High-energy asymmetric electrochemical capacitors based on oxides functionalized hollow carbon fibers electrodes

Fe2O3 nanorod bundles and needle-like nickel-cobalt double hydroxide grown on hollow carbon fibers (aCF) are demonstrated as anode and cathode, respectively, for high-energy asymmetric supercapacitors (ASC). The high specific capacitance of both anode (988 F g−1) and cathode (1281 F g−1) enables the ASC device to deliver a maximum energy density of 83.7 Wh kg−1 at 392.3 W kg−1, while exhibiting remarkable cycling stability with 94.6% capacitance retention after 10000 cycles of continuous charge-discharge.286