Luminescence properties of nanostructured alumina ceramic

Photo- and cathodoluminescence spectra of the nanostructured Al2O3 ceramic and anion-defective alpha-Al2O3 crystals are studied under comparable conditions. Luminescence bands of the centers produced by oxygen vacancies are detected in samples of both types. The nanostructured ceramic is characterized by a new band at 3.4 eV and the reduction of the luminescence decay time. The specific features of the luminescence of the nanostructured ceramic can be related to the presence of nonequilibrium phases and specificity of relaxation processes. (C) 2007 Elsevier Ltd. All rights reserved.