Construction of WO3/CsPbBr3 S-scheme heterojunction via electrostatic Self-assembly for efficient and Long-Period photocatalytic CO2 reduction

Owing to the severe photogenerated carriers recombination and low oxidation ability, the photocatalytic performance of pristine CsPbBr3 is still unsatisfactory. Herein, melamine foam supported S-scheme WO3/CsPbBr3 heterojunction is successfully synthesized by electrostatic self-assembly. Because of the appropriate energy level positions, an S-scheme charge migration route between CsPbBr3 and WO3 is constructed. Under solar light irradiation, melamine foam assisted WO3/CsPbBr3 exhibits significantly enhanced photocatalytic CO2 reduction performance under liquid H2O medium, and the electron consumption rate (Relectron) reaches to 1225.50 μmol.g-1.h-1, which is 1.49- and 13.7-fold of CsPbBr3 and WO3, respectively, ascribing to the boosted charges transfer and the strengthened redox ability. Furthermore, S-scheme WO3/CsPbBr3 heterojunction also exhibits strong durability, with no noticeable reduction of product yields after four 8-h cycles.