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 80.4Wh kg(-1) (275Wkg(-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. (c) 2018 Elsevier Ltd. All rights reserved.