Recent work in the field of hydrogen storage and CO2 sequestration has been overwhelmingly dominated by the use of a narrow range of materials, specifically high surface area carbons (including carbon nanotubes) zeolites and metal hydrides. Activated carbons have the attraction that they are very cheap, their capacities on a weight % basis are very good due to their very low densities, and the adsorption process is readily reversible under mild conditions. Their shortcomings stem from the fact that the fundamental interactions between carbons and hydrogen are non-bonding in nature (i.e. they involve physisorption) and are therefore rather weak. Metal hydrides, adsorb hydrogen by a chemisorption process that is accompanied by dissociation of the dihydrogen molecules. The interaction is much stronger, but facile reversibility is a problem in many cases and such systems are often prone to irreversible poisoning by oxygen. There is clearly an urgent need to develop new classes of materials that have the potential to provide superior performance for hydrogen storage and CO2 sequestration. Some of the more recent developments in this area include the use of Metal Organic Frameworks (MOFs) and Covalent Organic Frameworks (COFs). Our strategy is aimed at the development of new materials systems where the host-guest interactions are intermediate between those found in the carbons and the metal hydrides.
|
Event calendar file
