The structure of graphene is a flat hexagonal grid of carbon atoms. This grid can act as an extremely fine filter, which allows (small) hydrogen molecules to pass through, but which captures larger molecules of pollutants. UCL's Prof Xiao Guo leads a £1m project to develop prototype fuel filters for fuel-cell electric vehicles based on this technology. Improved purity of hydrogen fuel could double the lifespan of these vehicles' expensive power sources.
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