Heterostructures based on g-C₃N₄ for the photocatalytic CO₂ reduction

The interest of the global scientific community in the problems of CO₂ utilization and returning to the carbon cycle has markedly increased in recent years. Among various CO₂ transformation processes, photocatalytic reduction is one of the most promising. Currently, much attention is paid to photocatalysts based on graphitic carbon nitride, since the use of g-C₃N₄ makes it possible to perform CO₂ reduction under visible or solar light irradiation. To increase the reduction efficiency, g-C₃N₄ is subjected to various modifications with the most popular and promising approach being the synthesis of composite photocatalysts based on g-C₃N₄ with other semiconductors to form heterostructures. Depending on the type of semiconductor, transfer of photogenerated charge carriers in these systems can occur by various mechanisms, which largely determine the course of the process and the rates of formation of reaction products. This review addresses studies on the synthesis of composite photocatalysts based on g-C₃N₄, with emphasis being placed on the mechanisms of charge carrier transfer and the distribution of products of CO₂ reduction. The bibliography includes 235 references.