Abstract:

An o-phenanthroline-substituted ruthenium complex, [Rubis(bipyridyl) (3,4,7,8-tetrachrolo-1,10-phenanthroline)](PF6)2, has been synthesized and the structure of the complex was characterized by element analysis, IR spectroscopy and proton NMR spectroscopy. The complex displays absorptions in the UV and visible regions, with visible maximum absorption at 440 nm, a typical metal-to-ligand charge transfer (MLCT) transitions. Photoluminescence emission also has the characteristics of the MLCT transitions with the maxima wavelengths ranged from 630 to 649 nm depending on the different solvents. The electrochemiluminescence (ECL) of the complex was found to be less dependant on the pH, which was distinctly different from that of the well known ruthenium tris(bipyridine) complex. Furthermore the background ECL signal of the complex did not increase even in a strong alkaline condition.

Key words: Ruthenium tris(bipyridine) complex, Electrochemiluminescence, 3,4,7,8-Tetrachrolo-o-phenanthroline, pH effect