Zinc ion conducting blended polymer electrolytes based on room temperature ionic liquid and ceramic filler

Zinc ion conducting nanocomposite gel polymer electrolytes (NCGPEs) comprising of poly(vinyl chloride) (PVC)/poly(ethyl methacrylate) (PEMA) blend, zinc triflate [Zn(OTf)(2)] salt, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIMTFSI) ionic liquid (IL) and fumed silica (SiO2) viz. [PVC/PEMA-Zn(OTf)(2)-EMIMTFSI-SiO2] exhibited the highest ionic conductivity value of 6.71 x 10(-4) Scm(-1) at room temperature. The ion-filler-polymer interactions and probable conformational changes observed in the structure of the gel composites due to the entrapment of IL and dispersion of nano-sized SiO2 were confirmed from X-ray diffraction (XRD) and Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. Scanning electron microscopic (SEM) images of NCGPEs demonstrated uniform surface with abundant interconnected micropores. The cationic transport number of NCGPE samples has been found to be appreciably enhanced up to a maximum of 0.69 thus demonstrating a considerable improvement in Zn2+ ion conductivity. The NCGPE film possesses an electrochemical stability window up to 5.07 V (vs. Zn/Zn2+) and ensures feasible zinc stripping/plating in the redox process. The addition of SiO2 into the gel polymer electrolyte system has effectively reduced the glass-transition temperature (T-g) of the NCGPE films and also accomplished improved thermal stability up to approximately 180 degrees C which were ascertained from Differential scanning calorimetry (DSC) and Thermogravimetric (TG) results. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47654.