Insight into the Local Surface Plasmon Resonance Effect of Pt-SnS₂ Nanosheets in Tetracycline Photodegradation

Constructing highly efficient catalysts for the degradation of organic pollutants driven by solar light in aquatic environments is a promising and green strategy. In this study, a novel hexagonal sheet-like Pt/SnS₂ heterojunction photocatalyst is successfully designed and fabricated using a hydrothermal method and photodeposition process for photocatalytic tetracycline (TC) degradation. The optimal Pt/SnS₂ hybrid behaves with excellent photocatalytic performance, with a degradation efficiency of 91.27% after 120 min, a reaction rate constant of 0.0187 min^-1, and durability, which can be attributed to (i) the formation of a metal/semiconductor interface field caused by loading Pt nanoparticles (NPs) on the surface of SnS₂, facilitating the separation of photo-induced charge carriers; (ii) the local surface plasmon resonance (LSPR) effect of Pt NPs, extending the light absorption range; and (iii) the sheet-like structure of SnS₂, which can shorten the transmission distance of charge carriers, thereby allowing more electrons (e) and holes (h) to transfer to the surface of the catalyst. This work provides new insights with the utilization of sheet-like structured materials for highly active photocatalytic TC degradation in wastewater treatment and environmental remediation.