Effect of acid catalyst concentration on structure and conductivity studies of quaternary lithium-based glasses synthesized by sol-gel route

Lithium phosphoborosilicate (LPBS) glasses were synthesized through sol-gel process with various nitric acid concentrations, as a catalyst. Measuring the XRD patterns for the dried gel heat-treated at different temperatures optimized the synthesis temperature for the LPBS glasses. The effect of acid catalyst concentrations on the structural properties of the LPBS glasses was studied using XRD, FTIR, and DSC. Impedance measurement was carried out at different temperatures on the LPBS samples synthesized by sol-gel route with various nitric acid concentrations and impedance data were analyzed using the Boukamp equivalent circuit software. The bulk conductivity of the LPBS samples synthesized with each concentration of nitric acid, as a catalyst, was calculated from the analyzed impedance data. It was found that the LPBS sample synthesized with 2.5 N nitric acid concentration showed the highest conductivity, σ=2.28 (± 0.02)×10−7 S cm−1 at 443 K. The activation energy (Ea) was obtained from Arrhenius plots of the dc conductivity of each LPBS glassy samples and was found to be 0.39 (± 0.02) eV for the highest conducting LPBS sample.