Study on the Modification in Physical and Optical Properties of Lithium Bismuth Borate Glasses with Vanadium Oxide Addition

Abstract

The series of the glasses with general formula (40-x)Li₂O:30B₂O₃:30Bi₂O₃:xV₂O_5, with x = 0, 0.5, 1.0, 1.5 and 2.0 mol%  was prepared using conventional quenching technique. The glass transition temperature T_g for these samples were determined from Differential Thermal Analysis. The glass transition temperature increases beyond 0.5 mol%. It was found that the glasses under study consist of randomly connected BO₃ & BO₄ structural units. The density and molar volume of glasses were found to depend on V₂O₅ content. Initially the density increases, molar volume and glass transition temperature decrease with the addition of V₂O_5. This suggests that when V₂O₅ is added to the glass initially up to 0.5 mol% it may be entering as a modifier. Beyond 0.5 mol% density decreases and molar volume increases as V₂O₅ goes as former. This reveals the role of V₂O₅ as a glass network former beyond 0.5 mol%. Optical band gap energy decreases and cut off wavelength increases with increase in V₂O₅ content. Author wish to study the effect of transition metals on the optical properties of the lithium bismuth borate glasses