MoS₂ Assisted Two-Dimensional Perovskite of (PEA)₂(MA)_<i>n</i>−1Pb_<i>n</i>I_3<i>n</i>+1 (<i>n</i> = 1, 2, 3, 4) for Photocatalytic Hydrogen

Although lead halide perovskites have proven to be potential photocatalysts for hydrogen halide splitting and evolution, the preparation of efficient and stable catalysts remains challenging. Two-dimensional perovskites of (PEA)2PbnI3n+1 (n = 1, 2, 3, and 4) were used for photocatalytic hydrogen production, among which (PEA)2(MA)Pb2I7 presented an optimal hydrogen content as high as 0.26 mmol·h–1·g–1. To further improve the photocatalytic performance, MoS2 nanocrystals with abundant active sites were assembled with (PEA)2(MA)n−1PbnI3n+1 microcrystals to form new heterostructures. With the benefit of MoS2, the (PEA)2(MA)Pb2I7/MoS2 mixture yielded 1.69 mmol·h–1·g–1 hydrogen. The introduction of suitable MoS2 and unsaturated components can effectively improve the charge separation effect and provide more active sites for hydrogen production. The photocatalytic hydrogen evolution of two-dimensional perovskites provides a highly efficient and stable perovskite-based catalyst.