Structural and luminescence characteristics of SnO2:Eu and SnO2:Eu,Sb nanophosphors upon annealing at high temperatures

The paper explores the structure and luminescence of sol-gel-derived SnO2:Eu and SnO2:Eu,Sb nanopowders which may be useful as electrically conductive phosphors. The samples were sintered in air at temperatures reaching up to 1400 degrees C. Raman-, SEM-, EDX- and photoluminescence characterization of the samples was carried out. High-temperature annealing of SnO2:Eu leads to a nanoparticulate phosphor with considerable efficiency of host-sensitized Eu3+ emission under UV excitation although the emission is slightly quenched at room temperature. While Sb co-dopant immensely improves crystallization at 1400 degrees C, it also impairs luminescence performance. SEM and EDX characterization suggest pronounced segregation of Eu induced by the enhanced crystal growth. Interestingly, Sb-doping seems to activate in the Raman spectrum quite a few SnO2 vibrations which are normally rather weak or IR active. (C) 2011 Elsevier B.V. All rights reserved.