Accelerating proton-coupled electron transfer of metal hydrides in catalyst model reactions

Tianfei Liu, Meiyuan Guo, Andreas Orthaber, Reiner Lomoth, Marcus Lundberg, Sascha Ott, Leif Hammarström

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Metal hydrides are key intermediates in catalytic proton reduction and dihydrogen oxidation. There is currently much interest in appending proton relays near the metal centre to accelerate catalysis by proton-coupled electron transfer (PCET). However, the elementary PCET steps and the role of the proton relays are still poorly understood, and direct kinetic studies of these processes are scarce. Here, we report a series of tungsten hydride complexes as proxy catalysts, with covalently attached pyridyl groups as proton acceptors. The rate of their PCET reaction with external oxidants is increased by several orders of magnitude compared to that of the analogous systems with external pyridine on account of facilitated proton transfer. Moreover, the mechanism of the PCET reaction is altered by the appended bases. A unique feature is that the reaction can be tuned to follow three distinct PCET mechanisms—electron-first, proton-first or a concerted reaction—with very different sensitivities to oxidant and base strength. Such knowledge is crucial for rational improvements of solar fuel catalysts.

Original languageEnglish
Pages (from-to)881-887
Number of pages7
JournalNature Chemistry
Volume10
Issue number8
DOIs
Publication statusPublished - Aug 1 2018

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Hydrides
Protons
Metals
Catalysts
Electrons
Oxidants
Tungsten
Proton transfer
Pyridine
Catalysis
Oxidation
Kinetics

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)

Cite this

Accelerating proton-coupled electron transfer of metal hydrides in catalyst model reactions. / Liu, Tianfei; Guo, Meiyuan; Orthaber, Andreas; Lomoth, Reiner; Lundberg, Marcus; Ott, Sascha; Hammarström, Leif.

In: Nature Chemistry, Vol. 10, No. 8, 01.08.2018, p. 881-887.

Research output: Contribution to journalArticle

Liu, Tianfei ; Guo, Meiyuan ; Orthaber, Andreas ; Lomoth, Reiner ; Lundberg, Marcus ; Ott, Sascha ; Hammarström, Leif. / Accelerating proton-coupled electron transfer of metal hydrides in catalyst model reactions. In: Nature Chemistry. 2018 ; Vol. 10, No. 8. pp. 881-887.
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