Promoting Photocatalytic H2 Evolution through Retarded Charge Trapping and Recombination by Continuously Distributed Defects in Methylammonium Lead Iodide Perovskite

Abstract Inspired by its great success in the photovoltaic field, methylammonium lead iodide perovskite (MAPbI 3 ) has recently been actively explored as photocatalysts in H 2 evolution reactions. However, the practical application of MAPbI 3 photocatalysts remains hampered by the intrinsically fast trapping and recombination of photogenerated charges. Herein, we propose a novel strategy of regulating the distribution of defective areas to promote charge‐transfer dynamics of MAPbI 3 photocatalysts. By deliberately designing and synthesizing the MAPbI 3 photocatalysts featuring a unique continuation of defective areas, we demonstrate that such a feature enables retardation of charge trapping and recombination via lengthening the charge‐transfer distance. As an outcome, such MAPbI 3 photocatalysts turn out to achieve an impressive photocatalytic H 2 evolution rate as high as 0.64 mmol ⋅ g −1 ⋅ h −1 , one order of magnitude higher than that of the conventional MAPbI 3 photocatalysts. This work establishes a new paradigm for controlling charge‐transfer dynamics in photocatalysis.