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Semiconductor‐based Z‐scheme heterojunction photocatalysts have received considerable attention for solar energy conversion and environmental purification due to their spatially separated reduction and oxidation sites, effective separation and transportation of photo‐excited charge carriers and strong redox ability. With their wide visible‐light responsive range and high photocatalytic activity, metal sulphide is an important material in developing photocatalysts. This review summarizes and highlights recent research progress in sulphide‐based direct Z‐scheme photocatalysts, followed by analysis on the limitations over all‐solid‐state Z‐scheme photocatalyst. Furthermore, the applications and characterization methods of sulphide‐based direct Z‐scheme photocatalyst are summarized. Finally, the challenges and perspectives of sulphide‐based Z‐scheme photocatalyst are discussed. A to Z! Sulphide‐based Z‐scheme photocatalysts are reviewed in this paper about the mechanism fundamentals, recent research progress in the applications in photocatalysis, evidence of Z‐scheme mechanism and perspective on challenges and future developments. [ABSTRACT FROM AUTHOR]

Photocatalytic reduction of CO 2 to solar fuels is an ideal approach to simultaneously solve the global warming and energy crisis issues. Constructing a direct Z-scheme heterojunction is an effective way to overcome the drawbacks of single-component or conventional heterogeneous photocatalysts for photocatalytic CO 2 reduction. Here, a novel type of direct Z-scheme g-C 3 N 4 /SnS 2 heterojunction was constructed by depositing SnS 2 quantum dots onto the g-C 3 N 4 surface in situ via a simple one-step hydrothermal method. l -Cysteine not only acted as the sulfur source, but also grafted ammine groups onto g-C 3 N 4 in the hydrothermal process, which greatly enhanced the CO 2 uptake of the composite. XPS analysis and density functional theory (DFT) calculation show that electron transfer occurred from g-C 3 N 4 to SnS 2 , resulting in the formation of interfacial internal electric fields (IEF) between the two semiconductors at equilibrium. As a result, Z-scheme charge transfer took place under photoexcitation, with the electrons in SnS 2 combining with the holes in g-C 3 N 4 , which improved the extraction and utilization of photoinduced electron in g-C 3 N 4 . The g-C 3 N 4 /SnS 2 hybrid shows superior photocatalytic CO 2 reduction as compared with individual g-C 3 N 4 and SnS 2 , which should be attributed to the IEF-induced direct Z-scheme as well as improved CO 2 adsorption capacity. In situ FTIR spectra illustrate that HCOOH appeared as an intermediate during the CO 2 conversion, which can only be generated by g-C 3 N 4 according to the energy level of the photoinduced electrons, further confirming the Z-scheme configuration for the g-C 3 N 4 /SnS 2 system. [ABSTRACT FROM AUTHOR]