Solar Hydrogen Production by (HA)PbX₄ (X = I, Br) 2D Perovskite Crystals Doped with MoS₂

Halide perovskites have gained significant attention in the field of photovoltaics and photocatalysis due to their exceptional optoelectronic properties. However, the exploration of other classes of 2D perovskite materials is limited. In this work, the photocatalytic performance of (HA)PbX 4 2D crystals embedded with MoS 2 in their bulk structure is investigated. The (HA)PbX 4 @MoS 2 composites are directly synthesized in a (HA)PbX 4 crystal solution. Notably, the (HA)PbI 4 @MoS 2 composite exhibits a remarkable 2.94‐fold increase in H 2 evolution activity. Furthermore, the composite demonstrated stability in a (HA)PbX 4 (HA = histamine, X = I, Br, Cl)‐saturated aqueous HX solution. The photogenerated electrons in (HA)PbX 4 are efficiently transferred to the MoS 2 sites, facilitating the reduction of protons to H 2 . In this study, the potential of hybrid 2D perovskite–MoS 2 composites is highlighted as promising visible‐light photocatalysts for aqueous solution applications.