Conductive Fe@Fe2O3/FeOOH necklace-like nanowires of high electrochemical performances for a supercapacitor application

Abstract With the development of iron-based supercapacitor materials, iron-based composites are the developing trend of iron-based supercapacitor. Iron coated with Iron-based oxide (Fe@Fe 2O3 /FeOOH) nanowires was synthetized from the natural surface oxidation of nanomaterials with high surface energy. The Fe@Fe 2O3 /FeOOH composite revealed a promising negative material with a high specific capacitance of 1186 F/g (1423 C/g) at a current density of 1 A/g and 820 F/g (820 C/g) at a scan speed of 1 mV/s in a three-electrode system. The amount of residual capacitance calculated from cyclic voltammetry (CV) measurement after 2000 cycles at 1 A/g is as much as 80% of that at the first few cycles which indicate an active particle has a distinct adsorption and desorption process. The excellent pseudocapacitance of the Fe@Fe 2O3/FeOOH nanowires electrode could be a briefness method for a hierarchical electrode material. The maximum pseudocapacitance of a supercapacitor at the current density of 1 A/g is 184 F/g (276 C/g), which the energy density is 57.5 Wh/kg and the power density is 750 W/kg, accordingly in a device.