Inhibition of the initial stages of corrosion by 2-mercaptobenzothiazole adsorption and the effects of interfacial oxides on copper in neutral chloride conditions

Advanced surface analytical techniques were used to study 2-mercaptobenzothiazole (2-MBT) adsorption and interfacial oxide effects on copper, and cyclic voltammetry was used to characterize corrosion inhibition in NaCl solution. 2-MBT adsorbs on metallic copper by its sulphur atoms along with a small fraction of nitrogen atoms. The 2-MBT film formed is thicker when the interfacial oxide is less. Upon anodic polarisation, a direct correlation between the thickness of 2-MBT layer and protection against corrosion initiation is observed. The metal-organic complexes, formed by an interaction between 2-MBT and Cu(I) ions, do not offer additional protection to the substrate.