Glass systems of composition xAg2SO4-20Ag2O-(80-x) [0.50 B2O3-0.50 TeO2], where x = 5, 10, 15, 20, 25 and 30mol% were prepared by melt-quenching technique. Frequency- and temperature-dependent conductivity measurements were carried out in the frequency range 10 Hz to 10 MHz and at a temperature range of 303-353K, respectively. DC conductivities exhibited Arrhenius behavior over the entire temperature range with a single activation barrier. Addition of Ag2SO4 expands the glass network and, consequently, conductivity increases. This suggested that the structure and network expansion were the key parameters for enhancing conductivity. Impedance spectra of these glasses showed a single semicircle, indicating one type of conduction. AC conductivity behavior of the glasses was analyzed using both single power law and Kolhrauh-William-Watts stretched exponential relaxation function. The power-law exponent was temperature-dependent, while the stretched exponent was insensitive to temperature. Scaling behavior had also been carried out using reduced plots of conductivity with frequency, which suggested the ion transport mechanism remained unaffected by temperature and composition.

Dielectric Relaxation and Ion Transport in Silver-Boro-Tellurite Glasses. B.Sujatha, C.Narayana Reddy, R.P.S.Chakradhar: Philosophical Magazine, 2010, 90[19], 2635-50