Synthesis and characterization of proton-conducting polymer electrolyte based on polyacrylonitrile (PAN)

Solid polymer electrolytes based on polyacrylonitrile (PAN) doped with ammonium iodide (NH4I) have been prepared by solution casting method with different molar ratios of polymer and salt using DMF as solvent. The XRD pattern confirms the dissociation of salt. The FTIR analysis confirms the complex formation between the polymer and the salt. A shift in glass transition temperature (T-g ) of the PAN/NH4I electrolytes has been observed from the DSC thermograms, which indicates the interaction between the polymer and the salt. The conductivity analysis shows that the polymer electrolyte with 20 mol% NH4I has the highest conductivity equal to 1.106 x 10(-3) S cm(-1) at room temperature. The activation energy (E-a ) has been found to be low for the highest conductivity sample. The dielectric permittivity (epsilon*) and modulus (M*) have been calculated from the alternating current (AC) impedance spectroscopy in the frequency range 42 Hz-1 MHz. The DC polarization measurement shows that the conductivity is mainly due to ions.