Optimal Architecture of a Dual S-Scheme ZnIn(2)S(4)–ZnO–Al(2)O(3) Heterosystem with High H(2) Evolution Rate under Visible Light

[Image: see text] In this study, dual S-scheme ZnIn(2)S(4)–Al(2)O(3)–ZnO (ZIS–Al–Zn) heterojunctions were produced by a facile, low cost, and rapid combustion technique. These heterojunctions accelerated the photocatalytic hydrogen production due to the multi-channel-promoted separation of photocarriers. By optimizing the content of the components, the synthesized ZIS–Al–Zn composite with 20 wt% of ZnIn(2)S(4) and 30 wt% of Al(2)O(3) in the ZIS–Al–Zn composite demonstrated the highest hydrogen production rate of 54.2 mmol g(–1) h(–1), which was nearly 11 and 8.30 times better than ZnO–Al(2)O(3) and ZnO–ZnIn(2)S(4) composites, respectively. The results of DRS, PL, EIS, LSV, and CV techniques showed the highest shift in the light absorption, rapid interfacial transfer, and quenched recombination of photocarriers over the ternary ZIS–Al–Zn composite than single and binary catalysts. The obtained results revealed the formation of a dual S-scheme mechanism of transfer of photocarriers in ZIS–Al–Zn heterojunctions, contributing to better hydrogen production efficiency. The optimized ZIS–Al–Zn composite also exhibited good stability and reusability.