Nickel foam supported hierarchical mesoporous MnO2/Ni(OH)2 nanosheet networks for high performance supercapacitor electrode

Abstract

In this paper, we report a high-performance MnO2/Ni(OH)2 nanosheets@nickel foam (MnO2/Ni(OH)2@NF) electrode material prepared by a facile one-step hydrothermal method. In this novel hierarchical design, nickel foam with a sheath of mesoporous Ni(OH)2 networks is coated with interconnected MnO2 nanosheets, which produces a highly porous reticular oxide/hydroxide/metal composite structure. The supercapacitor electrode made of the unique construction exhibits exceptional capacitance of 843.0Fg−1 at a charge/discharge current density of 1Ag−1 and superb rate capability (79.1% capacitance retention from 0.1 to 5Ag−1). The synergistic effects are employed to study the competitive advantages of MnO2/Ni(OH)2@NF electrode. Namely, 3D nickel foam serves as highly conductive backbone for deposition of nanostructured MnO2/Ni(OH)2 composite film, which provides the high accessibility of electrolytic ions for shorten diffusion paths.