Reduced Graphene Oxide Embedded V2O5 Nanorods and Porous Honey Carbon as High Performance Electrodes for Hybrid Sodium-ion Supercapacitors

Attaining high energy density and power density in a single energy storage device is still a major challenge for electrochemical energy storage research community. Sodium-ion hybrid supercapacitor is a sustainable energy storage system which accomplishes the gap between battery and supercapacitor comprises of high energy density-battery type faradaic anode and high power density-supercapacitor type non-faradaic cathode. Here we have reported high surface area (1554 m(2) g (1)) activated porous carbon obtained from naturally occurring viscous liquid honey as a cathode and sol-gel derived, V2O5 nanorods anchored reduced graphene oxide (rGO) nanocomposite as an anode for non-aqueous sodiumion capacitor. When explored honey derived carbon as a non-faradaic cathode, it exhibits a higher specific capacitance of 224 F g (1) and V2O5@rGO anode delivers the maximum capacitance of 289 F g (1) at 0.01 A g (1) vs Na/Na+. The prepared V2O5@rGO anode has long stable cycle life (V2O5 nanorods@rGO retains 85% of the initial capacitance (112.2 F g (1)) at the current density of 0.06 A g (1) after 1000 cycles). The assembled sodium-ion capacitor (NIC) using honey derived activated carbon (AC) and V2O5@rGO anode delivers the energy density of approximate to 65 Wh kg (1) and power density of approximate to 72 W kg (1) at 0.03 A g (1). The capacity retention is 74% after 1000 cycles at the current density of 0.06 Ag (1). The assembled sodium-ion hybrid capacitor delivers maximum energy and power density and exhibits very long stable cycle life. (C) 2017 Elsevier Ltd. All rights reserved.