Novel CoS/ZnIn2S4 S-scheme heterojunction for efficient visible-light photocatalytic H2O2 production via dual-channel reactions in air

• • The optimized CoS/ZIS-3 composite achieved a H2O2 production rate of 2693.39 μmol g−1 h−1 under visible light in isopropanol, which is 6.54 times higher than pristine ZIS and 18.08 times higher than CoS, demonstrating a significant performance enhancement for photocatalytic H2O2 synthesis. • • The S-scheme heterojunction and built-in electric field synergistically improved charge carrier separation and transport, addressing the bottleneck of rapid recombination in pristine ZIS and leading to a substantial increase in photocatalytic efficiency. • • The CoS/ZIS composite broadened the light absorption spectrum compared to ZIS, enabling more efficient utilization of visible light, which is critical for solar-driven applications. • • The produced H2O2 exhibited dual functionality: it effectively degraded organic pollutants and inhibited the growth of E. coli, showcasing its potential for environmental remediation and disinfection applications.