A review on potential sulfide-based ternary chalcogenides for emerging photo-assisted water purification applications

Sulfide-based ternary chalcogenides have been recognized widely as exceptional photocatalysts, thanks to their narrow band gap enabling them to harvest solar energy to the maximum extent. They provide excellent optical, electrical, and catalytic performance and are of abundant use as a heterogeneous catalyst. Among sulfide-based ternary chalcogenides, compounds exhibiting AB₂X₄ structure form a new class of materials with excellent stability in photocatalytic performance. In the AB₂X₄ family of compounds, ZnIn₂S₄ is one of the top performing photocatalyst for energy and environmental applications. However, to date, only limited information is available on the mechanism behind the photo-induced migration of charge carriers in ternary sulfide chalcogenides. Ternary sulfide chalcogenides with their visible region activity and substantial chemical stability greatly depend on crystal structure, morphology, and optical characteristics for their photocatalytic activity. Hence, in this review, a comprehensive assessment of the reported strategies for enhancement of the photocatalytic efficiency of this compound is presented. In addition, a meticulous investigation of the applicability of ternary sulfide chalcogenide compound ZnIn₂S₄, in particular, has been delivered. Also, the photocatalytic behavior of other sulfide-based ternary chalcogenides for water remediation applications has also been briefed. Finally, we conclude with an insight into the challenges and future advancements in the exploration of ZnIn₂S₄-based chalcogenide as a photocatalyst for various photo-responsive applications. It is believed that this review could contribute to a better understanding of ternary chalcogenide semiconductor photocatalysts for solar-driven water treatment applications.