几种氨基酸类缓蚀剂在铁表面吸附的第一性原理研究（英文）

发布时间：2018-03-03 08:38

本文选题：碳钢　切入点：缓蚀剂　出处：《表面技术》2017年04期 　论文类型：期刊论文

【摘要】：目的氨基酸是一类重要的环境友好型金属有机缓蚀剂,研究缓蚀剂分子在金属表面的吸附行为,对深入理解缓蚀机理及设计新型缓蚀剂分子有重要的理论意义。方法基于第一性原理框架下的原子轨道线性组合方法,采用Dmol3软件研究了甘氨酸、丙氨酸和亮氨酸三种分子在铁表面的吸附行为。首先对铁晶体表面的形貌学参数进行了计算,然后选取合适的晶面作为吸附表面。最后通过计算三种分子在铁表面的吸附能和分波态密度等参数分析缓蚀机制。结果铁的三种常见晶面中,Fe(110)面为最佳吸附表面。三种氨基酸分子在Fe(110)表面呈竖直型吸附构型,甘氨酸、丙氨酸和亮氨酸的吸附能绝对值大小分别为2.233、2.254、2.472 eV,这与其实验缓蚀效率大小顺序相一致。结论缓蚀剂分子吸附可导致金属基底的功函数减小。Hirshfeld电荷分析表明,吸附过程中存在从氨基酸分子到Fe(110)表面的电子转移现象。态密度分析表明,氨基酸分子中的活性原子与铁表面原子形成了共价键,键能的大小对缓蚀剂分子的缓蚀效率起决定性作用。
[Abstract]:Objective Amino acid is an important kind of environment-friendly organometallic corrosion inhibitor. The adsorption behavior of inhibitor molecules on metal surface is studied. It is of great theoretical significance to understand the mechanism of corrosion inhibition and to design new inhibitor molecules. Methods based on the atomic orbital linear combination method based on the first principle framework, glycine was studied by Dmol3 software. Adsorption behavior of alanine and leucine on iron surface. Finally, the corrosion inhibition mechanism was analyzed by calculating the adsorption energy and density of partial wave states of the three molecules on the iron surface. The results showed that the Fe _ (10) surface was the best adsorption surface in the three common crystal surfaces of iron. The three kinds of amino acid molecules were adsorbed vertically on the surface of Fe _ (110), and the three amino acids were adsorbed on the surface of Fe _ (110). The absolute values of adsorption energy of glycine, alanine and leucine are 2.233n 2.254 ~ 2.472 EV, respectively, which is consistent with the order of inhibition efficiency. Conclusion the molecular adsorption of inhibitor can reduce the work function of metal substrate. Hirshfeld charge analysis shows that the adsorption of glycine, alanine and leucine can reduce the energy function of metal substrate. During the adsorption process, the electron transfer from amino acid molecule to Fe (10) surface is observed. The density of states analysis shows that the active atom in amino acid molecule forms covalent bond with iron surface atom. The magnitude of bond energy plays a decisive role in the inhibition efficiency of corrosion inhibitor molecules.
【作者单位】：铜仁学院材料与化学工程学院;土耳其共和国大学理学院化学系;材料腐蚀与防护四川省重点实验室;
【基金】：Supported by the National Natural Science Foundation of China(51462030) the Science and Technology Program of Guizhou Province(QKHJC2016-1149) the Research Fund for the Doctoral Program of Tongren University(trxy DH1510) Guizhou Provincial Department of Education Foundation(QJHKYZ2016-105) the Opening Project of Sichuan University of Science and Engineering(2016CL06) and the student's platform for innovation and entrepreneurship training program(2016106665)~~
【分类号】：TG174.42

【相似文献】