Excerpt from rt.com

Scientists believe they can use the same material found in pencil to revolutionize the car industry. They discovered that graphene may serve as a fuel cell membrane and even allow the harvesting of hydrogen from air.
The reason the researchers at the of Manchester got so excited is that the fuel cells generate electricity from hydrogen. Graphene is known for its barrier qualities, and does not allow any other gases, hydrogen itself, or liquids to pass through it, which is crucial for the fuel cell

An even more exciting development is the of ‘sieving’ hydrogen from the air in future and using it to react with oxygen in a fuel cell, which could then produce electricity and water without leaving a carbon footprint. 

“Essentially you pump your fuel from the atmosphere and get electricity out of this fuel, in principle. Before this paper, this wouldn’t even be speculation; it would be science fiction. At least our paper provides a guidance and proof that this of device is possible and doesn’t contradict to any known laws of nature,” Andre Geim of Manchester University, who leads the study, said as cited by the Independent. 

“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 ,” said Marcelo Lozada-Hidalgo, co-researcher on the study. 

The has been published in the latest of Nature.