物理化学学报 >> 2010, Vol. 26 >> Issue (05): 1385-1390.doi: 10.3866/PKU.WHXB20100501

量子化学及计算化学 上一篇    下一篇

咪唑啉缓蚀剂在Fe(001)表面吸附行为的分子动力学模拟

张军, 于维钊, 燕友果, 于立军, 任振甲   

  1. 中国石油大学物理科学与技术学院, 山东 东营 257061
  • 收稿日期:2009-11-04 修回日期:2010-01-19 发布日期:2010-04-29
  • 通讯作者: 燕友果 E-mail:dynamic_zh@163.com

Molecular Dynamics Simulation of the Adsorption Behavior of Imidazoline Corrosion Inhibitors on a Fe(001) Surface

ZHANG Jun, YU Wei-Zhao, YAN You-Guo, YU Li-Jun, REN Zhen-Jia   

  1. College of Physics Science and Technology, China University of Petroleum, Dongying 257061, Shandong Province, P. R. China
  • Received:2009-11-04 Revised:2010-01-19 Published:2010-04-29
  • Contact: YAN You-Guo E-mail:dynamic_zh@163.com

摘要:

采用分子动力学模拟方法研究了5种不同烷基链长的咪唑啉类缓蚀剂在Fe(001)表面的吸附行为和成膜机制, 并对其缓蚀机理进行了深入分析. 研究结果表明: 咪唑啉分子的极性头基会吸附在金属表面上, 而烷基碳链则背离金属表面, 并通过自身的扭转形变实现稳定吸附; 随着烷基链长的增加, 缓蚀剂与金属基体的结合强度逐渐增加, 所形成缓蚀剂膜的致密性也逐渐增大; 致密的缓蚀剂膜能有效地阻碍腐蚀介质向金属表面扩散, 从而达到延缓金属腐蚀的目的. 5种缓蚀剂缓蚀性能的理论评价结果与实验结果吻合.

关键词: 咪唑啉, 分子动力学模拟, 吸附能, 缓蚀效率, 缓蚀剂膜

Abstract:

The adsorption behaviors of five imidazoline corrosion inhibitors with different alkyl chain lengths on a Fe(001) surface were investigated by molecular dynamics simulation method, and the inhibition mechanism was also discussed in depth. The results demonstrate that the head group of the imidazoline molecule is attached to the metal surface while the alkyl chain deviates from the metal surface. Stable corrosion inhibitor molecule absorption is achieved by self-distortion. Additionally, the combination of corrosion inhibitor and metal surface strengthens with the elongation of the alkyl chain, and the density of the corrosion inhibitor monolayer also increases. As a result, the formed dense corrosion inhibitor monolayer efficiently restrains the diffusion of the corrosive media from the liquid phase to the metal surface, which delays its corrosion. A theoretical evaluation of the corrosion inhibition performance of five corrosion inhibitors agrees well with the experimental results.

Key words: Imidazoline, Molecular dynamics simulation, Adsorption energy, Corrosion inhibition efficiency, Corrosion inhibitor monolayer

MSC2000: 

  • O646.05