Scientists at the University of New South Wales have developed a highly efficient oxygen-producing electrode for splitting water to produce hydrogen. The process has the potential to be scaled up for the industrial production of the clean energy fuel.
Hydrogen has great potential for storing electricity and as a fuel but the majority of hydrogen is currently produced using fossils fuels, such as natural gas, because this is cheaper than electrolysis of water.
Inefficient and costly oxygen-producing electrodes are one of the major barriers to reducing the cost of the commercial production of hydrogen by electrolysis.
Unlike other water electrolysers that use precious metals as catalysts, the new electrode is made entirely from two inexpensive and abundant metals – nickel and iron.
Commercially available nickel foam, which has holes about 200 micrometres wide in it, is electroplated with an ultra thin, highly active nickel-iron catalyst. This catalyst reduces the amount of electricity needed for the water-splitting to occur. The layer of a nickel-iron also has tiny pores, about 50 nanometres across, in it. The three-dimensional architecture of the electrode means that it has an enormous surface area on which the reaction can occur.
Associate Professor Chuan Zhao, who led the research, said that “I think this electrode has great potential for the industrial-scale production of hydrogen. Our next goal is to understand the science behind it and to further improve its performance. Cleaner sources of fuel like hydrogen will be particularly important for reducing carbon dioxide emissions and solving the air pollution problems from the burning of fossil fuels such as coal.”