AC Conductivity and Electrical Modulus Studies on Lithium Vanadophosphate Glasses

Abstract

The lithium vanadophosphate (LVP) glasses were synthesized through a conventional melt quench method for various modifier (m) to formers (f) ratios (m/f) [m%Li2O/f%{0.3V2O5+0.7P2O5}, where them/f=0.43, 0.66, 1.0, 1.5, and 1.63]. Nature, structure, and glass transitionTgtemperature for the prepared LVP samples were characterized by X‐ray diffraction, FTIR, and DSC techniques, respectively. Impedance measurements were made for the variousm/fratios of LVP glasses at 423 K and above temperatures. The bulk conductivity (σ) and the activation energy (Ea) for the LVP glass samples were calculated, respectively, from the analyzed impedance data of the variousm/fratios measured at different temperatures, using Boukamp equivalent circuit software. The best conducting [σ=4.83 × 10−8S/cm at 423 K]m/fratio of LVP was found to be 60%Li2O–40% [0.3V2O5+0.7P2O5] and its activation energy (Ea)=0.59 eV. AC conductivity was calculated from the impedance data and analyzed using Jonscher's power law for variousm/fratios of the LVP glasses at different temperatures. The power law exponents, evaluated from AC conductivity of the LVP glasses, exhibited a non‐linear behavior with temperatures. Kohlrausch–William–Watts stretched exponential function was used to fit the calculated modulus data and ion relaxation behavior was studied for the LVP glasses.