唑类缓蚀剂在铜表面的吸附机理

发布时间：2019-02-26 16:10

【摘要】：目的对比三氮唑(TA)和苯并三氮唑(BTA)两种缓蚀剂的缓蚀性能,明确两种缓蚀剂在铜表面的吸附类型,并从实验和分子模拟角度解释其吸附机理。方法采用动电位极化曲线法测试两种缓蚀剂的缓蚀效率,采用吸附等温拟合方法确定两种缓蚀剂的吸附类型,采用分子模拟中的量子化学计算方法计算两种缓蚀剂在铜表面的吸附能、形变电荷密度和分波态密度等参数,深入揭示其吸附机理。结果在不同浓度下,BTA的缓蚀效率均大于TA。两种缓蚀剂浓度与覆盖度的关系符合Langmuir吸附模型,其吸附自由能介于-35~-37 k J/mol之间。BTA在铜表面的吸附能绝对值(顶位为4.41 e V,桥位为4.36e V)要大于TA的吸附能绝对值(3.28 e V),吸附过程发生了明显的电荷转移,电子云处于两个成键原子之间,且N原子s,p轨道与Cu原子d轨道发生重叠。中性和质子化形式的两种缓蚀剂分子均可在铜表面发生平行吸附。结论由于BTA在铜表面的吸附能力强于TA,因此BTA的缓蚀性能优于TA。两种缓蚀剂在铜表面既能发生化学吸附,又能发生物理吸附。化学吸附是由于N原子的s,p轨道与Cu原子d轨道相互作用所致,物理吸附是由于中性分子的范德华相互作用和质子化分子的静电相互作用所致。
[Abstract]:Aim to compare the corrosion inhibition properties of triazole (TA) and benzotriazole (BTA), and to clarify the adsorption types of the two inhibitors on copper surface, and to explain the adsorption mechanism of the two inhibitors from the point of view of experiment and molecular simulation. Methods the inhibition efficiency of the two inhibitors was measured by potentiodynamic polarization curve method, and the adsorption types of the two inhibitors were determined by the adsorption isotherm fitting method. The adsorption energy, deformation charge density and partial wave state density of the two inhibitors on copper surface were calculated by quantum chemistry calculation method in molecular simulation, and the adsorption mechanism was revealed. Results the corrosion inhibition efficiency of BTA was higher than that of TA. at different concentrations. The relationship between the concentration of the two inhibitors and the coverage is in accordance with the Langmuir adsorption model. The free energy of the two inhibitors is between-35 and 37 k J/mol, and the absolute value of the adsorption energy of BTA on the surface of copper is 4.41 EV, The bridge site is 4.36eV), which is greater than the absolute value of the adsorption energy of TA (3.28 e V),). The electron cloud is located between two bonding atoms, and the N atom s, p orbital overlap with the d orbital of Cu atom. Both neutral and protonated inhibitor molecules can be adsorbed parallel to each other on the copper surface. Conclusion because the adsorption ability of BTA on copper surface is stronger than that of TA, the corrosion inhibition performance of BTA is better than that of TA.. Both chemisorption and physical adsorption of the two inhibitors can occur on the surface of copper. Chemisorption is due to the interaction between p-orbitals and d-orbitals of Cu atoms. The physical adsorption is due to the van der Waals interaction of neutral molecules and the electrostatic interaction of protonated molecules.
【作者单位】：中海油常州涂料化工研究院有限公司;中国石油大学(华东)理学院;
【基金】：山东省自然科学基金(ZR2012BM010,ZR2014EL003) 中央高校基本科研业务费专项资金(15CX02066A)~~
【分类号】：TG174.42

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