Manchester University (colours altered)

Graphene Could Be Used to Filter Fuel Out of Thin Air

Researchers have discovered that protons can pass through graphene - the world’s thinnest and strongest material. This means that it could one day be used to “sieve” hydrogen gas straight out of the atmosphere.

FIONA MACDONALD
28 NOV 2014
 

Scientists in the UK have found that graphene isn’t just incredibly strong and light - it also allows protons, or positively charged hydrogen atoms, to pass through it. 

This means that in the future it could be used to build fuel cells that generate electricity from nothing but the hydrogen in the atmosphere.

 

"We are very excited about this result because it opens a whole new area of promising applications for graphene in clean energy harvesting and hydrogen-based technologies," the co-author of the study, Marcelo Lozada-Hidalgo of Manchester University, told Reuters.

The team was led by Andre Geim - the scientist who was involved in first isolating graphene back in 2004 - and their discovery is just one of many revolutionary property displayed by the material. 

First of all, graphene is just one-carbon-atom thick, making it one of the thinnest and lightest materials on Earth, and it’s also 200 times stronger than steel, flexible and highly conductive.

It’s also impermeable to gasses and liquids, and even the smallest of atoms.

But in the new study, the researchers decided to test whether it also repelled protons - hydrogen atoms that had been stripped of all their electrons.

Surprisingly, they found that the protons could pass through the material quite easily, especially when the temperatures were raised and the graphene was coated in nanoparticles, such as platinum, which acted as a catalyst. Their results are published in Nature.

This means that graphene could one day be used to build more efficient fuel cells by being incorporated into proton-conducting membranes - crucial elements of fuel cell technology.

Fuel cells are devices that trigger a reaction of oxygen and hydrogen fuel, and convert chemical energy into electricity with only water as a byproduct.

These are already used in some electric cars, but currently they’re not as efficient as they need to be to replace fossil fuels.

The major issue is that the fuels leaks across the existing proton membranes, effectively poisoning the process and making the fuel cell less effective - something that the researchers have now shown could be overcome by using impermeable graphene.

Even more excitingly, the researchers found that the graphene membrane could actually be used to extract hydrogen straight from the atmosphere, which means it could be used to create mobile electric generators that are power by nothing more than hydrogen in air.

"Essentially, you pump your fuel from the atmosphere and get electricity out of it," Geim told Reuters. "Our [study] provides proof that this kind of device is possible."

Obviously the research is in its very early stages, and we still need to learn more about how protons pass through graphene. It's also not clear exactly how much electricity could be generated out of the tiny amounts of hydrogen that are present in the atmosphere. But it’s a fascinating discovery that could change the way we harvest electricity, and that’s pretty damn exciting.

Source: Reuters via ABC Science

More From ScienceAlert