Effect of nonionic fluorosurfactant on the electrogenerated chemiluminescence of the tris(2,2'-bipyridine)ruthenium(II)/tri-n-propylamine system: lower oxidation potential and higher emission intensity.

Fluorosurfactants are commercially available, and their applications in electrochemical systems have been the interest of many studies. Here, we describe a novel effect of a nonionic fluorosurfactant (Zonyl FSN) on the electrogenerated chemiluminescence (ECL) of the tris(2,2'-bipyridine)ruthenium(II)/tri-n-propylamine (TPrA) system at gold and platinum electrodes. Compared with its hydrocarbon analogue (Triton X-100), the adsorbed fluorosurfactant species not only rendered the electrode surfaces more hydrophobic but also significantly retarded the growth of the electrode oxide layers. As a result, more facile direct oxidation of TPrA was achieved, which led to the appearance of a low oxidation potential ECL signal (below 1.0 V vs SCE). At the gold electrode, the ECL peak appeared at 0.82 V, approximately 400 mV more negative than usual; while its intensity was approximately 50 times higher. The generation of the intense ECL signal at low oxidation potential may lead to the development of more efficient ECL analysis.