Synthesis, characterization, and modeling of hydrogen storage in carbon aerogels

摘要

Carbon aerogels are a special class of open-cell foams with an ultrafine cell/pore size (<50 nm), high surface area (600-800 m(sup 2)/g), and a solid matrix composed of interconnected colloidal-like particles or fibers with characteristic diameters of 10 nm. These materials are usually synthesized from the sol-gel polymerization of resorcinol-formaldehyde or phenolic-furfural, followed by supercritical extraction of the solvent and pyrolysis in an inert atmosphere. The resultant aerogel has a nanocrystalline structure with micropores (<2 nm diameter) located within the solid matrix. Carbon aerogel monoliths can be prepared at densities ranging from 0.05-1.0 g/cm(sup 3), leading to volumetric surface areas (> 500 m(sup 2)/cm(sup 3)) that are much larger than commercially available materials. This research program is directed at optimization of the aerogel structure for maximum hydrogen adsorption over a wide range of temperatures and pressures. Computer modeling of hydrogen adsorption at carbon surfaces was also examined.