High-performance, lightweight supercapacitors
doi:10.1038/nindia.2015.34 Published online 18 March 2015
Researchers have fabricated novel electrodes by using core–shell hybrid nanostructures made from nickel, iron and the oxides of both metals1. These electrodes can be used to produce supercapacitors that can store large electrical charges, making them potentially useful for use in lightweight electronic fuses, backup power systems and camera flashes.
To produce supercapacitors with high power densities, the researchers synthesized porous, core–shell hybrid nanostructures consisting of nickel, iron and the oxides of both metals. The hybrid nanostructures consist of approximately 25-nanometre-thick shells that homogeneously coat the surfaces of core nanowires, which are made of nickel and iron and have diameters of around 100 nanometres.
The researchers made the supercapacitor electrode from these core–shell hybrid nanostructures and found them stable on a long-term. The supercapacitor retained nearly 95% of its initial capacitance after 3,000 cycles of charging and discharging. “In addition, it showed low resistance, indicating its high electrical conductivity and a rapid ion-charge transport during electrochemical reactions at the contact of electrode and electrolyte,” says co-author Ashutosh Singh.
1. Singh, A. K. et al. Engineering of high performance supercapacitor electrode based on Fe-Ni/Fe2O3-NiO core/shell hybrid nanostructures. J. Appl. Phys. 117, 105101 (2015)