Kinetics of oxygen reduction at IrO₂-coated titanium electrode in alkaline solution

Oxygen reduction at IrO₂-coated titanium electrodes fabricated by thermal decomposition was investigated by employing cyclic voltammetry and rotating-disk electrode techniques. Cyclic voltammetric results indicated that oxygen reduction begins during the Ir(III)/Ir(IV) transition on an IrO₂ electrode. On the basis of measurements using a rotating disk electrode together with polarization curves, Tafel slopes, and stoichiometric number determinations, a mechanism for oxygen reduction on an IrO₂-coated titanium electrode is proposed.