Homogeneous Electron Transfer Reactions of Electrochemically Generated Species in Electrogenerated Chemiluminescence

Abstract

Electrogenerated Chemiluminescence (ECL) involves electrode reactions and the following homogeneous electron transfer reactions which resulted in a light emission. In this integrated research paper, we focused on the homogeneous electron transfer reactions to form excited states of some luminescent molecules. The Marcus theory was used to estimate ratios of the electron-transfer rate constants between a radical cation and anion to generate the lowest excited singlet and triplet states. In addition, the ECL behavior using tripropylamine as a coreactant was demonstrated by simulating the electrochemical and homogeneous electron transfer reactions with a finite element method. Although coreactants are useful to form excited species, because of complicated reactions in bulk, analyzing the ECL response such as relationship between the current-voltage and ECL intensity curves depending on the redox potentials of luminescent molecules and coreactants is quite difficult. It was shown that the simulations were very useful to understand the ECL response depending on the redox potentials of the coreactant and luminescent molecules.