Tomorrow’s hydrogen energy economy has come a large step closer. A Manchester University research team, led by Nobel physicist Andrei Geim, has demonstrated a process that pulls hydrogen fuel out of thin air.
The secret: graphene, a one-atom-thick lattice of carbon atoms. Graphene is thought to be the world’s best barrier, having proven impenetrable by every kind of liquid and gas. Geim’s team has discovered the one exception: protons – hydrogen atoms stripped of their electrons – which easily slip in between the graphene’s carbon atoms. The particles move even more easily under higher temperatures and when the graphene is coated with a catalyst such as platinum.
The scientists created the same effect using a one-atom-thick sheet of boron nitride, a material similar to graphene.
Graphene’s impenetrability has made it an ideal barrier for use in applications such as waterproof packaging. Now Manchester’s researchers have shown that it also can be used as a sieve to strain protons from air using an electric current, gather them on the far side of a graphene barrier, and then siphoned into a fuel cell to make electricity or heat.
Until now, designers of hydrogen-powered fuel cells had no simple, cost-effective way to purify hydrogen for fuel; contaminants inevitably invaded, degrading the cells’ performance and longevity. Geim’s group has shown a way to filter hydrogen protons into a fuel chamber that can be made to contain nothing else.
Because graphene already can be manufactured in square-meter sheets, the researchers see their discovery making its way into commercial fuel cells sooner rather than later.