Rational design of novel ternary Sm2WO6/ZnO/GO nanocomposites: An affordable photocatalyst for the mitigation of carcinogenic organic pollutants

Abstract

In this scenario, a ternary type of novel Sm2WO6/ZnO incorporated on GO (SWZG) nanocomposites were synthesized by the ultrasonic-assisted hydrothermal route and confirmed by various characterization techniques. The diffraction peaks obtained from Powder-X-ray analysis reveals good crystalline nature of as preparedSWZG composite. Scanning Electron Microscopereveals the red algae like the hexagonal structure of SWZ composition an elongated form on the graphene oxide sheet. The Transmission electron spectroscopy reveals the confirmation of algae like structure of Sm2WO6 and ZnO in elongated form on the surface of the graphene oxide sheet. The elemental composition and the oxidation state of C, Zn, O, Sm and W were confirmed by X-ray Photoelectron Spectroscopy analysis. The charge separation efficiency of the photogenerated electron-hole pairs in SmW, SmWZ and SmWZG was confirmed by photoelectrochemical measurements. SWZG catalyst shows superior photocatalytic activity towards the degradation of Ciprofloxacin (CIP) and Methylene blue (MB) with the efficiency of 96.92 & 98.24 % within 90 and 25 min. In Reactive Oxidative Species study, photogenerated holes and superoxide radicals are the main reactive species in the CIP and MB degradation process. Besides, the stability and reusability of the catalysts were confirmed by the recycle test. In the CIP degradation pathway, the reaction intermediate (7-amino-1-cyclopropyl-6-fluoro-2-hydroxy-4-oxo-1,4-dihydro quinolone-3-carboxylic acid (m/z 278.07)) were elucidated by Gas Chromatography–Mass Spectroscopy analysis and a feasible degradation pathway was also proposed. Finally, the ternary SWZG composite would be a promising candidate for the degradation of organic pollutants.