Kinetic insight of multi-molecule adsorption behaviors into the anticorrosion performance of azole inhibitors: A reactive force field molecular dynamics study

• Published in: Journal of molecular liquids 2024-11, Vol.414, p.126079, Article 126079
• Main Authors: Chang, Pengfei, Huang, Zisheng, Chen, Yulong, Ling, Huiqin, Wu, Yunwen, Li, Ming, Hang, Tao
• Format: Article
• Language: English
• Subjects: 1,2,4-Triazole; Adsorption kinetics; Benzotriazole; Corrosion inhibitor; Molecular dynamics; Reactive force field
• ISSN: 0167-7322
• DOI: 10.1016/j.molliq.2024.126079

[Display omitted] •Multi-molecule adsorption behaviors of imidazole, 1,2,4-triazole and benzotriazole on copper were investigated.•The adsorption kinetics elucidated the enormous difference in their inhibitory performance while DFT calculation failed.•Benzotriazole consistently exhibited significantly faster and more frequent adsorption on copper surface. Density functional theory (DFT) calculations and molecular dynamics (MD) simulations are established as powerful tools in understanding the anti-corrosion mechanism of inhibitors at the atomic scale. Despite their widespread popularity, DFT calculations typically focus on small adsorption models while the inhibition efficiency of inhibitors is determined by multi-molecule adsorption film on metal surface. Classical MD simulations neglect the formation of chemical bonding, which frequently governs the overall adsorption process. In this contribution, reactive force field (ReaxFF) MD simulations were employed to overcome these limitations and investigate the differences in inhibitory capabilities among three classic azole compounds: imidazole (IDZ), 1,2,4-triazole (TAZ), and benzotriazole (BTA) on copper. Electrochemical tests and microscopic observations revealed that BTA demonstrated superior inhibitory effect on copper corrosion compared to IDZ and TAZ. However, the widely used descriptor, adsorption energy (Eads) in DFT calculations for predicting the inhibition ability of inhibitors were very similar, failing to explain the enormous variation in inhibition effectiveness. To explain this disparity, multi-molecule adsorption kinetics based on ReaxFF simulations were conducted. The results showed that BTA consistently demonstrated faster and more frequent adsorption on copper surface compared to the other two. The significant variance in inhibitory efficiency among the three inhibitors was elucidated for the first time from the kinetic insight.