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Remarkable stability of a molecular ruthenium complex in PEM water electrolysis.

ABSTRACT: The dinuclear Ru diazadiene olefin complex, [Ru₂(OTf)(μ-H)(Me₂dad)(dbcot)₂], is an active catalyst for hydrogen evolution in a Polymer Exchange Membrane (PEM) water electrolyser. When supported on high surface area carbon black and at 80 °C, [Ru₂(OTf)(μ-H)(Me₂dad)(dbcot)₂]@C evolves hydrogen at the cathode of a PEM electrolysis cell (400 mA cm^-2, 1.9 V). A remarkable turn over frequency (TOF) of 7800 mol_H₂ mol_catalyst ^-1 h^-1 is maintained over 7 days of operation. A series of model reactions in homogeneous media and in electrochemical half cells, combined with DFT calculations, are used to rationalize the hydrogen evolution mechanism promoted by [Ru₂(OTf)(μ-H)(Me₂dad)(dbcot)₂].

SUBMITTER: Bellini M

PROVIDER: S-EPMC8966732 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Remarkable stability of a molecular ruthenium complex in PEM water electrolysis.

Bellini Marco M Bösken Jonas J Wörle Michael M Thöny Debora D Gamboa-Carballo Juan José JJ Krumeich Frank F Bàrtoli Francesco F Miller Hamish A HA Poggini Lorenzo L Oberhauser Werner W Lavacchi Alessandro A Grützmacher Hansjörg H Vizza Francesco F

Chemical science 20220303 13

The dinuclear Ru diazadiene olefin complex, [Ru2(OTf)(μ-H)(Me2dad)(dbcot)2], is an active catalyst for hydrogen evolution in a Polymer Exchange Membrane (PEM) water electrolyser. When supported on high surface area carbon black and at 80 °C, [Ru2(OTf)(μ-H)(Me2dad)(dbcot)2]@C evolves hydrogen at the cathode of a PEM electrolysis cell (400 mA cm-2, 1.9 V). A remarkable turn over frequency (TOF) of 7800 molH2</su ...[more]

PMID: 35432912

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