Multidimensional design of a cathode electrode composed of a nickel-cobalt carbonate hydroxide and nitrogen-doped pyridine toward high-performance supercapacitors

초록

A three-dimensional (3D) porous NiCo(CO3)(OH)(2) nanowire composite was fabricated by a facile hydrothermal method and directly grown on a nitrogen-doped, pyridine-based mesoporous carbon substrate to serve as cathode electrode for a supercapacitor. The microscopic structure of this well-organized, independent, nanoscale electrode material exhibited a high electrical conductivity and good ion transportability. The optimized NiCo(CO3) (OH)(2) composite had a remarkably high specific capacitance of 320.2 mAh g(-1) at a current density of 3 Ag-1 and excellent cycling stability (84.5 %) maintained after 5000 cycles at a current density of 10 A g(-1). An asymmetric supercapacitor fabricated using the optimized NiCo(CO3)(OH)(2) composite as the positive electrode and graphene as the negative electrode produced a high energy density of 41.1 W h kg(-1) and excellent power density of approximately 201.2 W h kg(-1) at a current density of 2 A g(-1). As a result, this asymmetric supercapacitor was able to power a light-emitting diode. These results suggest that the NiCo(CO3)(OH)(2) composite on the pyridinebased substrate is a promising candidate for commercial energy storage devices toward the fabrication of highperformance supercapacitors.

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