Ref HAL: hal-00820095_v1
Exporter : BibTex | endNote
Résumé:

In recent years, a great emphasis has been placed on replacing fossil fuels with clean, renewable energy for use in vehicles. One potential solution is the use of hydrogen gas as a fuel source to power a fuel cell. For vehicular use, the US Department of Energy (DOE) has identified three major challenges to implementing a hydrogen-powered solution: (i) hydrogen production costs must be substantially lowered, (ii) a substantial reduction in fuel-cell costs, (iii) and hydrogen storage systems capable of delivering a driving range of hundreds of kilo-meters, without major detrimental effects to vehicle cost, safety, or cargo capacity must be developed. Mechanism of hydrogen adsorption in carbon porous structures is a fundamental problem for these applications. There exist many carbon porous structures which exhibit different capacities of adsorbed hydrogen, most of them too low for practical applications.It has shown that it is not possible to increase hydrogen storage capacity only by modification of slit geometry without simultaneous increase of the specific surface. So, we have introduced structures with higher surfaces and analyzed their adsorption properties. These new models of hypothetical structures represent activated carbons with low density architecture required for effective application of porous carbons for mobile storage. We call them Open Carbon Frameworks (OCF). Theoretically they may have the specific surfaces exceeding 6000 m2/g. From such perspective it is interesting to discuss the recent exceptional predictions of enhanced storage capacity of Covalent Organic Frameworks (COF) materials and Porous Aromatic Frameworks (PAF). The question arises: Is it possible to propose a porous carbon structure that will have properties required for hydrogen adsorption? Our discussion is focused on hypothetical model materials that have not been yet practically synthesized. It shows a vision and one possible way of searching for new porous carbon-based structures with properties required for storage applications.