Tunable Photocatalytic Two-Electron Shuttle between Paired Redox Sites on Halide Perovskite Nanocrystals

Perovskite semiconductors as advanced solar energy-converting materials are promising catalysts for photoredox organic synthesis. Despite the high concentration of charge carriers generated on the perovskite surface, efficient utilization of these nonequilibrium and shambolic energetic carriers to trigger a chemical reaction remains a hot and challenging subject. Here, we report a photon-mediated electron shuttle between paired redox sites on perovskite nanocrystals for the reformation of highly stable carbon–halogen bonds, where both surface electrons and holes are utilized simultaneously. The photo-redox cascade can be effortlessly tailored by precise control of the surface-reducing/-oxidizing reaction rates, which unlocks the transformation for a wide range of (het)arenes. This work demonstrates colloidal perovskite photocatalysts for the direct installation of more than 10 different synthetically important functional groups onto arenes and heteroarenes.