Carbon aerogels with ultrathin, electroactive poly(o-methoxyaniline) coatings for high-performance electrochemical capacitors

Carbon aerogels are attractive electrode structures due to their high surface areas, through-connected porosity, and high electrical conductivity, as has been recognized by their commercialization for electrochemical capacitors. We extend the versatility of these conductive nanostructures by modifying them with ultrathin, electroactive polymer coatings based on the self-limiting electropolymerization of o-methoxyaniline. The pore–solid architecture is largely retained in the polymer–carbon-aerogel hybrid due to the conformal, self-limiting nature of the electrodeposited polymer coating. Although grown under insulating conditions, these polymers coatings become electroactive when exposed to aqueous-acid electrolytes, and contribute a pseudocapacitance component to the energy-storage mechanism in the hybrid nanoarchitecture. These hybrids and their electrochemical character can now be designed to exploit the functionalities of both the polymer and the carbon aerogel and achieve electrode structures that exhibit stability, high energy density, and high power density when used as electrochemical capacitors.