Hydrogen cat flap
19 Oct 2004
A team from the Universities of Liverpool and Newcastle upon Tyne in the UK have found a safe way of storing and releasing hydrogen to produce energy.
Hydrogen has been investigated for a long time as a potential future replacement for petrol, amid worries over the long-term availability of fossil fuels. It is also an environmentally friendly alternative, producing only water rather than the 'greenhouse gas' carbon dioxide. However, scientists and others have been baffled for a long time about how to store the substance - which is a gas and so contains less energy in a given volume than the liquid petrol - safely and efficiently.
Now, however, the Liverpool and Newcastle researchers have found a workable method of injecting the gas at high pressure into newly designed porous materials, to give a dense form of hydrogen, then reducing the pressure within the material in order to store the captured hydrogen safely.
Heat can then be applied to release the hydrogen as energy on which a car could potentially run.
'This is a proof of principle that we can trap hydrogen gas in a porous material and release it when required. However, if developed further, this method would have the potential to be applied to powering cars or any generator supplying power. Although hydrogen-powered cars are likely to be decades away, our discovery brings this concept a step towards becoming reality,' said Professor Mark Thomas from the University of Newcastle's School of Natural Science.
'Now that we have a mechanism that works, we can go on to design and build better porous framework materials for storing hydrogen, which may also be useful in industries that use gas separation techniques.'
'Our new porous materials can capture hydrogen gas within their channels, like a molecular cat-flap. After allowing the hydrogen molecule in, the structure closes shut behind it,' added Professor Matt Rosseinsky of the University of Liverpool's Department of Chemistry.
The important point is that the hydrogen is loaded into the materials at high pressure but stored in them at a much lower pressure - a unique behaviour. This basic science discovery may also have significant ramifications in other fileds of science that that rely on the controlled entrapment and release of small molecules.
