Facile Synthesis of CoSe/Co3O4-CNTs/NF Composite Electrode for High-Performance Asymmetric Supercapacitor

Electrode materials are key factors for supercapacitors to endow them with excellent electrochemical properties. Here, a novel hybrid structure of a CoSe/Co3O4-CNTs binder free composite electrode on nickel foam was prepared via a facile flame method, followed by an electrodeposition process. Benefitting from the synergetic effects of the multicomponent (with low resistances of 1.542 Ω cm2 and a moderate mesoporous size of 3.12 nm) and the enlarged specific surface area of the composite material (77.4 m2 g−1), the CoSe/Co3O4-CNTs composite electrode delivers a high specific capacitance of 2906 F g−1 at 5 mV s−1 with an excellent rate stability. The fabricated CoSe/Co3O4-CNTs/NF//AC ASC exhibits a high energy density of 43.4 Wh kg−1 at 0.8 kW kg−1 and a long cycle life (92.7% capacitance retention after 10,000 cycles).