A novel S-scheme ZnO/Ce-g-C₃N₅ heterojunctions with enhanced photocatalytic activity

The g-C₃N₅, characterized by its two-dimensional layered structure, substantial surface area, and narrow bandgap, has found extensive application in photocatalysis. This study involves the incorporation of cerium-doped g-C₃N₅ with ZnO to form a S-scheme photocatalyst, significantly enhancing the photocatalytic activity of the material. The ZnO/Ce-g-C₃N₅ composite photocatalyst shows a degradation efficiency for methylene blue (MB) that is 5.0 times higher than that of g-C₃N₅ and 2.9 times higher than that of ZnO. This superior performance is attributed to the synergistic effect of Ce doping and S-type heterojunction formation, which markedly enhances the separation of photo-induced electron-hole pairs and broadens the light response range, while also maintaining the high redox capacity of the S-scheme ZnO/Ce-g-C₃N₅ system. The fabrication of this novel photocatalyst holds promising prospects for the treatment of organic pollutants in water.