Unique electrochemiluminescence behavior of Ru(bpy)32+ in a gold/Nafion/Ru(bpy)32+ composite

The unique electrochemiluminescence (ECL) behavior of tris(bipyridine) ruthenium(II) (Ru(bpy)32+) immobilized in a gold/Nafion/Ru(bpy)32+ composite material was investigated. In this composite, the Ru(bpy)32+ ECL was found mainly occurred at 0–0.4 V during the cathodic scan process and the ECL peak was at about 0.1 V, which was quite different to the reported Ru(bpy)32+ ECL. Similar to the generally observed Ru(bpy)32+ ECL, the present ECL also could be enhanced by tri-n-propylamine (TPA). It is also unique that in the presence of TPA, another ECL peak at about 0.38 V occurred. These two ECL peak potentials all could be used as characteristic potential for the ECL determination of TPA.