Ruthenium(II) trisbipyridine functionalized gold nanorods. Morphological changes and excited-state interactions

Gold nanorods synthesized using cetyltrimethylammonium bromide and tetraoctylammonium bromide as stabilizers are functionalized with a thiol derivative of ruthenium(II) trisbipyridyl complex [(Ru(bpy)(3)(2+)-C-5-SH] in dodecanethiol using a place-exchange reaction. The changes in the plasmon absorption bands and transmission electron micrographs indicate significant changes in the gold rod morphology during the place-exchange reaction. The (Ru(bpy)(3)(2+)-C-5-SH in its excited state undergoes quick deactivation when bound to gold nanorods. More than 60% of the emission was quenched when [(Ru(bpy)(3)(2+)-C-5-SH] was bound to gold nanorods. Emission decay analysis indicates that the energy transfer rate constant is greater than 10(10) s(-1).