Photocatalytic degradation of anionic dye using well-crystalline SnWO4 polyoxometalate

Abstract

Rose Bengal (RB) is well known anionic dye and considered as one of the major water pollutants. It can be hazardous to human and aquatic life. Polyoxometalates play major role for the decomposition of such type of pollutants. In this study, cubic tin tungsten oxide nanoparticles (β-SnWO4-NPs), a polyoxometalate, had been synthesized by sol-gel method and physically characterized by XRD, FT-IR, Raman, UV-DRS, PL, XPS, and SEM. Photocatalytic performance was evaluated by photodegradation of RB under visible light irradiation, and corresponding photodegradation mechanism was also proposed. The role of various reaction parameters such as catalyst amount, dye concentration and solution pH were investigated. Under given parameters the degradation percentage of RB was found to ∼94.6% after 150 min. The cubic crystal structure and honeycomb morphology of the β-SnWO4-NPs endows excellent photocatalytic properties. The radical scavenger investigations showed that photogenerated h+, O2 •−, and •OH radicals were responsible for RB degradation. The obtained results can be effectively used in future for the wastewater treatment.