Amorphous MnO2 supported on 3D-Ni nanodendrites for large areal capacitance supercapacitors

In this paper, we report a metal oxide/metal MnO2/3D dendrites-like Ni core-shell electrode on Ni foam for high-performance supercapacitors. The MnO2/3D-Ni electrode exhibits a large areal capacitance (837.6 mF cm(-2)) at high loading mass of MnO2(3 mg cm(-2)). Moreover, MnO2/3D-Ni composite electrodes exhibit excellent rate capability and high cycling stability (16% degradation after 2000 cycles). The high electrochemical properties of MnO2/3D-Ni electrode can be attributed to the high conductivity of the Ni metal core, high porous and large specific surface structure of the MnO2/3D-Ni nanocomposites, which facilitates electrolyte diffusion, electron transport, and material utilization. These results indicate highly conductive 3D dendrites-like Ni nanoparticles may could provide new opportunities for the development of high performance supercapacitors. (C) 2014 Elsevier Ltd. All rights reserved.