Publication Date:
2011-08-13
Description:
Reduction of acids to molecular hydrogen as a means of storing energy is catalyzed by platinum, but its low abundance and high cost are problematic. Precisely controlled delivery of protons is critical in hydrogenase enzymes in nature that catalyze hydrogen (H(2)) production using earth-abundant metals (iron and nickel). Here, we report that a synthetic nickel complex, [Ni(P(Ph)(2)N(Ph))(2)](BF(4))(2), (P(Ph)(2)N(Ph) = 1,3,6-triphenyl-1-aza-3,6-diphosphacycloheptane), catalyzes the production of H(2) using protonated dimethylformamide as the proton source, with turnover frequencies of 33,000 per second (s(-1)) in dry acetonitrile and 106,000 s(-1) in the presence of 1.2 M of water, at a potential of -1.13 volt (versus the ferrocenium/ferrocene couple). The mechanistic implications of these remarkably fast catalysts point to a key role of pendant amines that function as proton relays.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Helm, Monte L -- Stewart, Michael P -- Bullock, R Morris -- DuBois, M Rakowski -- DuBois, Daniel L -- New York, N.Y. -- Science. 2011 Aug 12;333(6044):863-6. doi: 10.1126/science.1205864.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Center for Molecular Electrocatalysis, Chemical and Materials Sciences Division, Pacific Northwest National Laboratory, Post Office Box 999, K2-57, Richland, WA 99352, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21836012" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
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Chemistry and Pharmacology
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Computer Science
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Medicine
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Natural Sciences in General
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Physics
