“MIT researchers have made a discovery they claim will allow solar panels to make hydrogen and oxygen gas that can be stored and used to power a fuel cell when the sun is not out.”
From MIT’s Technology Review:
Researchers [Daniel Nocera and Matthew Kanan] have made a major advance in inorganic chemistry that could lead to a cheap way to store energy from the sun. In so doing, they have solved one of the key problems in making solar energy a dominant source of electricity.
Daniel Nocera, a professor of chemistry at MIT, has developed a catalyst that can generate oxygen from a glass of water by splitting water molecules. The reaction frees hydrogen ions to make hydrogen gas. The catalyst, which is easy and cheap to make, could be used to generate vast amounts of hydrogen using sunlight to power the reactions. The hydrogen can then be burned or run through a fuel cell to generate electricity whenever it’s needed, including when the sun isn’t shining.
The utilization of solar energy on a large scale requires its storage. In natural photosynthesis, energy from sunlight is used to rearrange the bonds of water to O2 and H2-equivalents. The realization of artificial systems that perform similar “water splitting” requires catalysts that produce O2 from water without the need for excessive driving potentials. Here, we report such a catalyst that forms upon the oxidative polarization of an inert indium tin oxide electrode in phosphate-buffered water containing Co2+. A variety of analytical techniques indicates the presence of phosphate in an approximate 1:2 ratio with cobalt in this material. The pH dependence of the catalytic activity also implicates HPO42â€“ as the proton acceptor in the O2-producing reaction. This catalyst not only forms in situ from earth-abundant materials but also operates in neutral water under ambient conditions.
Why this a big deal
- A major limitation of solar power is that solar cells produce peak power for only a few hours during the day.
- A major limitation to using hydrogen derived from water as fuel is how energy intensive hydrolysis is and the price and rarity of necessary catalysts.
- Nocera’s discovery uses cheap, earth abundant materials as a catalyst and offers a distributed way of storing solar energy for use at night.
Bonus: Nocera is making the technology open source.
“I’m open-sourcing this to let everybody run with it,” he said. “My plan is that when people see it, they’ll see it’s easy to do and they’ll start working it.”
via PCH and Frans J.