Synthesis, Structure and Dielectric Characteristics of Tellurovanadate Glasses Containing Bismuth Oxide.

Two series of glasses with compositions (90 - x)TeO2-xV2O5-10Bi2O3 and (80 - x)TeO2-xV2O5-20Bi2O3, where x = 20, 30, 40 mol %, were synthesized. Glasses were obtained by the melt-quenching technique. The molar volume (33.48-48.37 cm3/mol) and oxygen packing density (71.69-77.64 mol/cm3) were calculated based on experimental density measurements. Both parameters increase with the increase in V2O5 and the decrease in TeO2 content. Infrared spectra were recorded in the range of 2000-400 cm-1 and Raman spectra in the 90-1280 cm-1 range. The C1s, O1s, Te3d, V2p and Bi4f photoelectron lines were recorded. The dielectric characteristics of the glasses were measured by impedance spectroscopy at room temperature in the frequency range from 100 Hz to 1 MHz. The glasses in the studied system demonstrate a strong dependence on the composition, with the occasional addition of high contents of TeO2 and V2O5 leading to a significant change in the dielectric properties of the samples.