Synergistic enhancement of the photocatalytic and antibacterial activities of cerium and tin-doped zinc sulfide nanoparticles

The persistence of toxic dye contaminants in textile effluents remains a significant environmental concern; however, nanocatalysts offer an efficient route for their degradation and removal from wastewater. In this study, zinc sulfide nanoparticles (ZnS NPs) doped with cerium (Ce) and tin (Sn) were used to examine photocatalytic degradation of textile dyes under visible light. Chemical precipitation was employed to produce Ce- and Sn-doped ZnS NPs at different weight percentages (1, 3, 5, and 10 wt.%). The doped ZnS NPs’ cubic close-packed structure was confirmed by X-ray diffraction analysis, whereas their functional groups, optical, thermal stability, and magnetic properties were examined by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, thermogravimetric analysis/differential thermal analysis, and electron paramagnetic resonance analyses. Surface morphology was characterized by field-emission scanning electron microscopy and transmission electron microscopy. Among the synthesized samples, the 5-wt.% Ce- and Sn-doped ZnS NPs showed superior photocatalytic efficiency toward the degradation of two model pollutants, bromophenol blue (BPB) and crystal violet (CV), under natural sunlight irradiation. Notably, Sn-doped ZnS NPs demonstrated higher photodegradation efficiency than Ce-doped samples, achieving maximum degradation efficiencies of 94.2% for BPB and 95% for CV within 120 min. Furthermore, recyclability studies confirmed that Sn-doped ZnS NPs could be reused effectively for multiple degradation cycles. Moreover, Sn-doped NPs demonstrated superior antibacterial and antioxidant properties, in addition to their photocatalytic performance, underscoring their potential as versatile multifunctional nanocatalysts for integrated environmental remediation applications.