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 unfavourable for the CO2 adsorption and hinder the efficient carrier separation on the surface of MHP NCs, leading to inferior catalytic activity in artificial photosynthesis. Herein, we construct CsPbBr3 nanocrystals with short-chain glycine as ligand based on a facile ligand-exchange strategy. Owing to the reduced hindrance of glycine and the presence of amine group in glycine, the photogenerated carrier separation and CO2 uptake capacity can be noticeably improved without compromising stability of MHP NCs. CsPbBr3 nanocrystals with glycine ligands exhibit 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 5 times higher than that of control CsPbBr3 NCs with conventional long alkyl-chain capping ligands.