Effect of propylene carbonate as a plasticizer on (PEO)50AgCF3SO3:SnO2 nanocomposite polymer electrolyte

This work deals with the incorporation of propylene carbonate (PC) as a plasticizer in conjunction with poly (ethylene oxide) (PEO), silver triflate (AgCF3SO3) and nanocrystalline tin oxide (SnO2) for obtaining the nanocomposite polymer electrolyte system (PEO)(50)AgCF3SO3:2 wt% SnO2 + x wt% PC (x = 10, 20, 30 and 40) by solution casting method. The present electrical conductivity data extracted by means of complex impedance spectroscopic analysis in the frequency range 20 Hz-1 MHz and over the temperature domain 298-373 K have demonstrated that the maximum electrical conductivity value of 5.9 x 10(-5) S cm(-1) at 298 K would be possessed by the specimen containing 30 wt% PC incorporated into the optimized nanocomposite system (PEO)(50)AgCF3SO3:2 wt% SnO2. Silver ionic transference number (t(Ag)+) data evaluated using AC/DC polarization technique have indicated that the highest tAg? value of 0.52 could be realized in the case of the specimen (PEO)(50)AgCF3SO3:2 wt% SnO2 + 30 wt% PC, whereas the complexation of the plasticizer within the nanocomposite electrolyte has been deduced from the detailed Fourier transform infrared spectroscopic investigation owing to the fact that such results have revealed the appearance of absorption bands corresponding to free triflate ions (CF3SO3-) and PC. Surface morphological features of pure PEO and (PEO)(50)AgCF3SO3:2 wt% SnO2 + 30 wt% PC nanocomposite systems were analysed through scanning electron microscope. The feasibility of a reduction in the degree of crystallinity of the plasticized system has been indicated by the X-ray diffraction data and confirmed from differential scanning calorimetric results obtained in terms of quantification of crystallinity and reduction in the glass transition temperature due to the addition of the chosen plasticizer into the nanocomposite polymer electrolyte matrix. Interestingly, the all solid-state cell based on the nanocomposite polymer electrolyte, namely, (PEO)(50)AgCF3 SO3:2 wt% SnO2 + 30 wt% PC and silver anode has exhibited an open circuit voltage of 676 mV and short circuit current of 192 mu A at room temperature.