Blue Photoluminescence of Sol–Gel TiO2–SiO2Glass

Abstract

nTiO2–(100–n)SiO2 glasses (n =0.5, 1, 2, 3 and 5 wt %) were prepared by the sol–gel method. The photoluminescence (PL) properties of the glasses heat-treated at different temperatures were studied for the first time. A blue emission band centered at 445 nm was observed in all the samples. Their PL intensity strongly depends on the heat-treatment temperatures and the different TiO2 content. The PL intensity of all the samples is much stronger than that of pure SiO2 glass. The PL could be attributed to the luminescent centers associated with the defects in the sol–gel TiO2–SiO2 glass network. The heat-treatment and TiO2 content have an effect on the defect concentration and on the network completion and thus influence the emission.