What the MOF are Metal Organic Frameworks?!


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Happy New Year!

The team here at Linkam is always interested to know how our stages are influencing scientific research around the world.  In studies such as the one below, it is exciting to know we are playing a part in the breakthrough of a potential source of renewable energy.

Metal-Organic Frameworks (MOFs) are very promising new materials that may be valuable in an almost endless number of different applications. They are crystalline compounds consisting of Metal Ions which are co-ordinated to Organic Molecules to form structures that have a good level of porosity.

These MOFs are already known to have many uses, such as in drug delivery and other biological applications, but currently, their main use is as gas storage molecules for hydrogen, carbon dioxide,  polar vapors and various other substituted aromatics.

It is the hydrogen storage capabilities of these frameworks that have caught the eye of budding researchers all over the globe as they strive to speed up the development of non-petroleum based energy carriers such as fuel cells. Hydrogen gas in particular seems like a highly viable option because of its high energy content in comparison to gasoline and also the fact that its by-products are not as damaging to our environment.

MOFs are highly suited to for the purpose of Hydrogen storage as they have a very high surface area to absorb the molecular hydrogen. So for example, you can dramatically increase the hydrogen storage capabilities of an empty gas cylinder just by lining it with a layer of MOFs.  The hydrogen molecules are taken up by the MOFs, but there is not much of an activity energy, in the form of heat, required to liberate them again.

With the increased investment into the search for more renewable energy sources, many academic groups have focused their research into finding more flexible and useful frameworks.  One group in particular, headed by Herve Leclerc from the Universite de Caen Basse-Normandie, France, looked into the effects changing the oxidation state of a particular MOF (in this case MIL47) has on its Hydrogen absorption properties.

The group used the Linkam CCR1000 stage coupled to a raman spectrometer to see what effect the alteration of the oxidation number of MIL47 had on the change in activation energy required for liberation of the Hydrogen adsorbed in the framework.

The interesting results of their experimentations can be found here.

Posted by Ricky Patel