Temperature and TiO 2 content effects on the photoluminescence properties of Eu 3 + doped TiO 2 - SiO 2 powders

Eu 3 + doped TiO 2 - SiO 2 powders were produced by the sol-gel method. The TiO 2 content was changed from low to high content ( 20 - 100 mol % ) annealing at 900 ° C for 1 h, and the 2 mol % Eu 3 + doped 60 % TiO 2 - 40 % SiO 2 powders were annealed at different temperatures ( 600 - 1000 ° C ) . The structure of the samples was investigated by high resolution transmission electron microscopy, x-ray diffraction, and Raman technique. The photoluminescence (PL) spectra and PL excitation spectra were recorded at room temperature. The results showed that the PL intensity was dependent on the annealing temperatures and TiO 2 content, which could be attributed to the cluster formation.