Effect of vanadium on the optical and physical properties of lithium borate glasses

• Vanadium substitution affects the physical and optical properties of lithium borate glasses.
• FTIR spectra reveal the bands shifting with the decrease in vanadium content.
• Average stretching force constant, network bond/volume and bulk modulus are calculated theoretically.
• The Urbach energy and optical band gap show a decreasing trend with decreasing concentration of V2O5.

In the present studies, the effects of vanadium substitution for 30Li2O–55B2O3-(15-x) ZnO–xV2O5, (0 ≤ x ≤ 7.5) glass system on the physical and optical properties have been investigated. V2O5 can work as a conditional glass former and its incorporation into glass yields vanadyl ions (VO2 +), which causes considerable change in the structure of glass. The glass composition can be tailored by optimizing the zinc and vanadium content so as to obtain the desirable semiconducting or optical applications. Physical parameters like density, molar volume, molar electro-negativity, oxide electro-negativity, basicity moderating parameters, ionic concentration, and inter-ionic distance are obtained for all the glass compositions. Characterization techniques like X-ray diffraction (XRD), UV–Visible and Fourier transforms infra-red spectroscopy (FTIR) are used to yield the structural and optical parameters. Average stretching force constant, network bond/volume and bulk modulus are calculated theoretically and correlated with each other. The Urbach energy as well as optical band gap shows a decreasing trend with decreasing concentration of V2O5 with respect to ZnO content.