The primary objective of this EPSRC project, which runs through 2009, is to prepare novel PIMs in a form that demonstrate hydrogen loadings equal to or in excess of the IEA 5% benchmark for hydrogen storage on-board vehicles at moderate pressures and 77 K (-196.2°C).

Most polymers pack space efficiently and are thus not microporous, thereby making them unsuitable for hydrogen storage. Professor Neil McKeown at Cardiff has focused on developing polymers of intrinsic microporosity (PIMs) that do possess significant microporosity.

PIMs feature a highly rigid and contorted structure that does not pack space efficiently. This creates interconnected molecular-sized holes (i.e. micropores) that can be used for storing hydrogen. Other potential applications include use as catalyst supports, gas separation membranes and as adsorbents to remove toxic pollutants from water.

The chemical composition of PIMs can be tailored via synthetic chemistry for the specific needs of an application.

We are excited to report this recent discovery by our research team of a polymer which can hold around three per cent hydrogen by weight. Although we still have a long way to go, it is clear that we are moving in the right direction, especially as we also have a number of promising new polymers to test.

—Professor McKeown

Professor McKeown and his team are investigating a number of promising methods to enhance porosity as they attempt to build on their current success and produce a material that can store and release hydrogen safely and effectively. They are also collaborating with Professor Kenneth Harris within the School of Chemistry to develop other types of hydrogen storage materials.