Enhanced sunlight-driven photocatalytic activity of SnO₂-Sb₂O₃ composite towards emerging contaminant degradation in water

This paper explains the preparation of SnO₂-Sb₂O₃ composite catalyst by solid state reaction process, and posteriorly employs as an alternative and promising photocatalyst for Brilliant Green (BG) dye degradation under solar irradiation. SnO₂ and Sb₂O₃ composite samples with varying proportions of SnO₂ and Sb₂O₃ were created, with 2–5 wt% SnO₂ added to the Sb₂O₃ sample. The synthesized samples were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDS) and UV–visible diffuse reflectance spectroscopy (UVDRS). The results showed that the 3% SnO₂-Sb₂O₃ sample presented the higher catalytic activity compared to the others, besides SnO₂ and Sb₂O₃ alone, reaching ~90% of decolonization and ~87% of COD removal at 180 min. This remarkable photocatalytic activity may be associated to its favorable band gap energy. Kinetic data fitted well with pseudo-first-order kinetic model. Therefore, the prepared SnO₂-Sb₂O₃ composite in this work can be considered as an effective photocatalyst for elimination of colored-contaminants, such as BG dye, from wastewater.