Silicon strip developed at MIT might be key to inexpensive fuel cells

The thumb-size black strip looks like a thin magnet. But in reality, it is an artificial leaf, made of silicon and capable of using sunlight to split water into hydrogen and oxygen that can be fed into fuel cells to make power.

“You drop it in a glass of water and you walk outside and hold it in the sun, and you’ll start to see bubbles of hydrogen and oxygen,’’ explained Daniel Nocera, an MIT professor who led the team that invented the device.


The next step, he said, is to make the technology work on a large scale to produce enough hydrogen and oxygen for a fuel cell to power a car or home.

The leaf, which Nocera has worked on for about three years, has the potential to solve one of the most pressing challenges facing solar power: how to store energy produced by the sun so it can be used on cloudy day. Instead of a battery, that energy could be stored as oxygen and hydrogen gases, then recombined in fuel cells, which generate electricity from the chemical reaction.