Researchers at Case Western Reserve University in Cleveland say catalysts made of carbon nanotubes dipped in a polymer solution can outperform traditional platinum catalysts in fuel cells at a fraction of the cost.
The scientists say the new technology can remove one of the biggest roadblocks to widespread cell use: the cost of the catalysts.
Platinum, which represents at least a quarter of the cost of fuel cells, currently sells for about $30,000 per pound, while the activated carbon nanotubes cost about $45 per pound, a Case release said Tuesday.
"This is a breakthrough," Liming Dai, a professor of chemical engineering and the research team leader, said.
Soaking carbon nanotubes in a water solution of the polymer for a couple of hours coats the nanotube surface and pulls an electron partially from the carbon, creating a net positive charge, researchers said.
When placed on the cathode of an alkaline fuel cell, the charged material acts as a catalyst for the oxygen-reduction reaction that produces electricity by electrochemically combining hydrogen and oxygen.
In testing, the researchers' carbon catalyst fuel cell produced as much power as an identical cell using a platinum catalyst.
Dai said he's confident his lab can increase the energy output of the new process.
"We have not optimized the system yet," he said.
One widely researched use for such cells would be to produce electricity to power an electric car, using hydrogen and oxygen from the air. The only emission from such a vehicle, researchers say, would be water.