Fe-W co-doped V2O5 nanostructures with enhanced oxygen vacancy generation for photocatalytic dye degradation

Nanoparticles of V2O5 with dilute doped Fe-, W-, and Fe-W co-doped were prepared by using wet chemical sol–gel method. Structural analysis confirmed the dominant orthorhombic α-V2O5 phase with a minor monoclinic V3O7 phase, whose fraction increased with doping. Rietveld refinement, and electron density (ED) mapping revealed balanced structural distortion, a strong synergistic effect and enhanced phase stability in Fe-W co-doped V2O5. Optical studies showed enhanced visible-light absorption and a reduced bandgap from 2.32 eV (pristine) to 2.14 eV (co-doped), and the formation of shallow and deep defect states that improve charge transfer and suppress recombination. Co-doping induced a morphological transformation from aggregated nanorods to porous, well-aligned nanowires with uniform elemental distribution. Electronic structures confirmed increased V4+ concentration and higher oxygen vacancy density, optimizing redox active sites. Thus, defect engineering and dual-phase evolution synergistically enhance the photocatalytic performance of co-doped V2O5. Consequently, the co-doped V2O5 sample showed exhibited superior photocatalytic performance, following pseudo-first-order kinetics, achieving 99.25% of MB and 98.1% of MO dyes in 30 min under direct sun light.