A Bisamide Ruthenium Polypyridyl Complex as a Robust and Efficient Photosensitizer for Hydrogen Production

Abstract A photosensitizer based on a ruthenium complex of a bisamide‐polypyridyl ligand gives rise to a large improvement in photocatalytic stability, rate of activity, and efficiency in photocatalytic H 2 production compared to [Ru(bpy) 3 ] 2+ (bpy=2,2′‐bpyridine). The bisamide ruthenium polypyridyl complex combined with a cobaltoxime‐based photocatalyst was found to be highly efficient under blue‐light (turnover number (TON)=7800) and green‐light irradiation (TON=7200) whereas [Ru(bpy) 3 ] 2+ was significantly less effective with a TON of 2600 and 1100, respectively. The greatest improvement was under red‐light‐emitting diodes, with bisamide ruthenium polypyridyl complex and cobaltoxime exhibiting a TON of 4200 compared to [Ru(bpy) 3 ] 2+ and cobaltoxime at a TON of only 71.