Photoredox Catalysis by Covalent Organic Frameworks

In recent years, photocatalysis that uses solar energy for either fuel production, such as hydrogen evolution and hydrocarbon production, or directed organic transformations, has shown great potential to achieve the goal of finding clean and renewable energy sources. Covalent organic frameworks (COFs) are crystalline organic porous materials formed by the covalent bonding of organic building blocks, which features superior structural regularity, robust framework, inherent porosity, and diverse functionality. The introduction of organic monomers with adjustable light absorption ability into COFs can make them show strong potential in photocatalysis. This chapter presents the recent progress of COF-based photocatalysts. The use of COF photocatalysts in a myriad of photoredox catalysts with a range of applications, including photocatalytic water splitting, photocatalytic CO2 reduction, photocatalytic organic transformations, and photocatalytic environmental pollutant degradation will be highlighted. Furthermore, various linkers between COF building blocks such as nitrogen-containing connections and all sp2-carbon connections will be summarized and compared. Finally, a perspective on the opportunities and challenges for the future development of COF and COF-based photocatalysts will be given