2-Mercaptobenzoxazole as a copper corrosion inhibitor in chloride solution: Electrochemistry, 3D-profilometry, and XPS surface analysis

•Corrosion of Cu follows kinetic-controlled and diffusion-controlled processes.•The diffusion coefficient through solid surface layer was reported.•2-Mercaptobenzimidazole is a mixed-type corrosion inhibitor.•Cu(I) ions and 2-mercaptobenzoxazole form Cu(I)–MBOH complex on the Cu surface.•The thickness of the 2-mercaptobenzoxazole surface layer is 1.4 ± 0.4 nm.

2-Mercaptobenzoxazole (MBOH) was studied as a corrosion inhibitor for Cu in 3 wt.% NaCl solution using EIS, a potentiodynamic curve, 3D-profilometry, and XPS measurements. It was shown that Cu corrosion in solution containing MBOH follows kinetic-controlled and diffusion-controlled processes and that MBOH is a mixed-type inhibitor. The diffusion coefficient of the Cu ions travelling through the solid surface layers was estimated to be on the order of 10−15–10−14 cm2 s−1. It was also demonstrated that the Cu(I)–MBOH complex is formed on the Cu surface and that the thickness of this surface layer is 1.4 ± 0.4 nm.