Abstract
Hydrogen production through water splitting is one of the most promising solutions for the storage of renewable energy. [NiFe] hydrogenases are organometallic enzymes containing nickel and iron centres that catalyse hydrogen evolution with performances that rival those of platinum. These enzymes provide inspiration for the design of new molecular catalysts that do not require precious metals. However, all heterodinuclear NiFe models reported so far do not reproduce the Ni-centred reactivity found at the active site of [NiFe] hydrogenases. Here, we report a structural and functional NiFe mimic that displays reactivity at the Ni site. This is shown by the detection of two catalytic intermediates that reproduce structural and electronic features of the Ni-L and Ni-R states of the enzyme during catalytic turnover. Under electrocatalytic conditions, this mimic displays high rates for H2 evolution (second-order rate constant of 2.5 × 104 M−1 s−1; turnover frequency of 250 s−1 at 10 mM H+ concentration) from mildly acidic solutions.
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Acknowledgements
Financial support for this work was provided by Labex arcane (ANR-11-LABX-003), the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement no. 306398 and the COST Action CM1305 (EcostBio) including an STSM grant (COST-STSM-CM1305- 26539) to D.B.
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C.D. and V.A. conceived and designed the project. D.B. carried out the experimental work under the supervision of M.G. T.R.S. contributed to the synthetic work. J.P. performed X-ray analysis. F.M. and S.D. performed and analysed the Mössbauer experiments. N.Q. contributed to the analysis of the electrochemical data. M.O. carried out the theoretical calculations. C.D., V.A. and M.G. analysed and interpreted the experimental data and prepared the manuscript. All authors reviewed and contributed to the manuscript.
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Brazzolotto, D., Gennari, M., Queyriaux, N. et al. Nickel-centred proton reduction catalysis in a model of [NiFe] hydrogenase. Nature Chem 8, 1054–1060 (2016). https://doi.org/10.1038/nchem.2575
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DOI: https://doi.org/10.1038/nchem.2575
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