Nano-sized Co/Co(OH)2 core-shell structure synthesized in molten salt as electrode materials for supercapacitors

A facile and low cost molten salt method for the synthesis of Co@Co(OH)(2) core-shell nanostructured material exhibiting high specific capacitances for supercapacitors was developed. In our conditions, the molten salt acted as solvent and reducing agent for the precipitation and formation of Co-based nano-structures. It was observed that in the Co@Co(OH)(2) core-shell nanostructure, Co cores can act as a conductive medium to improve the utilization of Co(OH)(2) due to the superior electrical conductivity of Co metal and its high surface area. It was also found that the as-prepared Co@Co(OH)(2) exhibited high electrochemical performance as a cathode material in asymmetric supercapacitors, yielding specific capacitance values of up to similar to 410 F g(-1) at 2 A g(-1) with a retention rate of 90 % after 2500 cycles. The achievement of high capacitance coupled to a low cost method represents an important step forward in the development of promising electrode materials for alkaline supercapacitor cathodes.