Steering Photocatalytic CO₂ Conversion over CsPbBr₃ Perovskite Nanocrystals by Coupling with Transition-Metal...

Transition-metal chalcogenides (TMCs) have received enormous attention by virtue of their large light absorption coefficient, abundant catalytically active sites, and markedly reduced spatially vectorial charge-transfer distance originating from generic structural merits. However, the controllable construction of TMC-based heterostructured photosystems for photocatalytic carbon dioxide (CO₂) reduction is retarded by the ultrashort charge lifetime, sluggish charge-transfer kinetics, and low target product selectivity. Herein, we present the rational design of two-dimensional (2D)/zero-dimensional (0D) heterostructured CO₂ reduction photosystems by an electrostatic self-assembly strategy, which is enabled by precisely anchoring CsPbBr₃ quantum dots (QDs) on the 2D TMC (CdIn₂S₄, ZnIn₂S₄, In₂S₃) frameworks. The peculiar 2D/0D integration mode and suitable energy-level alignment between these two assembly units afford maximal interfacial contact and applicable potential for CO₂ photoreduction, thus endowing the self-assembled TMCs/CsPbBr₃ nanocomposites with considerably improved visible-light-driven photocatalytic performances toward CO₂ reduction to carbon monoxide with high selectivity. The enhanced photocatalytic performances of TMCs/CsPbBr₃ heterostructures are attributed to the abundant active sites on the TMC frameworks, excellent light absorption of CsPbBr₃ QDs, and well-defined 2D/0D heterostructures of TMCs/CsPbBr₃ QDs photosystems, which synergistically boosts the directional charge transport from CsPbBr₃ QDs to TMCs, enhancing the interfacial charge migration/separation. Our work would inspire the construction of novel TMCs-involved photosystems for solar-to-fuel conversion.