Vibrational and impedance spectroscopic study on PVP–NH4SCN based polymer electrolytes

Polymer electrolytes based on poly (N-vinyl pyrrolidone) (PVP) and ammonium thiocyanate (NH4SCN) prepared by solution cast technique have been studied using X-ray diffraction (XRD), Raman and impedance spectroscopic techniques. The XRD and Raman spectra for the electrolytes indicate that the amorphous nature of PVP increases with the increase of the concentration of ammonium thiocyanate. The spectral changes in the Raman bands of the CO and the CN stretching indicate the interaction between the salt and the polymer. The conductivity analysis shows that the 20 mol% ammonium thiocyanate doped polymer electrolyte exhibits high ionic conductivity and it has been found to be 1.7×10−4 S cm−1, at room temperature. The ionic coordination in the polymeric electrolytes, as determined by Raman spectroscopy, has been discussed in relation to the conductance behavior.