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

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 (CO 2 ) 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 CO 2 reduction photosystems by an electrostatic self-assembly strategy, which is enabled by precisely anchoring CsPbBr 3 quantum dots (QDs) on the 2D TMC (CdIn 2 S 4, ZnIn 2 S 4, In 2 S 3 ) 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 CO 2 photoreduction, thus endowing the self-assembled TMCs/CsPbBr 3 nanocomposites with considerably improved visible-light-driven photocatalytic performances toward CO 2 reduction to carbon monoxide with high selectivity. The enhanced photocatalytic performances of TMCs/CsPbBr 3 heterostructures are attributed to the abundant active sites on the TMC frameworks, excellent light absorption of CsPbBr 3 QDs, and well-defined 2D/0D heterostructures of TMCs/CsPbBr 3 QDs photosystems, which synergistically boosts the directional charge transport from CsPbBr 3 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.