Research Progress of NiS Cocatalysts in Photocatalysis

In recent decades, photocatalysis technology, a typical mild and environmentally friendly technique, can use sunlight to drive the oxidation/reduction reactions on the surface of catalysts. However, single semiconductor materials can hardly meet the requirements of photocatalytic application due to the low availability of visible light, quick e − − h + recombination, and the insufficiency of active sites. Cocatalysts are often introduced to solve the above problems. Among the numerous cocatalysts, NiS cocatalysts exhibit excellent properties, such as superior chemical stability, suitable band structure, and larger specific surface area, which can improve the photocatalytic efficiency of various semiconductors. Herein, the research progress of NiS cocatalysts in photocatalysis is reviewed. First, the structure of NiS and several common preparation methods are briefly introduced. Second, the NiS cocatalytic principle about how to achieve the effective separation of photogenerated carriers is introduced. Third, the methods to optimize the catalytic activity of NiS are mainly summarized. At the same time, the review summarizes the research progress of composite photocatalysts based on NiS cocatalyst. Finally, the review discusses the existing challenges and obstacles of NiS‐based photocatalytic systems and proposes feasible improvements and idea s to meet the future requirements of practical applications.