Scientists led by Vincent Artero at Joseph Fourier University in Grenoble, France, have mimicked natural hydrogenase enzymes to catalyze the electrolysis of water into hydrogen and oxygen. Unlike conventional methods that rely on platinum or other precious metal catalysts, enzyme-based elecrolysis is potentially very inexpensive. The catalyst revolves around a nickel bisdiphosphine core. Similiar to natural hydrogenases, a nickel atom is ligated between two diphosphine groups which facilitate proton movement. However, unlike natural systems, these biomimetic catalysts are bound to the exterior of a carbon nanotube which is used to conduct electrons for the reaction. A polymer substrate keeps acids from entering the catalytic region and interfering with the reaction; this mimicks the functionality of carbohydrate polymers in natural systems. Although currently only capable of producing low yields, this biomimetic technique is quite stable and efficient. According to Dan DuBois, the inventor of the basic design, "They're actually functioning quite nicely, and I think that if we can get another one or two orders of magnitude in rate, which is doable, then they will be useful." The process could be useful for the industrial production of hydrogen for fuel cells.
The bioinspired catalyst will be based on protein-like cores. These are easily produced. Platinum is extremely expensive and requires harmful mining and recycling processes to aquire.
Although matching the output of platinum-based catalysts with biomimetic ones will take some time to accomplish, it is likely possible. Moreover, the materials required to produce industrial-scale electrolysis equipment using the biomimetic technique will be extremely inexpensive compared to precious metals.Edit Summary