The 3D/2D g-C 3N 4/ZnIn 2S 4 hollow spherical heterostructure can greatly increase visible light absorption and improve the efficiency of photo-generated electron migration and conversion, resulting in an excellent CO generation rate.
A 3D/2D g-C 3N 4/ZnIn 2S 4 hollow spherical heterostructure was constructed by growing modified ZnIn 2S 4 nanosheets on the surface of g-C 3N 4 microspheres. This composite material can not only take advantage of the hollow structure with a stronger light absorption capacity and more active sites, but its heterostructure can also increase the efficiency of photogenerated electron migration and separation, thereby improving the serious photogenerated electron recombination of two separate materials. The unique structural superiority led to excellent photocatalytic CO 2 reduction performance, where a higher CO generation rate reaching 7368.7 μmol g −1 h −1 by using IZIS–CN100 was undoubtedly strong evidence. The heterojunction formation process and the subsequent electronic changes on both theoretical and experimental aspects of the combination of electrochemical tests and density functional theory (DFT) were verified. Finally, we proposed a feasible photocatalytic mechanism and brought forth new ideas in the application of materials, structural control, and the combination of theories and experiments.