Structure, Surface Properties and Photocatalytic Activity of TiO_2 Nanoparticles

TiO2 nanoparticles were prepared by the hydrolysis of titanium alkoxide. The prop- erties of the particles were characterized by XRD, SPS, XPS and ESR techniques. The particle size of the TiO2 increased as the calcining temperature increased and the structure of the TiO2 changed from anatase to rutile. The photocatalytic oxidation of heptane was used as model reac- tion to measure the photocatalytic activity of TiO2 particles. The photocatalytic activity of TiO2 particles washed with ethanol is higher than that of TiO2 particles washed with water. The 1ower calcining temperature induces the blue-shift of photovoltage, the threshold higher, and the content of Ti3+ higher, which help to enhance the photocatalytic activity of TiO2 particles.