Ni(OH)2 nanosheet @ Fe2O3 nanowire hybrid composite arrays for high-performance supercapacitor electrodes

We demonstrate the design and fabrication of novel hybrid nanoarchitectures using facile coating of ultrathin Ni(OH)(2) nanosheets onto alpha-Fe2O3 nanowire arrays directly grown on Fe foils toward achieving high specific capacitance, high-energy and high power density, and long-term life supercapacitors. Well structured single-crystalline alpha-Fe2O3 nanowires uniquely served as cores that support redox active high surface area Ni(OH)(2) shells and also contribute to specific capacitance as a conventional pseudocapacitive metal oxide. The Ni(OH)(2)@alpha-Fe2O3 hybrid composites exhibited excellent rate capability with specific energy of 22.8 Wh/kg and specific power of 16.4 kW/kg at a current density of 54.6 A/g, and excellent long-term cycling stability (keep over 85.7% of the initial specific capacitance after 5000 cycles). These results suggest that such hybrid composite architectures are very promising for the next generation of highperformance supercapacitors. (C) 2013 Elsevier Ltd. All rights reserved.