Otro
Study of the annealing temperature effect on the structural and luminescent properties of SrWO4:Eu phosphors prepared by a non-hydrolytic sol-gel process
Registro en:
Journal of Alloys and Compounds. Lausanne: Elsevier B.V. Sa, v. 526, p. 11-21, 2012.
0925-8388
10.1016/j.jallcom.2012.02.083
WOS:000302770400003
Autor
Pereira, P. F. S.
de Moura, A. P.
Nogueira, I. C.
Lima, M. V. S.
Longo, Elson
de Sousa Filho, P. C.
Serra, O. A.
Nassar, E. J.
Rosa, I. L. V.
Resumen
In this paper, we investigate the influence of temperature on the structural and luminescent properties of Eu3+-doped strontium tungstate oxide (SrWO4) prepared by the non-hydrolytic sol-gel route. X-ray diffraction (XRD) analyses showed that the SrWO4:Eu scheelite type structure was formed in a unique phase at 900 and 1000 degrees C over 2 h. Raman spectra indicated only one type of [WO4] tetrahedron. The optical properties were investigated by ultraviolet-visible (UV-vis) absorption spectroscopy and photoluminescence (PL) measurements at room and liquid N-2 temperatures. PL study showed D-5(0)-> F-7(2) electric dipole transition is dominant when Eu3+ occupies a non-centrosymmetric environment. The (FEG-SEM) images indicated that an increase in the annealing temperature contributed to the coalescence process which promoted the growth of aggregated particles of a polydisperse nature. A qualitative analysis of the powders obtained by dispersive X-ray detector (EDS) indicated that the samples are composed of Sr, W and O while Eu3+ ion was not observed due to it low concentration. (C) 2012 Elsevier B. V. All rights reserved. Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)