Figure 5

(A) CV curves of the ZnCo2O4@CNT electrode at a scan rate of 0.5 mVs−1 between 0.01 V and 3.0 V. (B) Charge-discharge voltage profiles of the ZnCo2O4@CNT electrode at a current density of 400 mAg−1. (C) Rate capability of ZnCo2O4@CNT electrode at different current densities. (D) Comparison of cycling performance of ZnCo2O4@CNT (curve I), CNT (curve II) and pure ZnCo2O4 (curve III) at a current density of 400 mAg−1. Curve IV shows the corresponding coulombic efficiency of the ZnCo2O4@CNT electrode.