Turning Dirty Air into Clean Energy

By Kevin Ritchart

Scientists from the University of Antwerp and the University of Leuven in Belgium created a device that both purifies air and converts it into energy.

The device consists of two chambers separated by a membrane. Polluted air is purified on one side of the membrane, and stored as hydrogen gas — a byproduct of the degradation process — on the other. The hydrogen gas can be used as fuel at a later time.

“Our device is unique because it’s an all-in-one system, which uses air as a source of water and directly produces hydrogen gas,” said Johan Martens of the KU Leuven Centre for Surface Chemistry and Catalysis. “The system is also carbon neutral, and there is no net use of water. The device gets the water it needs from the air and releases it back into the air again. In theory, this device could even be used in the desert, because there, too, every cubic meter of air contains about five grams of water.”

Stepping on the (Hydrogen) Gas

Some hydrogen buses already utilize this type of technology. Hydrogen fuel cells convert hydrogen into energy that powers the bus. They can be recharged quickly and run for a long period of time. The exhaust from hydrogen buses is water rather than greenhouse gases.

Specific nanomaterials are used to construct the membrane, which spans just a few square centimeters. Researchers are hoping to increase the size of the device as they continue to refine the design. The technology being employed to convert the purified air into energy is similar to the functionality of solar panels. The difference between the two is that the Belgian device doesn’t produce energy directly, but rather stores it for future use.

Slowing the Effects of Climate Change

According to Martens, producing hydrogen gas through the use of this device could help in the fight against climate change.

“We live in a carbon world: there’s no getting around that,” Martens said. “We shouldn’t ban carbon emission from our economy. Instead, we can collect the CO₂ that is produced and recycle it to obtain new fuel or usable chemicals. By adding hydrogen gas to CO₂ you can, for instance, produce synthetic natural gas.”

While it’s more difficult to reduce the carbon footprint of households, vehicles and other large-scale, industrial ventures, this method of producing hydrogen gas should prove useful in combatting climate change once more data is collected.