Structure and electrochemical properties of carbon aerogels synthesized at ambient temperatures as supercapacitors

In this paper, the carbon aerogels derived from organic sol-gel process were prepared by means of ambient drying technique. Morphology and physical properties of the carbon aerogels were characterized by scanning electron microscopy (SEM) and N-2 sorption isotherm. It was found that the carbon aerogels were porous materials with pearly network structure, the particle size of carbon aerogels increased with the increase of R/C ratio (molar ratio of resorcinol to catalyst). The BET surface areas of obtained carbon aerogels were in the range 600-1000 m(2)/g. Electrochemical performances of the carbon acrogels electrodes were studied by cyclic voltammetry, galvanostatic charge/discharge measurements and electrochemical impedance measurement. The results indicated that carbon aerogels electrodes had good electrochemical performance, high reversibility and high specific capacitance. Moreover, the utilization efficiency of carbon aerogels was promoted due to excellent electronic conductivity and extensive mesoporous network of carbon aerogels. The specific capacitance of the electrode is 183.6 F/g with R/C ratio 1500. In addition, the carbon aerogel electrode for the application of supercapacitor had low resistance, small leakage current and good electrical conductivity. (c) 2007 Elsevier B.V. All rights reserved.