Ultrathin 2D/2D ZnInS/LaTiO nanosheets with a Z-scheme heterojunction for enhanced photocatalytic hydrogen evolution.

Layered lanthanum titanate (LaTiO) perovskite is a good photocatalytic material owing to its high stability, strong redox ability, and non-toxicity. However, its inherent wide bandgap limits its application in photocatalytic hydrogen evolution. Therefore, combining LaTiO with two-dimensional (2D) narrow-bandgap semiconductors to form 2D/2D layered structures is the preferred strategy to improve its photocatalytic performance. In this study, a novel 2D/2D ZnInS/LaTiO Z-scheme heterojunction was prepared through a solvothermal method. The experimental results show that when the molar ratio of LaTiO to ZnInS is 1 : 4, the hydrogen evolution rate of the composite under ultraviolet-visible light reaches 6.97 mmol g h, which is 3.5 times higher than that of the pure ZnInS. The results of the morphological characterization studies of the samples and the photoelectrochemical measurements show that channels for the rapid transfer of carriers are generated by the unique 2D/2D structure of these samples, and the separation and migration efficiency of the photogenerated carriers significantly improved due to the formation of the Z-scheme heterojunction. This study provides useful insights into the modulation of wide-bandgap semiconductors and research into solar energy conversion.