Fuel cells extract energy from fuel chemically rather than burning it, which in general is more efficient and produces less pollution than combustion engines that burn fuel.
Hydrocarbons like fossil fuels and plant matter are widely used as fuel in fuel cells, but they produce carbon monoxide as a waste product. Carbon monoxide is usually removed using the water-gas shift reaction which requires fuel cells to contain heating and cooling equipment and a supply of water.
Researchers from the University of Wisconsin at Madison have found a way to use the carbon monoxide to produce more energy in a reaction that can take place at room temperature.
The method could eventually be used in portable systems that use renewable fuel produced from plant matter; the process could also be used to treat wastewater and contaminated gas streams, according to the researchers.
The researchers added a chemical reactor to the fuel cell that uses a membrane made from gold nanotubes as a catalyst in a reaction that converts carbon monoxide and liquid water to carbon dioxide, hydrogen ions and electrons.