Defect-Engineered F-ZnO@V2O5– x Heterostructures for Visible-Light-Driven Environmental Remediation

Abstract

Fluorine-modified ZnO anchored onto oxygen-deficient vanadium pentoxide (F-ZnO@V2O5–x) heterostructures were designed to enhance visible-light photocatalytic activity for environmental remediation applications. The materials were synthesized via a facile wet-chemical route followed by controlled thermal treatment, where ZnO nanoparticles derived from zinc acetate were fluorine-modified using sodium fluoride and deposited onto synthesized V2O5–x. The resulting composites with ZnO loadings of 5, 10, 15, and 20 wt %, designated as FZV-1, FZV-2, FZV-3, and FZV-4, respectively, were systematically characterized to elucidate structural, chemical, and optical properties. X-ray diffraction confirmed the coexistence of wurtzite ZnO and orthorhombic V2O5–x phases, while spectroscopic analysis verified fluorine incorporation and the presence of oxygen vacancies. Electron microscopy revealed uniform dispersion of F-ZnO nanoparticles on layered V2O5–x, forming intimate interfacial contact. Optical and electrochemical analysis indicated enhanced visible-light absorption and favorable band alignment. The optimized FZV-3 composite exhibited efficient visible-light-driven photodegradation of multiple organic dyes (MB, CV, and CR) as well as the pharmaceutical pollutant tetracycline hydrochloride (TC-HCl). Photocatalytic activity was examined under varying dye concentrations and catalyst dosages, with the 15 wt % F-ZnO@V2O5–x composite exhibiting the most effective results under visible-light irradiation. These outcomes highlight the role of defect-assisted oxide heterostructuring as an effective strategy for environmental photocatalysis.