AC impedance studies on proton conducting biopolymer electrolytes based on pectin

Pectin based biopolymer electrolytes are prepared with different concentrations of ammonium thiocyanate by solution casting technique using distilled water as solvent. The amorphous nature and complexation of salt with polymer matrix are confirmed by X-ray diffraction (XRD) and Fourier transform infra-red spectrometer (FTIR) for all the prepared electrolytes. The cole-cole plot gives the maximum ionic conductivity of 4.05 × 10−6 S/cm for 0.08 g (20 mol%) of ammonium thiocyanate doped system. The number of the stoichiometrical charge carriers (n) in the 0.08 g salt doped system is 2.057 × 1021 cm−3 and it has maximum proton conduction as confirmed by transport number studies. The dielectric properties of the prepared proton conducting biopolymer electrolytes are also discussed in this work.