Light-Driven Hydrogen Generation from Methanol Vapor Using Halide Perovskite Nanocrystals

The facile preparation, structural tunability, and unique optical properties of halide perovskites have led to great success in solar cells and light-emitting devices. However, due to their instability in low-cost polar solvents (e.g., methanol and water), their application in photocatalysis is currently lagging and usually requires special encapsulation. Herein, we demonstrate that halide perovskite (MAPbBr₃, CsPbBr₃) nanocrystals are stable for photocatalytic hydrogen production from methanol/water vapor as proton sources without special protection in the presence of Pt cocatalysts. In methanol vapor, an optimal MAPbBr₃ perovskite NC film exhibits steady hydrogen evolution for ∼20 h under solar irradiation, reaching a marked hydrogen evolution rate of 424 μmol·g^–1·h^–1. Notably, time-resolved spectroscopies reveal that the diffusion-limited feeding of electron–hole pairs toward Pt clusters dominates the dynamics of charge transfer. This study shows the potential of directly using halide perovskites for light-driven reactions in polar environments.