The effect of iodide ion on passive Film Breakdown of iron in a borate buffer containing chloride ion

Recently, passive film breakdown of Fe has been investigated in solutions of various anions by measuring the time required for breakdown, tbd and permeation of anions into the passive film using X-ray photoelectron spectroscopy. The results have been discussed on the basis of the hard and soft acids and bases (HSAB) principle. In previous study, the pitting and repassivation potentials of a passivated Fe electrode were measured in a borate buffer solution containing Cl. The effects of added I on pit initiation and growth were discussed using electronprobe microanalysis and based on the HSAB principle. In this paper, the results of the previous investigation are interpreted by considerations of the recent work in more detail.