High surface area carbon aerogels for supercapacitors

Applications of carbon aerogels as electrodes in supercapacitors require high surface area and simple production method. Carbon aerogels are derived via the pyrolysis of resorcinol-formaldehyde (RF) aerogels. In order to simplify production, subcritical drying of the RF gels is favoured, which is possible for gels prepared with high molar resorcinol to catalyst (R/C) ratios, i.e. very low catalyst concentrations. Resulting carbon aerogels consist of big microporous particles. The micropore surface area can account for more than 90% of the total surface area. The effect of thermal and chemical activation of such aerogels was investigated as a means to increase accessible surface and double-layer capacities. Aerogel structure was studied by small angle X-ray scattering (SAXS) and nitrogen - and CO2 - sorption. Accessibility of pores and aerogel performance as electrodes in supercapacitors was electrochemically investigated. (C) 1998 Elsevier Science B.V. All rights reserved.