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05 and 0&#46;08 is ascribed to the Fe&#8211;OH bonds <a class="elsevierStyleCrossRef" href="#bib0680">&#91;48&#93;</a>&#46; This indicates that Fe ions were incorporated successfully into the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> host&#46; The peaks belonging to M&#8211;O and O&#8211;H bonds in <a class="elsevierStyleCrossRef" href="#fig0030">Fig&#46; 6</a>&#40;a&#41;&#8211;&#40;d&#41; shifted slightly to lower binding energy after Fe<span class="elsevierStyleSup">3&#43;</span> doping&#46;</p><elsevierMultimedia ident="fig0030"></elsevierMultimedia><p id="par0120" class="elsevierStylePara elsevierViewall">The Al 2p high-resolution XPS spectra for ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;05 and 0&#46;08&#41;&#44; are shown&#44; respectively&#44; in <a class="elsevierStyleCrossRef" href="#fig0035">Fig&#46; 7</a>&#40;a&#41;&#8211;&#40;d&#41;&#46; The two peaks centered at 74&#46;2 and 75&#46;1<span class="elsevierStyleHsp" style=""></span>eV in <a class="elsevierStyleCrossRef" href="#fig0035">Fig&#46; 7</a>&#40;a&#41; were ascribed to Al ions occupying the tet and oct sites by Tshabalala et al&#46; <a class="elsevierStyleCrossRef" href="#bib0685">&#91;49&#93;</a>&#44; in comparison with a report on Y<span class="elsevierStyleInf">3</span>Al<span class="elsevierStyleInf">5</span>O<span class="elsevierStyleInf">12</span> &#40;YAG&#41; by Pawlak et al&#46; <a class="elsevierStyleCrossRef" href="#bib0690">&#91;50&#93;</a>&#46; However&#44; YAG has an entirely different structure from ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#46; In the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> system&#44; the tet sites is occupied by only Zn<span class="elsevierStyleSup">2&#43;</span> ions and the oct sites is occupied by only Al<span class="elsevierStyleSup">3&#43;</span> ions <a class="elsevierStyleCrossRef" href="#bib0590">&#91;30&#93;</a> as shown in <a class="elsevierStyleCrossRef" href="#fig0005">Fig&#46; 1</a> and by formula &#123;1&#125;&#44; while in YAG&#44; Al<span class="elsevierStyleSup">3&#43;</span> ions can occupy both tet and oct sites <a class="elsevierStyleCrossRef" href="#bib0690">&#91;50&#93;</a>&#46; Furthermore&#44; similar XPS peaks have been observed in doped Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span> samples and where assigned to M&#8211;Al&#8211;O or M&#8211;Al &#40;M<span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>metal ion&#41; <a class="elsevierStyleCrossRefs" href="#bib0695">&#91;51&#8211;55&#93;</a>&#46; For instance&#44; in the La<span class="elsevierStyleInf">1&#8722;<span class="elsevierStyleItalic">x</span></span>Al<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span>O<span class="elsevierStyleInf">3</span> system&#44; it was assigned to La&#8211;Al&#8211;O by Fei et al&#46; <a class="elsevierStyleCrossRef" href="#bib0695">&#91;51&#93;</a>&#44; while in the Ru&#47;La&#40;<span class="elsevierStyleItalic">x</span>&#41;&#8211;Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span> system&#44; it was assigned to Al&#8211;La by Chung et al&#46; <a class="elsevierStyleCrossRef" href="#bib0700">&#91;52&#93;</a>&#46; Another point that is worth noting is that the peak around 76&#46;0<span class="elsevierStyleHsp" style=""></span>eV in <a class="elsevierStyleCrossRef" href="#fig0035">Fig&#46; 7</a>&#40;b&#41;&#8211;&#40;d&#41; &#40;assigned to tet Al by Tshabalala et al&#46; <a class="elsevierStyleCrossRef" href="#bib0685">&#91;49&#93;</a>&#41; appears at higher binding energy compare to the other peak &#40;around 74<span class="elsevierStyleHsp" style=""></span>eV&#41; which they assigned to oct Al&#46; However&#44; it is expected that the higher the number of oxygen coordinating a metal ion&#44; the higher the binding energy since the binding energy increase with electronegativity <a class="elsevierStyleCrossRef" href="#bib0720">&#91;56&#93;</a>&#46; Therefore&#44; we believe that the photoelectron peaks at the lower binding energy &#40;74&#46;2<span class="elsevierStyleHsp" style=""></span>eV&#41; and higher binding energy &#40;75&#46;1<span class="elsevierStyleHsp" style=""></span>eV&#41; in <a class="elsevierStyleCrossRef" href="#fig0035">Fig&#46; 7</a>&#40;a&#41; are due to the Al&#8211;O in AlO<span class="elsevierStyleInf">6</span> &#40;Al<span class="elsevierStyleSup">3&#43;</span> ions in the oct sites&#41; <a class="elsevierStyleCrossRef" href="#bib0685">&#91;49&#93;</a> and AL&#8211;OH <a class="elsevierStyleCrossRef" href="#bib0725">&#91;57&#93;</a> in AlO<span class="elsevierStyleInf">6</span>&#44; respectively&#46; For the Fe<span class="elsevierStyleSup">3&#43;</span> doped samples&#44; an additional photoelectron peak appeared at the higher binding energy centered at 76&#46;0<span class="elsevierStyleHsp" style=""></span>eV for the sample doped with 0&#46;01<span class="elsevierStyleHsp" style=""></span>mol&#37; of Fe<span class="elsevierStyleSup">3&#43;</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#41; and at 76&#46;1<span class="elsevierStyleHsp" style=""></span>eV for &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05 and 0&#46;08&#41; as shown in <a class="elsevierStyleCrossRef" href="#fig0035">Fig&#46; 7</a>&#40;b&#41;&#8211;&#40;d&#41;&#46; It is also evident from <a class="elsevierStyleCrossRef" href="#fig0035">Fig&#46; 7</a>&#40;b&#41;&#8211;&#40;d&#41; that the peaks from Al&#8211;O and AL&#8211;OH shifted to lower binding energies at higher Fe<span class="elsevierStyleSup">3&#43;</span> doping concentration&#46; The additional peaks observed at 76&#46;0<span class="elsevierStyleHsp" style=""></span>eV in <a class="elsevierStyleCrossRef" href="#fig0035">Fig&#46; 7</a>&#40;b&#41; and at 76&#46;1<span class="elsevierStyleHsp" style=""></span>eV in <a class="elsevierStyleCrossRef" href="#fig0035">Fig&#46; 7</a>&#40;c&#41; and &#40;d&#41;&#44; are assigned to the Al&#8211;O&#8211;Fe at the oct sites&#44; in the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> system <a class="elsevierStyleCrossRefs" href="#bib0695">&#91;51&#44;52&#93;</a>&#46; It is interesting to observe that the intensity of the photoelectron peaks from the Al&#8211;O&#8211;Fe increased with increasing Fe<span class="elsevierStyleSup">3&#43;</span> concentration&#44; but the intensities of the photoelectron peaks from Al&#8211;O decreased&#46; This shows that more Al&#8211;O&#8211;Fe are created in the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> system with increasing Fe<span class="elsevierStyleSup">3&#43;</span> concentration&#46; The peaks assigned to Al&#8211;O&#8211;Fe in <a class="elsevierStyleCrossRef" href="#fig0035">Fig&#46; 7</a>&#40;b&#41;&#8211;&#40;d&#41; appears at higher binding energy with respect to the other peaks assigned to Al&#8211;O and AL&#8211;OH&#44; because Fe &#40;1&#46;83&#41; have higher electronegativity than Al &#40;1&#46;61&#41; <a class="elsevierStyleCrossRef" href="#bib0730">&#91;58&#93;</a>&#46;</p><elsevierMultimedia ident="fig0035"></elsevierMultimedia><p id="par0125" class="elsevierStylePara elsevierViewall">The deconvoluted Zn 2p XPS spectra for the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;05 and 0&#46;08&#41; are shown in <a class="elsevierStyleCrossRef" href="#fig0040">Fig&#46; 8</a>&#40;a&#41;&#8211;&#40;d&#41;&#44; respectively&#46; For the undoped ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> shown in <a class="elsevierStyleCrossRef" href="#fig0040">Fig&#46; 8</a>&#40;a&#41;&#44; a double peak from the Zn 2p core-level were observed at 1021&#46;9 and 1045&#46;0<span class="elsevierStyleHsp" style=""></span>eV and are assigned to the Zn 2p<span class="elsevierStyleInf">3&#47;2</span> and Zn 2p<span class="elsevierStyleInf">1&#47;2</span><a class="elsevierStyleCrossRef" href="#bib0735">&#91;59&#93;</a> from the Zn occupying the tet site &#40;ZnO<span class="elsevierStyleInf">4</span>&#41; in ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#44; respectively&#46; For the Fe<span class="elsevierStyleSup">3&#43;</span> doped samples &#40;<a class="elsevierStyleCrossRef" href="#fig0040">Fig&#46; 8</a>&#40;b&#8211;d&#41;&#41;&#44; a new photoelectron peak was observed at the higher binding energy with respect to the Zn 2p<span class="elsevierStyleInf">3&#47;2</span> and Zn 2p<span class="elsevierStyleInf">1&#47;2</span> peaks which shifted to high binding energy values with increasing Fe<span class="elsevierStyleSup">3&#43;</span> ions concentration&#46; These peaks are centered at 1022&#46;7 and 1045&#46;9<span class="elsevierStyleHsp" style=""></span>eV&#44; 1023&#46;4 and 1046&#46;5<span class="elsevierStyleHsp" style=""></span>eV&#44; 1024&#46;4 and 1047&#46;6<span class="elsevierStyleHsp" style=""></span>eV for ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#44; 0&#46;05 and 0&#46;08&#41;&#44; respectively&#44; as shown in <a class="elsevierStyleCrossRef" href="#fig0040">Fig&#46; 8</a>&#40;b&#41;&#8211;&#40;d&#41; and they are assigned to Zn&#8211;O&#8211;Fe in the tet sites&#46; Yngman et al&#46; have reported a similar result in Zn doped GaAs <a class="elsevierStyleCrossRef" href="#bib0740">&#91;60&#93;</a>&#44; Li et al&#46; in Cu doped ZnS <a class="elsevierStyleCrossRef" href="#bib0745">&#91;61&#93;</a> and Beltr&#225;n et al&#46; in carbon doped ZnO <a class="elsevierStyleCrossRef" href="#bib0750">&#91;62&#93;</a>&#46;</p><elsevierMultimedia ident="fig0040"></elsevierMultimedia><p id="par0130" class="elsevierStylePara elsevierViewall">The peaks assigned to Zn&#8211;O&#8211;Fe in <a class="elsevierStyleCrossRef" href="#fig0040">Fig&#46; 8</a>&#40;b&#41;&#8211;&#40;d&#41; appeared at higher binding energy values with respect to the peaks assigned to Zn in ZnO<span class="elsevierStyleInf">4</span>&#44; because Fe &#40;1&#46;83&#41; have higher electronegativity than Zn &#40;1&#46;65&#41; <a class="elsevierStyleCrossRef" href="#bib0730">&#91;58&#93;</a>&#46; However&#44; Zhang et al&#46; <a class="elsevierStyleCrossRefs" href="#bib0735">&#91;59&#44;63&#93;</a> attributed the photoelectron peaks at the lower binding energies in Zn 2p<span class="elsevierStyleInf">3&#47;2</span> and Zn 2p<span class="elsevierStyleInf">1&#47;2</span> to Zn<span class="elsevierStyleSup">2&#43;</span> ions occupying tet sites and the photoelectron peaks at higher binding energies in Zn 2p<span class="elsevierStyleInf">3&#47;2</span> and Zn 2p<span class="elsevierStyleInf">1&#47;2</span> to Zn<span class="elsevierStyleSup">2&#43;</span> occupying the oct sites in ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58;Cr<span class="elsevierStyleSup">3&#43;</span> system&#46; However&#44; they did not show the XPS spectrum for the undoped ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#46; In <a class="elsevierStyleCrossRef" href="#fig0040">Fig&#46; 8</a>&#40;a&#41;&#44; the XPS spectrum for the undoped ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> did not show any sign of the two photoelectron peaks sitting at the higher binding energies with respect to the Zn 2p<span class="elsevierStyleInf">3&#47;2</span> and Zn 2p<span class="elsevierStyleInf">1&#47;2</span> peaks&#46; This suggests that the two peaks sitting at higher binding energies to Zn 2p<span class="elsevierStyleInf">3&#47;2</span> and Zn 2p<span class="elsevierStyleInf">1&#47;2</span> peaks in <a class="elsevierStyleCrossRef" href="#fig0040">Fig&#46; 8</a>&#40;a&#41; are associated with Fe ions&#46; The intensities of the photoelectron peaks from the Zn&#8211;O&#8211;Fe in <a class="elsevierStyleCrossRef" href="#fig0040">Fig&#46; 8</a>&#40;b&#41;&#8211;&#40;d&#41; increased as the Fe<span class="elsevierStyleSup">3&#43;</span> ions concentration increased in ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> system&#46; However&#44; unlike the Al 2p peaks&#44; there was no significant change in the Zn 2p peaks intensities&#46; The formation of Zn&#8211;O&#8211;Fe and Al&#8211;O&#8211;Fe bonds in the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58; Fe<span class="elsevierStyleSup">3&#43;</span> matrices suggest the possibility of existence of tet and oct Fe in these matrices&#46;</p><p id="par0135" class="elsevierStylePara elsevierViewall">The Fe XPS peaks could not be detected in the samples doped with concentration of up to 0&#46;08<span class="elsevierStyleHsp" style=""></span>mol&#37;&#44; hence we prepared another sample doped with 4<span class="elsevierStyleHsp" style=""></span>mol&#37; of Fe<span class="elsevierStyleSup">3&#43;</span>&#46; <a class="elsevierStyleCrossRef" href="#fig0045">Fig&#46; 9</a>&#40;a&#41; shows the deconvoluted XPS spectrum for Fe 2p peak&#46; The spectrum consists of the shake-up peaks &#40;satellite peaks&#41; and the Fe 2p<span class="elsevierStyleInf">3&#47;2</span> and Fe 2p<span class="elsevierStyleInf">1&#47;2</span> components&#46; Each component of the Fe 2p peak consist of two Fe ion peaks signifying the different oxidation states of Fe ion &#40;Fe<span class="elsevierStyleSup">2&#43;</span> and Fe<span class="elsevierStyleSup">3&#43;</span>&#41;&#46; The shape-up peaks were located relatively at higher binding energies of 713&#46;0<span class="elsevierStyleHsp" style=""></span>eV and 725&#46;4<span class="elsevierStyleHsp" style=""></span>eV with respect to the 2p<span class="elsevierStyleInf">3&#47;2</span> and 2p<span class="elsevierStyleInf">1&#47;2</span> components&#44; respectively <a class="elsevierStyleCrossRefs" href="#bib0760">&#91;64&#44;65&#93;</a>&#46; The photoelectron peaks at the lower binding energies &#40;704&#46;6 and 717&#46;6<span class="elsevierStyleHsp" style=""></span>eV&#41; in the Fe 2p<span class="elsevierStyleInf">3&#47;2</span> and 2p<span class="elsevierStyleInf">1&#47;2</span> components were assigned to Fe<span class="elsevierStyleSup">2&#43;</span>&#44; while the two peaks at the higher binding energies &#40;706&#46;8 and 720&#46;7<span class="elsevierStyleHsp" style=""></span>eV&#41; in the Fe 2p<span class="elsevierStyleInf">3&#47;2</span> and 2p<span class="elsevierStyleInf">1&#47;2</span> components were assigned to Fe<span class="elsevierStyleSup">3&#43;</span><a class="elsevierStyleCrossRefs" href="#bib0760">&#91;64&#8211;66&#93;</a>&#46; With the presence of Fe<span class="elsevierStyleSup">2&#43;</span> in the crystal&#44; <a class="elsevierStyleCrossRef" href="#fig0045">Fig&#46; 9</a>b&#40;i&#8211;iii&#41; shows the possible structural makeup of the samples&#46; The structure is made up of a mixture of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> with tet Zn<span class="elsevierStyleSup">2&#43;</span> and oct Al<span class="elsevierStyleSup">3&#43;</span> &#40;<a class="elsevierStyleCrossRef" href="#fig0045">Fig&#46; 9</a>b&#40;i&#41;&#41;&#44; ZnFe<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> with tet Zn<span class="elsevierStyleSup">2&#43;</span> and oct Fe<span class="elsevierStyleSup">3&#43;</span> &#40;<a class="elsevierStyleCrossRef" href="#fig0045">Fig&#46; 9</a>b&#40;ii&#41;&#41;&#44; and Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span> with tet Fe<span class="elsevierStyleSup">3&#43;</span> and oct Fe<span class="elsevierStyleSup">2&#43;</span> or Fe<span class="elsevierStyleSup">3&#43;</span> &#40;<a class="elsevierStyleCrossRef" href="#fig0045">Fig&#46; 9</a>b&#40;ii&#41;&#41;&#46;</p><elsevierMultimedia ident="fig0045"></elsevierMultimedia><p id="par0140" class="elsevierStylePara elsevierViewall">The UV&#8211;vis spectrometer was used to measure the diffuse reflectance of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors in the wavelength range of 250&#8211;800<span class="elsevierStyleHsp" style=""></span>nm and the spectra are shown in <a class="elsevierStyleCrossRef" href="#fig0050">Fig&#46; 10</a>&#46; The diffuse reflectance spectra show the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> band-to-band transition around 305<span class="elsevierStyleHsp" style=""></span>nm&#46;</p><elsevierMultimedia ident="fig0050"></elsevierMultimedia><p id="par0145" class="elsevierStylePara elsevierViewall">The band gaps of the phosphors were determined from the diffuse reflectance data using the derivative method and Kubelka&#8211;Munk function&#46; In the derivative method&#44; the band gap is determined by taking the first derivative&#44; <span class="elsevierStyleItalic">dR</span>&#47;<span class="elsevierStyleItalic">dE</span>&#44; of the diffuse reflectance data and plotting it against the energy <span class="elsevierStyleItalic">E</span> &#40;eV&#41; <a class="elsevierStyleCrossRef" href="#bib0775">&#91;67&#93;</a> &#40;the wavelength was converted to energy using the relation&#44; <span class="elsevierStyleItalic">E</span> &#40;eV&#41;<span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>1240&#47;<span class="elsevierStyleItalic">&#955;</span> &#40;nm&#41;&#41;&#46; In general&#44; the absorption coefficient of a material is related to the band gap by<elsevierMultimedia ident="eq0060"></elsevierMultimedia>where <span class="elsevierStyleItalic">h</span> is Planck&#39;s constant&#44; <span class="elsevierStyleItalic">v</span> is the frequency&#44; <span class="elsevierStyleItalic">E</span><span class="elsevierStyleInf">g</span> is the material band gap and <span class="elsevierStyleItalic">n</span> depends on the nature of the transition and can take values of &#189;&#44; 3&#47;2&#44; 2 or 3 for allowed direct&#44; forbidden direct&#44; allowed indirect and forbidden indirect transitions&#44; respectively&#46; <span class="elsevierStyleItalic">A</span> is an energy independent proportionality constant <a class="elsevierStyleCrossRef" href="#bib0780">&#91;68&#93;</a>&#46; Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0060">&#40;9&#41;</a> can be written as&#58;<elsevierMultimedia ident="eq0065"></elsevierMultimedia></p><p id="par0150" class="elsevierStylePara elsevierViewall">For a direct band gap material&#44; the absorption coefficient is a function of energy&#44; &#945;&#40;hv&#41;&#44; hence Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0065">&#40;10&#41;</a> can be expressed as<elsevierMultimedia ident="eq0070"></elsevierMultimedia></p><p id="par0155" class="elsevierStylePara elsevierViewall">Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0070">&#40;11&#41;</a> is true for <span class="elsevierStyleItalic">hv</span><span class="elsevierStyleHsp" style=""></span>&#62;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleItalic">E</span><span class="elsevierStyleInf">g</span> but 0 if <span class="elsevierStyleItalic">hv</span><span class="elsevierStyleHsp" style=""></span>&#60;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleItalic">E</span><span class="elsevierStyleInf">g</span>&#46; Taking the first derivative of Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0070">&#40;11&#41;</a> with respect to <span class="elsevierStyleItalic">hv</span> gives<elsevierMultimedia ident="eq0075"></elsevierMultimedia></p><p id="par0160" class="elsevierStylePara elsevierViewall">Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0075">&#40;12&#41;</a> diverges at a point when <span class="elsevierStyleItalic">hc</span>&#47;<span class="elsevierStyleItalic">E</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleItalic">hc</span>&#47;<span class="elsevierStyleItalic">E</span><span class="elsevierStyleInf">g</span>&#44; and this correspond to the band gap of a direct band gap material&#46; At this point Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0075">&#40;12&#41;</a> is reduce to<elsevierMultimedia ident="eq0080"></elsevierMultimedia></p><p id="par0165" class="elsevierStylePara elsevierViewall">For a direct band gap material&#44; Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0080">&#40;13&#41;</a> show a distinct sharp peak&#44; usually taken as the band gap of the material <a class="elsevierStyleCrossRef" href="#bib0775">&#91;67&#93;</a>&#46; <a class="elsevierStyleCrossRef" href="#fig0055">Fig&#46; 11</a> shows the plots of <span class="elsevierStyleItalic">dR</span>&#47;<span class="elsevierStyleItalic">dE</span> versus <span class="elsevierStyleItalic">E</span> &#40;eV&#41; for the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors&#46; It is evident from <a class="elsevierStyleCrossRef" href="#fig0055">Fig&#46; 11</a> that the band gap of the undoped ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> is about 4&#46;23<span class="elsevierStyleHsp" style=""></span>eV&#46; This is in agreement with some of the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> band gap reported in the literature <a class="elsevierStyleCrossRefs" href="#bib0785">&#91;69&#44;70&#93;</a>&#46; The band gap decreased slightly to 4&#46;17<span class="elsevierStyleHsp" style=""></span>eV when 0&#46;01<span class="elsevierStyleHsp" style=""></span>mol&#37; of Fe<span class="elsevierStyleSup">3&#43;</span> was doped into the matric&#46; This could be due to the smaller band gap of ZnFe<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span><a class="elsevierStyleCrossRefs" href="#bib0795">&#91;71&#44;72&#93;</a> compare to ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span><a class="elsevierStyleCrossRefs" href="#bib0785">&#91;69&#44;70&#93;</a>&#46; However&#44; no increased was observe in the band gap for a further increase in the concentration of Fe<span class="elsevierStyleSup">3&#43;</span>&#46;</p><elsevierMultimedia ident="fig0055"></elsevierMultimedia><p id="par0170" class="elsevierStylePara elsevierViewall">The Kubelka&#8211;Munk function is based on the direct and indirect proportionality relation between the absorption coefficient &#40;<span class="elsevierStyleItalic">&#945;</span>&#41; of a material and the <span class="elsevierStyleItalic">R</span>&#44; respectively&#46; <span class="elsevierStyleItalic">R</span> is the reflectance of the material&#46; For a semi-infinite medium&#44; Kubelka&#8211;Munk is defined by Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0085">&#40;14&#41;</a>&#58;<elsevierMultimedia ident="eq0085"></elsevierMultimedia>where R&#8734; is the reflectance of the semi-finite medium <a class="elsevierStyleCrossRef" href="#bib0805">&#91;73&#93;</a>&#46; For a finite medium with 100&#37;&#44; Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0085">&#40;14&#41;</a> takes the form of Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0090">&#40;15&#41;</a>&#58;<elsevierMultimedia ident="eq0090"></elsevierMultimedia></p><p id="par0175" class="elsevierStylePara elsevierViewall">Considering that F&#40;R&#8734;&#41; is proportional to the &#945;&#44; and equating Eqs&#46; <a class="elsevierStyleCrossRefs" href="#eq0060">&#40;9&#41; and &#40;15&#41;</a> gives Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0095">&#40;16&#41;</a>&#58;<elsevierMultimedia ident="eq0095"></elsevierMultimedia></p><p id="par0180" class="elsevierStylePara elsevierViewall">From Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0095">&#40;16&#41;</a>&#44; the band gap can be estimated by plotting a graph of &#40;F&#40;R100&#41;hv&#41;2 versus <span class="elsevierStyleItalic">hv</span> and drawing a straight line from the inflection point of the curve to the <span class="elsevierStyleItalic">hv</span>-axis&#46; <a class="elsevierStyleCrossRef" href="#fig0060">Fig&#46; 12</a> shows the &#40;F&#40;R100&#41;hv&#41;2 versus <span class="elsevierStyleItalic">hv</span> plot for the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors&#46; Interestingly&#44; the values of the band gaps are in agreement with those estimated with the derivative method&#44; with 4&#46;20<span class="elsevierStyleHsp" style=""></span>eV for the undoped ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and 4&#46;17<span class="elsevierStyleHsp" style=""></span>eV for all the doped samples&#46;</p><elsevierMultimedia ident="fig0060"></elsevierMultimedia><p id="par0185" class="elsevierStylePara elsevierViewall">The non-increment in the band gap with increasing concentration of Fe<span class="elsevierStyleSup">3&#43;</span> can be explained by Harrison&#39;s tight binding &#40;TB&#41; model <a class="elsevierStyleCrossRef" href="#bib0810">&#91;74&#93;</a>&#44; which proposed that&#58;<ul class="elsevierStyleList" id="lis0005"><li class="elsevierStyleListItem" id="lsti0005"><span class="elsevierStyleLabel">&#40;i&#41;</span><p id="par0190" class="elsevierStylePara elsevierViewall">The top of the valence band of the host does not change significantly for a small concentration of the dopant and the doped matrix can be adequately explained within the virtual-crystal approximation method&#46;</p></li><li class="elsevierStyleListItem" id="lsti0010"><span class="elsevierStyleLabel">&#40;ii&#41;</span><p id="par0195" class="elsevierStylePara elsevierViewall">The position of the energy of the dopant &#40;impurity&#41; is independent of its concentration &#40;even at the smallest possible concentration&#41;&#46; However&#44; at higher concentration&#44; small shifting and broadening of the dopant states may occur &#40;owing to the electrostatic interactions between the dopant atoms and&#47;or the difference in the bond lengths of the host and the dopant within the matrix&#46;</p></li></ul></p><p id="par0200" class="elsevierStylePara elsevierViewall"><a class="elsevierStyleCrossRef" href="#fig0065">Fig&#46; 13</a>&#40;a&#41; and &#40;b&#41; shows the PL excitation and emission spectra of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors normalized with respect to the dopant concentration&#44; respectively&#46; The excitation spectra &#40;<a class="elsevierStyleCrossRef" href="#fig0065">Fig&#46; 13</a>&#40;a&#41;&#41; was obtained when monitoring the emission at 483<span class="elsevierStyleHsp" style=""></span>nm and scanning the spectrum in the wavelength range of 200&#8211;450<span class="elsevierStyleHsp" style=""></span>nm&#46; Within this wavelength range&#44; two broad bands were observed from 200 to 275<span class="elsevierStyleHsp" style=""></span>nm&#44; with a maximum at 235<span class="elsevierStyleHsp" style=""></span>nm&#44; and from 325 to 415<span class="elsevierStyleHsp" style=""></span>nm&#44; with a maximum around 374<span class="elsevierStyleHsp" style=""></span>nm&#46; The peak at 235<span class="elsevierStyleHsp" style=""></span>nm could be due to the band-to-band transition of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#46; The broadband peaking around 374<span class="elsevierStyleHsp" style=""></span>nm could be relate to ZnO band-to-band transition <a class="elsevierStyleCrossRef" href="#bib0815">&#91;75&#93;</a>&#46; Similar transitions were observed from the absorbance and reflectance of the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> samples <a class="elsevierStyleCrossRefs" href="#bib0460">&#91;4&#44;76&#44;77&#93;</a>&#46; Under the 235<span class="elsevierStyleHsp" style=""></span>nm excitation&#44; two broad emission bands could be distinguished&#44; one with a maximum around 483<span class="elsevierStyleHsp" style=""></span>nm and the other around 730<span class="elsevierStyleHsp" style=""></span>nm&#44; as shown in <a class="elsevierStyleCrossRef" href="#fig0065">Fig&#46; 13</a>&#40;b&#41;&#46;</p><elsevierMultimedia ident="fig0065"></elsevierMultimedia><p id="par0205" class="elsevierStylePara elsevierViewall">The inset of <a class="elsevierStyleCrossRef" href="#fig0065">Fig&#46; 13</a>&#40;a&#41; shows how the emission intensities of the 487 and 730<span class="elsevierStyleHsp" style=""></span>nm bands varied with Fe<span class="elsevierStyleSup">3&#43;</span> concentration&#46; It is apparent from the inset of <a class="elsevierStyleCrossRef" href="#fig0065">Fig&#46; 13</a>&#40;a&#41; that the emission intensity of the 487<span class="elsevierStyleHsp" style=""></span>nm band dropped sharply after doping with just 0&#46;01<span class="elsevierStyleHsp" style=""></span>mol&#37; of Fe<span class="elsevierStyleSup">3&#43;</span>&#44; but as the concentration of Fe<span class="elsevierStyleSup">3&#43;</span> increased&#44; the change in the emission intensity became infinitesimal and intermittent&#46; A similar trend in the luminescence intensity has been reported in ZnGa<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span><a class="elsevierStyleCrossRefs" href="#bib0830">&#91;78&#44;79&#93;</a>&#46; However&#44; the 730<span class="elsevierStyleHsp" style=""></span>nm emission band increased with the Fe<span class="elsevierStyleSup">3&#43;</span> doping concentration&#44; attaining maximum at 0&#46;05<span class="elsevierStyleHsp" style=""></span>mol&#37; of Fe<span class="elsevierStyleSup">3&#43;</span> and decreased afterwards&#46; The emission band observed at 487<span class="elsevierStyleHsp" style=""></span>nm in the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#41; is assigned to the defect related intra-band transitions&#44; such as oxygen vacancies and Zn<span class="elsevierStyleSup">2&#43;</span> interstitials in the spinel lattice <a class="elsevierStyleCrossRefs" href="#bib0450">&#91;2&#44;80&#93;</a>&#46; The quenching of the 487<span class="elsevierStyleHsp" style=""></span>nm band on Fe<span class="elsevierStyleSup">3&#43;</span> doping suggests that the introduction of Fe<span class="elsevierStyleSup">3&#43;</span> into the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> system must have decreased the oxygen vacancies and Zn interstitial sites <a class="elsevierStyleCrossRef" href="#bib0825">&#91;77&#93;</a>&#44; with Fe<span class="elsevierStyleSup">3&#43;</span> filling some of the Zn interstitials&#46; This will lead to the creation of some Fe&#8211;O&#8211;Fe bonds in the matrix and hence resulting in the formation of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> composite&#46; Contrary to the 487<span class="elsevierStyleHsp" style=""></span>nm bands&#44; the emission intensities of the bands at 730<span class="elsevierStyleHsp" style=""></span>nm shows distinctive increment with Fe<span class="elsevierStyleSup">3&#43;</span> concentration&#44; with the highest emission intensity obtained from the samples with 0&#46;05<span class="elsevierStyleHsp" style=""></span>mol&#37; of Fe<span class="elsevierStyleSup">3&#43;</span>&#46; Observe the slight blue shift in the emission band maximum from 487 to 470<span class="elsevierStyleHsp" style=""></span>nm for the undoped and 0&#46;08<span class="elsevierStyleHsp" style=""></span>mol Fe<span class="elsevierStyleSup">3&#43;</span> doped sample&#46; This indicates that these bands were not from the same origin&#46; The emission bands at 470 and 730<span class="elsevierStyleHsp" style=""></span>nm in Fe<span class="elsevierStyleSup">3&#43;</span> doped samples are ascribed to Fe ions occupying the tet and oct sites of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> host&#44; respectively&#46; The PL from the tet coordinated Fe ions is attributed to the <span class="elsevierStyleSup">4</span>E<span class="elsevierStyleHsp" style=""></span>&#43;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">4</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">4</span>G&#41;<span class="elsevierStyleHsp" style=""></span>&#8594;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">6</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">6</span>S&#41; transition&#44; while the oct coordinated Fe ions is attributed to the <span class="elsevierStyleSup">4</span>T<span class="elsevierStyleInf">2</span>&#40;<span class="elsevierStyleSup">4</span>G&#41;<span class="elsevierStyleHsp" style=""></span>&#8594;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">6</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">6</span>S&#41; <a class="elsevierStyleCrossRef" href="#bib0845">&#91;81&#93;</a>&#46; As observed from the XPS result &#40;<a class="elsevierStyleCrossRef" href="#fig0045">Fig&#46; 9</a>&#40;a&#41;&#41;&#44; part of the Fe<span class="elsevierStyleSup">3&#43;</span> was reduced to Fe<span class="elsevierStyleSup">2&#43;</span>&#44; hence both the tet and the oct emission could be from a mixture of Fe<span class="elsevierStyleSup">2&#43;</span> and Fe<span class="elsevierStyleSup">3&#43;</span> ions&#46;</p><p id="par0210" class="elsevierStylePara elsevierViewall">The decay curves originating from the 487 and 730<span class="elsevierStyleHsp" style=""></span>nm emission under the 235<span class="elsevierStyleHsp" style=""></span>nm excitation of the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors are shown in <a class="elsevierStyleCrossRef" href="#fig0070">Fig&#46; 14</a>&#40;a&#41; and &#40;b&#41;&#44; respectively&#46; The decay curves were nicely fitted by a triple exponential equation given by Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0100">&#40;17&#41;</a>&#58;<elsevierMultimedia ident="eq0100"></elsevierMultimedia>with <span class="elsevierStyleItalic">I</span> the PL intensity&#44; <span class="elsevierStyleItalic">A</span>&#44; <span class="elsevierStyleItalic">B</span> and <span class="elsevierStyleItalic">C</span> are the fitting parameters&#44; while &#964;1&#44; &#964;2 and &#964;3 are the decay constants of the exponential components <a class="elsevierStyleCrossRef" href="#bib0850">&#91;82&#93;</a>&#46; The average decay time &#964;&#42; can be determined using Eq&#46; <a class="elsevierStyleCrossRef" href="#eq0105">&#40;18&#41;</a>&#58;<elsevierMultimedia ident="eq0105"></elsevierMultimedia></p><elsevierMultimedia ident="fig0070"></elsevierMultimedia><p id="par0215" class="elsevierStylePara elsevierViewall">The calculated average decay times for the 487 and 730<span class="elsevierStyleHsp" style=""></span>nm emission bands under 235<span class="elsevierStyleHsp" style=""></span>nm excitation are shown in <a class="elsevierStyleCrossRef" href="#tbl0030">Table 6</a>&#46; The inset of <a class="elsevierStyleCrossRef" href="#fig0070">Fig&#46; 14</a>&#40;a&#41; shows the plot of the average lifetime of the phosphors versus the Fe<span class="elsevierStyleSup">3&#43;</span> concentration &#40;<span class="elsevierStyleItalic">x</span>&#41; for the 487<span class="elsevierStyleHsp" style=""></span>nm emission under 235<span class="elsevierStyleHsp" style=""></span>nm excitation&#46; The undoped sample &#40;i&#46;e&#46; ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#41; has the longest lifetime&#44; after which there was a decrease in the lifetime upon Fe<span class="elsevierStyleSup">3&#43;</span> doping&#46; The lifetime measured from the 730<span class="elsevierStyleHsp" style=""></span>nm emission when under the 235<span class="elsevierStyleHsp" style=""></span>nm excitation showed similar behavior like the one observed from the 487<span class="elsevierStyleHsp" style=""></span>nm&#44; but in an opposite manner&#46; As seen in the inset of <a class="elsevierStyleCrossRef" href="#fig0070">Fig&#46; 14</a>&#40;b&#41;&#44; the undoped sample has the shortest lifetime&#44; and the lifetime increased upon Fe<span class="elsevierStyleSup">3&#43;</span> doping&#46; The change in the lifetime upon Fe<span class="elsevierStyleSup">3&#43;</span> doping is a demonstration of that the emissions arises from different lattice sites <a class="elsevierStyleCrossRef" href="#bib0855">&#91;83&#93;</a>&#46; This is a further proof of the existence of the tet and oct Fe sites within the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> matrix&#46;</p><elsevierMultimedia ident="tbl0030"></elsevierMultimedia><p id="par0220" class="elsevierStylePara elsevierViewall"><a class="elsevierStyleCrossRef" href="#fig0075">Fig&#46; 15</a>&#40;a&#41; is a schematic energy diagram showing the emission of Fe&#44; zinc interstitials and oxygen vacancies in ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> host&#46; The valence &#40;VB&#41; band is formed by the hybridization of O<span class="elsevierStyleSup">2&#8722;</span> 2p orbitals and Zn<span class="elsevierStyleSup">2&#43;</span> 3d orbitals&#44; while the conduction band &#40;CB&#41; is formed by Al 3s and 2p orbitals <a class="elsevierStyleCrossRefs" href="#bib0460">&#91;4&#44;84&#44;85&#93;</a>&#46; Upon excitation at 235<span class="elsevierStyleHsp" style=""></span>nm UV-light&#44; electrons excited from the VB to the CB are relaxed non-radiatively to the various luminescent centers in the material before giving emissions&#46; Since the combination of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span> gives a solid solution of the form&#44; &#40;Zn8&#8722;x2&#43;Fex3&#43;&#41;tet&#91;Al8&#8722;x3&#43;Fex3&#43;F82&#43;&#93;octO32&#44; with Fe ions in the both sites&#46; The implication of this is that part of the Fe<span class="elsevierStyleSup">3&#43;</span> are reduce to Fe<span class="elsevierStyleSup">2&#43;</span> in both tet and oct sites&#46; Therefore&#44; the Fe emission from the tet and oct comprises Fe<span class="elsevierStyleSup">3&#43;</span> and Fe<span class="elsevierStyleSup">2&#43;</span> emissions&#46; <a class="elsevierStyleCrossRef" href="#fig0075">Fig&#46; 15</a>&#40;b&#41; illustrates further the schematic energy diagram of Fe ions &#40;Fe<span class="elsevierStyleSup">3&#43;</span> and Fe<span class="elsevierStyleSup">2&#43;</span>&#41; on the tet and the oct sites of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> host&#46; The Fe<span class="elsevierStyleSup">2&#43;</span> ions were generated due to the photoionization Fe<span class="elsevierStyleSup">3&#43;</span> that results to the formation of bound-hole state via the equation&#58; Fe<span class="elsevierStyleSup">3&#43;</span><span class="elsevierStyleHsp" style=""></span>&#43;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleItalic">hv</span><span class="elsevierStyleHsp" style=""></span>&#8594;<span class="elsevierStyleHsp" style=""></span>&#91;Fe<span class="elsevierStyleSup">2&#43;</span>&#44; <span class="elsevierStyleItalic">h</span>&#93; <a class="elsevierStyleCrossRef" href="#bib0870">&#91;86&#93;</a>&#46; The tet site is composed of two emission lines at 470 and 576<span class="elsevierStyleHsp" style=""></span>nm assigned to the <span class="elsevierStyleSup">4</span>E<span class="elsevierStyleHsp" style=""></span>&#43;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">4</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">4</span>G&#41;<span class="elsevierStyleHsp" style=""></span>&#8594;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">6</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">6</span>S&#41; and <span class="elsevierStyleSup">4</span>T<span class="elsevierStyleInf">2</span>&#40;<span class="elsevierStyleSup">4</span>G&#41;<span class="elsevierStyleHsp" style=""></span>&#8594;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">6</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">6</span>S&#41; transitions of Fe<span class="elsevierStyleSup">3&#43;</span>&#44; respectively&#44; while the oct site gave an emission line at 730<span class="elsevierStyleHsp" style=""></span>nm &#40;<span class="elsevierStyleSup">4</span>T<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">4</span>G&#41;<span class="elsevierStyleHsp" style=""></span>&#8594;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">6</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">6</span>S&#41;&#41; <a class="elsevierStyleCrossRef" href="#bib0845">&#91;81&#93;</a>&#46; The recombination of the trapped electrons &#40;bound-hole state&#41; in the tet and oct sites has not been for ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">2</span>&#58;Fe<span class="elsevierStyleSup">3&#43;</span>&#46; However&#44; it has been reported around 693 and 844<span class="elsevierStyleHsp" style=""></span>nm for the oct and tet sites in Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span> &#40;inverse spinel&#41; <a class="elsevierStyleCrossRef" href="#bib0875">&#91;87&#93;</a>&#44; respectively&#46;</p><elsevierMultimedia ident="fig0075"></elsevierMultimedia><p id="par0225" class="elsevierStylePara elsevierViewall"><a class="elsevierStyleCrossRef" href="#fig0080">Fig&#46; 16</a>&#40;a&#41; and &#40;b&#41; compares the PL spectra of Zn<span class="elsevierStyleInf">&#40;1&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05&#44; i&#46;e&#46; Zn<span class="elsevierStyleInf">&#40;0&#46;95&#41;</span>Fe<span class="elsevierStyleInf">0&#46;05</span><span class="elsevierStyleSup">3&#43;</span>Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and ZnAl<span class="elsevierStyleInf">&#40;1&#46;95&#41;</span>Fe<span class="elsevierStyleInf">0&#46;05</span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&#41;&#44; respectively&#44; taking into account the influence of charge compensation&#46; It is evident from <a class="elsevierStyleCrossRef" href="#fig0080">Fig&#46; 16</a> that the PL intensity of the sample where Fe<span class="elsevierStyleSup">3&#43;</span> substituted Al<span class="elsevierStyleSup">3&#43;</span> &#40;<a class="elsevierStyleCrossRef" href="#fig0080">Fig&#46; 16</a>&#40;b&#41;&#41; is about twice that of the sample where Fe<span class="elsevierStyleSup">3&#43;</span> substituted Zn<span class="elsevierStyleSup">2&#43;</span> &#40;<a class="elsevierStyleCrossRef" href="#fig0080">Fig&#46; 16</a>&#40;a&#41;&#41;&#46; The decreased luminescence intensity in <a class="elsevierStyleCrossRef" href="#fig0080">Fig&#46; 16</a>&#40;b&#41; is attributed to the charge imbalance in the matrix due to the substitution of divalent Zn<span class="elsevierStyleSup">2&#43;</span> ion by trivalent Fe<span class="elsevierStyleSup">3&#43;</span> ion&#46; Charge imbalance can lead to the formation of charge defects in the host lattice and hence creating non-radiative luminescence centers in the material <a class="elsevierStyleCrossRef" href="#bib0525">&#91;17&#93;</a>&#46;</p><elsevierMultimedia ident="fig0080"></elsevierMultimedia><p id="par0230" class="elsevierStylePara elsevierViewall"><a class="elsevierStyleCrossRef" href="#fig0085">Fig&#46; 17</a> shows CL spectra of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41;&#46; Generally&#44; the wavelengths of the CL peak maximum shifted with respect to the PL peaks&#46; The peak maximum observed at 487<span class="elsevierStyleHsp" style=""></span>nm in the PL result shifted to 503<span class="elsevierStyleHsp" style=""></span>nm for the undoped sample and 486<span class="elsevierStyleHsp" style=""></span>nm for the doped samples&#44; while the PL maximum observed at 730<span class="elsevierStyleHsp" style=""></span>nm shifted to 703<span class="elsevierStyleHsp" style=""></span>nm&#46; The shift observed in the wavelength maximum of the CL spectra compared to the PL spectra could be relate to the different excitation sources used to excite the samples in both cases&#46; During PL&#44; the charge carriers are excited using photons&#44; while the charge carriers in CL are excited using high-energy electrons&#46; CL can provide a better spatial resolution than PL&#44; this can be correlated to the small beam diameter &#40;&#60;10<span class="elsevierStyleHsp" style=""></span>nm&#41; of the electron beam <a class="elsevierStyleCrossRef" href="#bib0880">&#91;88&#93;</a>&#46; Similar to the PL spectra &#40;<a class="elsevierStyleCrossRef" href="#fig0065">Fig&#46; 13</a>&#40;a&#41;&#41;&#44; the band maximum observed at 503<span class="elsevierStyleHsp" style=""></span>nm in the undoped sample shifts to lower wavelength with increasing Fe<span class="elsevierStyleSup">3&#43;</span> concentration&#44; but the 703<span class="elsevierStyleHsp" style=""></span>nm peak remain at the similar position&#46;</p><elsevierMultimedia ident="fig0085"></elsevierMultimedia></span><span id="sec0030" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0050">Conclusion</span><p id="par0235" class="elsevierStylePara elsevierViewall">The Pechini synthesis method has proven to be an easy route to prepare ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> doped Fe<span class="elsevierStyleSup">3&#43;</span> phosphors&#46; The XRD results confirmed that the phosphors crystallized at a very low annealing temperature &#40;600<span class="elsevierStyleHsp" style=""></span>&#176;C&#41;&#46; The crystallite sizes estimated from the XRD data were smaller than the grain size estimated from the FE-SEM micrograph due to the formation of polycrystalline aggregates in the FE-SEM micrograph&#46; The oxygen parameter &#40;<span class="elsevierStyleItalic">u</span>&#41; and the inversion degrees &#40;<span class="elsevierStyleItalic">y</span>&#41; of the phosphors were estimated from the XRD data&#46; The XPS results confirmed the presence of Fe ions in both the tet and oct sites of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#46; Furthermore&#44; the XPS data also confirmed that Fe<span class="elsevierStyleSup">2&#43;</span> ions were present in the samples doped with Fe<span class="elsevierStyleSup">3&#43;</span>&#44; suggesting the reduction of some of the Fe<span class="elsevierStyleSup">3&#43;</span> ions to Fe<span class="elsevierStyleSup">2&#43;</span> ions&#46; From the diffuse reflectance data&#44; the band gaps of the phosphors estimated using the Kubelka&#8211;Munk equation and the derivative method gave similar values&#46; In agreement with the XPS result&#44; the PL and the CL study of the phosphors showed two broad bands at around 470 and 730<span class="elsevierStyleHsp" style=""></span>nm which were assigned to the <span class="elsevierStyleSup">4</span>E<span class="elsevierStyleHsp" style=""></span>&#43;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">4</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">4</span>G&#41;<span class="elsevierStyleHsp" style=""></span>&#8594;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">6</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">6</span>S&#41; and <span class="elsevierStyleSup">4</span>T<span class="elsevierStyleInf">2</span>&#40;<span class="elsevierStyleSup">4</span>G&#41;<span class="elsevierStyleHsp" style=""></span>&#8594;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleSup">6</span>A<span class="elsevierStyleInf">1</span>&#40;<span class="elsevierStyleSup">6</span>S&#41; electronic transitions of Fe<span class="elsevierStyleSup">3&#43;</span> ions occupying the tet and the oct sites in the spinel ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> host&#44; respectively&#46;</p></span></span>"
    "textoCompletoSecciones" => array:1 [
      "secciones" => array:10 [
        0 => array:3 [
          "identificador" => "xres1524490"
          "titulo" => "Abstract"
          "secciones" => array:1 [
            0 => array:1 [
              "identificador" => "abst0005"
            ]
          ]
        ]
        1 => array:2 [
          "identificador" => "xpalclavsec1382328"
          "titulo" => "Keywords"
        ]
        2 => array:3 [
          "identificador" => "xres1524491"
          "titulo" => "Resumen"
          "secciones" => array:1 [
            0 => array:1 [
              "identificador" => "abst0010"
            ]
          ]
        ]
        3 => array:2 [
          "identificador" => "xpalclavsec1382329"
          "titulo" => "Palabras clave"
        ]
        4 => array:2 [
          "identificador" => "sec0005"
          "titulo" => "Introduction"
        ]
        5 => array:3 [
          "identificador" => "sec0010"
          "titulo" => "Experimental"
          "secciones" => array:2 [
            0 => array:2 [
              "identificador" => "sec0015"
              "titulo" => "Synthesis"
            ]
            1 => array:2 [
              "identificador" => "sec0020"
              "titulo" => "Characterization"
            ]
          ]
        ]
        6 => array:2 [
          "identificador" => "sec0025"
          "titulo" => "Results and discussion"
        ]
        7 => array:2 [
          "identificador" => "sec0030"
          "titulo" => "Conclusion"
        ]
        8 => array:2 [
          "identificador" => "xack535380"
          "titulo" => "Acknowledgements"
        ]
        9 => array:1 [
          "titulo" => "References"
        ]
      ]
    ]
    "pdfFichero" => "main.pdf"
    "tienePdf" => true
    "fechaRecibido" => "2019-12-02"
    "fechaAceptado" => "2020-02-26"
    "PalabrasClave" => array:2 [
      "en" => array:1 [
        0 => array:4 [
          "clase" => "keyword"
          "titulo" => "Keywords"
          "identificador" => "xpalclavsec1382328"
          "palabras" => array:5 [
            0 => "Luminescence"
            1 => "Lifetime"
            2 => "Microscopy"
            3 => "Spectroscopy"
            4 => "Inversion degree"
          ]
        ]
      ]
      "es" => array:1 [
        0 => array:4 [
          "clase" => "keyword"
          "titulo" => "Palabras clave"
          "identificador" => "xpalclavsec1382329"
          "palabras" => array:6 [
            0 => "F&#243;sforos"
            1 => "Luminiscencia"
            2 => "Toda la vida"
            3 => "Microscop&#237;a"
            4 => "Espectroscopia"
            5 => "Grado de inversi&#243;n"
          ]
        ]
      ]
    ]
    "tieneResumen" => true
    "resumen" => array:2 [
      "en" => array:2 [
        "titulo" => "Abstract"
        "resumen" => "<span id="abst0005" class="elsevierStyleSection elsevierViewall"><p id="spar0005" class="elsevierStyleSimplePara elsevierViewall">ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> doped with various concentration &#40;<span class="elsevierStyleItalic">x</span>&#41; of Fe<span class="elsevierStyleSup">3&#43;</span> were prepared using the Pechini synthesis&#46; In the first set of samples&#44; Fe<span class="elsevierStyleSup">3&#43;</span> substituted Al<span class="elsevierStyleSup">3&#43;</span> to create a system of the form ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#8211;0&#46;08&#41;&#46; To study the effect of charge compensation&#44; Fe<span class="elsevierStyleSup">3&#43;</span> substituted Zn<span class="elsevierStyleSup">2&#43;</span> to create Zn<span class="elsevierStyleInf">&#40;1&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05&#41; system&#46; The structure and particle morphology of the phosphors were studied using X-ray diffractometer &#40;XRD&#41; and field emission scanning electron spectroscopy&#44; respectively&#46; From the XRD data&#44; the oxygen parameter and the inversion degrees were estimated&#46; The elemental composition and electronic states of the phosphors were analyzed using X-ray photoelectron spectroscopy &#40;XPS&#41;&#46; XPS results showed that part of the Fe<span class="elsevierStyleSup">3&#43;</span> were reduced to Fe<span class="elsevierStyleSup">2&#43;</span> in the doped samples&#46; Both photoluminescence and cathodoluminescence properties of the phosphors were also studied&#46; Luminescence excitations using a xenon lamp and X-ray showed two broad emission bands located around 470 and 730<span class="elsevierStyleHsp" style=""></span>nm&#44; and were ascribed to Fe ions occupying the tetrahedral &#40;tet&#41; and the octahedral &#40;oct&#41; sites in ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#44; respectively&#46; A change in the lifetime of these two emission bands upon Fe doping further confirmed the existence of Fe in the tet and oct sites in the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> matrix&#46;</p></span>"
      ]
      "es" => array:2 [
        "titulo" => "Resumen"
        "resumen" => "<span id="abst0010" class="elsevierStyleSection elsevierViewall"><p id="spar0010" class="elsevierStyleSimplePara elsevierViewall">Se prepar&#243; ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> dopado con varias concentraciones &#40;<span class="elsevierStyleItalic">x</span>&#41; de Fe<span class="elsevierStyleSup">3&#43;</span> usando la s&#237;ntesis de Pechini&#46; En el primer conjunto de muestras&#44; Fe<span class="elsevierStyleSup">3&#43;</span> sustituy&#243; Al<span class="elsevierStyleSup">3&#43;</span> para crear un sistema de la forma ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0 a 0&#44;08&#41;&#46; Para estudiar el efecto de la compensaci&#243;n de carga&#44; Fe<span class="elsevierStyleSup">3&#43;</span> sustituy&#243; Zn<span class="elsevierStyleSup">2&#43;</span> para crear el sistema Zn<span class="elsevierStyleInf">&#40;1&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44;05&#41;&#46; La estructura y la morfolog&#237;a de las part&#237;culas de los f&#243;sforos se estudiaron utilizando un difract&#243;metro de rayos X &#40;XRD&#41; y espectroscop&#237;a electr&#243;nica de barrido de emisi&#243;n de campo&#44; respectivamente&#46; A partir de los datos XRD se estimaron el par&#225;metro de ox&#237;geno y los grados de inversi&#243;n&#46; La composici&#243;n elemental y los estados electr&#243;nicos de los f&#243;sforos se analizaron mediante espectroscop&#237;a de fotoelectrones de rayos X &#40;XPS&#41;&#46; Los resultados de XPS mostraron que parte de Fe<span class="elsevierStyleSup">3&#43;</span> se redujo a Fe<span class="elsevierStyleSup">2&#43;</span> en las muestras dopadas&#46; Tambi&#233;n se estudiaron las propiedades de fotoluminiscencia y catodoluminiscencia de los f&#243;sforos&#46; Las excitaciones de luminiscencia usando una l&#225;mpara de xen&#243;n y rayos X mostraron dos amplias bandas de emisi&#243;n ubicadas alrededor de 470 y 730<span class="elsevierStyleHsp" style=""></span>nm&#44; y se atribuyeron a iones Fe que ocupan los sitios tetra&#233;dricos &#40;tet&#41; y octa&#233;drico &#40;oct&#41; en ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#44; respectivamente&#46; Un cambio en la vida &#250;til de estas dos bandas de emisi&#243;n despu&#233;s del dopaje con Fe confirm&#243; a&#250;n m&#225;s la existencia de Fe en los sitios tet y oct en la matriz ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&#46;</p></span>"
      ]
    ]
    "multimedia" => array:44 [
      0 => array:7 [
        "identificador" => "fig0005"
        "etiqueta" => "Fig&#46; 1"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr1.jpeg"
            "Alto" => 1143
            "Ancho" => 1500
            "Tamanyo" => 204759
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0015" class="elsevierStyleSimplePara elsevierViewall">Diagrammatic illustration of the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> spinel structure showing&#59; &#40;a&#41; a unit cell with five oct sites &#40;mint green&#41; and seven tet sites &#40;lilac blue&#41;&#44; &#40;b&#41; double tet and &#40;c&#41; oct coordinates&#46;</p>"
        ]
      ]
      1 => array:7 [
        "identificador" => "fig0010"
        "etiqueta" => "Fig&#46; 2"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr2.jpeg"
            "Alto" => 2344
            "Ancho" => 2341
            "Tamanyo" => 386882
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0020" class="elsevierStyleSimplePara elsevierViewall">The XRD patterns of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05 and 0&#46;08&#41; and the JCPDS standard&#46;</p>"
        ]
      ]
      2 => array:7 [
        "identificador" => "fig0015"
        "etiqueta" => "Fig&#46; 3"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr3.jpeg"
            "Alto" => 1091
            "Ancho" => 1508
            "Tamanyo" => 113205
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0025" class="elsevierStyleSimplePara elsevierViewall">A graph of the lattice parameter &#40;<span class="elsevierStyleItalic">a</span>&#41; of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; as a function of the Fe<span class="elsevierStyleSup">3&#43;</span> ion concentration&#46;</p>"
        ]
      ]
      3 => array:7 [
        "identificador" => "fig0020"
        "etiqueta" => "Fig&#46; 4"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr4.jpeg"
            "Alto" => 2407
            "Ancho" => 1508
            "Tamanyo" => 273593
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0030" class="elsevierStyleSimplePara elsevierViewall">The FE-SEM images of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;a&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0 and &#40;b&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;08&#46; The inset of &#40;a&#41; and &#40;b&#41; depicts the average particle size distribution curves for the images thereof&#46;</p>"
        ]
      ]
      4 => array:7 [
        "identificador" => "fig0025"
        "etiqueta" => "Fig&#46; 5"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr5.jpeg"
            "Alto" => 1769
            "Ancho" => 1508
            "Tamanyo" => 142249
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0035" class="elsevierStyleSimplePara elsevierViewall">The EDS spectra of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;a&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0 and &#40;b&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;08&#46; The inset of &#40;a&#41; and &#40;b&#41; are the at&#46;&#37; elemental concentration&#46;</p>"
        ]
      ]
      5 => array:7 [
        "identificador" => "fig0030"
        "etiqueta" => "Fig&#46; 6"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr6.jpeg"
            "Alto" => 2473
            "Ancho" => 2175
            "Tamanyo" => 317783
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0040" class="elsevierStyleSimplePara elsevierViewall">The fitted high-resolution O 1s XPS spectra of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&#44; &#40;a&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; &#40;b&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#44; &#40;c&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05 and &#40;d&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;08&#46;</p>"
        ]
      ]
      6 => array:7 [
        "identificador" => "fig0035"
        "etiqueta" => "Fig&#46; 7"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr7.jpeg"
            "Alto" => 2622
            "Ancho" => 2175
            "Tamanyo" => 372130
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0045" class="elsevierStyleSimplePara elsevierViewall">The fitted high-resolution Al 2p XPS spectra for ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&#44; &#40;a&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; &#40;b&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#44; &#40;c&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05 and &#40;d&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;08&#46;</p>"
        ]
      ]
      7 => array:7 [
        "identificador" => "fig0040"
        "etiqueta" => "Fig&#46; 8"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr8.jpeg"
            "Alto" => 2056
            "Ancho" => 2175
            "Tamanyo" => 339456
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0050" class="elsevierStyleSimplePara elsevierViewall">The fitted high-resolution Zn 2p XPS spectra of the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&#44; &#40;a&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; &#40;b&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#44; &#40;c&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05 and &#40;d&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;08&#46;</p>"
        ]
      ]
      8 => array:7 [
        "identificador" => "fig0045"
        "etiqueta" => "Fig&#46; 9"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr9.jpeg"
            "Alto" => 1329
            "Ancho" => 2091
            "Tamanyo" => 234303
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0055" class="elsevierStyleSimplePara elsevierViewall">&#40;a&#41; The fitted high-resolution Fe 2p XPS spectra of the ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58; 4&#37; Fe<span class="elsevierStyleSup">3&#43;</span>&#46; &#40;b&#41; The structural makeup of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58;Fe<span class="elsevierStyleSup">3&#43;</span>&#46;</p>"
        ]
      ]
      9 => array:7 [
        "identificador" => "fig0050"
        "etiqueta" => "Fig&#46; 10"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr10.jpeg"
            "Alto" => 1047
            "Ancho" => 1341
            "Tamanyo" => 132737
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0060" class="elsevierStyleSimplePara elsevierViewall">The diffuse reflectance spectra of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors&#46;</p>"
        ]
      ]
      10 => array:7 [
        "identificador" => "fig0055"
        "etiqueta" => "Fig&#46; 11"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr11.jpeg"
            "Alto" => 1874
            "Ancho" => 1508
            "Tamanyo" => 271961
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0065" class="elsevierStyleSimplePara elsevierViewall">The plots of <span class="elsevierStyleItalic">dR</span>&#47;<span class="elsevierStyleItalic">dE</span> versus <span class="elsevierStyleItalic">E</span> &#40;eV&#41; for the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors&#46;</p>"
        ]
      ]
      11 => array:7 [
        "identificador" => "fig0060"
        "etiqueta" => "Fig&#46; 12"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr12.jpeg"
            "Alto" => 1109
            "Ancho" => 2091
            "Tamanyo" => 239928
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0070" class="elsevierStyleSimplePara elsevierViewall">The plot of &#40;F&#40;R100&#41;hv&#41;2 versus <span class="elsevierStyleItalic">hv</span> for the ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&#44; &#40;a&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; &#40;b&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&#44; &#40;c&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;025&#44; &#40;d&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05&#44; and &#40;e&#41; <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;08&#46;</p>"
        ]
      ]
      12 => array:7 [
        "identificador" => "fig0065"
        "etiqueta" => "Fig&#46; 13"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr13.jpeg"
            "Alto" => 2129
            "Ancho" => 1508
            "Tamanyo" => 295041
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0075" class="elsevierStyleSimplePara elsevierViewall">The PL &#40;a&#41; excitation &#40;under 487<span class="elsevierStyleHsp" style=""></span>nm emission&#41; and &#40;b&#41; emission &#40;under 235<span class="elsevierStyleHsp" style=""></span>nm excitation&#41; spectra of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors normalized with respect to the dopant concentration&#46; The inset of &#40;a&#41; shows the variation of the 487 and 730<span class="elsevierStyleHsp" style=""></span>nm bands as a function of Fe<span class="elsevierStyleSup">3&#43;</span> concentration&#46;</p>"
        ]
      ]
      13 => array:7 [
        "identificador" => "fig0070"
        "etiqueta" => "Fig&#46; 14"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr14.jpeg"
            "Alto" => 2101
            "Ancho" => 1508
            "Tamanyo" => 319579
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0080" class="elsevierStyleSimplePara elsevierViewall">The decays curves for ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors when monitoring &#40;a&#41; 487<span class="elsevierStyleHsp" style=""></span>nm and &#40;b&#41; 730<span class="elsevierStyleHsp" style=""></span>nm emission under 235<span class="elsevierStyleHsp" style=""></span>nm excitation&#46; The insets of &#40;a&#41; and &#40;b&#41; are the plot of the average lifetime of the phosphors versus the Fe<span class="elsevierStyleSup">3&#43;</span> concentration &#40;<span class="elsevierStyleItalic">x</span>&#41; for the 487<span class="elsevierStyleHsp" style=""></span>nm emission and 730<span class="elsevierStyleHsp" style=""></span>nm emissions&#44; respectively&#46;</p>"
        ]
      ]
      14 => array:7 [
        "identificador" => "fig0075"
        "etiqueta" => "Fig&#46; 15"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr15.jpeg"
            "Alto" => 2081
            "Ancho" => 1508
            "Tamanyo" => 317976
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0085" class="elsevierStyleSimplePara elsevierViewall">Schematic energy diagrams showing&#44; &#40;a&#41; the emission of Fe&#44; zinc interstitials and oxygen vacancies in ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> host and &#40;b&#41; the electronic transitions Fe ions &#40;Fe<span class="elsevierStyleSup">3&#43;</span> and Fe<span class="elsevierStyleSup">2&#43;</span>&#41; on the tet and the oct sites of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> host&#46;</p>"
        ]
      ]
      15 => array:7 [
        "identificador" => "fig0080"
        "etiqueta" => "Fig&#46; 16"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr16.jpeg"
            "Alto" => 950
            "Ancho" => 1341
            "Tamanyo" => 116270
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0090" class="elsevierStyleSimplePara elsevierViewall">The PL emission spectra of &#40;a&#41; Zn<span class="elsevierStyleInf">&#40;1&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and &#40;b&#41; ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> for <span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05&#44; excited at 235<span class="elsevierStyleHsp" style=""></span>nm&#46;</p>"
        ]
      ]
      16 => array:7 [
        "identificador" => "fig0085"
        "etiqueta" => "Fig&#46; 17"
        "tipo" => "MULTIMEDIAFIGURA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "figura" => array:1 [
          0 => array:4 [
            "imagen" => "gr17.jpeg"
            "Alto" => 1948
            "Ancho" => 1508
            "Tamanyo" => 267848
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0095" class="elsevierStyleSimplePara elsevierViewall">The CL spectra of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleItalic"><span class="elsevierStyleInf">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors&#46;</p>"
        ]
      ]
      17 => array:8 [
        "identificador" => "tbl0005"
        "etiqueta" => "Table 1"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "detalles" => array:1 [
          0 => array:3 [
            "identificador" => "at1"
            "detalle" => "Table "
            "rol" => "short"
          ]
        ]
        "tabla" => array:1 [
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Ions&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Tet ionic radius &#40;nm&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Oct ionic radius &#40;nm&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Ref&#46;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Zn<span class="elsevierStyleSup">2&#43;</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;06&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;074&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Al<span class="elsevierStyleSup">3&#43;</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;039&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;054&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><a class="elsevierStyleCrossRef" href="#bib0570">&#91;26&#93;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Fe<span class="elsevierStyleSup">3&#43;</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;049&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;065&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Fe<span class="elsevierStyleSup">2&#43;</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;063&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;078&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab2620339.png"
              ]
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0100" class="elsevierStyleSimplePara elsevierViewall">The ionic radii of Zn<span class="elsevierStyleSup">2&#43;</span>&#44; Al<span class="elsevierStyleSup">3&#43;</span>&#44; Fe<span class="elsevierStyleSup">3&#43;</span> and Fe<span class="elsevierStyleSup">2&#43;</span> in the tet and oct coordinates&#46;</p>"
        ]
      ]
      18 => array:8 [
        "identificador" => "tbl0010"
        "etiqueta" => "Table 2"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "detalles" => array:1 [
          0 => array:3 [
            "identificador" => "at2"
            "detalle" => "Table "
            "rol" => "short"
          ]
        ]
        "tabla" => array:1 [
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Crystallite size &#40;<span class="elsevierStyleItalic">L</span>&#41; &#40;nm&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Strain &#40;<span class="elsevierStyleItalic">&#603;</span>&#41;<span class="elsevierStyleHsp" style=""></span>&#215;<span class="elsevierStyleHsp" style=""></span><span class="elsevierStyleItalic">e</span><span class="elsevierStyleSup">&#8722;4</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">27&#46;8&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">10&#46;8&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">33&#46;5&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">11&#46;2&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;025&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">41&#46;8&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">14&#46;7&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">80&#46;6&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">17&#46;6&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;08&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">86&#46;6&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">17&#46;6&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab2620337.png"
              ]
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0105" class="elsevierStyleSimplePara elsevierViewall">Estimated crystallite sizes and strain of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05&#44; 0&#46;08&#41; phosphors&#46;</p>"
        ]
      ]
      19 => array:8 [
        "identificador" => "tbl0015"
        "etiqueta" => "Table 3"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "detalles" => array:1 [
          0 => array:3 [
            "identificador" => "at3"
            "detalle" => "Table "
            "rol" => "short"
          ]
        ]
        "tabla" => array:2 [
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black"><span class="elsevierStyleItalic">X</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black"><span class="elsevierStyleItalic">a</span> &#40;&#8491;&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black"><span class="elsevierStyleItalic">u</span> &#40;literature&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black"><span class="elsevierStyleItalic">u</span> &#40;calculated&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black"><span class="elsevierStyleItalic">y</span> &#40;literature&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black"><span class="elsevierStyleItalic">y</span> &#40;calculated&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8&#46;054<span class="elsevierStyleHsp" style=""></span>&#177;<span class="elsevierStyleHsp" style=""></span>0&#46;001&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;261<a class="elsevierStyleCrossRef" href="#tblfn0005">&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;00<a class="elsevierStyleCrossRef" href="#tblfn0005">&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;01&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8&#46;060<span class="elsevierStyleHsp" style=""></span>&#177;<span class="elsevierStyleHsp" style=""></span>0&#46;001&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;261&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;04&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;025&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8&#46;066<span class="elsevierStyleHsp" style=""></span>&#177;<span class="elsevierStyleHsp" style=""></span>0&#46;001&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;262&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;08&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;05&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8&#46;075<span class="elsevierStyleHsp" style=""></span>&#177;<span class="elsevierStyleHsp" style=""></span>0&#46;001&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;262&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;11&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;08&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8&#46;085<span class="elsevierStyleHsp" style=""></span>&#177;<span class="elsevierStyleHsp" style=""></span>0&#46;001&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;262&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;15&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8&#46;392<a class="elsevierStyleCrossRef" href="#tblfn0005">&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;255<a class="elsevierStyleCrossRef" href="#tblfn0005">&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&#46;00<a class="elsevierStyleCrossRef" href="#tblfn0005">&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab2620340.png"
              ]
            ]
          ]
          "notaPie" => array:1 [
            0 => array:3 [
              "identificador" => "tblfn0005"
              "etiqueta" => "&#42;"
              "nota" => "<p class="elsevierStyleNotepara" id="npar0005"><a class="elsevierStyleCrossRef" href="#bib0590">&#91;30&#93;</a>&#46;</p>"
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0110" class="elsevierStyleSimplePara elsevierViewall">The lattice parameters and inversion degree of different spinel composition&#46;</p>"
        ]
      ]
      20 => array:8 [
        "identificador" => "tbl0020"
        "etiqueta" => "Table 4"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "detalles" => array:1 [
          0 => array:3 [
            "identificador" => "at4"
            "detalle" => "Table "
            "rol" => "short"
          ]
        ]
        "tabla" => array:2 [
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Cation&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Rtet &#40;calculated&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Rtet &#40;literature&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Roct &#40;calculated&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Roct &#40;literature&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Zn<span class="elsevierStyleSup">2&#43;</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&#46;8971&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&#46;9493<a class="elsevierStyleCrossRef" href="#tblfn0015">&#42;&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Fe<span class="elsevierStyleSup">2&#43;</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&#46;9950<a class="elsevierStyleCrossRef" href="#tblfn0010">&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">2&#46;0996&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">2&#46;0800<a class="elsevierStyleCrossRef" href="#tblfn0020">&#42;&#42;&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Fe<span class="elsevierStyleSup">3&#43;</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&#46;8867&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">2&#46;0175&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">2&#46;0300<a class="elsevierStyleCrossRef" href="#tblfn0020">&#42;&#42;&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">Al<span class="elsevierStyleSup">3&#43;</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">&#8211;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&#46;9289&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">1&#46;9169<a class="elsevierStyleCrossRef" href="#tblfn0015">&#42;&#42;</a>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab2620338.png"
              ]
            ]
          ]
          "notaPie" => array:3 [
            0 => array:3 [
              "identificador" => "tblfn0010"
              "etiqueta" => "&#42;"
              "nota" => "<p class="elsevierStyleNotepara" id="npar0010"><a class="elsevierStyleCrossRef" href="#bib0590">&#91;30&#93;</a>&#46;</p>"
            ]
            1 => array:3 [
              "identificador" => "tblfn0015"
              "etiqueta" => "&#42;&#42;"
              "nota" => "<p class="elsevierStyleNotepara" id="npar0015"><a class="elsevierStyleCrossRef" href="#bib0615">&#91;35&#93;</a>&#46;</p>"
            ]
            2 => array:3 [
              "identificador" => "tblfn0020"
              "etiqueta" => "&#42;&#42;&#42;"
              "nota" => "<p class="elsevierStyleNotepara" id="npar0020"><a class="elsevierStyleCrossRef" href="#bib0620">&#91;36&#93;</a>&#46;</p>"
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0115" class="elsevierStyleSimplePara elsevierViewall">Calculated bond lengths of the cations-O in ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> system in the tet and oct sites compared to the literatures&#46;</p>"
        ]
      ]
      21 => array:8 [
        "identificador" => "tbl0025"
        "etiqueta" => "Table 5"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "detalles" => array:1 [
          0 => array:3 [
            "identificador" => "at5"
            "detalle" => "Table "
            "rol" => "short"
          ]
        ]
        "tabla" => array:1 [
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td-with-role" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col">Samples&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " colspan="4" align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Elements&#47;compositions &#40;at&#46;&#37;&#41;</th></tr><tr title="table-row"><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Zn&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Al&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">O&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Fe&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">14&#46;4&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">27&#46;6&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">58&#46;0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">14&#46;5&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">28&#46;0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">57&#46;5&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;025&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">14&#46;6&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">28&#46;3&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">57&#46;1&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">14&#46;6&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">28&#46;2&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">57&#46;1&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;1&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;08&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">14&#46;6&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">28&#46;0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">57&#46;3&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;1&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab2620336.png"
              ]
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0120" class="elsevierStyleSimplePara elsevierViewall">Elemental composition and concentration ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span> phosphors &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05 and 0&#46;08&#41;&#46;</p>"
        ]
      ]
      22 => array:8 [
        "identificador" => "tbl0030"
        "etiqueta" => "Table 6"
        "tipo" => "MULTIMEDIATABLA"
        "mostrarFloat" => true
        "mostrarDisplay" => false
        "detalles" => array:1 [
          0 => array:3 [
            "identificador" => "at6"
            "detalle" => "Table "
            "rol" => "short"
          ]
        ]
        "tabla" => array:1 [
          "tablatextoimagen" => array:1 [
            0 => array:2 [
              "tabla" => array:1 [
                0 => """
                  <table border="0" frame="\n
                  \t\t\t\t\tvoid\n
                  \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td-with-role" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col">ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span>O<span class="elsevierStyleInf">4</span>&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " colspan="2" align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Average lifetime &#40;ms&#41;&#44; <span class="elsevierStyleItalic">&#955;</span><span class="elsevierStyleInf">Exc&#46;</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>235<span class="elsevierStyleHsp" style=""></span>nm</th></tr><tr title="table-row"><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black">&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black"><span class="elsevierStyleItalic">&#955;</span><span class="elsevierStyleInf">Emi&#46;</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>487<span class="elsevierStyleHsp" style=""></span>nm&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th><th class="td" title="\n
                  \t\t\t\t\ttable-head\n
                  \t\t\t\t  " align="center" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t" scope="col" style="border-bottom: 2px solid black"><span class="elsevierStyleItalic">&#955;</span><span class="elsevierStyleInf">Emi&#46;</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>730<span class="elsevierStyleHsp" style=""></span>nm&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;21&#40;3&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">6&#46;4&#40;9&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;01&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;20&#40;3&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8&#46;2&#40;3&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;025&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;20&#40;2&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">7&#46;8&#40;4&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;05&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;20&#40;4&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8&#46;0&#40;4&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t"><span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#46;08&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">0&#46;20&#40;1&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td><td class="td" title="\n
                  \t\t\t\t\ttable-entry\n
                  \t\t\t\t  " align="char" valign="\n
                  \t\t\t\t\ttop\n
                  \t\t\t\t">8&#46;2&#40;1&#41;&nbsp;\t\t\t\t\t\t\n
                  \t\t\t\t</td></tr></tbody></table>
                  """
              ]
              "imagenFichero" => array:1 [
                0 => "xTab2620335.png"
              ]
            ]
          ]
        ]
        "descripcion" => array:1 [
          "en" => "<p id="spar0125" class="elsevierStyleSimplePara elsevierViewall">The average lifetime of ZnAl<span class="elsevierStyleInf">&#40;2&#8722;<span class="elsevierStyleItalic">x</span>&#41;</span>Fe<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span><span class="elsevierStyleSup">3&#43;</span> O<span class="elsevierStyleInf">4</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#44; 0&#46;01&#44; 0&#46;025&#44; 0&#46;05 and 0&#46;08&#41; for 487 and 730<span class="elsevierStyleHsp" style=""></span>nm emissions&#44; when monitoring the excitation at 235<span class="elsevierStyleHsp" style=""></span>nm&#46;</p>"
        ]
      ]
      23 => array:6 [
        "identificador" => "eq0005"
        "etiqueta" => "&#40;1&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "&#946;h&#8201;k&#8201;l&#8201;Cos&#8201;&#952;&#61;&#954;&#955;L&#43;4&#949;&#8201;Sin&#8201;&#952;"
          "Fichero" => "STRIPIN_si4.jpeg"
          "Tamanyo" => 1721
          "Alto" => 30
          "Ancho" => 166
        ]
      ]
      24 => array:6 [
        "identificador" => "eq0010"
        "etiqueta" => "&#40;2&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "a2&#61;d2&#40;h2&#43;k2&#43;l2&#41;"
          "Fichero" => "STRIPIN_si9.jpeg"
          "Tamanyo" => 1187
          "Alto" => 17
          "Ancho" => 133
        ]
      ]
      25 => array:6 [
        "identificador" => "eq0015"
        "etiqueta" => "&#40;3&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "d&#61;&#955;2&#8201;Sin&#8201;&#952;"
          "Fichero" => "STRIPIN_si10.jpeg"
          "Tamanyo" => 974
          "Alto" => 30
          "Ancho" => 71
        ]
      ]
      26 => array:6 [
        "identificador" => "eq0020"
        "etiqueta" => "&#40;4&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "Rtet&#61;a3u&#8722;18"
          "Fichero" => "STRIPIN_si11.jpeg"
          "Tamanyo" => 1470
          "Alto" => 40
          "Ancho" => 133
        ]
      ]
      27 => array:6 [
        "identificador" => "eq0025"
        "etiqueta" => "&#40;5&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "Roct&#61;a3u2&#8722;2u&#43;1381&#47;2"
          "Fichero" => "STRIPIN_si12.jpeg"
          "Tamanyo" => 1970
          "Alto" => 43
          "Ancho" => 187
        ]
      ]
      28 => array:6 [
        "identificador" => "eq0030"
        "etiqueta" => "&#91;1&#93;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "&#40;Zn82&#43;&#41;tet&#91;Al163&#43;&#93;octO32"
          "Fichero" => "STRIPIN_si13.jpeg"
          "Tamanyo" => 1656
          "Alto" => 19
          "Ancho" => 147
        ]
      ]
      29 => array:6 [
        "identificador" => "eq0035"
        "etiqueta" => "&#91;2&#93;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "&#40;Fe83&#43;&#41;tet&#91;F83&#43;F82&#43;&#93;octO32"
          "Fichero" => "STRIPIN_si14.jpeg"
          "Tamanyo" => 1548
          "Alto" => 18
          "Ancho" => 159
        ]
      ]
      30 => array:6 [
        "identificador" => "eq0040"
        "etiqueta" => "&#91;3&#93;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "&#40;Zn8&#8722;x2&#43;Fex3&#43;&#41;tet&#91;Al8&#8722;x3&#43;Fex3&#43;F82&#43;&#93;octO32"
          "Fichero" => "STRIPIN_si15.jpeg"
          "Tamanyo" => 2717
          "Alto" => 19
          "Ancho" => 267
        ]
      ]
      31 => array:6 [
        "identificador" => "eq0045"
        "etiqueta" => "&#40;6&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "Rtet&#61;&#8721;iziRi"
          "Fichero" => "STRIPIN_si16.jpeg"
          "Tamanyo" => 1069
          "Alto" => 35
          "Ancho" => 89
        ]
      ]
      32 => array:6 [
        "identificador" => "eq0050"
        "etiqueta" => "&#40;7&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "Rtet&#61;0&#46;99RZn2&#43;&#44;tet&#43;yRFe3&#43;&#44;tet&#43;&#40;0&#46;01&#8722;y&#41;RFe2&#43;&#44;tet"
          "Fichero" => "STRIPIN_si17.jpeg"
          "Tamanyo" => 2446
          "Alto" => 17
          "Ancho" => 320
        ]
      ]
      33 => array:6 [
        "identificador" => "eq0055"
        "etiqueta" => "&#40;8&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "Roct&#61;1&#46;99RAl3&#43;&#44;oct&#43;&#40;0&#46;01&#8722;y&#41;RFe3&#43;&#44;oct&#43;yRFe2&#43;&#44;oct2"
          "Fichero" => "STRIPIN_si18.jpeg"
          "Tamanyo" => 3100
          "Alto" => 34
          "Ancho" => 325
        ]
      ]
      34 => array:6 [
        "identificador" => "eq0060"
        "etiqueta" => "&#40;9&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "&#40;&#945;hv&#41;1&#47;n&#61;A&#40;hv&#8722;Eg&#41;"
          "Fichero" => "STRIPIN_si20.jpeg"
          "Tamanyo" => 1327
          "Alto" => 20
          "Ancho" => 140
        ]
      ]
      35 => array:6 [
        "identificador" => "eq0065"
        "etiqueta" => "&#40;10&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "&#945;&#61;A&#40;hv&#8722;Eg&#41;nhv"
          "Fichero" => "STRIPIN_si21.jpeg"
          "Tamanyo" => 1344
          "Alto" => 34
          "Ancho" => 108
        ]
      ]
      36 => array:6 [
        "identificador" => "eq0070"
        "etiqueta" => "&#40;11&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "&#945;&#40;hv&#41;&#61;A&#40;hv&#8722;Eg&#41;nhv"
          "Fichero" => "STRIPIN_si23.jpeg"
          "Tamanyo" => 1675
          "Alto" => 34
          "Ancho" => 134
        ]
      ]
      37 => array:6 [
        "identificador" => "eq0075"
        "etiqueta" => "&#40;12&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "d&#945;&#40;hv&#41;d&#40;hv&#41;&#61;Ahv&#8722;&#40;hv&#8722;Eg&#41;nhv&#43;n&#40;hv&#8722;Eg&#41;n&#8722;1&#8195;hv&#62;Eg"
          "Fichero" => "STRIPIN_si24.jpeg"
          "Tamanyo" => 4228
          "Alto" => 40
          "Ancho" => 371
        ]
      ]
      38 => array:6 [
        "identificador" => "eq0080"
        "etiqueta" => "&#40;13&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "d&#945;&#40;hv&#41;d&#40;hv&#41;E&#61;Eg&#8594;&#8734;&#8195;n&#61;1&#47;2"
          "Fichero" => "STRIPIN_si25.jpeg"
          "Tamanyo" => 1909
          "Alto" => 44
          "Ancho" => 181
        ]
      ]
      39 => array:6 [
        "identificador" => "eq0085"
        "etiqueta" => "&#40;14&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "F&#40;R&#8734;&#41;&#61;&#40;1&#8722;R&#8734;&#41;22R&#8734;"
          "Fichero" => "STRIPIN_si26.jpeg"
          "Tamanyo" => 1979
          "Alto" => 41
          "Ancho" => 145
        ]
      ]
      40 => array:6 [
        "identificador" => "eq0090"
        "etiqueta" => "&#40;15&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "F&#40;R100&#41;&#61;&#40;1&#8722;R100&#41;22R100"
          "Fichero" => "STRIPIN_si28.jpeg"
          "Tamanyo" => 2284
          "Alto" => 41
          "Ancho" => 157
        ]
      ]
      41 => array:6 [
        "identificador" => "eq0095"
        "etiqueta" => "&#40;16&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "&#40;F&#40;R100&#41;hv&#41;1&#47;n&#61;A&#40;hv&#8722;Eg&#41;"
          "Fichero" => "STRIPIN_si31.jpeg"
          "Tamanyo" => 1656
          "Alto" => 20
          "Ancho" => 174
        ]
      ]
      42 => array:6 [
        "identificador" => "eq0100"
        "etiqueta" => "&#40;17&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "I&#61;A&#8201;exp&#8722;t&#964;1&#43;B&#8201;exp&#8722;t&#964;2&#43;&#8722;t&#964;3"
          "Fichero" => "STRIPIN_si32.jpeg"
          "Tamanyo" => 3151
          "Alto" => 40
          "Ancho" => 296
        ]
      ]
      43 => array:6 [
        "identificador" => "eq0105"
        "etiqueta" => "&#40;18&#41;"
        "tipo" => "MULTIMEDIAFORMULA"
        "mostrarFloat" => false
        "mostrarDisplay" => true
        "Formula" => array:5 [
          "Matematica" => "&#964;&#42;&#61;A&#964;12&#43;B&#964;22&#43;C&#964;32A&#964;1&#43;B&#964;2&#43;C&#964;3"
          "Fichero" => "STRIPIN_si37.jpeg"
          "Tamanyo" => 2409
          "Alto" => 35
          "Ancho" => 141
        ]
      ]
    ]
    "bibliografia" => array:2 [
      "titulo" => "References"
      "seccion" => array:1 [
        0 => array:2 [
          "identificador" => "bibs0015"
          "bibliografiaReferencia" => array:88 [
            0 => array:3 [
              "identificador" => "bib0445"
              "etiqueta" => "&#91;1&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Luminescence properties of ZnGa<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> spinels doped with Eu<span class="elsevierStyleSup">3&#43;</span> and Tb<span class="elsevierStyleSup">3&#43;</span> ions"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Phys&#46; Stat&#46; Solidi C"
                        "fecha" => "2009"
                        "volumen" => "6"
                        "paginaInicial" => "1199"
                        "paginaFinal" => "1202"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            1 => array:3 [
              "identificador" => "bib0450"
              "etiqueta" => "&#91;2&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Photoluminescence and EPR studies on Fe<span class="elsevierStyleSup">3&#43;</span> doped ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58; an evidence for local site swapping of Fe<span class="elsevierStyleSup">3&#43;</span> and formation of inverse and normal phase"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1039/c4dt00741g"
                      "Revista" => array:6 [
                        "tituloSerie" => "Dalton Trans&#46;"
                        "fecha" => "2014"
                        "volumen" => "43"
                        "paginaInicial" => "9313"
                        "paginaFinal" => "9323"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            2 => array:3 [
              "identificador" => "bib0455"
              "etiqueta" => "&#91;3&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Dynamics of the cation mixing of MgAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> spinel"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Am&#46; Ceram&#46; Soc&#46;"
                        "fecha" => "1999"
                        "volumen" => "82"
                        "paginaInicial" => "1844"
                        "paginaFinal" => "1848"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            3 => array:3 [
              "identificador" => "bib0460"
              "etiqueta" => "&#91;4&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Structure of spinel"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Am&#46; Ceram&#46; Soc&#46;"
                        "fecha" => "1999"
                        "volumen" => "82"
                        "paginaInicial" => "3279"
                        "paginaFinal" => "3292"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            4 => array:3 [
              "identificador" => "bib0465"
              "etiqueta" => "&#91;5&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Materials science for the experimental mechanist"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "LibroEditado" => array:4 [
                        "editores" => "W&#46;N&#46;SharpeJr&#46;"
                        "titulo" => "Springer Handbook of Experimental Solid Mechanics"
                        "paginaInicial" => "25"
                        "serieFecha" => "2008"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            5 => array:3 [
              "identificador" => "bib0470"
              "etiqueta" => "&#91;6&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Relation of A<span class="elsevierStyleSup">II</span>B<span class="elsevierStyleSup">III</span><span class="elsevierStyleInf">2</span>X<span class="elsevierStyleSup">VI</span><span class="elsevierStyleInf">4</span> compounds to other materials their properties and applications"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "LibroEditado" => array:5 [
                        "editores" => "F&#46;J&#46;Manjon, I&#46;Tiginyanu, V&#46;Ursaki"
                        "titulo" => "Pressure-induced Phase Transitions in AB<span class="elsevierStyleInf">2</span>X<span class="elsevierStyleInf">4</span> Chalcogenide Compounds"
                        "paginaInicial" => "1"
                        "paginaFinal" => "50"
                        "serieFecha" => "2014"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            6 => array:3 [
              "identificador" => "bib0475"
              "etiqueta" => "&#91;7&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "A comparison between rare earth and transition metals working as magnetic materials in an AMR refrigerator in the room temperature range"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Appl&#46; Therm&#46; Eng&#46;"
                        "fecha" => "2015"
                        "volumen" => "91"
                        "paginaInicial" => "767"
                        "paginaFinal" => "777"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            7 => array:3 [
              "identificador" => "bib0480"
              "etiqueta" => "&#91;8&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Fe<span class="elsevierStyleSup">3&#43;</span> red phosphors based on lithium aluminates and an aluminum lithium oxyfluoride prepared from LiF as the Li source"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Lumin&#46;"
                        "fecha" => "2017"
                        "volumen" => "182"
                        "paginaInicial" => "53"
                        "paginaFinal" => "58"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            8 => array:3 [
              "identificador" => "bib0485"
              "etiqueta" => "&#91;9&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Color-tunable luminescence and energy transfer of Eu<span class="elsevierStyleSup">2&#43;</span>&#47;Mn<span class="elsevierStyleSup">2&#43;</span> co-doped Sr<span class="elsevierStyleInf">9</span>Lu&#40;PO<span class="elsevierStyleInf">4</span>&#41;<span class="elsevierStyleInf">7</span> phosphors for white LEDs"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Polyhedron"
                        "fecha" => "2018"
                        "volumen" => "141"
                        "paginaInicial" => "284"
                        "paginaFinal" => "288"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            9 => array:3 [
              "identificador" => "bib0490"
              "etiqueta" => "&#91;10&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Luminescence lifetime thermometry with Mn<span class="elsevierStyleSup">3&#43;</span>&#8211;Mn<span class="elsevierStyleSup">4&#43;</span> co-doped nanocrystals"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Mater&#46; Chem&#46; C"
                        "fecha" => "2018"
                        "volumen" => "6"
                        "paginaInicial" => "7092"
                        "paginaFinal" => "7100"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            10 => array:3 [
              "identificador" => "bib0495"
              "etiqueta" => "&#91;11&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Transition metal-doped chalcogenide glasses for broadband near-infrared sources"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "LibroEditado" => array:5 [
                        "editores" => "A&#46;C&#46;J&#46;A&#46;C&#46;Terry, W&#46;A&#46;Clarkson"
                        "titulo" => "Solid State Laser Technologies and Femtosecond Phenomena&#44; SPIE&#44; vol&#46; 5620"
                        "paginaInicial" => "289"
                        "paginaFinal" => "296"
                        "serieFecha" => "2004"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            11 => array:3 [
              "identificador" => "bib0500"
              "etiqueta" => "&#91;12&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Laser materials based on transition metal ions"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Opt&#46; Mater&#46;"
                        "fecha" => "2017"
                        "volumen" => "63"
                        "paginaInicial" => "105"
                        "paginaFinal" => "117"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            12 => array:3 [
              "identificador" => "bib0505"
              "etiqueta" => "&#91;13&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Oxyfluoride glass-ceramics for transition metal Ion based photonics&#58; broadband near-IR luminescence of nickel ion dopant and nanocrystallization mechanism"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Phys&#46; Chem&#46; C"
                        "fecha" => "2016"
                        "volumen" => "120"
                        "paginaInicial" => "4556"
                        "paginaFinal" => "4563"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            13 => array:3 [
              "identificador" => "bib0510"
              "etiqueta" => "&#91;14&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Laser-related spectroscopy of ion-doped crystals for tunable solid-state lasers"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Appl&#46; Phys&#46; B"
                        "fecha" => "2001"
                        "volumen" => "72"
                        "paginaInicial" => "515"
                        "paginaFinal" => "562"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            14 => array:3 [
              "identificador" => "bib0515"
              "etiqueta" => "&#91;15&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Photoluminescence of the Mg<span class="elsevierStyleInf">2</span>Al<span class="elsevierStyleInf">4</span>Si<span class="elsevierStyleInf">5</span>O<span class="elsevierStyleInf">18</span>&#8211;Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span>&#8211;MgAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#8211;SiO<span class="elsevierStyleInf">2</span> ceramic system containing Fe<span class="elsevierStyleSup">3&#43;</span> and Cr<span class="elsevierStyleSup">3&#43;</span> as impurity ions"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Opt&#46; Mater&#46;"
                        "fecha" => "2018"
                        "volumen" => "76"
                        "paginaInicial" => "353"
                        "paginaFinal" => "358"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            15 => array:3 [
              "identificador" => "bib0520"
              "etiqueta" => "&#91;16&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Fe in III&#8211;V and II&#8211;VI semiconductors"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Phys&#46; Stat&#46; Sol&#46; &#40;b&#41;"
                        "fecha" => "2008"
                        "volumen" => "245"
                        "paginaInicial" => "455"
                        "paginaFinal" => "480"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            16 => array:3 [
              "identificador" => "bib0525"
              "etiqueta" => "&#91;17&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "The effects of charge compensation on photoluminescence properties of a new green-emitting ZnB<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58;Tb<span class="elsevierStyleSup">3&#43;</span> phosphor"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1002/bio.2634"
                      "Revista" => array:6 [
                        "tituloSerie" => "Luminescence"
                        "fecha" => "2014"
                        "volumen" => "29"
                        "paginaInicial" => "868"
                        "paginaFinal" => "871"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            17 => array:3 [
              "identificador" => "bib0530"
              "etiqueta" => "&#91;18&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Excitonics of semiconductor quantum dots and wires for lighting and displays"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Laser Photon&#46; Rev&#46;"
                        "fecha" => "2014"
                        "volumen" => "8"
                        "paginaInicial" => "73"
                        "paginaFinal" => "93"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            18 => array:3 [
              "identificador" => "bib0535"
              "etiqueta" => "&#91;19&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Improved optical photoluminescence by charge compensation in the phosphor system CaMoO<span class="elsevierStyleInf">4</span>&#58;Eu<span class="elsevierStyleSup">3&#43;</span>"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Opt&#46; Mater&#46;"
                        "fecha" => "2007"
                        "volumen" => "29"
                        "paginaInicial" => "1591"
                        "paginaFinal" => "1594"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            19 => array:3 [
              "identificador" => "bib0540"
              "etiqueta" => "&#91;20&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Effects of charge compensation on the luminescence behaviour of Eu<span class="elsevierStyleSup">3&#43;</span> activated CaWO<span class="elsevierStyleInf">4</span> phosphor"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Opt&#46; Mater&#46;"
                        "fecha" => "2008"
                        "volumen" => "30"
                        "paginaInicial" => "1616"
                        "paginaFinal" => "1620"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            20 => array:3 [
              "identificador" => "bib0545"
              "etiqueta" => "&#91;21&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Improved optical photoluminescence by charge compensation and luminescence tuning in Ca<span class="elsevierStyleInf">6</span>Ba&#40;PO<span class="elsevierStyleInf">4</span>&#41;<span class="elsevierStyleInf">4</span>O&#58;Ce<span class="elsevierStyleSup">3&#43;</span>&#44; Eu<span class="elsevierStyleSup">2&#43;</span> phosphors"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Cryst&#46; Eng&#46; Comm&#46;"
                        "fecha" => "2015"
                        "volumen" => "17"
                        "paginaInicial" => "8632"
                        "paginaFinal" => "8638"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            21 => array:3 [
              "identificador" => "bib0550"
              "etiqueta" => "&#91;22&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Structural and photophysical investigations of bright yellow emitting Dy&#58; ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> nanophosphor"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Lumin&#46;"
                        "fecha" => "2016"
                        "volumen" => "178"
                        "paginaInicial" => "407"
                        "paginaFinal" => "413"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            22 => array:3 [
              "identificador" => "bib0555"
              "etiqueta" => "&#91;23&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Low temperature synthesis&#44; structural and dosimetric characterization of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58;Ce<span class="elsevierStyleSup">3&#43;</span> nanophosphor"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Spectrochim&#46; Acta Part A"
                        "fecha" => "2014"
                        "volumen" => "122"
                        "paginaInicial" => "489"
                        "paginaFinal" => "498"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            23 => array:3 [
              "identificador" => "bib0560"
              "etiqueta" => "&#91;24&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Sr- and Ni-doping in ZnO nanorods synthesized by a simple wet chemical method as excellent materials for CO and CO<span class="elsevierStyleInf">2</span> gas sensing"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "RSC Adv&#46;"
                        "fecha" => "2016"
                        "volumen" => "6"
                        "paginaInicial" => "82733"
                        "paginaFinal" => "82742"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            24 => array:3 [
              "identificador" => "bib0565"
              "etiqueta" => "&#91;25&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Synthesis of Ni-doped ZnO nanostructures by low temperature wet chemical method and their enhanced field emission properties"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "RSC Adv&#46;"
                        "fecha" => "2016"
                        "volumen" => "6"
                        "paginaInicial" => "104318"
                        "paginaFinal" => "104324"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            25 => array:3 [
              "identificador" => "bib0570"
              "etiqueta" => "&#91;26&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:1 [
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:4 [
                        "tituloSerie" => "Acta Crystallogr&#46;&#44; Sect&#46; A&#58; Cryst&#46; Phys&#46;&#44; Diffr&#46; Theor&#46; Gen&#46; Cryst&#46;"
                        "fecha" => "1976"
                        "volumen" => "32"
                        "paginaInicial" => "751"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            26 => array:3 [
              "identificador" => "bib0575"
              "etiqueta" => "&#91;27&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "X-ray line broadening from filed aluminium and wolfram"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Acta Metall&#46;"
                        "fecha" => "1953"
                        "volumen" => "1"
                        "paginaInicial" => "22"
                        "paginaFinal" => "31"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            27 => array:3 [
              "identificador" => "bib0580"
              "etiqueta" => "&#91;28&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Williamson&#8211;Hall analysis in estimation of lattice strain in nanometer-sized ZnO particles"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Theor&#46; Appl&#46; Phys&#46;"
                        "fecha" => "2012"
                        "volumen" => "6"
                        "paginaInicial" => "6"
                        "paginaFinal" => "13"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            28 => array:3 [
              "identificador" => "bib0585"
              "etiqueta" => "&#91;29&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "X-ray Diffraction Crystallography"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Libro" => array:3 [
                        "fecha" => "2011"
                        "paginaInicial" => "75"
                        "editorial" => "Springer-Verlag Berlin Heidelberg"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            29 => array:3 [
              "identificador" => "bib0590"
              "etiqueta" => "&#91;30&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "The evidence for a miscibility gap in the Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span>&#8211;ZnFe<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> system &#8211; a review"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Mater&#46; Trans&#46; B"
                        "fecha" => "1988"
                        "volumen" => "19"
                        "paginaInicial" => "919"
                        "paginaFinal" => "925"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            30 => array:3 [
              "identificador" => "bib0595"
              "etiqueta" => "&#91;31&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Systematics of the spinel structure type"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Phys&#46; Chem&#46; Miner&#46;"
                        "fecha" => "1979"
                        "volumen" => "4"
                        "paginaInicial" => "317"
                        "paginaFinal" => "339"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            31 => array:3 [
              "identificador" => "bib0600"
              "etiqueta" => "&#91;32&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "In-situ high-pressure X-ray diffraction study of zinc ferrite nanoparticles"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Solid State Sci&#46;"
                        "fecha" => "2016"
                        "volumen" => "56"
                        "paginaInicial" => "68"
                        "paginaFinal" => "72"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            32 => array:3 [
              "identificador" => "bib0605"
              "etiqueta" => "&#91;33&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Biomineralization associated with microbial reduction of Fe<span class="elsevierStyleSup">3&#43;</span> and oxidation of Fe<span class="elsevierStyleSup">2&#43;</span> in solid minerals"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Am&#46; Mineral&#46;"
                        "fecha" => "2009"
                        "volumen" => "94"
                        "paginaInicial" => "1049"
                        "paginaFinal" => "1058"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            33 => array:3 [
              "identificador" => "bib0610"
              "etiqueta" => "&#91;34&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Vivianite and siderite in lateritic iron crust&#58; an example of bioreduction"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Quim&#46; Nova"
                        "fecha" => "2007"
                        "volumen" => "30"
                        "paginaInicial" => "36"
                        "paginaFinal" => "40"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            34 => array:3 [
              "identificador" => "bib0615"
              "etiqueta" => "&#91;35&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Zn&#8211;O tetrahedral bond length variations in normal spinel oxides"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Am&#46; Miner&#46;"
                        "fecha" => "2011"
                        "volumen" => "96"
                        "paginaInicial" => "594"
                        "paginaFinal" => "598"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            35 => array:3 [
              "identificador" => "bib0620"
              "etiqueta" => "&#91;36&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Charge order at magnetite Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span>&#40;0<span class="elsevierStyleHsp" style=""></span>0<span class="elsevierStyleHsp" style=""></span>1&#41;&#58; surface and Verwey phase transitions"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1088/0953-8984/27/1/012001"
                      "Revista" => array:6 [
                        "tituloSerie" => "J&#46; Phys&#46; Condens&#46; Matter"
                        "fecha" => "2015"
                        "volumen" => "27"
                        "paginaInicial" => "012001"
                        "paginaFinal" => "012008"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            36 => array:3 [
              "identificador" => "bib0625"
              "etiqueta" => "&#91;37&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "ImageJ User Guide"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Libro" => array:1 [
                        "fecha" => "2012"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            37 => array:3 [
              "identificador" => "bib0630"
              "etiqueta" => "&#91;38&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Correlations between crystallite&#47;particle size and photoluminescence properties of submicrometer phosphors"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Chem&#46; Mater&#46;"
                        "fecha" => "2007"
                        "volumen" => "19"
                        "paginaInicial" => "1723"
                        "paginaFinal" => "1730"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            38 => array:3 [
              "identificador" => "bib0635"
              "etiqueta" => "&#91;39&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Correlation between particle size&#47;domain structure and magnetic properties of highly crystalline Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span> nanoparticles"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1038/s41598-017-09897-5"
                      "Revista" => array:6 [
                        "tituloSerie" => "Sci&#46; Rep&#46;"
                        "fecha" => "2017"
                        "volumen" => "7"
                        "paginaInicial" => "9894"
                        "paginaFinal" => "98911"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            39 => array:3 [
              "identificador" => "bib0640"
              "etiqueta" => "&#91;40&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Structural characterization of Gd<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span> phosphor synthesized by solid state reaction and combustion method using X-ray diffraction and transmission electron microscopic techniques"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Display Technol&#46;"
                        "fecha" => "2016"
                        "volumen" => "12"
                        "paginaInicial" => "921"
                        "paginaFinal" => "927"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            40 => array:3 [
              "identificador" => "bib0645"
              "etiqueta" => "&#91;41&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Mechanical Alloying and Milling"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Libro" => array:4 [
                        "fecha" => "2014"
                        "paginaInicial" => "333"
                        "editorial" => "Marcel Dekker"
                        "editorialLocalizacion" => "NY"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            41 => array:3 [
              "identificador" => "bib0650"
              "etiqueta" => "&#91;42&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Chemical imaging analysis"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "LibroEditado" => array:5 [
                        "paginaInicial" => "269"
                        "paginaFinal" => "313"
                        "serieVolumen" => "vol&#46; 69"
                        "serieTitulo" => "Comprehensive Analytical Chemistry"
                        "serieFecha" => "2015"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            42 => array:3 [
              "identificador" => "bib0655"
              "etiqueta" => "&#91;43&#93;"
              "referencia" => array:1 [
                0 => array:1 [
                  "referenciaCompleta" => "Royal Society of Chemistry&#44; X-ray photoelectron spectroscopy&#44; <a target="_blank" href="https://www.rsc.org/publishing/journals/prospect/ontology.asp?id=CMO:0000404%26MSID=B602486F">https&#58;&#47;&#47;www&#46;rsc&#46;org&#47;publishing&#47;journals&#47;prospect&#47;ontology&#46;asp&#63;id&#61;CMO&#58;0000404&#38;MSID&#61;B602486F</a> &#40;May 2019&#41;&#46;"
                ]
              ]
            ]
            43 => array:3 [
              "identificador" => "bib0660"
              "etiqueta" => "&#91;44&#93;"
              "referencia" => array:1 [
                0 => array:1 [
                  "referenciaCompleta" => "Operator&#39;s PHI MULTIPAK Software Manual&#44; Version 8&#46;2C&#44; Ulvac-PHI&#44; Inc&#46;&#44; Chigasaki City&#44; Kanagawa Prefecture&#44; Japan&#44; 2007&#46;"
                ]
              ]
            ]
            44 => array:3 [
              "identificador" => "bib0665"
              "etiqueta" => "&#91;45&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Luminescence characterization and electron beam induced chemical changes on the surface of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58;Mn nanocrystalline phosphor"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Appl&#46; Surf&#46; Sci&#46;"
                        "fecha" => "2011"
                        "volumen" => "257"
                        "paginaInicial" => "3298"
                        "paginaFinal" => "3306"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            45 => array:3 [
              "identificador" => "bib0670"
              "etiqueta" => "&#91;46&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "A photochemical proposal for the preparation of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and MgAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> thin films from beta-diketonate complex precursors"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Mater&#46; Res&#46; Bull&#46;"
                        "fecha" => "2016"
                        "volumen" => "77"
                        "paginaInicial" => "212"
                        "paginaFinal" => "220"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            46 => array:3 [
              "identificador" => "bib0675"
              "etiqueta" => "&#91;47&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Enhanced green emission from UV down-converting Ce<span class="elsevierStyleSup">3&#43;</span>&#8211;Tb<span class="elsevierStyleSup">3&#43;</span> co-activated ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> phosphor"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Vac&#46; Sci&#46; Technol&#46; B"
                        "fecha" => "2012"
                        "volumen" => "30"
                        "paginaInicial" => "031401"
                        "paginaFinal" => "031407"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            47 => array:3 [
              "identificador" => "bib0680"
              "etiqueta" => "&#91;48&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Low-symmetry mesoporous titanium dioxide &#40;lsm-TiO<span class="elsevierStyleInf">2</span>&#41; electrocatalyst for efficient and durable oxygen evolution in aqueous alkali"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Electrochem&#46; Soc&#46;"
                        "fecha" => "2018"
                        "volumen" => "165"
                        "paginaInicial" => "H300"
                        "paginaFinal" => "H309"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            48 => array:3 [
              "identificador" => "bib0685"
              "etiqueta" => "&#91;49&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Luminescent properties and X-ray photoelectron spectroscopy study of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58;Ce<span class="elsevierStyleSup">3&#43;</span>&#44;Tb<span class="elsevierStyleSup">3&#43;</span> phosphor"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Alloys Compd&#46;"
                        "fecha" => "2011"
                        "volumen" => "509"
                        "paginaInicial" => "10115"
                        "paginaFinal" => "10120"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            49 => array:3 [
              "identificador" => "bib0690"
              "etiqueta" => "&#91;50&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "ESCA studies of yttrium aluminum garnets"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Phys&#46; Chem&#46; B"
                        "fecha" => "1999"
                        "volumen" => "103"
                        "paginaInicial" => "1454"
                        "paginaFinal" => "1461"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            50 => array:3 [
              "identificador" => "bib0695"
              "etiqueta" => "&#91;51&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "The influence of process parameters and pulse ratio of precursors on the characteristics of La<span class="elsevierStyleInf">1&#8722;<span class="elsevierStyleItalic">x</span></span>Al<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span>O<span class="elsevierStyleInf">3</span> films deposited by atomic layer deposition"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1186/s11671-015-0883-6"
                      "Revista" => array:6 [
                        "tituloSerie" => "Nanoscale Res&#46; Lett&#46;"
                        "fecha" => "2015"
                        "volumen" => "10"
                        "paginaInicial" => "180"
                        "paginaFinal" => "189"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            51 => array:3 [
              "identificador" => "bib0700"
              "etiqueta" => "&#91;52&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Enhanced ammonia dehydrogenation over Ru&#47;La&#40;<span class="elsevierStyleItalic">x</span>&#41;&#8211;Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span> &#40;<span class="elsevierStyleItalic">x</span><span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>0&#8211;50<span class="elsevierStyleHsp" style=""></span>mol&#37;&#41;&#58; structural and electronic effects of La doping"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Int&#46; J&#46; Hydrogen Energy"
                        "fecha" => "2017"
                        "volumen" => "42"
                        "paginaInicial" => "1639"
                        "paginaFinal" => "1647"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            52 => array:3 [
              "identificador" => "bib0705"
              "etiqueta" => "&#91;53&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "The support effects on the direct conversion of syngas to higher alcohol synthesis over copper-based catalysts"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Catalysts"
                        "fecha" => "2019"
                        "volumen" => "9"
                        "paginaInicial" => "199"
                        "paginaFinal" => "2016"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            53 => array:3 [
              "identificador" => "bib0710"
              "etiqueta" => "&#91;54&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Plasma-assisted hot filament chemical vapor deposition of AlN thin films on ZnO buffer layer&#58; toward highly c-axis-oriented&#44; uniform&#44; insulative films"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Appl&#46; Phys&#46; A"
                        "fecha" => "2014"
                        "volumen" => "117"
                        "paginaInicial" => "2217"
                        "paginaFinal" => "2224"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            54 => array:3 [
              "identificador" => "bib0715"
              "etiqueta" => "&#91;55&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Novel polyelectrolyte&#8211;Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span>&#47;SiO<span class="elsevierStyleInf">2</span> composite nanoabrasives for improved chemical mechanical polishing &#40;CMP&#41; of sapphire"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Mater&#46; Res&#46;"
                        "fecha" => "2019"
                        "volumen" => "34"
                        "paginaInicial" => "1073"
                        "paginaFinal" => "1082"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            55 => array:3 [
              "identificador" => "bib0720"
              "etiqueta" => "&#91;56&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Inorganic Nanostructures"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Libro" => array:4 [
                        "fecha" => "2012"
                        "paginaInicial" => "41"
                        "editorial" => "Wiley-VCH Verlag &#38; Co&#46; KGaA"
                        "editorialLocalizacion" => "Weinheim&#44; Germany"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            56 => array:3 [
              "identificador" => "bib0725"
              "etiqueta" => "&#91;57&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Influence of annealing environment on the ALD-Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span>&#47;4H&#8211;SiC interface"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Phys&#46; D&#58; Appl&#46; Phys&#46;"
                        "fecha" => "2018"
                        "volumen" => "51"
                        "paginaInicial" => "105111"
                        "paginaFinal" => "105127"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            57 => array:3 [
              "identificador" => "bib0730"
              "etiqueta" => "&#91;58&#93;"
              "referencia" => array:1 [
                0 => array:1 [
                  "referenciaCompleta" => "T&#46; Helmenstine&#44; List of electronegativity values of the elements&#44; <a target="_blank" href="https://sciencenotes.org/list-of-electronegativity-values-of-the-elements/">https&#58;&#47;&#47;sciencenotes&#46;org&#47;list-of-electronegativity-values-of-the-elements&#47;</a> &#40;June 2019&#41;&#46;"
                ]
              ]
            ]
            58 => array:3 [
              "identificador" => "bib0735"
              "etiqueta" => "&#91;59&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Influence of inversion defects and Cr&#8211;Cr pairs on the photoluminescent performance of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> crystals"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Sol&#8211;Gel Sci&#46; Technol&#46;"
                        "fecha" => "2018"
                        "volumen" => "85"
                        "paginaInicial" => "121"
                        "paginaFinal" => "131"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            59 => array:3 [
              "identificador" => "bib0740"
              "etiqueta" => "&#91;60&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Surface smoothing and native oxide suppression on Zn doped aerotaxy GaAs nanowires"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Appl&#46; Phys&#46;"
                        "fecha" => "2019"
                        "volumen" => "125"
                        "paginaInicial" => "025303"
                        "paginaFinal" => "0253011"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            60 => array:3 [
              "identificador" => "bib0745"
              "etiqueta" => "&#91;61&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Localized nano-solid-solution induced by Cu doping in ZnS for efficient solar hydrogen generation"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1039/c4dt00969j"
                      "Revista" => array:6 [
                        "tituloSerie" => "Dalton Trans&#46;"
                        "fecha" => "2014"
                        "volumen" => "43"
                        "paginaInicial" => "11533"
                        "paginaFinal" => "11541"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            61 => array:3 [
              "identificador" => "bib0750"
              "etiqueta" => "&#91;62&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Relationship between ferromagnetism and formation of complex carbon bonds in carbon doped ZnO powders"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1039/c9cp01277j"
                      "Revista" => array:6 [
                        "tituloSerie" => "Phys&#46; Chem&#46; Chem&#46; Phys&#46;"
                        "fecha" => "2019"
                        "volumen" => "21"
                        "paginaInicial" => "8808"
                        "paginaFinal" => "8819"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            62 => array:3 [
              "identificador" => "bib0755"
              "etiqueta" => "&#91;63&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Improvement of structural and optical properties of ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58;Cr<span class="elsevierStyleSup">3&#43;</span> ceramics with surface modification by using various concentrations of zinc acetate"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Sol&#8211;Gel Sci&#46; Technol&#46;"
                        "fecha" => "2018"
                        "volumen" => "88"
                        "paginaInicial" => "422"
                        "paginaFinal" => "429"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            63 => array:3 [
              "identificador" => "bib0760"
              "etiqueta" => "&#91;64&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Structural&#44; elemental&#44; optical and magnetic study of Fe doped ZnO and impurity phase formation"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Proc&#46; Nat&#46; Sci&#46; Mater&#46;"
                        "fecha" => "2014"
                        "volumen" => "24"
                        "paginaInicial" => "142"
                        "paginaFinal" => "149"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            64 => array:3 [
              "identificador" => "bib0765"
              "etiqueta" => "&#91;65&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Tuning the surface anisotropy in Fe-doped NiO nanoparticles"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Nanoscale"
                        "fecha" => "2014"
                        "volumen" => "6"
                        "paginaInicial" => "352"
                        "paginaFinal" => "357"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            65 => array:3 [
              "identificador" => "bib0770"
              "etiqueta" => "&#91;66&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Analysis of XPS spectra of Fe<span class="elsevierStyleSup">2&#43;</span> and Fe<span class="elsevierStyleSup">3&#43;</span> ions in oxide materials"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Appl&#46; Surf&#46; Sci&#46;"
                        "fecha" => "2008"
                        "volumen" => "254"
                        "paginaInicial" => "2441"
                        "paginaFinal" => "2449"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            66 => array:3 [
              "identificador" => "bib0775"
              "etiqueta" => "&#91;67&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Electrodeposition and characterization of ZnX &#40;X<span class="elsevierStyleHsp" style=""></span>&#61;<span class="elsevierStyleHsp" style=""></span>Se&#44; Te&#41; semiconductor thin films"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:4 [
                        "tituloSerie" => "Bol&#46; Soc&#46; Chil&#46; Qu&#237;m&#46;"
                        "fecha" => "2002"
                        "volumen" => "47"
                        "paginaInicial" => "411"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            67 => array:3 [
              "identificador" => "bib0780"
              "etiqueta" => "&#91;68&#93;"
              "referencia" => array:1 [
                0 => array:1 [
                  "host" => array:1 [
                    0 => array:1 [
                      "LibroEditado" => array:3 [
                        "editores" => "J&#46;Tauc"
                        "titulo" => "The Optical Properties of Solids"
                        "serieFecha" => "1966"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            68 => array:3 [
              "identificador" => "bib0785"
              "etiqueta" => "&#91;69&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Electronic structure of spinel oxides&#58; zinc aluminate and zinc gallate"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Phys&#46; Condens&#46; Matter"
                        "fecha" => "1999"
                        "volumen" => "11"
                        "paginaInicial" => "3635"
                        "paginaFinal" => "3644"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            69 => array:3 [
              "identificador" => "bib0790"
              "etiqueta" => "&#91;70&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Full-potential calculations of structural&#44; elastic and electronic properties of MgAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> and ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> compounds"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Phys&#46; Lett&#46; A"
                        "fecha" => "2005"
                        "volumen" => "344"
                        "paginaInicial" => "271"
                        "paginaFinal" => "279"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            70 => array:3 [
              "identificador" => "bib0795"
              "etiqueta" => "&#91;71&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Synthesis and characterization studies of ZnFe<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> nanoparticles"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "MMSE"
                        "fecha" => "2017"
                        "volumen" => "9"
                        "paginaInicial" => "13"
                        "paginaFinal" => "17"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            71 => array:3 [
              "identificador" => "bib0800"
              "etiqueta" => "&#91;72&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Photodegradation of rhodamine B by using ZnFe<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> nanoparticles synthesized through precipitation method"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:4 [
                        "tituloSerie" => "IOP Conf&#46; Ser&#46; Mater&#46; Sci&#46; Eng&#46;"
                        "fecha" => "2017"
                        "volumen" => "202"
                        "paginaInicial" => "012044"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            72 => array:3 [
              "identificador" => "bib0805"
              "etiqueta" => "&#91;73&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Reflectance Spectroscopy"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Libro" => array:5 [
                        "fecha" => "1969"
                        "paginaInicial" => "103"
                        "paginaFinal" => "169"
                        "editorial" => "Springer-Verlag"
                        "editorialLocalizacion" => "New York"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            73 => array:3 [
              "identificador" => "bib0810"
              "etiqueta" => "&#91;74&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Tight-binding theory of heterojunction band lineups and interface dipoles"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Vac&#46; Sci&#46; Technol&#46; B"
                        "fecha" => "1986"
                        "volumen" => "4"
                        "paginaInicial" => "1068"
                        "paginaFinal" => "1073"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            74 => array:3 [
              "identificador" => "bib0815"
              "etiqueta" => "&#91;75&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Intense photoluminescence of slightly doped ZnO&#8211;SiO<span class="elsevierStyleInf">2</span> matrix"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Chem&#46; Phys&#46; Lett&#46;"
                        "fecha" => "2006"
                        "volumen" => "425"
                        "paginaInicial" => "77"
                        "paginaFinal" => "81"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            75 => array:3 [
              "identificador" => "bib0820"
              "etiqueta" => "&#91;76&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Single-source sol&#8211;gel synthesis of nanocrystalline ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span>&#58; structural and optical properties"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Am&#46; Ceram&#46; Soc&#46;"
                        "fecha" => "2001"
                        "volumen" => "84"
                        "paginaInicial" => "1921"
                        "paginaFinal" => "1928"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            76 => array:3 [
              "identificador" => "bib0825"
              "etiqueta" => "&#91;77&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "The role of surface Zn<span class="elsevierStyleSup">2&#43;</span> ions in the transesterification of vegetable oils over ZnO supported on Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span> and Fe<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span>"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Catal&#46; Sci&#46; Technol&#46;"
                        "fecha" => "2014"
                        "volumen" => "4"
                        "paginaInicial" => "851"
                        "paginaFinal" => "860"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            77 => array:3 [
              "identificador" => "bib0830"
              "etiqueta" => "&#91;78&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Formation of complete solid solutions&#44; Zn&#40;Al<span class="elsevierStyleInf"><span class="elsevierStyleItalic">x</span></span>Ga<span class="elsevierStyleInf">1&#8722;<span class="elsevierStyleItalic">x</span></span>&#41;<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> spinel nanocrystals via hydrothermal route"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Ceram&#46; Int&#46;"
                        "fecha" => "2014"
                        "volumen" => "40"
                        "paginaInicial" => "15841"
                        "paginaFinal" => "15848"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            78 => array:3 [
              "identificador" => "bib0835"
              "etiqueta" => "&#91;79&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Effect of heat-treatment and composition on structure and luminescence properties of spinel-type solid solution nanocrystals"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1166/jnn.2015.10272"
                      "Revista" => array:6 [
                        "tituloSerie" => "J&#46; Nanosci&#46; Nanotechnol&#46;"
                        "fecha" => "2015"
                        "volumen" => "15"
                        "paginaInicial" => "6069"
                        "paginaFinal" => "6077"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            79 => array:3 [
              "identificador" => "bib0840"
              "etiqueta" => "&#91;80&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "ZnAl<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">4</span> as a potential sensor&#58; variation of luminescence with thermal history"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Mater&#46; Chem&#46; C"
                        "fecha" => "2013"
                        "volumen" => "1"
                        "paginaInicial" => "5419"
                        "paginaFinal" => "5428"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            80 => array:3 [
              "identificador" => "bib0845"
              "etiqueta" => "&#91;81&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Photoluminescence and photoacoustic spectroscopies of Fe<span class="elsevierStyleSup">3&#43;</span> in the LiGa<span class="elsevierStyleInf">5</span>O<span class="elsevierStyleInf">8</span>&#8211;LiGaSiO<span class="elsevierStyleInf">4</span>&#8211;Li<span class="elsevierStyleInf">5</span>GaSi<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">8</span> system"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1007/s10895-008-0404-4"
                      "Revista" => array:6 [
                        "tituloSerie" => "J&#46; Fluoresc&#46;"
                        "fecha" => "2009"
                        "volumen" => "19"
                        "paginaInicial" => "211"
                        "paginaFinal" => "219"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            81 => array:3 [
              "identificador" => "bib0850"
              "etiqueta" => "&#91;82&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Synthesis and luminescence characteristics of Dy<span class="elsevierStyleSup">3&#43;</span> doped KLa&#40;PO<span class="elsevierStyleInf">3</span>&#41;<span class="elsevierStyleInf">4</span>"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Lumin&#46;"
                        "fecha" => "2015"
                        "volumen" => "166"
                        "paginaInicial" => "82"
                        "paginaFinal" => "87"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            82 => array:3 [
              "identificador" => "bib0855"
              "etiqueta" => "&#91;83&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Emerging ultra-narrow-band cyan-emitting phosphor for white LEDs with enhanced color rendition"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:2 [
                      "doi" => "10.1038/s41377-019-0148-8"
                      "Revista" => array:6 [
                        "tituloSerie" => "Light-Sci&#46; Appl&#46;"
                        "fecha" => "2019"
                        "volumen" => "8"
                        "paginaInicial" => "38"
                        "paginaFinal" => "47"
                        "link" => array:1 [ …1]
                      ]
                    ]
                  ]
                ]
              ]
            ]
            83 => array:3 [
              "identificador" => "bib0860"
              "etiqueta" => "&#91;84&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Transition metal-doped chalcogenide glasses for broadband near-infrared sources"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "LibroEditado" => array:5 [
                        "paginaInicial" => "289"
                        "paginaFinal" => "296"
                        "serieVolumen" => "vol&#46; 5620"
                        "serieTitulo" => "Solid State Laser Technologies and Femtosecond Phenomena"
                        "serieFecha" => "2004"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            84 => array:3 [
              "identificador" => "bib0865"
              "etiqueta" => "&#91;85&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Interpretation of the changing the band gap of Al<span class="elsevierStyleInf">2</span>O<span class="elsevierStyleInf">3</span> depending on its crystalline form&#58; connection with different local symmetries"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "J&#46; Phys&#46; Chem&#46; C"
                        "fecha" => "2015"
                        "volumen" => "119"
                        "paginaInicial" => "20755"
                        "paginaFinal" => "20761"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            85 => array:3 [
              "identificador" => "bib0870"
              "etiqueta" => "&#91;86&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Charge-transfer transitions and pseudoacceptor states of iron in gallium phosphide"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [
                        "tituloSerie" => "Phys&#46; Rev&#46; B"
                        "fecha" => "1993"
                        "volumen" => "47"
                        "paginaInicial" => "16267"
                        "paginaFinal" => "16273"
                      ]
                    ]
                  ]
                ]
              ]
            ]
            86 => array:3 [
              "identificador" => "bib0875"
              "etiqueta" => "&#91;87&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Photoluminescence and photothermal effect of Fe<span class="elsevierStyleInf">3</span>O<span class="elsevierStyleInf">4</span> nanoparticles for medical imaging and therapy"
                      "autores" => array:1 [
                        0 => array:2 [ …2]
                      ]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "Revista" => array:5 [ …5]
                    ]
                  ]
                ]
              ]
            ]
            87 => array:3 [
              "identificador" => "bib0880"
              "etiqueta" => "&#91;88&#93;"
              "referencia" => array:1 [
                0 => array:2 [
                  "contribucion" => array:1 [
                    0 => array:2 [
                      "titulo" => "Nanoscale analyses applied to nanowire devices"
                      "autores" => array:1 [ …1]
                    ]
                  ]
                  "host" => array:1 [
                    0 => array:1 [
                      "LibroEditado" => array:5 [ …5]
                    ]
                  ]
                ]
              ]
            ]
          ]
        ]
      ]
    ]
    "agradecimientos" => array:1 [
      0 => array:4 [
        "identificador" => "xack535380"
        "titulo" => "Acknowledgements"
        "texto" => "<p id="par0240" class="elsevierStylePara elsevierViewall">The authors express their sincere thanks to the South African Research Chairs Initiative of the Department of Science and Technology and the National Research Foundation of South Africa &#40;84415&#41;&#46; The financial assistance from the <span class="elsevierStyleGrantSponsor" id="gs1">University of the Free State&#44; South Africa</span> is highly recognized&#46;</p>"
        "vista" => "all"
      ]
    ]
  ]
  "idiomaDefecto" => "en"
  "url" => "/03663175/0000006000000003/v2_202106110717/S0366317520300297/v2_202106110717/en/main.assets"
  "Apartado" => null
  "PDF" => "https://static.elsevier.es/multimedia/03663175/0000006000000003/v2_202106110717/S0366317520300297/v2_202106110717/en/main.pdf?idApp=UINPBA00004N&text.app=https://www.elsevier.es/"
  "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S0366317520300297?idApp=UINPBA00004N"
]

Article information

ISSN: 03663175
Original language: English

DOI:10.1016/j.bsecv.2020.02.005

The statistics are updated each day

Year/Month	Html	Pdf	Total

2024 November	11	1	12
2024 October	74	12	86
2024 September	80	4	84
2024 August	87	1	88
2024 July	167	8	175
2024 June	76	12	88
2024 May	83	24	107
2024 April	94	28	122
2024 March	145	29	174
2024 February	138	41	179
2024 January	179	32	211
2023 December	174	46	220
2023 November	179	35	214
2023 October	207	42	249
2023 September	191	19	210
2023 August	107	10	117
2023 July	141	17	158
2023 June	122	16	138
2023 May	134	27	161
2023 April	161	16	177
2023 March	132	23	155
2023 February	102	20	122
2023 January	84	21	105
2022 December	82	30	112
2022 November	103	32	135
2022 October	70	35	105
2022 September	68	32	100
2022 August	89	50	139
2022 July	85	42	127
2022 June	127	33	160
2022 May	147	37	184
2022 April	224	48	272
2022 March	370	41	411
2022 February	400	59	459
2022 January	273	61	334
2021 December	177	44	221
2021 November	253	26	279
2021 October	129	38	167
2021 September	102	34	136
2021 August	129	46	175
2021 July	83	36	119
2021 June	66	28	94
2021 May	44	17	61
2021 April	76	81	157
2021 March	37	37	74
2021 February	40	29	69
2021 January	51	18	69
2020 December	55	11	66
2020 November	47	18	65
2020 October	18	8	26
2020 September	38	13	51
2020 August	19	10	29
2020 July	28	28	56
2020 June	17	18	35
2020 May	32	22	54
2020 April	0	2	2

Show all

Indexed in:

Follow us:

Statistics

Indexed in:

Follow us:

Statistics

Subscribe to our newsletter