Preparation of High Activity TiO2/g-C3N4 Photocatalysts via a Facile Sol-gel Method with Ti(OBu)4 as Ti Source and Melamine as Nitrogen Source

A highly active photocatalyst TiO2/g-C3N4 was synthesized by a facile two-step method including sol-gel and calcination, using Ti(OBu)4 as a Ti source and melamine as a nitrogen source. The resultant photocatalysts were characterized by XRD, TEM and UV-vis diffuse reflectance spectra. The results show that TiO2/g-C3N4 is formed and TiO2 is beset with graphite-like carbon nitride of layer structure. TiO2/g-C3N4 exhibits obviously enhanced visible light photocatalytic activity, and the degradation efficiency of Methylene blue (MB) reaches 94.46% after irradiation for 1 h, which is much higher than that of g-C3N4 and TiO2. The improved photocatalytic activity of TiO2/g-C3N4 is attributable to its wide spectrum responsive range, strong visible light adsorption capability, and the synergistic effect between TiO2 and g-C3N4. The mechanism of photocatalytic reaction was discussed.