Adsorption of 2-mercaptobenzimidazole corrosion inhibitor on copper: DFT study on model oxidized interfaces
| Main Authors: | Chiter, Fatah, Costa, Dominique, Maurice, Vincent, Marcus, Philippe |
|---|---|
| Format: | Article Journal |
| Bahasa: | eng |
| Terbitan: |
, 2020
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/4309742 |
Daftar Isi:
- High corrosion inhibition efficiency of the 2-mercaptobenzimidazole (MBI) molecule for copper in different aqueous solutions is well established. We propose a first principle DFT study of the surface chemistry of the adsorption of MBI on preoxidized Cu(111). For both thione (MBIH) and thiolate (MBI◦) species, the formation of a full monolayer (ML) is favored over low coverage adsorption. At the ML coverage, the molecules adopt a perpendicular orientation with respect to the surface. MBI◦ interaction with the surface is stronger than MBIH one. MBIH and MBI◦ bond to the surface forming a S–Cu bond; for MBIH, the NH moiety forms a H-bond with a surface oxygen atom; for MBI◦, a N–Cu bond is formed. For MBI◦ at low coverage, a Cu–C bond is also formed. The charge analyses show a charge transfer between the surface and the molecule. Comparing the MBIH/MBI◦ adsorption energies with that of water/OH, we find that MBI◦ can replace H2O and OH at the preoxidized Cu surface. The results are compared with those obtained with 2-mercaptobenzothiazole, a similar azole derivative with corrosion inhibition properties.