Preparation,Characterization and Visible Light Photocatalytic Activity of N-doped TiO_2

Nitrogen-doped TiO2 photocatalyst is prepared by a simple hydrolysis method using tetrabutyl titanate as titanium source and urea as nitrogen source,followed by calcination at 450 ℃.The obtained catalysts exhibit photocatalytic activity in simulated sunlight due to N doping.The light absorption edge of N-doped TiO2 is shifted to the visible light region compared to pure TiO2 characterized by UV-Vis absorption spectroscopy.N-doped TiO2 powders are characterized to be anatase by XRD;its crystallite size is about 12.8 nm,and the specific surface area is 70.8 m2/g.The result of element analysis reveals N content of N-doped TiO2 is 0.32%,and N atoms assigned to Ti-N bond in TiO2 crystal lattice.The photocatalytic activity of samples is evaluated by the degradation rate of methylene blue under Xe lamp irradiation.The results indicate that N-doped TiO2 exhibits higher visible light activity;the highest degradation rate of methylene blue is 93.7%.