Recent Progress on Carbon Nitride and Its Hybrid Photocatalysts for CO 2 Reduction

Graphitic carbon nitride as a novel photocatalyst for CO 2 reduction reaction (CO 2 RR) has attracted many recent efforts on the synthesis and modification for improving efficiency and selectivity. Herein, an overview of fundamental factors and the latest research progress of g‐C 3 N 4 ‐based photocatalysts for CO 2 RR is provided. The main strategies of fabrication and modification to obtain g‐C 3 N 4 and g‐C 3 N 4 ‐based composites with high CO 2 RR efficiency are summarized. Working mechanisms of each enhancement approach in terms of their effects on electronic band structures, light‐harvesting capability, CO 2 adsorption capacity, separation of photogenerated electron–hole pairs etc. are explained and discussed. Finally, a brief overview on the challenges and new directions in this field is proposed.