'Unzipped' carbon nanotubes

'Unzipped' carbon nanotubes could help energize fuel cells and metal-air batteries,

Stanford scientists say
Platinum catalysts in fuel cells are too expensive for large-scale production.

... Stanford scientists have developed a technique that could make carbon nanotubes an attractive, low-cost alternative.

This drawing shows the damaged outer wall of a carbon nanotube with nanosized graphene pieces (white patches), which facilitate the formation of catalytic sites made of iron (yellow) and nitrogen (red) atoms. The catalyst reduces oxygen to water. (Image: Guosong Hong / Stanford University)
Fuel cells use chemicals to create electricity. They are used, for example, to keep the lights on for astronauts in orbiting space stations. They hold promise in a variety of areas, such as fuel-cell cars. But the high price of catalysts used inside the cells has provided a roadblock to widespread use.
Now, nanoscale research at Stanford University has found a way to reduce the cost.
Multi-walled carbon nanotubes riddled with defects and impurities on the outside could eventually replace some of the expensive platinum catalysts used in fuel cells and metal-air batteries, according to Stanford scientists.