Researchers are usually out to achieve perfection. But, it’s imperfection that is responsible for the latest, potential breakthrough in fuel cells.
Researchers from the Northwestern University and five other institutions have discovered that graphene with a few tiny holes in it could lead to better fuel cells.
To understand how graphene fits, you need to understand fuel cell technology. One of the biggest hurdles in fuel cell technology is separating protons from hydrogen. The researchers found single-layer graphene and water, with a few imperfections, transferred protons from one side of the graphene membrane to the other in seconds.
This could give engineers a new and much simpler mechanism for fuel cell design.
Chemist Franz M. Geiger, who led the research, explained the possible implications. “Imagine an electric car that charges in the same time it takes to fill a car with gas,” said Geiger. “And better yet – imagine an electric car that uses hydrogen as fuel, not fossil fuels or ethanol, and not electricity from the power grid, to charge a batter. Our surprising discovery provides an electrochemical mechanism that could make these things possible one day.”
How Does Imperfect Graphene Help?
Geiger and his colleagues noticed protons were moving through graphene that was exposed to water. They used modern imaging methods to see exactly how this happened.
I’ll let the press release explain.
The researchers discovered that naturally occurring defects in the graphene — where a carbon atom is missing — triggers a chemical merry-go-round where protons from water on one side of the membrane are shuttled to the other side in a few seconds. Their advanced computer simulations showed this occurs via a classic “bucket-line” mechanism first proposed in 1806.
It’s the thinness of the graphene sheet, just one atom thick, that makes this discovery potentially groundbreaking. Conventional membranes are usually hundreds of nanometers thick according to Geiger. The “merry-go-round” for protons would take minutes, not seconds.
But, how imperfect does the graphene need to be? The researchers found just a handful of carbon atoms need to be removed in a square micron area of graphene.
“Our results will not make a fuel cell tomorrow, but it provides a mechanism for engineers to design a proton separation membrane that is far less complicated than what people had thought before,” said Geiger. “All you need is slightly imperfect single-layer graphene.”
It might not change the world tomorrow, but if engineers can use this process for conventional fuel cells – the days of fossil fuels as a primary power source could be numbered.