Preparation and application of g-C₃N₄-based photocatalyst

Graphitic carbon nitride (g-C₃N₄), one kind of semiconductor materials with advantages like no toxicity, small band gap (2.7 eV) and strong absorption capacity for visible light in solar spectrum, is a new type of photocatalyst which has gained rapid development in recent years. Pure g-C₃N₄, however, has such disadvantages as limited ability to capture visible light, easy recombination with charge carriers and low specific surface area. Its photocatalytic efficiency is hard to meet large-scale application in industry. In this paper, different synthesis methods of g-C₃N₄ were summarized. The strategies for further enhancing the activity of g-C₃N₄ were described, including the control of pore and specific surface area, noble metal deposition, nonmetal doping, and formation of the composite material by semiconductor coupling. The research progress of the application of g-C₃N₄-based photocatalyst in the degradation of organic pollutants, photocatalytic water splitting and reduction of hexavalent chromium was analyzed. Finally, the new prospect for the research on g-C₃N₄-based photocatalyst was proposed.