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

ABSTRACT 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 (SiO 2 ) viz. [PVC/PEMA–Zn(OTf) 2 –EMIMTFSI–SiO 2 ] exhibited the highest ionic conductivity value of 6.71 × 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 SiO 2 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 Zn 2+ ion conductivity. The NCGPE film possesses an electrochemical stability window up to 5.07 V (vs. Zn/Zn 2+ ) and ensures feasible zinc stripping/plating in the redox process. The addition of SiO 2 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 °C which were ascertained from Differential scanning calorimetry (DSC) and Thermogravimetric (TG) results. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47654.