Physico-chemical properties of Bismuth nitrate filled PVA–LiClO4 polymer composites for energy storage applications

Abstract

A series of polymer composites were prepared by the addition of Bismuth nitrate (Bi(NO3)3) and Lithium perchlorate (LiClO4) to poly(vinyl alcohol) (PVA) polymer matrix by solvent casting method. The microstructures and surface morphology were systematically characterized by FTIR spectroscopy, X-ray diffraction, AFM and SEM analysis. The DSC thermal studies exhibit the transformations in the composites due to the effect of Bi(NO3)3. The mechanical strength, ac and dc conducting properties were studied. The variation of ac conductivity of the composites with frequency follows Jonscher’s universal power law and found to be increased with increasing temperature. The sample containing 10 wt% Bi(NO3)3 exhibits good mechanical strength, high conductivity and dielectric constant at room temperature. The variation of conducting properties of 10 wt% Bi(NO3)3 filled composite with temperature has been explained based on hopping mechanism. The frequency exponent (s) have been well fitted with the proposed correlation equation of the barrier hopping model. The transport parameters are estimated using Rice and Roth model. The activation energy is calculated for the sample PVA–LiClO4 matrix filled with 10 wt% Bi(NO3)3 using Arrhenius equation.