Enhancement in electrical and stability properties of amorphous polymer based nanocomposite electrolyte

A novel combination of dispersed phase polymer nanocomposite electrolyte (PNCE) series based on an amorphous polymer host (PMMA)4–LiClO4 complex dispersed with nanocrystalline CeO2 is reported. XRD analysis has confirmed the dispersed phase nanocomposite formation. Effect of nano CeO2 dispersion on ion–ion and ion–polymer interactions has been analyzed. A drastic enhancement in electrical conductivity, by 2 orders of magnitude at 30 °C and 5 orders of magnitude at 100 °C, has occurred on nano CeO2 dispersion when compared with room temperature conductivity of undispersed PS film. An excellent correlation between variation of d.c. conductivity and free mobile charge carriers has been observed. An ion conduction model is proposed. Strength of the model lies in the experimental evidences from FTIR, conductivity and TEM analyses. Thermal analysis indicates a strong dependence of thermodynamical parameters, e.g., glass transition temperature (Tg), crystalline melting temperature (Tm), enthalpy etc. on filler addition. Substantial improvement in voltage stability (~ 4.4 V), thermal stability and ion transport properties has been noticed on nano CeO2 dispersion.

► Dispersed phase nanocomposite formation is confirmed from the XRD analysis.
► Polymer-ion, ion-ion and polymer-ion-filler interactions are probed through FTIR analysis.
► Electrical conductivity improves by ~ 2 orders of magnitude at 30 °C and ~ 5 orders of magnitude at 100 °C on n-CeO2 dispersion.
► Ionic transport number for all PNCE films is ≥ 99%. Voltage stability and thermal stability improve with addition of filler.
► An ion conduction mechanism is proposed to explain filler concentration dependent conductivity variation in the PNCE films.