Glycine‐Functionalized CsPbBr3 Nanocrystals for Efficient Visible‐Light Photocatalysis of CO2 Reduction

Capping ligands are indispensable for the preparation of metal‐halide‐perovskite (MHP) nanocrystals (NCs) with good stability; however, the long alkyl‐chain capping ligands in conventional MHP NCs will be unfavorable for CO2 adsorption and hinder the efficient carrier separation on the surface of MHP NCs, leading to inferior catalytic activity in artificial photosynthesis. Herein, CsPbBr3 nanocrystals with short‐chain glycine as ligand are constructed through a facile ligand‐exchange strategy. Owing to the reduced hindrance of glycine and the presence of the amine group in glycine, the photogenerated carrier separation and CO2 uptake capacity are noticeably improved without compromising the stability of the MHP NCs. The CsPbBr3 nanocrystals with glycine ligands exhibit a significantly increased yield of 27.7 μmol g−1 h−1 for photocatalytic CO2‐to‐CO conversion without any organic sacrificial reagents, which is over five times higher than that of control CsPbBr3 NCs with conventional long alkyl‐chain capping ligands. Ligand exchange: Glycine‐functionalized CsPbBr3 nanocrystals are constructed through a facile ligand‐exchange strategy. They exhibit a significantly improved yield of 27.7 μmol g−1 h−1 for photocatalytic CO2‐to‐CO conversion coupled with water oxidation, which is over five times higher than that of control CsPbBr3 with conventional long alkyl‐chain capping ligands.