Efficient Photocatalytic CO₂ Reduction by the Construction of Ti₃C₂/CsPbBr₃ QD Composites

Photoreduction of CO2 into useable hydrocarbon fuels has been widely used in the energy conversion field. However, the high carrier recombination rate and the low conversion efficiency of as-prepared catalysts greatly restrict their photocatalytic application. Herein, we synthesize Ti3C2/CsPbBr3 quantum dot (Ti3C2/CsPbBr3 QD) composites by the method of self-assembly, which are used in the photoreduction of CO2. As a result, Ti3C2/CsPbBr3 QD composites exhibit excellent photocatalytic activity and stability for the photocatalytic CO2 reduction. Especially, the generation rate of CO (17.98 μmol h–1 g–1) for Ti3C2/CsPbBr3 QD composites is 9.37 times higher than that of CsPbBr3 QDs (1.92 μmol h–1 g–1), and 97.35% of the activity is still retained after three consecutive cycles. The improved photocatalytic performance is mainly attributed to the construction of the type II-2 heterojunction as the built internal electric field (IEF) in the p–n junction could accelerate the separation for both photoinduced holes and electrons. Therefore, this work provides an insight into the construction of heterojunction photocatalysts with halide perovskite QD materials for photocatalytic applications.