Synthesis, characterization of a new photosensitive compound [Ru(bpy)2 (TPAD)](PF6)2 and its application for photocatalytic hydrogen production

A new photosensitive compound based on triphenylamine donor and ruthenium(II), namely [Ru(bpy)2 (TPAD)](PF6)2 (PS1, bpy = 2,2′-bipyridine, TPAD = N-(4-(1H-imidazo [4,5-f][1,10]phenanthroline-2-yl)phenyl)-N-phenylbenzenamine), had been synthesized and characterized. The target photocatalyst, PS1/0.5 wt% Pt/TiO2, was prepared. The influence of some key parameters on hydrogen production was investigated, respectively. The total amount of hydrogen evolution reached to 9500 μmol·(g·catalyst)−1 within 5.5 h with visible light irradiation under the optimal conditions (λ > 420 nm). Mechanistic studies suggest that PS1 can be excited under illumination of visible light and the excited PS1∗ can inject electrons to the conduction band (CB) of TiO2 to initiate the catalytic reactions.100