The effect of PbI2 on electrical conduction in Ag2O-V2O5-B2O3 superionic glass system

Conductivity measurements and modulus formalism have been used to study the transport properties of PbI2 doped silver boro-vanadate glasses prepared by melt quenching technique. The samples are characterized by XRD and DSC measurements. A correlation between Rτ, the decoupling index and σDC has been discussed. The observed conductivity values suggest enhancement in conductivity by the introduction of PbI2 salt in the host glass matrix. AC conductivity data are analyzed by fitting the data to Jonscher's universal power law, σ′(ω) = σDC + Aωn. The power law exponent, n, is found to be independent of temperature and composition. The experimental modulus spectra are analyzed and calculated the stretched exponential constant β using the non-linear KWW decay function. Furthermore, the scaling of both ac conductivity and electric modulus at different temperatures is found to merge near perfectly on to a single master curve suggesting that all the dynamic processes possess good time temperature superposition.

Research Highlights
► In the quaternary glass system, PbI2-Ag2O-V2O5-B2O3, formation of AgI and PbO by exchange reaction between PbI2 and Ag2O, enhances the conductivity of the base glass Ag2O-V2O5-B2O3.
► A good correlation between conductivity and the decoupling index Rτ values for different compositions is observed.
► Electrical conductivity study shows that conductivity as well as conductivity relaxation, both the processes, is activated via the same mechanisms.