Carbon Doping and Oxygen Vacancy-Tungsten Trioxide/Cu3SnS4 S-Scheme Heterojunctions for Boosting Visible-Light-Driven Photocatalytic Performance

Developing ideal photocatalysts for energy regeneration and environmental remediation by combining the advantages of individual semiconductors remains a significant challenge. Herein, tungsten trioxide (WO 3 )/Cu 3 SnS 4 S-scheme heterojunction composite photocatalysts are developed. Initially, doped oxygen vacancy (OV) was prepared on two-dimensional WO 3 nanosheets by direct calcination method. Subsequently, Cu 3 SnS 4 nanoflowers are produced via a one-step hydrothermal process, which are then used to wrap the WO 3 nanosheets. The close contact between WO 3 and Cu 3 SnS 4, coupled with unsaturated C–OV coordination, enhanced the interfacial electron transport. Under visible light irradiation, the WO 3 /Cu 3 SnS 4 shows an impressive H 2 production rate of 3345.26 μmol h –1 g –1, a significant improvement over the individual performances of WO 3 and Cu 3 SnS 4 . Moreover, WO 3 /Cu 3 SnS 4 demonstrated the highest photocatalytic tetracycline degradation efficiency, achieving 99.4% degradation within 90 min of illumination. An efficient S-scheme heterojunction system with a well-aligned band structure was successfully constructed. This design effectively extends their lifetime, allowing the heterojunction to achieve maximum efficiency in the light reaction.