The Mechanism of Oxygen Reduction on Iron in Neutral Solutions

The pathways and rate‐determining steps of oxygen reduction on iron in neutral p H range have been investigated. The various mechanistic criteria are obtained as a function of the nature of the electrode surface: bare iron and passive iron. The oxygen reduction on bare iron proceeds through 4 e − pathways with little hydrogen peroxide as an intermediate and formation of superoxide radical in the rds. On passive iron, oxygen reduction proceeds through a 2 e − pathway with the formation of hydrogen peroxide as a reaction product. An rds involving chemisorption of oxygen is suggested.