The enhanced mechanism of ZnIn2S4-CoFe2O4-BC activated peroxomonosulfate under visible light for the degradation of fluoroquinolones

Visible light is a sustainable method for activation peroxomonosulfate (PMS). In this study, the ZnIn₂S₄-CoFe₂O₄-BC (ZIS-CFO-BC) composite photocatalytic material was synthesized by two-step hydrothermal and solvothermal methods to enhanced the efficiency of sunlight utilization. The morphology analysis revealed ZIS and CFO particles are uniformly dispersed on the Biochar (BC) surface, forming a stable heterojunction interface. A 96.39 % removal of enrofloxacin (ENR, 2 mg/L) was achieved within a 30 min period by the Vis/ZIS-CFO-BC system. According to the quenching and EPR tests, SO₄^•−, h⁺, •OH, and ¹O₂ were identified as the primary active species. Valence changes were observed for both Co and Fe, indicating that this is primary site for PMS activation. The findings of the cycling and co-existing ions experiments illustrate that ZIS-CFO-BC exhibits remarkable potential for various applications. This research presents a new recyclable green material that efficiently utilizes sunlight to enhance the Fenton-like system.