According to principal investigator Anthony Kucernak, the price of platinum in the catalyst currently determines about 60% of the cost of each fuel cell. This makes the cells very expensive for large-scale use in hydrogen cars, for example.
In the innovative catalyst, the iron atoms are dispersed in an electrically conductive carbon matrix, rather than in clusters. Because of the dispersion, the iron stimulates the reactions in the fuel cell. In laboratory tests, the one-atom iron catalyst was shown to have performance comparable to that of platinum-based catalysts in a commercial fuel cell system.
The method the team developed to make catalysts (called transmetallation) could also be adapted for other processes, such as chemical reactions using atmospheric oxygen as a reactant instead of expensive chemical oxidants, and in wastewater treatment using air to remove harmful pollutants.
The new catalyst has been tested in collaboration with UK fuel cell catalyst manufacturer Johnson Matthey. Scale-up is now necessary to allow its use in commercial fuel cells.
The results were published in Nature Catalysis.
Image: Imperial College London