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Photocatalytic Hydrogen Evolution by a Synthetic [FeFe] Hydrogenase Mimic Encapsulated in a Porphyrin Cage.

ABSTRACT: The design of a biomimetic and fully base metal photocatalytic system for photocatalytic proton reduction in a homogeneous medium is described. A synthetic pyridylphosphole-appended [FeFe] hydrogenase mimic was encapsulated inside a supramolecular zinc porphyrin-based metal-organic cage structure Fe₄ (Zn-L)₆ . The binding is driven by the selective pyridine-zinc porphyrin interaction and results in the catalyst being bound strongly inside the hydrophobic cavity of the cage. Excitation of the capsule-forming porphyrin ligands with visible light while probing the IR spectrum confirmed that electron transfer takes place from the excited porphyrin cage to the catalyst residing inside the capsule. Light-driven proton reduction was achieved by irradiation of an acidic solution of the caged catalyst with visible light.

SUBMITTER: Nurttila SS

PROVIDER: S-EPMC6282596 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Photocatalytic Hydrogen Evolution by a Synthetic [FeFe] Hydrogenase Mimic Encapsulated in a Porphyrin Cage.

Nurttila Sandra S SS Becker René R Hessels Joeri J Woutersen Sander S Reek Joost N H JNH

Chemistry (Weinheim an der Bergstrasse, Germany) 20181009 61

The design of a biomimetic and fully base metal photocatalytic system for photocatalytic proton reduction in a homogeneous medium is described. A synthetic pyridylphosphole-appended [FeFe] hydrogenase mimic was encapsulated inside a supramolecular zinc porphyrin-based metal-organic cage structure Fe<sub>4</sub> (Zn-L)<sub>6</sub> . The binding is driven by the selective pyridine-zinc porphyrin interaction and results in the catalyst being bound strongly inside the hydrophobic cavity of the cage. ...[more]

PMID: 30117602

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