Modulating Band Structure and Charge-Carrier Dynamics in MoS 2 /ZnIn 2 S 4 Heterojunction Composites for High-Efficiency Photocatalytic H 2 Production

The high demand for fossil fuels in human activities and industrial production has intensified environmental pollution, global warming, and energy shortages, making the development of alternative energy and energy-storage technologies imperative. Among these approaches, photocatalytic conversion of solar energy into hydrogen is regarded as a sustainable solution to the energy and environmental crises. However, the rapid recombination of photogenerated charge carriers and the lack of effective active sites severely limit photocatalytic performance. To address these challenges, heterojunction engineering is often employed to suppress electron-hole recombination and enhance photocatalytic H 2 evolution efficiency. A MoS 2 /ZnIn 2 S 4 heterojunction was constructed via the in situ growth of MoS 2 nanorods on the surface of ZnIn 2 S 4 . The introduction of MoS 2 not only broadens the light-absorption range of ZnIn 2 S 4 , but also suppresses the recombination of photogenerated charge carriers, thereby significantly enhancing the photocatalytic H 2 evolution performance of ZnIn 2 S 4 . The optimal MoS 2 loading was 30 wt%, at which the photocatalytic H 2 evolution rate reached 11.52 mmol·g −1 ·h −1 , nearly 2.5 times that of pure MoS 2 . In addition, the catalyst maintained nearly unchanged activity after five consecutive cycles, indicating good stability and that photocorrosion was effectively suppressed in the presence of sacrificial reagents. The heterojunction formed between MoS 2 and ZnIn 2 S 4 shortens the charge-transfer pathway and improves the separation efficiency of photogenerated electrons and holes, thereby suppressing charge-carrier recombination and accelerating the photocatalytic H 2 evolution re photocorrosion action.