A nature inspired molecular Ni-catalyst for efficient photocatalytic CO2 reduction to CO under visible light

Development of efficient molecular catalysts for photocatalytic COreduction is desirable but challenging. At present, the majority of reported molecular catalysts consist of the transition metal centers coordinated by N-containing ligands. Inspired by the sulfur-containing active site found in carbon monoxide dehydrogenases, we here report a novel Ni-based molecular catalyst bearing 2,6-bis([(2-pyridinylmethyl)thio]methyl) pyridine) as the pentadentate ligand. The product is assessed for photocatalytic COreduction in acetonitrile/water solution using Ru(bpy)Clas the photosensitizer and triethanolamine as the electron donor.Under the optimal condition, a total of ca.25 μmol CO is produced after 7 h visible light irradiation with a large turnover number of 63 and high selectivity of 91%.