Fabrication and photoluminescence of monolithic silica glass doped with alumina nanoparticles using SiO₂-PVA nanocomposite

Al₂O₃ nanoparticle doped SiO₂-PVA nanocomposites were prepared using fumed silica, fumed alumina, and poly(vinyl alcohol) (PVA). Nanocomposites containing from 0 to 6 mol% Al₂O₃ were heat-treated in air at 1100 to 1300°C to obtain monolithic, transparent silica glass. The 0.6 mol% Al₂O₃ doped nanocomposite was sintered at 1200°C, a higher temperature than was required for the non-doped nanocomposite. The obtained Al₂O₃ doped silica glass exhibited characteristic blue photoluminescence (PL) on UV excitation. The effects of the Al₂O₃ nanoparticles on the sintering temperature and the PL characteristics of the sintered silica glass are discussed in terms of the morphology and structure of the sintered glass.