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 π‐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).

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 pi-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 [Fe(I)Fe(0)] species – in accordance with theoretical calculations – presumably driving photocatalysis effectively (TON ≈ 210).

Photocatalysis In their Communication (e202202079), Masaichi Saito, Stephan Kupfer, Benjamin Dietzek‐Ivanšić, Wolfgang Weigand et al. utilize a precious metal‐free photocatalyst consisting of a [FeFe] hydrogenase mimic for hydrogen generation under visible light.

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 pi-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 [Fe(I)Fe(0)] species – in accordance with theoretical calculations – presumably driving photocatalysis effectively (TON ≈ 210).