Effect of ionic liquid 1-ethyl-3-methylimidazolium hydrogen sulfate on zinc-ion dynamics in PEO/PVdF blend gel polymer electrolytes

Room temperature ionic liquid 1-ethyl-3-methylimidazolium hydrogen sulfate (EMIHSO4) incorporated gel polymer electrolyte membranes were prepared with PEO/PVdF blend containing 15wt % zinc triflate (Zn (CF3SO3)(2)) salt. These electrolyte membranes with different ionic liquid concentrations were characterized in detail by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), differencial scanning calorimetry (DSC) and electrical impedance spectroscopy (EIS). Amongst all the ionic liquid concentrations investigated, 10wt % EMIHSO4-incorporated gel electrolyte showed interesting electrochemical performance with the highest ionic conductivity of 5.8x10(-4)Scm(-1) at room temperature. Besides, ionic interactions of ethyl methylimidozolium cation (EMI+), ether oxygens of PEO and electronegative fluorine ions of PVdF with triflate anions and zinc cations at 10wt % EMIHSO4 tend to release more number of free ions. An impressive amount of amorphous phase also emerged with an addition of 10wt % EMIHSO4 by altering the semi-crystalline nature of PEO thereby facilitating rapid ion transport to occur.