Photocatalytic degradation of phenol in aqueous nitrogen-doped TiO_2 suspensions with various light sources

摘要

In this study,the nitrogen-doped TiO_2 polycrystalline powders were synthesized by calcination of the hydrolysis product of tetra-butyl titanate with ammonia.According to the XRD,SEM,XPS,UV-vis absorption and BET analysis,we found that the N-doped TiO_2 has mesoporous structures and the nitrogen doping causes the absorption edge of TiO_2 to shift to a lower energy region.It is considered that nitrogen atoms in doped TiO_2 polycrystalline powder are responsible for the significant enhancement in the doped TiO_2 photoactivity under visible light irradiation.We explored the photocatalytic activity of N-doped TiO_2 under various irradiation conditions.We found the photocatalytic activity of the N-doped TiO_2 with anatase phases was higher than that of the commercial TiO_2 photocatalyst Degussa P25 for phenol decomposition under visible light irradiation,while Degussa P25 showed higher photocatalytic activity under sunlight irradiation.The FT-IR spectra showed that products of phenol decomposition adsorbed on the catalyst surface after photodegradation of phenol.