Role of vanadium ions on structural, optical and electrochemical properties of the vanadate-lead glasses

•The increase of the V2O5 content produces pyrovanadate and orthovanadate units.•The vanadium species have significant effect on the resonance lines.•A decrease of the optical band gap energy

New different series of xV2O3∙(100 − x)[4PbO2·Pb] glasses were prepared by melt-quenching method in a wide range of compositions defined by the parameter x = 0–30 mol% V2O5. InfraRed (IR) data reveal that by increasing the V2O5 content, the glass network was transformed into a mixture of modified [VO4] structural units, namely pyrovanadate and orthovanadate ones. The UltraViolet–Visible (UV–VIS) spectra show that addition of V2O5 produces a gradual shift of the absorption edge towards the higher wavelength side (indicating the increase in concentration of vanadyl species) and a decrease of the gap energy.The shape of the Electron Spin Resonance (ESR) spectra changes with increasing the V2O5 content suggesting that the interactions between vanadium centers strongly depend on x parameter which plays an important role. A hyperfine structure becomes visible in the glass with x = 20 mol% V2O5 suggesting modifications of the glass structure caused by the network modifier. If the network is moderately disrupted the formation of Pb+ 2–V+ 4 pairs was coupled through the oxygen atom or the interactions within V+ 4–O–V+ 5 chains mask hyperfine structure.The shape of cyclic voltammograms, redox waves and good reversibility of the x = 20 mol% V2O5 glassy electrode depends on the electrolyte acidity and electrochemically active species present in the glass network.