Structural, Thermal, Optical and DC Conductivity Studies of 30TeO2-40B2O3-(30-x)BaO-xNa2O (0 ≤ x ≤ 30 mol%) Glass System

High thermal stable glasses of 30TeO(2)-40B(2)O(3)-(30-x)BaO-xNa(2)O (0 <= x <= 30 mol%) were synthesized by melt quenching technique. Experimental tools like XRD, EDX, XPS, FTIR, Raman, DSC, Optical absorption and DC conductivity were used for characterization. The broad hump in XRD and endotherms in DSC asserted the short range order of samples. The changes in physical properties were correlated with structure and other investigations. Vibrational and DSC investigations displayed that bond strength of Te4+-O/B3+-O is higher in presence of Ba2+ than Na+ ions. The addition of Na2O decreased the glass transition temperature (T-g) and increase fragility for these glasses. The values of the optical band gap (E-opt) and Urbach energy (Delta E) were observed in 3.49-3.23 and 0.312-0.384 eV range, respectively. Variations in all the optical properties suggest that Na2O converted the Lewis acid into Lewis base glass. DC conductivity studies disclose that conductivity increases with raise in Na2O mol% and temperature.