Physical, thermal and optical study of Bismuth modified boro-vanadate glasses: V2O5-B2O3-Bi2O3.

The present study investigated the influence of varying Bi₂O₃ concentration on physical, thermal and optical properties of boro-vanadate glasses. Glasses with the composition of 60V₂O₅−(40-x) B₂O₃-xBi₂O₃ were synthesized; where x=5-25 mol% (with step size of 5 mol%). The non-crystalline nature of prepared samples was confirmed with X-ray diffraction (XRD) patterns. The different properties of the processed samples were ascertained using a density measurement instrument, Differential scanning calorimeter (DSC) and ultra-violet visible spectrometry (UV-visible). The glass samples' density, molar volume, and crystalline volume increases while the band gap decreases as Bi₂O₃ content increases. The band gap was found in the range of 1.63 eV to1.92 eV. Glass transition temperature (T_g) showed a decreasing trend but increased for a sample x=20 mol%. Various other calculated parameters include refractive index (n), molar refractivity (R_m), metallization criterion (M), electronegativity (χ), optical basicity and electron polarizability (αᵒ). The high refractive index values (2.77-2.92) and low metallization criterion (ranging from 0.286-0.310) observed across all samples indicate the potential suitability of these glasses for non-linear optical purposes. [ABSTRACT FROM AUTHOR]