The Electrochemical Luminescence Properties and Applications of Benzofuranone Compounds

Abstract

In this work, we selected two benzofuranone derivatives, phthalide (PA) and coumaranone (Cmno), as the luminophores for electrochemiluminescence (ECL). During the experiments, we employed K₂S₂O₈ as the co-reactant and observed that both compounds could generate ECL signals in K₂S₂O₈ solution. By analyzing their cyclic voltammetry curves, fluorescence spectra, and ECL spectra, among others, we speculated on the ECL mechanisms of these two systems. To further compare the differences in ECL signals between the two systems, we employed density functional theory (DFT) to calculate their molecular orbital energy levels. The results indicated that Cmno is more likely to form an excited state, producing a stronger ECL signal. This theoretical result is consistent with the results obtained from the ECL intensity–potential curves. Additionally, we discovered that 2-dimethylaminoethanol (DMAEA) significantly quenches the ECL signal of Cmno, and this quenching depended on the concentration of DMAEA. Based on these findings, we developed a simple, sensitive, and highly selective method for detecting the concentration of DMAEA.