Alternating current and ring-disc electrodes

Abstract

The theory of alternating current experiments at a ring-disc electrode has been confirmed using the ferri-ferrocyanide system. The frequency range has been extended using phase-sensitive detection. At higher frequencies the passage of current through the electrolyte resistance causes charging of the ring electrode double layer and the results have to be corrected for this. Results for the Br₂/Br^– system show that species are adsorbed on the electrode. The most probable hypothesis is that Br· is the species involved and an estimate can be obtained for its surface coverage. This allows the calculation of the rate constant for e + Br·→ Br^–, and the mechanistic implications of the value found are discussed.