Relaxation dynamics in AgI-doped silver vanadate superionic glasses

Abstract

Relaxation dynamics of Ag⁺ ions in several series of AgI-Ag₂O-V₂O₅ superionic glasses has been studied in the frequency range from 10 Hz to 2 MHz and in the temperature range from 93 to 323 K. The composition dependence of the dc conductivity and the activation energy of these glasses has been compared with those of AgI-doped silver phosphate and borate glasses. The frequency-dependent electrical data have been analyzed in the framework of conductivity formalism. We have obtained the mobile ion concentration and the power-law exponent from the analysis of the conductivity spectra. We have observed that the concentration of Ag⁺ ions is independent of temperature and the conductivity is primarily determined by the mobility. A fraction of the Ag⁺ ions in the glass compositions are involved in the dynamic process. We have also shown that the power-law exponent is independent of temperature. The results are also supported by the temperature and composition independence of the scaling of the conductivity spectra.