Identifying a Real Catalyst of [NiFe]‐Hydrogenase Mimic for Exceptional H2 Photogeneration

Abstract

AbstractInspired by the natural [NiFe]‐H2ase, we designed mimic 1, (dppe)Ni(μ‐pdt)(μ‐Cl)Ru(CO)2Cl to realize effective H2 evolution under photocatalytic conditions. However, a new species 2 was captured in the course of photo‐, electro‐, and chemo‐ one‐electron reduction. Experimental studies of in situ IR spectroscopy, EPR, NMR, X‐ray absorption spectroscopy, and DFT calculations corroborated a dimeric structure of 2 as a closed‐shell, symmetric structure with a RuI center. The isolated dimer 2 showed the real catalytic role in photocatalysis with a benchmark turnover frequency (TOF) of 1936 h−1 for H2 evolution, while mimic 1 worked as a pre‐catalyst and evolved H2 only after being reduced to 2. The remarkably catalytic activity and unique dimer structure of 2 operated in photocatalysis unveiled a broad research prospect in hydrogenases mimics for advanced H2 evolution.