Carbon black directed synthesis of ultrahigh mesoporous carbon aerogels

Abstract

A simple modification of the conventional sol–gel polymerization of resorcinol–formaldehyde mixtures allowed a facile preparation of ultrahigh mesoporous carbon gels. In the conventional synthesis the growth of the cluster polymer particles leading to the development of the porosity is controlled by the R/C ratio. In the presence of a carbon conductive additive, the polymerization of the reactants proceeded through the formation of less-branched polymer clusters resulting in carbon gels with large pore volumes within the micro/mesoporous range. The obtained materials displayed unusual heterogeneous pore systems characterized by large mesopores interconnected by necks of variable sizes, along with an enhanced electrical conductivity provided by the carbon black additive. The gels showed stable electrochemical response in neutral aqueous electrolyte, being reversibly charged/discharged at large potential windows, without significant losses in the current density, chemical modifications or structural collapse. The enhanced life cycle of these electrodes makes them good candidates for their use in electrochemical applications where a fast response and high cycleability is required.