2001 Volume 69 Issue 2 Pages 104-108
The electrochemiluminescence (ECL) of luminol in a hydrogen peroxide solution was studied by an electrochemical impedance spectroscopy (EIS). Parallel Pt wire electrodes in a flow-type spiral cell were used for the measurements of ECL. A superoxide ion, O2−, was generated by electrooxidation of H2O2 on Pt, and a luminol was oxidized on Pt. The oxidized luminol fluoresces by a reaction with O2−. An ECL impedance L, which is the ratio of the luminescence amplitude to the current in the frequency domain, was measured. By comparing the theoretical equation with the experimental results of L, the rate constant for luminol luminescence was determined.