An electrochemical, long-term immersion, and XPS study of 2-mercaptobenzothiazole as a copper corrosion inhibitor in chloride solution

Abstract

Using EIS, potentiodynamic curve, 3D-profilometry, and XPS measurements, 2-mercaptobenzothiazole (MBTH) was studied as a corrosion inhibitor for Cu in 3wt.% NaCl solution. Electrochemical measurements showed that Cu corrosion in MBTH-inhibited solution follows kinetic-controlled and diffusion-controlled processes, that MBTH acts as a mixed-type inhibitor after 100h of immersion and that it significantly reduces surface roughness after half a year of immersion compared with non-inhibited solution. It is also shown that the N atom and exocyclic S atom of the MBTH are involved in the molecule adsorption. The MBTH surface layer thickness was estimated to be 1.5±0.5nm.