Abstract

Three thiophenol derivatives with different substituent groups, 2-Naphthalenethiol (2-NT), 4-Chlorothiophenol (4-Cl) and p-Toluenethiol (4-MT) were selected to study the corrosion inhibition performance for copper in saline medium. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) measurements, and weight loss tests were performed to compare the effect of different concentrations and various types of thiophenol derivatives on corrosion inhibition performances. Scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and Surface-enhanced Raman spectroscopy (SERS) were utilized to characterize surface morphology and molecular structures of copper samples after corrosion in saline medium or electrochemical tests. Quantum chemical calculations were applied to further investigate the microscopic mechanism of the interaction between thiophenol derivative inhibitor molecules and copper surface. XPS, SERS, and theoretical calculations results indicate that thiophenol derivative inhibitors were adsorbed on Cu surface by Cu–S chemical bond. It was also found that these thiophenol derivative inhibitors could effectively inhibit the corrosion of copper by chemisorption and the efficiency follows the order of 2-NT >4-Cl >4-MT. The larger conjugated aromatic structure in 2-NT may be responsible for the measured higher inhibition efficiency of 2-NT.

摘要

选择了3种不同取代基的苯硫酚衍生物2-萘硫醇（2-NT）、4-氯苯硫酚（4-Cl）和对甲苯硫醇（4-MT），研究了铜在盐水介质中的缓蚀性能。进行了动电位极化、电化学阻抗谱 (EIS) 测量和失重测试，以比较不同浓度和各种类型的苯硫酚衍生物对缓蚀性能的影响。扫描电子显微镜 (SEM)、X 射线光电子能谱 (XPS) 和表面增强拉曼光谱 (SERS) 用于表征铜样品在盐水介质腐蚀或电化学测试后的表面形态和分子结构。应用量子化学计算进一步研究苯硫酚衍生物抑制剂分子与铜表面相互作用的微观机制。XPS、SERS和理论计算结果表明苯硫酚衍生物抑制剂通过Cu-S化学键吸附在Cu表面。还发现这些苯硫酚衍生物缓蚀剂可以有效地抑制化学吸附对铜的腐蚀，其效率依次为2-NT >4-Cl >4-MT。2-NT 中较大的共轭芳族结构可能是测量到的 2-NT 较高抑制效率的原因。理论计算结果表明，苯硫酚衍生物抑制剂通过Cu-S化学键吸附在Cu表面。还发现这些苯硫酚衍生物缓蚀剂可以有效地抑制化学吸附对铜的腐蚀，其效率依次为2-NT >4-Cl >4-MT。2-NT 中较大的共轭芳族结构可能是测量到的 2-NT 较高抑制效率的原因。理论计算结果表明，苯硫酚衍生物抑制剂通过Cu-S化学键吸附在Cu表面。还发现这些苯硫酚衍生物缓蚀剂可以有效地抑制化学吸附对铜的腐蚀，其效率依次为2-NT >4-Cl >4-MT。2-NT 中较大的共轭芳族结构可能是测量到的 2-NT 较高抑制效率的原因。