Details

Autor(en) / Beteiligte

• HELM, Monte L
• STEWART, Michael P
• BULLOCK, R. Morris
• DUBOIS, M. Rakowski
• DUBOIS, Daniel L

Titel

A Synthetic Nickel Electrocatalyst with a Turnover Frequency Above 100,000 s―1 for H2 Production

Ist Teil von

• Science (American Association for the Advancement of Science), 2011-08, Vol.333 (6044), p.863-866

Ort / Verlag

Washington, DC: American Association for the Advancement of Science

Erscheinungsjahr

2011

Quelle

American Association for the Advancement of Science

Beschreibungen/Notizen

• 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.