A novel nanocomposite comprising Schiff base ligand functionalized zinc sulphide nanoparticles for heavy metal detection and photocatalytic dye degradation

ABSTRACT Herein, we report the detection and removal/degradation of metal ions and dye species using nanotechnology-based approach. A Schiff base (Sb) ligand has been prepared by a solvent-less method; post which, the ligand is used for functionalizing zinc sulphide nanoparticles (ZnS NPs) in the aqueous medium. The Sb–ZnS NPs proved to be a dual probe, viz., for the detection of Pb2+, Hg2+ and Fe3+ ions, and as a photocatalyst for the degradation of methylene blue (MB) dye. The experiments using the Sb–ZnS NP photocatalyst under daylight illumination revealed higher efficiency with 96% degradation of MB than that in the dark with only 66% degradation of the dye. Further, the degradation of the dye followed first-order rate kinetics with a higher rate constant for light-illuminated sample (16.3 × 10−4 min−1) than the one kept at dark (6.85 × 10−4 min−1). UV–Vis, PL, FT-IR, TEM and powder XRD analyses have been routinely used for the present investigation.