Printer Friendly

Daylight robbery: Oxford University breakthrough could produce unlimited supplies of hydrogen using natural light.

TWO TEAMS OF researchers at Oxford University have brought the hydrogen revolution a step closer. One has found a way to generate a potentially unlimited source of hydrogen for fuel cells using only daylight. The other has developed a method of storing hydrogen at a high weight in a hydride that beats previous attempts to release the fuel at low temperatures.


Clean hydrogen generation is a key stumbling block for the realisation of the hydrogen economy and fuel cell use. Reforming fossil fuels can generate hydrogen, but the process produces greenhouse gas carbon as a by-product. Cleaner electrolysis methods can split water into hydrogen and oxygen and be powered by renewable energy, but power sources like solar cells are too expensive and need to improve their efficiency to generate enough electricity to force the reaction.

The Oxford University team placed transition metal nanoparticles inside a microporous oxide material that caused water to split into hydrogen and oxygen in ordinary daylight, without the need for an external electricity source like solar cells to drive the reaction.

Prof Peter Dobson, academic director of Begbroke Science Park at Oxford, said the research could lead to a 'radical breakthrough' in hydrogen generation that would be simpler and cheaper than coupling a renewable energy source with an electrolysis unit.

'In principle we could do the entire thing with a simple membrane separator, so in one half of the cell you generate oxygen, the other half hydrogen,' he said. 'It would stand unattended, bubbling off hydrogen and oxygen more or less forever until the catalyst is deactivated.'

The next step is to design a device that can separate the hydrogen and oxygen mix produced around the nanoparticles. 'We'll have to engineer the gas separation membranes very carefully. We may have to build in a potential gradient to separate the gases,' said Dobson.

'If we get the design right we may be able to incorporate catalysts into the membrane so it will run in an unattended fashion.'

Dr Tiancun Xiao, the Oxford inorganic chemist who made the discovery, is setting up a company called Oxford Catalysts to develop the technology.

Elsewhere at Oxford, a team led by Prof Peter Edwards has found a way of storing hydrogen at 8-9 weight per cent in a hydride that releases it again when subjected to temperatures of around 80[degrees]C. Hydrides can absorb hydrogen molecules into their structure and release them to power a fuel cell without the need for bulky and inefficient gas or liquid storage.

But previous high weight methods only worked at elevated temperatures of around 200[degrees]C or more (The Engineer, 14 January). The researchers have found a way to create the hydrides via a chemical route, rather than high-velocity ball milling.

COPYRIGHT 2005 U.S. Army Maneuver Support Center
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2005 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Author:Fisher, Richard
Publication:Engineer: The Professional Bulletin for Army Engineers
Geographic Code:1USA
Date:Mar 11, 2005
Previous Article:Gearing up for a Mars landing.
Next Article:Fuel for thought: project pulls together different strands of fuel cell R & D.

Related Articles
Tapping sun's light and heat to make hydrogen.
California drives the future of the automobile: impatience with fossil fuels is shaking California, which is the world's sixth-largest economy and...
Pioneer home for green fuel; ENVIRONMENT: Hydrogen project with no carbon emissions.
Bug enzyme can generate hydrogen from water.

Terms of use | Privacy policy | Copyright © 2022 Farlex, Inc. | Feedback | For webmasters |