Figure 8. Electrochemical impedance spectroscopy of reassembled δ-MnO2 electrodes.
(a) Nyquist plots of the samples in the frequency range of 0.1 Hz–100 kHz at an open circuit potential of 5 mV (inset shows the electrical equivalent circuit used for fitting the impedance spectra); and (b) comparison of the charge transfer resistance among the three samples (values obtained from the fitted data).