Ion Transport and Spectroscopic Studies of Poly Acrylonitrile Complexed with Ammonium Trifluoro Methane Sulfonate (NH4CF3SO4) Gel Polymer Electrolyte SystemAuthor(s): Narasimharao Maragani, N. Krishna Jyothi and K. Vijaya Kumar
Ion transport property of poly acrylonitrile (PAN) complexed with ammonium trifluoro methane sulfonate (NH4CF3SO4) gel polymer electrolyte system is investigated with the aim of developing a high capacity solid state battery. The gel polymer electrolyte films have been prepared using dimethyl formamide (DMF) as solvent, ethylene carbonate (EC) as plasticizer, and ammonium trifluoro methane sulfonate (NH4CF3SO4) as salt with host polymer PAN by using solution cast technique. These films have been characterized by FTIR, UV-Visible spectroscopy and SEM. The change of conductivity with different wt% of salt concentrations ranging from 10 to 40 wt% is studied. The FTIR spectroscopic studies have confirmed that the complex formation between PAN and NH4CF3SO4. The absorption of pure and complexed electrolyte films have been studied in the visible and ultra-violet wavelength region and also observed that the new absorption peak was found at 290 and 375 nm, respectively. The surface morphology of different polymer electrolyte films has been explained by scanning electron microscopy (SEM). DC conductivity studies revealed that the increase in conductivity is due to increase of free ions. The conductivity - temperature studies of the gel polymer electrolyte films follow Arrhenius behavior with activation energy of ionic conduction are determined to be 0.09 eV to 0.26 eV. The maximum conductivity has been found to be 1.68 x 10-3 S cm-1 at room temperature (303K) and 3.46 x 10-3 S cm-1 at 378 K for 70:30 wt% films. The transport numbers both electronic (te) and ionic (ti) are evaluated using Wagner’s polarization technique. The ionic transport number of highest conducting film is found to be 0.992. It is revealed that the charge transport in these polymer electrolyte systems is predominantly due to ions.