Synthesis of novel AgO-doped vanadium–borophosphate semiconducting glasses and investigation of their optical, structural, and thermal properties

Ag-doped vanadium–borophosphate glasses having 46V₂O₅–46P₂O₅–(8 − x)B₂O₃–xAgO as the base structure have been successfully synthesized with different compositions of AgO (x = 0, 2, 4, 6, 8 mol%) by the conventional melt-quenching technique. Density and molar volume values were calculated by Archimedes principle. The transmittance and absorbance spectra, XRD, and FTIR measurements of the glasses were performed at room temperature. While XRD data showed that the glasses had an amorphous structure away from crystallization, FTIR spectra showed that vanadium and phosphate compounds forming the glass network consisted of VO₄, VO₅ and PO₃, PO₂ structural units, respectively. It was observed that AgO, which replaces B₂O₃, acted as a modifier in the glass network. Direct and indirect band gaps of synthesized glasses were calculated using Tauc method. Urbach energies were also calculated. The glass transition temperature, crystallization temperature, and melting temperature values of the samples were determined with differential scanning calorimetry (DSC) in the range of room temperature to 1000 °C.