Autor segons l'article: Slimi S; Loiko P; Volokitina A; Bogdanov K; Solé RM; Aguiló M; Díaz F; Salem EB; Mateos X
Departament: Química Física i Inorgànica
Autor/s de la URV: Mateos Ferré, Xavier / Solé Cartañà, Rosa Maria / Volokitina, Anna
Paraules clau: Thermal stability Phosphor Luminescence High color purity Europium ions Doping mechanism Crystal structure Apatite up-conversion thermal-stability thermal stability spectroscopic properties quantum efficiency photoluminescence properties phosphor micro-raman luminescence properties luminescence high-brightness europium ions energy-transfer doping mechanism crystal structure
Resum: Eu3+-doped and undoped Ca8NaBi(PO4)6F2:xEu (x = 0.01–0.5) apatite phosphors have been synthesized at 900 °C by the modified Pechini process. Their structural and morphological characteristics were determined by XRD, TEM and Raman spectroscopy. The structure of the host matrix was refined by the Rietveld method: Ca8NaBi(PO4)6F2 crystallizes in hexagonal class, sp. gr. P63/m, a = b = 9.3980 (6) Å, c = 6.9039 (9) Å and γ = 120°). The electronic structure was simulated revealing an indirect bandgap of 3.46 eV Eu3+ ions in the host matrix replace for the Bi3+ ones in two types of sites: M1 (C3 symmetry and IX-fold oxygen coordination) and M2 (CS symmetry and VII-fold coordination by one fluoride and six oxygens). The doping induces a redistribution of Eu3+ ions over the M1 and M2 sites in favor of the former species. The transition probabilities for Eu3+ ions in M2 sites were determined using the Judd-Ofelt theory yielding a radiative lifetime of 2.21 ms. It was found that phosphors exhibit relatively weak luminescence quenching. The CIE 1931 color coordinates for the compound with x = 0.35 Eu are (0.648,0.352) falling in the red region and corresponding to a correlated color temperature of 2919 K and a color purity of >96%. The thermal stability of the phosphor was studied until 400 °C (the determined activation energy is 0.70 eV) indicating a redistribution of ions in favor of the M2 sites at high temperatures. Ca8NaBi(PO4)6F2:xEu apatites are promising as red phosphors for white-light LEDs.
Àrees temàtiques: Química Optics Odontología Medicina ii Medicina i Materiais Interdisciplinar General chemistry Farmacia Ensino Engenharias iv Engenharias iii Engenharias ii Condensed matter physics Ciências biológicas ii Ciências biológicas i Ciências ambientais Ciência de alimentos Chemistry (miscellaneous) Chemistry (all) Biotecnología Biophysics Biochemistry Atomic and molecular physics, and optics Astronomia / física
Accès a la llicència d'ús: https://creativecommons.org/licenses/by/3.0/es/
Adreça de correu electrònic de l'autor: xavier.mateos@urv.cat rosam.sole@urv.cat anna.volokitina@estudiants.urv.cat
Identificador de l'autor: 0000-0003-1940-1990 0000-0002-5769-4141 0000-0002-6091-6534
Data d'alta del registre: 2023-02-23
Versió de l'article dipositat: info:eu-repo/semantics/publishedVersion
Enllaç font original: https://www.sciencedirect.com/science/article/pii/S0022231321006396
URL Document de llicència: http://repositori.urv.cat/ca/proteccio-de-dades/
Referència a l'article segons font original: Journal Of Luminescence. 241
Referència de l'ítem segons les normes APA: Slimi S; Loiko P; Volokitina A; Bogdanov K; Solé RM; Aguiló M; Díaz F; Salem EB; Mateos X (2022). Structure, optical properties and preferential site substitution of Eu3+ activated Ca8NaBi(PO4)6F2 red emitting phosphors prepared by modified Pechini process. Journal Of Luminescence, 241(), -. DOI: 10.1016/j.jlumin.2021.118523
DOI de l'article: 10.1016/j.jlumin.2021.118523
Entitat: Universitat Rovira i Virgili
Any de publicació de la revista: 2022
Tipus de publicació: Journal Publications
Repositori URV