KYUDAI NEWS KYUSHU UNIVERSITY CAMPUS MAGAZINE Spring 2013 No.24

15/32

Future ProspectsIt is expected that this research achievement will help advance technology using hydrogen energy in the future, for example, in the development of platinum-free fuel cells. It will also give synthetic chemists the ability to precisely control reactions that use the hydrogen molecule as an important building block.PublicationTitle : A Functional [NiFe]Hydrogenase Mimic That Catalyzes Electron and Hydride Transfer from H2 Authors : Seiji Ogo, Koji Ichikawa, Takahiro Kishima, Takahiro Matsumoto, Hidetaka Nakai, Katsuhiro Kusaka, Takashi OhharaJournal : ScienceDOI : 10.1126.science.1231345*1 Nickel-iron hydrogenase : This is a naturally occurring enzyme that activates hydrogen gas. The active site has a binuclear structure of nickel (Ni) and iron (Fe) bridged by a sulfur atom (S) of cysteine residue (Cys), as is shown in Fig. 1. X indicates H2O, OH– or O2– in a resting state, and it also indicates H– in an activated state.Glossary and Notes*2 Nickel-ruthenium catalyst : This is an artificial model catalyst of a nickel-iron hydrogenase, which was developed by the research group headed by Prof. Ogo of Kyushu University in 2007. (Fig. 2) This artificial model catalyst contains ruthenium (Ru) instead of iron (Fe), and activates hydrogen gas at room temperature and atmospheric pressure. (Published in Science 315, 585-587, 2007, Press release on April 25, 2007)*3 Nickel-iron catalyst : This is an artificial model catalyst of nickel-iron hydrogenase, which has now been developed by the research group headed by Prof. Ogo of Kyushu University (published in Science 339, 682-684, 2013, Press release on February 6, 2013). Like the nickel-iron hydrogenase that naturally occurs in nature, it activates hydrogen gas using nickel (Ni) and iron (Fe) at room temperature and atmospheric pressure. The group revealed the structure of the artificial model catalyst using X-ray and neutron diffraction. (Fig.3)*4 Extraction of electrons from hydrogen gas at room temperature and atmospheric pressure : Specifically, this refers to a catalytic cycle as shown in Fig. 4. Catalyst 1 activates hydrogen gas, and then forms catalyst 2, where iron (Fe) is combined with hydride ion (H–). Catalyst 2 provides electrons to electron acceptors and then returns to catalyst 1.14Kyudai News No.24 Get Energy from Hydrogen Developed by ChemistsA Cheaper Way to Get Energy from HydrogenFig.1 Active site structure of nickel-iron hydrogenases (Cys = cysteine residue)Fig.2 Structure of the nickel-ruthenium catalystFig.3 X-ray structure of the nickel-iron catalystFig.4 Electron extraction from hydrogen gas with the nickel-iron catalysts

※このページを正しく表示するにはFlashPlayer9以上が必要です