Graphitic carbon nitride heterojunction photocatalysts for solar hydrogen production

Photocatalytic hydrogen production is considered as an ideal approach to solve global energy crisis and environmental pollution. Graphitic carbon nitride (g-C3N4) has received extensive consideration due to its facile synthesis, stable physicochemical properties, and easy functionalization. However, the pristine g-C3N4 usually shows unsatisfactory photocatalytic activity due to the limited separation efficiency of photogenerated charge carriers. Generally, introducing semiconductors or co-catalysts to construct g–C3N4–based heterojunction photocatalysts is recognized as an effective method to solve this bottleneck. In this review, the advantages and characteristics of various types of g–C3N4–based heterojunction are analyzed. Subsequently, the recent progress of highly efficient g–C3N4–based heterojunction photocatalysts in the field of photocatalytic water splitting is emphatically introduced. Finally, a vision of future perspectives and challenges of g–C3N4–based heterojunction photocatalysts in hydrogen production are presented. Predictably, this timely review will provide valuable reference for the design of efficient heterojunctions towards photocatalytic water splitting and other photoredox reactions.