Optimization of salt concentration and Explanation of Two Peak Percolation in Blend Solid Polymer Nanocomposite Films.

The present paper report is focused toward the preparation of the flexible and freestanding blend solid polymer electrolyte films based on PEO-PVP complexed with NaPF6 by solution cast technique. The structural/morphological features of the synthesized polymer nanocomposite films have been investigated in detail using X-ray diffraction, Fourier transform infra-red spectroscopy, field emission scanning electron microscope, and atomic force microscopy techniques. The film PEO-PVP+NaPF6 O/Na:8 exhibits highest ionic conductivity ~5.92x10-6 S cm-1 at 40 oC and ~2.46x10-4 S cm-1 at 100 oC. The temperature dependent conductivity shows Arrhenius type behavior and activation energy decreases with the addition of salt. The high temperature (100 oC) conductivity monitoring is done for the optimized PEO-PVP+NaPF6 O/Na:8 highly conductive system and the conductivity is still maintained stable up to 160 h (approx. 7 days). The thermal transitions parameters were measured by the differential scanning calorimetry (DSC) measurements. The prepared polymer electrolyte film displays the smoother surface in addition of salt and a thermal stability up to 300 oC