Shining Light on ZnIn ₂ S ₄ Photocatalysts: from Structural Tailoring to Energy Conversion Applications

Abstract Zinc indium sulfide (ZnIn ₂ S ₄ ) has emerged as a promising candidate for visible‐light‐driven catalysis due to a narrow bandgap, rapid generation rate of photogenerated electrons, and high stability in water solutions. Herein, new research advancements of ZnIn ₂ S ₄ or ZnIn ₂ S ₄ ‐based photocatalysts in recent years are comprehensively summarized, focusing on reducing the recombination rate of photogenerated electrons and holes. In this review, structural tailoring strategies are explored, such as morphology control, vacancy engineering elements doping, and combination with other compounds for hetero and homojunction construction. It is also worth noting that a conclusion of a well‐rounded application of ZnIn ₂ S ₄ and ZnIn ₂ S ₄ ‐based materials in energy conversion and storage, including conventional areas like hydrogen generation and novel areas (e.g., carbon dioxide reduction, nitrogen fixation, batteries, and sterilization), is introduced in the following context. This review bridges fundamental insights with practical engineering strategies (e.g., solid‐solution engineering and heterostructure design) to guide the development of next‐generation ZnIn ₂ S ₄ ‐based materials for sustainable energy applications.