Optical Studies of the Formation and Breakdown of Passive Films Formed on Iron Single Crystal Surfaces in Inorganic Inhibitor Solutions

Abstract

Polarized light was used to measure the thickness and optical properties of passive films as they were forming while simultaneous electrochemical measurements were being made. The film formation studies showed that a change in film thickness of 15–20Aå was associated with the onset of a passive potential. A direct, logarithmic‐type law governed the growth of a semiconductor film with crystallographic orientation of the substrate having little effect.