ABSTRACT The molecular apparatus behind biological photosynthesis retains its long-term functionality through enzymatic repair. However, bioinspired molecular devices designed for artificial

photosynthesis, consisting of a photocentre, a bridging ligand and a catalytic centre, can become unstable and break down when their individual modules are structurally compromised, halting

their overall functionality and operation. Here we report the active repair of such an artificial photosynthetic molecular device, leading to complete recovery of catalytic activity. We

have identified the hydrogenation of the bridging ligand, which inhibits the light-driven electron transfer between the photocentre and catalytic centre, as the deactivation mechanism. As a

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Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS DUAL DONOR-ACCEPTOR COVALENT ORGANIC FRAMEWORKS FOR HYDROGEN PEROXIDE PHOTOSYNTHESIS Article Open access 28 August 2023 A

PHOTOSENSITIZER–POLYOXOMETALATE DYAD THAT ENABLES THE DECOUPLING OF LIGHT AND DARK REACTIONS FOR DELAYED ON-DEMAND SOLAR HYDROGEN PRODUCTION Article 27 January 2022 HYDROGEN-BONDED ORGANIC

FRAMEWORKS FOR PHOTOCATALYTIC SYNTHESIS OF HYDROGEN PEROXIDE Article Open access 12 March 2025 DATA AVAILABILITY Source data are provided with this paper and can also be found via Zenodo

(https://doi.org/10.5281/zenodo.5565021). All other data supporting the findings of this study are available within the paper and its Supplementary Information files. REFERENCES * Acar, C.,

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  Google Scholar  Download references ACKNOWLEDGEMENTS We thank the German Science Foundation for funding via the TRR 234 CataLight (project number 364549901; project A1, C.M., B.D.-I. and

S.R.; project B4, M.W.; project C5, P.S., S.K. and S.G), the Fonds der Chemischen Industrie (Kekulé-Stipendium, C.M.) and the Studienstiftung des Deutschen Volkes (PhD scholarship, B.B.). We

acknowledge the developers of the KiMoPack software employed for global lifetime analysis of the time-resolved spectra. All calculations were performed at the Universitätsrechenzentrum

(Friedrich Schiller University Jena, P.S., S.K. and S.G.). The funding organizations had no role in study design, data collection and analysis, decision to publish or preparation of the

manuscript. AUTHOR INFORMATION Author notes * These authors contributed equally: Michael G. Pfeffer, Carolin Müller. AUTHORS AND AFFILIATIONS * Institute of Inorganic Chemistry I (Materials

and Catalysis), Ulm University, Ulm, Germany Michael G. Pfeffer, Evelyn T. E. Kastl, Alexander K. Mengele, Benedikt Bagemihl, Sven S. Fauth, Johannes Habermehl, Lydia Petermann & Sven

Rau * Institute of Physical Chemistry, Friedrich Schiller University Jena, Jena, Germany Carolin Müller, Martin Schulz, Phillip Seeber, Stephan Kupfer, Stefanie Gräfe & Benjamin

Dietzek-Ivanšić * Leibniz Institute of Photonic Technology, Jena, Germany Carolin Müller, Maria Wächtler & Benjamin Dietzek-Ivanšić * Abbe Center of Photonics, Jena, Germany Maria

Wächtler * Department of Chemistry, University of Montréal, Montréal, Québec, Canada Daniel Chartrand, François Laverdière & Garry S. Hanan * SRC for Solar Energy Conversion, School of

Chemical Sciences, Dublin City University, Dublin, Ireland Johannes G. Vos * Center for Energy and Environmental Chemistry Jena, Friedrich Schiller University Jena, Jena, Germany Benjamin

Dietzek-Ivanšić Authors * Michael G. Pfeffer View author publications You can also search for this author inPubMed Google Scholar * Carolin Müller View author publications You can also

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Vos View author publications You can also search for this author inPubMed Google Scholar * Benjamin Dietzek-Ivanšić View author publications You can also search for this author inPubMed 

Google Scholar * Sven Rau View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS M.G.P., E.T.E.K. and D.C. performed the catalysis experiments,

C.M. performed the steady-state and time-dependent in situ spectroscopic studies, and M.S. and M.W. synthesized and investigated the hydrogenated photocatalyst. M.G.P., A.K.M., B.B., S.F.,

J.H., D.C., F.L., G.S.H. and S.R. developed the active repair strategies. P.S., S.K. and S.G. conducted the quantum chemical simulations. M.G.P, C.M., L.P., G.S.H., J.G.V., A.K.M., B.D.-I.

and S.R. wrote the manuscript with help from all the other authors. CORRESPONDING AUTHORS Correspondence to Benjamin Dietzek-Ivanšić or Sven Rau. ETHICS DECLARATIONS COMPETING INTERESTS The

authors declare no competing interests. PEER REVIEW PEER REVIEW INFORMATION _Nature Chemistry_ thanks Ken Sakai, Claudia Turro and the other, anonymous, reviewer(s) for their contribution to

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SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Supplementary Figs. 1–27, Tables 1–4, Discussion and Experimental Details. SOURCE DATA SOURCE DATA FIG. 1 Hydrogen turnover numbers and

chemical structures. SOURCE DATA FIG. 2 In situ absorption data and chemical structures. SOURCE DATA FIG. 3 In situ absorption and ultrafast transient absorption data, hydrogen turnover

numbers (mean, s.d., _n_ = 3) and peak area ratios. SOURCE DATA FIG. 4 Absorption data. SOURCE DATA FIG. 5 Hydrogen turnover numbers and chemical structures. RIGHTS AND PERMISSIONS Reprints

and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Pfeffer, M.G., Müller, C., Kastl, E.T.E. _et al._ Active repair of a dinuclear photocatalyst for visible-light-driven hydrogen

production. _Nat. Chem._ 14, 500–506 (2022). https://doi.org/10.1038/s41557-021-00860-6 Download citation * Received: 20 August 2020 * Accepted: 19 November 2021 * Published: 07 February

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