The sol-gel synthesis and photocatalytic activity of Gd-SiO2-TiO2 photocatalyst

The sol-gel method was used to synthesize Gd-SiO 2 -TiO 2 composite photocatalysts. When the doping amounts of Si and Gd reached 9.1 mol% and 0.2 mol% respectively, the sample showed the optimal photocatalytic activity during the methylene blue (MB) degradation. When the calcination temperature was lower than 550 °C, Gd-SiO 2 -TiO 2 photocatalyst has an anatase crystal structure. After doping of Si and Gd, the absorption wavelength thresholds of the sample approached 407 nm with the energy gap of 3.05 eV. Gd-SiO 2 -TiO 2 photocatalyst showed the degradation efficiency about 90% to methylene blue (MB) under irradiation of simulated sunlight.