Electrogenerated chemiluminescence at bare glassy carbon electrode in basic media

Abstract Electrogenerated chemiluminescence (ECL) with three peaks at bare glassy carbon electrode (GCE) was observed as potential scanning between 0 and 2.6 V vs. Ag/AgCl in basic media. The peak potentials were seated at ca. 1.36 V, 1.72 V and 2.34 V in the positive sweeping, denoted as from ECL-I to ECL-III, respectively. Mechanisms of such ECL phenomena were proposed. For ECL-I peaked at 1.36 V, it might attribute to the oxidation of surface functional groups that analogy to alcoholic hydroxyl connected to the skeleton of GCE (S–R–CH 2 OH), and the following ECL-II at 1.72 V, to the further oxidation of their products (S–R–CHO) to carbonyl compound (S–R–COO − ). While for ECL-III at a high positive potential ca. 2.34 V, it was supposed to be related to the formation of singlet O 2 and its further conversion to triplet state.