Cobalt Metallopeptide Electrocatalyst for the Selective Reduction of Nitrite to Ammonium


Guo Y., Stroka J. R. , Kandemir B., Dickerson C. E. , Bren K. L.

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, cilt.140, ss.16888-16892, 2018 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Cilt numarası: 140 Konu: 49
  • Basım Tarihi: 2018
  • Doi Numarası: 10.1021/jacs.8b09612
  • Dergi Adı: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
  • Sayfa Sayıları: ss.16888-16892

Özet

A cobalt-tripeptide complex (CoGGH) is developed as an electrocatalyst for the selective six-electron, eight-proton reduction of nitrite to ammonium in aqueous buffer near neutral pH. The onset potential for nitrite reduction occurs at -0.65 V vs Ag/AgCl (1 M KCl). Controlled potential electrolysis at -0.90 V generates ammonium with a faradaic efficiency of 90 +/- 3% and a turnover number of 3550 +/- 420 over 5.5 h. CoGGH also catalyzes the reduction of the proposed intermediates nitric oxide and hydroxylamine to ammonium. These results reveal that a simple metallopeptide is an active functional mimic of the complex enzymes cytochrome c nitrite reductase and siroheme-containing nitrite reductase.