Researchers from the University of Massachusetts, Amherst have recently engineered Geobacter metallireducens, a bacterium that can feed with hydrogen and carbon dioxide to produce electricity.
“This represents the first result of current production solely on hydrogen,” says Amit Kumar, who worked with Derek Lovely, the scientist who first isolated Geobacter metallireducens 26 years ago, in the Potomac River.
Geobacter species are of interest because of their bioremediation, bioenergy potential, novel electron transfer capabilities, the ability to transfer electrons outside the cell and transport these electrons over long distances via conductive filaments known as microbial nanowires.
By studying a relative of Geobacter metallireducens called Geobacter sulfurreducens, Kumar and the team produced electricity by having the bacteria reduce organic carbon compounds with a graphite electrode like iron oxide or gold to serve as the only electron receptor. The bacteria they chose for engineering did not have the need for carbon to grow in a microbial fuel cell.
Kumar also notes that when the hydrogen supply to the fuel cell was interrupted, the cell’s electricity production dropped significantly.
Hydrogen has already been known for its energy-carrying properties, and electricity has been so far generated by using expensive and complex hydrogen fuel cells, that contained platinum. By using readily-available carbon as a constituent of a fuel cell, the perspective of a hydrogen-powered future looks a bit closer.
