2D Covalent Organic Frameworks as Photocatalysts for Solar Energy Utilization

In the context of the energy crisis and global warming, developing clean and sustainable energy is receiving increasing attention. Photocatalytic processes including water splitting, CO₂ reduction, coenzyme regeneration, etc., provide ideal ways to utilize renewable solar resources. The photocatalyst plays a central role in photocatalytic processes. Organic porous polymers have recently gained extensive attention in photocatalysis. Covalent organic frameworks (COFs), as one of the organic porous polymers, have the characteristics of high crystallinity, porosity, and structural designability that make them perfect platforms for photocatalysis. In this minireview, the recent progress of 2D COFs as photocatalysts is summarized including the recent work. The synthesis of the diversified structures of the COFs including the different linkages is first introduced. Then, the photocatalytic applications of the 2D COFs including photocatalytic hydrogen evolution, CO₂ conversion, coenzyme regeneration, and other traditional organic reaction are then discussed. Finally, conclusions and prospects are provided in the last section.