Vacancy-mediated regulation of an S-scheme CsPbBr3/VC-CN heterojunction to boosting charge transfer for efficient CO2 photocatalytic reduction

Designing S-scheme heterojunctions with high charge separation efficiency and strong photo-redox capability is regarded as effective way to enhance the photocatalytic activity, yet achieving S-scheme charge transfer remains challenging. In this work, we report the construction of a well-designed S-scheme heterojunction by integrating carbon vacancies-containing carbon nitride (V C -CN) and CsPbBr 3 quantum dots. Experimental studies and density functional theory (DFT) calculations demonstrate that the enlarged interfacial interaction induced by the V C within CN could achieve a directional S-scheme charge transfer, therefore improving photogenerated carrier separation capability and consequently promoting photocatalytic CO 2 reduction performance. The CO evolution rate over 5 % CsPbBr 3 /V C -CN S-scheme heterojunction is 84.39 μmol·g −1 ·h −1 , which is 16.26 times than that of CN. Our work offers an alternative strategy to construct S-scheme heterojunction photocatalytic for CO 2 reduction via modulating the internal electric filed achieved by defect engineering route.