Room-Temperature Persistent Luminescence in Metal Halide Perovskite Nanocrystals for Solar-Driven CO₂ Bioreduction

The rapid crystal growth of metal halide perovskite (MHP) nanocrystals inevitably leads to the generation of abundant crystal defects in the lattice. Here, defects-mediated long-lived charges and accompanying room-temperature persistent luminescence are demonstrated to be a general phenomenon in MHP nanocrystals. Density functional theory calculations suggest that the collaboration of Schottky and point defects enables upward cascading depletion for electron transfer in MHP nanocrystals, leading to the generation of long-lived photoexcited charges with lifetimes over 30 min. The excellent optical properties including the presence of long-lived charges, high charge separation efficiency, and broad absorption in the visible region make MHPs ideal candidates for both photocatalysis and photo-biocatalysis. The MHPs were further integrated with enzymes to construct a light-driven biosynthetic system for the selective production of fine chemicals from CO₂ with solar energy. The biosynthetic system can produce formate with a quantum yield of 3.24%, much higher than that of plants (∼0.2–1.6%). These findings will benefit the understanding of the optoelectronic properties of MHPs and further provide opportunities for the development of biosynthetic systems for solar-to-chemical synthesis. © 2022 Chinese Chemical Society.