Hierarchical\nMesoporous Zinc–Nickel–Cobalt\nTernary Oxide Nanowire Arrays on Nickel Foam as High-Performance Electrodes\nfor Supercapacitors

Abstract

Nickel foam supported hierarchical\nmesoporous Zn–Ni–Co\nternary oxide (ZNCO) nanowire arrays are synthesized by a simple two-step\napproach including a hydrothermal method and subsequent calcination\nprocess and directly utilized for supercapacitive investigation for\nthe first time. The nickel foam supported hierarchical mesoporous\nZNCO nanowire arrays possess an ultrahigh specific capacitance value\nof 2481.8 F g^–1 at 1 A g^–1 and\nexcellent rate capability of about 91.9% capacitance retention at\n5 A g^–1. More importantly, an asymmetric supercapacitor\nwith a high energy density (35.6 Wh kg^–1) and remarkable\ncycle stability performance (94% capacitance retention over 3000 cycles)\nis assembled successfully by employing the ZNCO electrode as positive\nelectrode and activated carbon as negative electrode. The remarkable\nelectrochemical behaviors demonstrate that the nickel foam supported\nhierarchical mesoporous ZNCO nanowire array electrodes are highly\ndesirable for application as advanced supercapacitor electrodes.