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 means of repair, we used the light-driven generation of singlet oxygen, catalysed by the photocentre, to enable the oxidative dehydrogenation of the bridging unit, which leads to the restoration of photocatalytic hydrogen formation.
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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.
The authors declare no competing interests.
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Hydrogen turnover numbers and chemical structures.
In situ absorption data and chemical structures.
In situ absorption and ultrafast transient absorption data, hydrogen turnover numbers (mean, s.d., n = 3) and peak area ratios.
Hydrogen turnover numbers and chemical structures.
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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
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