Chemical science news from across RSC Publishing.
Energy from model enzymes
12 August 2008
Mimicking enzymes with inorganic complexes could offer a new route to catalysing hydrogen fuel cells, claim Japanese scientists.
In nature, hydrogenases are enzymes that catalyse the splitting of hydrogen in its H2 form into two separate protons and two electrons. However, there has been some controversy over the mechanism by which the enzyme operates, with mechanistic studies contradicting experimental data. Now, a group led by Seiji Ogo at Kyushu University, Fukuoka, have solved this problem by making a nickel-ruthenium complex that acts as a model of the enzyme. They say this complex could be used to develop new cathode catalysts for hydrogen fuel cells.
The complex is water-soluble like natural hydrogenases, and so allows the first study of a model in the hydrogenases' natural environment. |
Described by Chris Pickett, an energy expert from University of East Anglia, Norwich, UK, as 'an elegant chemical precedent', the complex is water-soluble like natural hydrogenases, and so allows the first study of a model in the hydrogenases' natural environment.
Ogo explains that that understanding the exact mechanism of the hydrogenase will allow scientists to progress research into new types of catalysts for hydrogen fuel cells. The group studied how the complex reacts and showed that the generation of single and double exchange products is simultaneous, just as observed for the naturally occurring enzymes. Ogo is now looking forward to further studies on this model that should uncover more details of the reaction.
Water soluble organometallics like these have become more and more interesting for both life and materials sciences. Ogo hopes that technology for the extraction of electrons from hydrogen, using his new complexes can now be developed.
Laura Howes
Link to journal article
pH-Dependent isotope exchange and hydrogenation catalysed by water-soluble NiRu complexes as functional models for [NiFe]hydrogenases
Bunsho Kure, Takahiro Matsumoto, Koji Ichikawa, Shunichi Fukuzumi, Yoshiki Higuchi, Tatsuhiko Yagi and Seiji Ogo, Dalton Trans., 2008, 4747
DOI: 10.1039/b807555g
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