Correlations between the inhibition performances and the inhibitor structures of some azoles on the galvanic corrosion of copper coupled with silver in artificial seawater

• Published in: Corrosion science 2020-04, Vol.165, p.108413, Article 108413
• Main Authors: Huang, Hualiang, Bu, Furong
• Format: Article
• Language: English
• Subjects: A. Copper; A. Silver; B. EIS; B. SEM; B. XPS; Benzotriazole; Chemisorption; Copper; Corrosion inhibitors; Coupling (molecular); Galvanic corrosion; Heterocyclic compounds; Mercaptobenzimidazole; Molecular dynamics; Quantum chemistry; Seawater; Surface analysis (chemical)
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2019.108413

•The inhibition performances of inhibitors on the galvanic corrosion of copper coupled with silver were studied.•The effect of the introduction of nitrogen atom and sulfhydryl group on inhibition effect was evaluated.•Correlations between inhibition performances and inhibitor structures were determined.•The galvanic effect reduced the inhibition performances of inhibitors. The inhibition performances of benzimidazole (BI), 2-mercaptobenzimidazole (MBI) and benzotriazole (BTA) on the galvanic corrosion of copper coupled with silver in 3.5 wt.% NaCl solution have been investigated by electrochemical measurements, surface analysis, quantum chemical calculations and molecular dynamics simulations. The results demonstrate that the introduction of nitrogen atom and sulfhydryl group into benzimidazole molecule enhances the physisorption and chemisorption of inhibitors on the copper surface and improves the inhibition efficiency of inhibitors, while the galvanic effect between copper and silver reduces the inhibition efficiency of inhibitors. The difference of the inhibition performances of the three inhibitors is also elucidated.