Abstract
Nanocrystalline GdAlO3-delta powders were prepared by means of solid state-reaction process. The parent compound GdAlO3 (delta=0.0) has a broad electronic band gap of 5.0 eV and do not present photoluminescence (PL) emission. This work aims to study the effect of the introduction of oxygen deficiencies in the GdAlO3-delta compounds on the establishing of PL signal. XRD patterns revealed that all samples present an orthorhombic structure with the absence of structural transition when increasing delta.
The optical study exposed a very intense green PL emission, observed at room temperature and centered at 530 nm using a 350 nm excitation line. The PL emission was related to the oxygen deficiencies doubly ionized vacancy Vo(center dot center dot), created in the orthorhombic structure of GdAlO3-delta compounds, which may be responsible for the formation of intermediary energy levels into the band gap. (C) 2014 Elsevier B.V. All rights reserved.