Characterization of the Excited State Properties of Some New Photosensitizers of the Ruthenium (Polypyridine) Family

Abstract The photophysical and electron transfer properties of the lowest excited state of nine ruthenium (polypyridine) complexes have been characterized. The complexes studied are Ru (bpy) 3‐n (LL) 2+ n , where n varies from 0 to 3, and LL is 4, 4′‐di‐ t ‐butyl‐2,2′‐bipyridine (DTB‐bpy), 3, 3′‐dimethyl‐2, 2′‐bipyridine (DM‐bpy), or a 2, 2′‐diquinolyl derivative (DMCH). The results obtained show that the Ru (bpy) 2 (DMCH) 2+ complex is expected to be a more efficient mediator than Ru (bpy) 2+ 3 in the water‐splitting reaction by solar energy.