Synergistic photocatalysis of VO2-A/g-C3N4 composites for efficient degradation of anionic and cationic dyes: Towards a sustainable environmental solution

Abstract

Due to the outflow of dye effluent from numerous industrial operations, dye pollution is a severe environmental issue. Because of its efficiency and environmental friendliness, photocatalytic degradation is a technology promising for treating dye pollutants. This study used a simple hydrothermal process to synthesise VO2-A/g-C3N4 nanocomposite and its photocatalytic activity for the breakdown of anionic dyes (Xylenol Orange (XO, Rose Bengal (RB)) and cationic dyes (Crystal Violet (CV), Auramine O (AO)) and Mix dyes (1:1 mixture of anionic and cationic dyes) were assessed. XRD, XPS, SEM, FTIR, Photoluminescence, TEM, UV-DRS and BET analysis were used to characterize the nanocomposite.SEM and TEM analyses revealed a distinct morphology of the VAG-4 nanocomposite, with small, irregular VO2-A nanoparticles dispersed and wrapped around the g-C3N4 surface. UV-DRS analysis, using the Tauc relation, indicated that VO2-A incorporation shifted the absorption edge to longer wavelengths, with VAG-4 showing a peak at 487 nm (1.91 eV). BET analysis of VAG-4 shows a specific surface area of 47.1 m2/g, a pore volume of 0.2125 cm3/g, and an average pore size of 27.9 nm, supporting its potential for effective photocatalytic applications. We assessed the photocatalytic activity ofVO2-A/g-C3N4 nanocomposite for the degradation of the anionic dyes (RB, XO), cationic dyes (AO, CV) and Mix dyes. The results demonstrated that the VAG-4 nanocomposite with degradation percentages of RB (83.5 %), XO (75.5 %), AO (73.4 %), and CV (78.2 %) exhibited more enhanced photocatalytic activity than the individual precursors. The nanocomposite’s outstanding photocatalytic activity suggests that it has the potential for practical appli cations in environmental cleanup.