High efficient photocatalytic treatment of cationic dye and antibacterial activity via wet chemically synthesized Zn-doped BiVO4 nano photocatalysts

Abstract

This study presents the synthesis of dual-function Zn_x-doped BiVO₄ (x = 0 %, 2 %, 4 %, 6 %) nanocatalysts using a cost-effective wet chemical method, focusing on their application in dye degradation and biomedical fields. X-ray Diffraction (XRD) results confirmed the formation of monoclinic bismuth vanadate (BiVO₄) crystal system with increasing grain size at higher Zn concentrations. High-Resolution Transmission Electron Microscopy (HRTEM), Selected Area Electron Diffraction (SAED) revealed merged nanosphere and nanorod-like structures with crystalline plane distances of 0.352 nm–0.376 nm. Field Emission Scanning Electron Microscopy (FESEM) shows that morphology evolution with Zn doping, while Energy Dispersive X-ray Analysis (EDAX) verified stoichiometric accuracy. High-resolution X-ray Photoelectron Spectroscopy (XPS), Raman spectra and Fourier Transform Infrared (FTIR) Spectroscopy analysis highlighted the compositional and peak shifts for various concentration of Zn doping. The nanomaterials exhibited band gap values of 2.54 eV–2.46 eV, with Brunauer-Emmett-Teller (BET) analysis revealing enhanced pore volume and surface area. Among all, wt.6 % Zn-doped BiVO₄ showed superior photocatalytic performance, achieving 91.2 % Methylene Blue (MB) dye degradation with excellent recyclability. Zn-doped BiVO₄ nanoparticles demonstrated marginally increased antimicrobial activity against Gram-negative bacteria (E. coli, Y. pestis, and P. aeruginosa) compared to Gram-positive bacteria (B. subtilis and S. aureus). Photocatalytic and Antibacterial results are emphasizing the Zn-doped BiVO₄ as a potential of nanocatalysts for environmental and biomedical applications.