“…A great number of photocatalysts, for example, metal oxides, metal sulfide, organic polymers, metal organic frameworks, and covalent organic frameworks, have been developed to catalyze the conversion of CO 2 to hydrocarbon fuels. [15][16][17][18] Organic polymer carbon nitride (g-CN) is attracting increasing attention since Wang et al found its application in photocatalysis hydrogen evolution. 19,20 In the past few years, g-CN has been widely studied in the field of photocatalysis CO 2 reduction due to its suitable band gap for visible light absorption, strong redox ability, low costs, and ecofriendly properties.…”