Investigation on electrochemical behavior of rGO nanosheet supported cobalt doped vanadium pentoxide nanorods as a battery type asymmetric capacitor device

Metal oxide combined with carbon-based materials are attractive for supercapacitor applications due to their high stability and their attractive faradaic redox reaction mechanism. Herein, we demonstrated the rod-shaped Co doped V2O5 wrapped with rGO nanosheets for supercapacitor application. The supercapacitor application was carried out using three and two electrode testing methods. The gravimetric capacity values are 233.88 mAh g−1, 120.83 mAh g−1 and 86.66 mAh g−1 for the Co:V2O5@rGO, Co:V2O5 and V2O5 electrodes at 1 A/g. Furthermore, the Co:V2O5@rGO electrode exhibits 96 % capacity retention after the 1000 cycles. However, the fabricated Co:V2O5@rGO//rGO asymmetric capacitor device electrode was working at 1.2 V and it showed the specific capacity value of 72.22 mAh g−1 at 2 A/g. Also, the electrode shows energy density value of 43.33 Wh/kg and power density value of 1200 W/kg. The cyclic retention of the Co:V2O5@rGO//rGO ACs electrode was 94.89 % between the starting and 2000th cycles. Moreover, the ACs devices show a low Rct value of 6.57 Ω. Based on the results, the Co:V2O5@rGO electrode is a potential electrode for supercapacitor applications.