Graphene / V2O5 hybrid electrode for an asymmetric supercapacitor with high energy density in an organic electrolyte

A novel rGO/V₂O₅ hybrid aerogel composite made up of vanadium pentoxide nanospheres embedded in graphene sheets was synthesized by an easy hydrothermal method. V₂O₅ with a loading of only 12 wt% in composite played a significant pseudocapacitance role. To obtain better material, an annealing process in a tube furnace was used. The final rGO/V₂O₅ electrode showed excellent electrochemical performance, achieving a specific capacitance of 384 F g^-1 at 0.1 A g⁻¹ and of 197 F g^-1 at 2 A g⁻¹. The rGO/V₂O₅ functioned as the anode and graphene functioned as the cathode in an asymmetric supercapacitor used in an organic electrolyte resulted in a wide potential operating window of 2.5 V and delivered a maximum energy density of 80.4 Wh kg⁻¹ (275 W kg⁻¹) at 0.2 A g⁻¹. In addition, the device possessed acceptable cyclic stability, with only 17.8% loss after 10000 cycles at 2 A g⁻¹. All of these outstanding properties could make the electrode material prepared in this study a promising application material for supercapacitors.