Synthesis and Characterization of WO3/BiVO4/Graphene Ternary Nanocomposites for the Photodegradation of Methlyene Blue and Tetracycline

Abstract

In this study, a hydrothermal method was employed to synthesize the ternary nanocomposites comprising WO3/BiVO4/Graphene, all driven by visible light. The characteristics of these nanocomposites were interpreted through techniques such as UV–Vis, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and photoluminescence spectroscopy (PL). The enhanced performance of the composite, attributed to its heightened capability for separating charge carriers, outperformed that of the individual semiconductor components. The PL results validated the composite's improved charge separation. The nanocomposites have weaker PL peaks, indicating slower e−/h+ recombination. The balanced concentrations of the mixed semiconductors in the composite affected both PL intensity and photodegradation efficiency. The photocatalytic degradation of methylene blue (MB) and tetracycline (TC) was observed by nanocomposites. The heterogeneous nanocomposite WOBV/G-5 with 0.03 mg graphene content has a better photocatalytic activity for both MB (63 %) and TC (80 %) than other concentrations. It has also been investigated using TOC and COD analysis. Moreover, zeta potential analysis and pH analysis have been done to check the conductivity of optimized photocatalyst. Additionally, to check the stability of WOBV/G-5 photocatalyst, recyclability test that shows 58 % degradation rate after five cycles and analysis of XRD after recyclability have also been performed. Role of active species (h+, O2−, and OH.) was observed by using different scavengers (EDTA, BQ, and IPA) in trapping experiment that plays a vital role in photocatalytic degradation process.