Optical and structural investigations of zinc phosphate glasses containing vanadium ions

• ZnO–P2O5 glasses doped with V2O5 have semiconducting behavior.
• The formation of non-bridging oxygen's is related to the effect of V2O5 dopants.
• Unshared V–O bonds are observed in ZnO–P2O5 glasses.
• Optical basicity is related to the increase of the charge on oxygen atoms.

Zinc phosphate glasses containing vanadium ions were studied from combined optical and infrared absorption spectral measurements. Density and molar volume calculations were obtained and interpreted in the view of non-bridging oxygen formation in glasses. Vanadium ions are assumed to exist in lower valences, mainly V3 + ions with sharing of V4 + ions. Optical band gap for the base zinc phosphate glass is estimated to be 3.75 eV. This value was observed to decrease as the vanadium oxide content increases and it was found to be 2.05 eV at the highest doping of vanadium content, 8.4 mol% V2O5. The refractive indexes for the studied glasses were evaluated from the optical band gap values and their values are observed to increase with increasing the vanadium content. Electronic oxide polarizability and optical basicity were investigated for the studied glasses. Unshared V–O bonds observed from infrared absorption spectra leading to increasing non-bridging oxygen bonds in the host glass.