Advances and Prospects of Snln ₄ S ₈ ‐Based Photocatalysts: From Fundamentals to Applications

In recent decades, environmental remediation and renewable energy resources have garnered significant research attention, with photocatalysis demonstrating significant potential in both fields. Among various semiconductors, SnIn 4 S 8 is an earth‐abundant, indirect‐bandgap semiconductor characterized by a wide visible‐light response and suitable band edge potentials for facilitating numerous redox reactions, thereby holding promise for the development of high‐performance photocatalysts. However, its photocatalysis efficiency is still impeded by insufficient separation of photogenerated carriers and a lack of catalytically active sites. This review first evaluates the advantages and limitations of SnIn 4 S 8 as a photocatalyst based on its crystal structure and electronic (band) structure. Subsequently, we propose methodologies for the controllable synthesis of different SnIn 4 S 8 nanostructures, based on a comprehensive summary of previous synthesis methods. We then survey modification strategies for SnIn 4 S 8 ‐mediated photocatalysis, including microstructure regulation, heterojunction construction, and cocatalyst loading, while identifying the corresponding research gaps. Furthermore, we summarize and discuss recent advances in SnIn 4 S 8 ‐based photocatalysts for environmental remediation and solar energy conversion is summarized and discussed. Finally, we outline the challenges and future research directions for SnIn 4 S 8 ‐based photocatalysts to guide further development in this field.