Incorporation of Cesium Lead Halide Perovskites into g-C₃N₄ for Photocatalytic CO₂ Reduction

Abstract

CsPbBr₃ perovskite-based composites so far have been synthesized by postdeposition of CsPbBr₃ on a parent material. However, <i>in situ</i> construction offers enhanced surface contact, better activity, and improved stability. Instead of applying a typical thermal condensation at highly elevated temperatures, we report for the first time CsPb(Br _<i>x</i> Cl_1-<i>x</i> )₃/graphitic-C₃N₄ (CsPbX₃/g-C₃N₄) composites synthesized by a simple and mild solvothermal route, with enhanced efficacy in visible-light-driven photocatalytic CO₂ reduction. The composite exhibited a CO production rate of 28.5 μmol g^-1 h^-1 at an optimized loading amount of g-C₃N₄. This rate is about five times those of pure g-C₃N₄ and CsPbBr₃. This work reports a new <i>in situ</i> approach for constructing perovskite-based heterostructure photocatalysts with enhanced light-harvesting ability and improved solar energy conversion efficiency.