Facile preparation of the novel structured α-MnO2/Graphene nanocomposites and their electrochemical properties

Graphene-based materials are promising electrodes for supercapacitors, owing to their unique two-dimensional structure, high specific surface area, and good electrical conductivity. In this paper, alpha-MnO2/Graphene composite materials with a unique 1D/2D hierarchical structure have been successfully prepared via a facile hydrothermal route. The morphology and structure of as-obtained products are systematically studied by X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and N-2 adsorption/desorption measurement. The electrochemical properties are investigated by cyclic voltammetry and galvanostatic charge discharge. Finally, it is shown that the introduction of 1D alpha-MnO2 nanofibers could keep the space between the neighboring graphene sheets and prevent the aggregation and/or restacking of graphene, thus enhancing the effective surface area and electrochemical properties of the hybrid materials. Crown Copyright (C) 2013 Published by Elsevier Masson SAS. All rights reserved.