Fabrication and Visible Light Photocatalytic Activity of N-S Co-Doped Nano TiO2

N-S co-doped nano TiO2 photocatalysts were fabricated by a modified sol-gel method using tetrabutyl titanate as the Ti source, urea and thiourea as the dopants. The photocatalysts were characterized by XRD, TEM, XPS, and UV-vis diffuse reflectance spectroscopy (DRS). It is found that N-S co-doped TiO2 photocatalysts, prepared at 450 degrees C in air, are complete anatase phase and the mean size of the particles is about 14 nm. Compared with the pure TiO2 prepared with the same condition, the N-S co-doped TiO2 photocatalysts exhibit an evident redshift in the band edge and an obvious increase in visible region absorption. The tests of photocatalytic degradation of weak acid red under visible light irradiation show that the co-doping with nitrogen and sulfur can enhance photocatalytic activities of the photocatalysts.