Activating a[FeFe] Hydrogenase Mimic for Hydrogen Evolution under Visible Light
in: Angewandte Chemie-International Edition (2022)
Inspired by the active center of the natural [FeFe] hydrogenases, we designed a compact and precious metal-free photosensitizer-catalyst dyad (PS-CAT) for photocatalytic hydrogen evolution under visible light irradiation. PS-CAT represents a prototype dyad comprising -conjugated oligothiophenes as light absorbers. PS-CAT and its interaction with the sacrificial donor 1,3-dimethyl-2-phenylbenzimidazoline were studied by steady-state and time-resolved spectroscopy coupled with electrochemical techniques and visible light-driven photocatalytic investigations. Operando EPR spectroscopy revealed the formation of an active [FeIFe0] species – in accordance with theoretical calculations – presumably driving photocatalysis effectively (TON ≈ 210).