α-Fe2O3/rGO nanospindles as electrode materials for supercapacitors with long cycle life

Abstract Spindle-like α-Fe2O3 and reduced graphene (rGO) composites have been synthesized by a simple hydrothermal method. The synthesized samples exhibit excellent electrochemical performance with high specific capacitance and good cycling life of about 87.5% reserved after 10,000 cycles. A solid-state asymmetric supercapacitor (ASC) with 1.5 V Voltage has been assembled using α-Fe2O3/rGO composite anode and the NiCo2O4 nanowires cathode. The ASCs exhibit outstanding capacitance performance with maximum energy density of 73 Wh kg−1 at the power density of 1357 W kg−1, and more than 219% capacitance retention after 10,000 cycles.