Carbon aerogels modified with graphene oxide, graphene and CNT as symetric supercapacitor electrodes

Abstract

Highly porous carbon aerogels with carbon structures additives may be attractive materials for energy storage devices. Traditional resorcinol–formaldehyde-based carbon aerogels modified with graphene, graphene oxide and CNT were compared with respect to their morphology and capacitive properties as electric double layer capacitors. Materials were prepared using drying in supercritical acetone instead of commonly used carbon dioxide. Acetone was not only used for solvent exchange but was also expelled medium at supercritical conditions. This allowed to limit materials shrinkage and enhance specific capacity that in case of CNT-modified carbon aerogel was as high as 326 F/g i.e. more than 4 times bigger than for parent carbon aerogel. The specific surface area increased from 123 to 629 m2/g. Enhancement of the specific capacity was also found for gels modified with graphene and graphene oxide. The reason of such a behavior was a difference in structure and pore size distribution of additives.