Preparation of graphene aerogel and its electrochemical properties as the electrode materials for supercapacitors

Graphene oxide was prepared through an improved method, and then three-dimensional graphene aerogel was (GA) synthesized by an organic sol-gel process. The morphological characteristics and textural properties of the GA were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectrum (FT-IR), respectively. For capacitive properties tests, cyclic voltammetry (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS) were carried out in a two-electrode system with a working potential window from 0 to 1V. Moreover, a specific capacitance of 176 F/g was determined at a constant current density of 1 A/g in 1 mol L⁻¹ Na2SO4 electrolyte. The advantageous properties such as high specific surface areas, high specific capacitance, high conductivity and well-connected 3D mesoporous structure of the GA, permit excellent performance as electrode materials for supercapacitors.