Enhanced photocatalytic degradation performance of a novel ZnS/CdIn2S4 Z-type heterojunction

The development of innovative photocatalysts with high adsorption capacity and efficient charge separation capabilities represents a critical breakthrough in dye wastewater treatment. In this study, an eco-friendly Z-scheme heterojunction ZnS/CdIn2S4 composite photocatalyst was successfully synthesized through an innovative combination of hydrothermal synthesis and ultrasonic dispersion techniques. Experimental results demonstrated that the optimal ZnS/CdIn2S4 composite with a molar ratio of 2:1 achieved 93% degradation efficiency for methylene blue under visible light irradiation within 3 hours. Multidimensional characterization techniques were employed to elucidate the performance enhancement mechanisms: XPS analysis confirmed strong electronic coupling at the heterointerface, while SEM images revealed ZnS nanoparticles uniformly loaded on layered CdIn2S4. This synergistic effect originates from the internal electric field formed at the heterojunction interface, which not only shortens the migration distance of photogenerated electrons (<5 nm) but also promotes spatial charge separation through band bending. This research provides new insights for designing efficient and stable Z-scheme photocatalytic systems, demonstrating significant application potential in the treatment of dye-containing wastewater.