Effect of anions on the anodic dissolution behavior of iron: An electrochemical and density functional theory study

The influences of SO42-, Cl-, ClO4- and BF4- on the corrosion behavior of Fe in acidic solutions were quantitatively investigated through macro- and micro-electrochemical techniques, combined with DFT calculation. The electrochemical results showed that the corrosion rate increased in the order of BF4-, ClO4-, Cl- and SO42-, confirmed by the negative shift of OCP and Ecorr, the decrease of Rct and the increase of k0eff of Fe oxidation. DFT calculation showed that the adsorption of SO42- on Fe(100) surface was easier and stronger than Cl-, and caused more significant Fe surface structure changes, resulting in more serious corrosion of Fe.