Cathodic electrochemiluminescence behavior of Eosin B and its quenching mechanism by Cr3+

A novel electrochemiluminescence (ECL) system consisting of Eosin B (EB) and K2S2O8 was studied and found to generate ECL following the oxidation or reduction of Eosin B and K2S2O8. The type of buffer solution, type of co-reactant, pH value, and K2S2O8 concentration were optimized through experiments to make the reaction system reach the best value. In addition, we found that Cr3+ has a great quenching effect on the EB reaction system. Through the comparison of ECL and CV under different conditions, DPV curve, UV spectrum and ECL spectrum experiments, we focused on the quenching mechanism of Cr3+ on the system and made reasonable guesses. This method demonstrates the potential application value of ECL in the field of environmental monitoring and reveals the potential value of organic molecular ECL luminophores.