Integration of Ag₂S QDs in 3D Zn₃V₂O₈ nanoflower for visible light driven effective photocatalytic degradation of rifampicin: Insights into preparation, mechanism and by-product toxicity evaluation

Water contamination is regarded as one of the most important concerns in the last decade and its crucial to develop an efficient and productive technique to remediate organic pollutants from waters. Photocatalytic degradation processesare advanced oxidation procedure and a promising technique for the degradation of organic pollutants. In this study, we fabricated Ag₂S/Zn₃V₂O₈ nanocomposite (AS/ZVO NCs) for the degradation of rifampicin (RIF) by ultrasonicated co-precipitation strategy. The NCs was optimally synthesized with varying deposition concentrations, among which 5%-Ag₂S/Zn₃V₂O₈ (5%-AS/ZVO) exhibited superior photocatalytic activity (95.5%) under visible light irradiation. Moreover, the experiments were conducted at diverse operational parameters such as different NCs dosage, different concentration of RIF, pH, and ions, to investigate the impact on the photocatalytic degradation of RIF. Notably, XRD and XPS results of used 5%-AS/ZVO NCs demonstrated commendable stability and possess sustained integrity in structure after six consecutive cycle tests. The scavenging study and radical trapping experiments confirmed the formation of ^•OH and O₂^•- during photocatalytic reaction. The mechanism of photocatalytic degradation of RIF by 5%-AS/ZVO NCs was proposed and the pathway was predicted based on the GC-MS results. The current study provides a comprehensive understanding for designing efficient photocatalysts for the environmental remediation applications.