Metal-sulfide-based heterojunction photocatalysts: Principles, impact, applications, and in-situ characterization

Semiconductor photocatalysis is a new sustainable development technology that has demonstrated remarkable potential in the fields of energy-production and environmental-protection. However, single photocatalyst usually does not possess both strong redox fast charge-separation properties, greatly limiting efficiency. Heterojunction photocatalysts can perfectly solve this problem by providing multiple reactive sites charge separation migration, elevating photocatalytic efficiency to higher level. Metal sulfides are family compounds composed metals sulfur (e.g., CdS, CuS, MoS2, In2S3, ZnIn2S4, ZnxCd1–xS) preferred choices for heterojunction due their narrow bandgaps, broad visible-light absorption ranges, convenient preparation methods. This review article introduces characteristics metal sulfides, summarizes methods synthesis, discusses various types metal-sulfide-based heterojunctions. The use such energy environmental-remediation applications subsequently discussed. In addition, roles transfer using in-situ characterization techniques. Finally, we discuss some application prospects challenges concerning photocatalysts.