Electrochemical performance evaluation of polyaniline nanofibers and polypyrrole nanotubes

Polypyrrole (PPy) nanotubes and polyaniline (Pani) nanofibers have been synthesized using chemical routes. The nanostructures are probed by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), field emission transmission electron microscope (FETEM) and Fourier transform infrared spectroscopy (FT-IR). The electrochemical performance of the nanostructures is determined by cyclic voltammetry (CV), galvanostatic charge–discharge and impedance measurements. The CV test has been performed using different electrolytes in order to get a superior electrode–electrolyte combination. The maximum specific capacitance for PPy nanotubes has been measured around 49.53F/g in 2 M KCl solution and that of 70F/g in 2 M H2SO4 solution in case of Pani nanofibers at a current density of 0.1 A/g. The higher specific capacitance of Pani nanofiber is attributed to its low charge transfer resistance as revealed from the Nyquist plot.