Microstructure and photocatalytic activity of TiO2-SiO2 composite materials

Abstract

Abstract TiO2-SiO2 composite materials with different composition (from 0 to 50 mol % SiO2) were prepared by sol-gel method. Microstructure, optical property and photocatalytic activity of TiO2-SiO2 composite materials were characterized by Raman scattering, ultraviolet-visible (UV-vis) spectrometer and photocatalytic degradation of methylene blue. The Raman spectra results showed that TiO2-SiO2 composite materials contained only a single crystalline phase of anatase TiO2. It also indicated the inclusion of SiO2 suppressed the growth of anatase TiO2. The UV-vis absorption spectra showed that the absorption edge of TiO2-SiO2 composite materials has a blue shift as the SiO2 increased. The optical band gap of TiO2-SiO2 increased from 3.06 eV to 3.32 eV for TiO2 and 0.5TiO2-0.5SiO2. The adsorption performance and photocatalytic activity of TiO2-SiO2 was enhanced with the increase of SiO2 content. 0.5TiO2-0.5SiO2 has the best absorption performance and photocatalytic activity in our experiment. And it has potential application value in the field of photocatalytic materials.