Oxide formation in the oxygen evolution region at Pt electrodes in M H2SO4

Oxide growth at Pt electrodes in M H₂SO₄ has been measured at potentials up to 2.2 V in the oxygen evolution region. The previously described model, in which nucleation is rate determining, remains applicable. There is no evidence for any change of oxide property or for partial arrests in the Q-E curve, throughout this range. The effects of potential and film thickness on the oxygen evolution reaction may be completely separated. This implies a dual site model for the two anodic reactions.