In order to explore the effect mechanisms of corrosion products of pure iron on its corrosion behaviors, the effects of Fe3O4, β-FeOOH and γ-FeOOH on the corrosion behavior of pure iron were investigated using scanning vibration electrode technique (SVET). Based on the semiconducting properties of the corrosion products, the mechanism of this effect was studied by scanning Kelvin probe (SKP), Mott-Schottky curve and oxygen reduction reaction polarization curve. Results showed that all three corrosion products could promote pure iron corrosion, and the promotion effect of three corrosion products on pure iron corrosion weakened in order of β-FeOOH, Fe3O4, and γ-FeOOH. The corrosion-promotion effect of corrosion products on pure iron depended on two factors: the relative magnitude of the work function of corrosion product and the work function of pure iron, and the oxygen reduction reaction activity of the corrosion product. When the work function of corrosion product was higher than that of pure iron, electrons were inclined to transfer from metal to corrosion product, accelerating the anodic reaction of pure iron corrosion process. In addition, the higher the oxygen reduction reaction activity of the corrosion product, the more favorable to the electron consumption, promoting the cathodic reaction of corrosion process.
