3D ZnO hollow spheres-dispersed CsPbBr3 quantum dots S-scheme heterojunctions for high-efficient CO2 photoreduction

Abstract

Efficient electron transfer process and excellent CO2 adsorption capacity are of great significance for improving CO2 photoreduction efficiency. 3D-0D ZnO/CsPbBr3 S-scheme heterojunction hollow spheres were successfully prepared via a simple self-assembled process for efficient CO2 photoreduction. Photocatalytic CO2 reduction experiments showed that the ZnO/CsPbBr3 had the excellent CO2 photocatalytic conversion activity to CO, which was about 2.61 times higher than that of ZnO hollow micro-spheres and 1.9 times higher than that of pure CsPbBr3 quantum dots (QDs). Photoelectrochemical characterization confirmed that the ZnO/CsPbBr3 composite had good photoelectric conversion ability and carrier transfer ability, which was beneficial to the photocatalytic reaction. The suitable band gap structure and DFT calculation results showed that the formation of built-in electric field at the ZnO/CsPbBr3 interface can greatly improve the S-scheme electron transfer ability, which can foster the CO2 photoreduction. Besides, the introduction of 3D structure can improve the dispersion of CsPbBr3 QDs and effectively enhance the CO2 capture ability of the catalyst, which greatly promoted the CO2 photoreduction reaction. The current work can present a novel S-scheme photocatalyst, which is looked forward to providing a certain perception into the advance of novel highly efficient CsPbBr3 QDs-based photocatalysts for CO2 resource utilization.