Artigo
Visible PL phenomenon at room temperature in disordered structure of SrWO4 powder
Fecha
2005-01-01Registro en:
Journal of Computer-aided Materials Design. Dordrecht: Springer, v. 12, n. 2-3, p. 111-119, 2005.
0928-1045
10.1007/s10820-006-9002-4
WOS:000240432700004
Autor
Universidade Estadual Paulista (Unesp)
Universidade Federal de São Carlos (UFSCar)
Univ Limoges
Universidade Federal da Paraíba (UFPB)
Resumen
The SrWO4 (SWO) powders were synthesized by the polymeric precursor method and annealed at different temperatures. The SWO structure was obtained by X-ray diffraction and the corresponding photoluminescence (PL) spectra was measured. The PL results reveal that the structural order-disorder degree in the SWO lattice influences in the PL emission intensity. Only the structurally order-disordered samples present broad and intense PL band in the visible range. To understand the origin of this phenomenon, we performed quantum-mechanical calculations with crystalline and order-disordered SWO periodic models. Their electronic structures were analyzed in terms of band structure. The appearance of localized levels in the band gap of the order-disordered structure was evidenced and is a favorable condition for the intense PL to occur.