Electrical conductivity and dielectric properties of solid polymer nanocomposite films: Effect of BaTiO3 nanofiller

Abstract

Polymer nanocomposite comprising of PEO-PVC + LiClO4 with BaTiO3 as nanofiller were synthesized by the solution cast technique. The dispersion of the nanofiller in the polymer matrix promotes fast ion migration. Impedance study reveals that the ionic conductivity is enhanced by the addition of BaTiO3 and the maximum value is 2.35 × 10−5 S cm−1 for 3 wt. % BaTiO3 attributed to favorable conductive path formation for cation. The ion transference number is close to unity and the voltage stability window is of the order of 3.5 V. The complex dielectric permittivity, dielectric loss, complex conductivity, was studied and fitted with the corresponding established expression in the entire frequency range (1–100 kHz). The dielectric constant increases with the addition of the nanofiller and is attributed to the complete salt dissociation. The ac conductivity analysis displays a shift of dispersion region toward high frequency which is attributed to the faster ion migration and also evidenced by lowering of relaxation time. It has been noticed that the relevant parameters like ionic conductivity, ion transference number, voltage stability and the dielectric parameters are dependent on the content of nano-sized BaTiO3 filler content. A systematic ion transport mechanism has been proposed to highlight the role of nanofiller in enhancing the desired parameters.