MnO2/graphene/nickel foam composite as high performance supercapacitor electrode via a facile electrochemical deposition strategy

A novel MnO2/graphene (G)/nickel foam (NF) composite as supercapacitor electrode was fabricated by a facile electrochemical deposition approach for the first time. The approach includes electrophoretic deposition of G on NF (EPD-G/NF) and electrodeposition of MnO2 on EPD-G/NF (MnO2/EPD-G/NF). Compared with other methods for preparing MnO2/G composite, our green strategy avoids using harsh chemicals (e.g. hydrazine) or high temperature treatment for reducing graphene oxide. Owing to unique structure, specific capacitance (C-s) of the MnO2/EPD-G/NF electrode is as high as 476 F g(-1) at high current density of 1 A g(-1) in 0.5 M Na2SO4 solution, which is the highest C-s for MnO2/G composites to date, and the C-s is higher than that of MnO2/NF electrode. Furthermore, it also exhibits high rate capacity, such as 216 F g(-1) of C-s at 10 A g(-1). On the other hand, our strategy provides a versatile method for fabrication of other G-based composites with metal oxide/hydroxide or conducting polymer as supercapacitor electrode. (C) 2012 Elsevier B.V. All rights reserved.