Fuel cells could decode how life arose on Earth

Ever wondered how life arose from the toxic and inhospitable environment of our planet billions of years ago? Fuel cells may have the answer!
A new NASA study used fuel for testing chemical reactions thought to have led to the development of life on Earth.
"Something about Earth led to life, and we think one important factor was that the planet provides electrical energy at the seafloor," said Laurie Barge from Jet Propulsion Laboratory in Pasadena, California, who led the study.
"This energy could have kick-started life - and could have sustained life after it arose. Now, we have a way of testing different materials and environments that could have helped life arise not just on Earth, but possibly on Mars, Europa and other places in the solar system," said Barge.

Fuel cells are similar to biological cells in that electrons are also transferred to and from molecules. In both cases, this results in electricity and power, researchers said.
In order for a fuel cell to work, it needs fuel, such as hydrogen gas, along with electrodes and catalysts, which help transfer the electrons.

Electrons are transferred from an electron donor (such as hydrogen) to an electron acceptor (such as oxygen), resulting in current.
In cells, metal-containing enzymes - biological catalysts - transfer electrons and generate energy for life.
In the team's experiments, the fuel cell electrodes and catalysts are made of primitive geological material thought to have existed on early Earth.

By testing different types of materials, these fuel cell experiments allow the scientists to narrow in on the chemistry that might have taken place when life first arose on Earth.
"What we are proposing here is to simulate energetic processes, which could bridge the gap between the geological processes of the early Earth and the emergence of biological life on this planet," said Terry Kee from the University of Leeds, England, one of the co-authors of the research paper.
"We're going back in time to test specific minerals such as those containing iron and nickel, which would have been common on the early Earth and could have led to biological metabolism," Barge added.

The study appears in the journal Astrobiology.