Fig. 3
Electrochemical performance of MnO2/rGO and conventional MnO2 electrodes. a Cyclic voltammogram of the MnO2/rGO and conventional MnO2 electrodes at a scan rate of 0.2 mV s-1 in 1.0–1.9 V vs. Zn2+/Zn. b Comparison of the charging and discharging profiles of the samples at the current density of 0.3 A g-1. c Specific capacities (normalized over the mass of MnO2) of the samples at various current density. Inset in Fig. c: comparison of the specific capacity retention of the samples. d Nyquist plots of the samples after charging to ~1.9 V vs. Zn2+/Zn. e Cycling stability of the samples (MnO2/rGO and conventional MnO2 electrodes) cycled at 6.0 A g-1 and corresponding Coulombic efficiency of MnO2/rGO electrode. f A summary graph of the specific capacity (based on the total mass of the whole electrode material, including MnO2, additive and binder) of our MnO2/rGO electrode and other reported MnO2-based electrodes for ZIB at different current densities
