Enhancing photocatalytic CO2 reduction by fabricating intimate contact interfacial of SnIn4S8/Co3O4 2D-2D heterojunction photocatalyst

The utilization of heterojunction photocatalysts in photocatalytic CO 2 conversion has attracted significant attention. Nevertheless, the interface structure between the two components in the heterojunction material essentially decides the carrier separation efficiency and the performance of photocatalytic CO 2 reduction. The development of semiconductor heterojunctions with suitable materials and intimate interfacial contact is paramount. In this study, SnIn 4 S 8 /Co 3 O 4 heterostructures have been successfully fabricated by a facile hydrothermal synthesis method. The experimental results demonstrated that the established internal electric field effectively suppressed the recombination of photogenerated carriers and accelerated charge transfer kinetics. Meanwhile, the increased specific surface area endows SnIn 4 S 8 /Co 3 O 4 heterostructures with an improved CO 2 adsorption ability, ultimately achieving a significant improvement in photocatalytic activity. The highest formation rate of CO and CH 4 reaches 38.20 and 3.60 μmol g −1  h −1 . The design strategy reveals the potential of establishing intimate interfacial contacts as an extremely efficient catalyst for photocatalytic CO 2 reduction, facilitating effective charge separation. This work provides distinctive thoughts for the development of advanced catalytic material design for CO 2 conversion and other photocatalytic applications.