Intense blue and green photoluminescence emissions at room temperature in barium zirconate powders


Autoria(s): Cavalcante, L. S.; Sczancoski, J. C.; Espinosa, J. W. M.; Mastelaro, V. R.; Michalowicz, A.; Pizani, P. S.; Vicente, Fábio Simões de; Li, M. S.; Varela, José Arana; Longo, Elson
Contribuinte(s)

Universidade Estadual Paulista (UNESP)

Data(s)

30/09/2013

20/05/2014

30/09/2013

20/05/2014

05/03/2009

Resumo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Intense blue and green photoluminescence (PL) emissions were observed at room temperature in barium zirconate (BaZrO(3)) powders prepared by chemical method. The powders were analyzed by X-ray diffraction (XRD), X-ray absorption near edge spectroscopy (XANES), extended X-ray absorption spectroscopy (EXAFS) and ultraviolet-visible (UV-vis) absorption spectroscopy. The XRD patterns indicated the presence of a secondary phase of BaCO(3) in BaZrO(3) powders heat treated at 773K. K-edge XANES data revealed that Zr atoms presents in at least two Zr environments. EXAFS investigations showed strong bond length dispersion in the first coordination shell around Zr atoms. EXAFS analysis indicated that Zr atoms are coordinated by 6 oxygen in BaZrO(3) powders heat treated at 973 K. UV-vis measurements suggested the presence of intermediary energy levels into the band gap of BaZrO(3) powders heat treated at 773K. The intense PL emission in BaZrO(3) powders can be attributed to the two Zr environments or ZrO(5)-ZrO(6) clusters. (C) 2008 Elsevier B.V. All rights reserved.

Formato

253-258

Identificador

http://dx.doi.org/10.1016/j.jallcom.2008.03.080

Journal of Alloys and Compounds. Lausanne: Elsevier B.V. Sa, v. 471, n. 1-2, p. 253-258, 2009.

0925-8388

http://hdl.handle.net/11449/25014

10.1016/j.jallcom.2008.03.080

WOS:000265086300063

Idioma(s)

eng

Publicador

Elsevier B.V. Sa

Relação

Journal of Alloys and Compounds

Direitos

closedAccess

Palavras-Chave #Disordered systems #Clusters #Chemical synthesis #Order-disorder effects #EXAFS
Tipo

info:eu-repo/semantics/article