Corrosion inhibition of mild steel in acidic medium by simple azole-based aromatic compounds
Corrosion inhibition of mild steel in acidic medium by simple azole-based aromatic compounds
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DOI：
10.1016/j.jelechem.2020.114858
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发表时间：
2021-01-21
影响因子：
4.5
通讯作者：
Wipf, David O.
中科院分区：
文献类型：
--
作者：
Caldona, Eugene B.;Zhang, Min;Wipf, David O.
许多有机缓蚀剂是复杂的，可能包括复杂的化学结构，不同种类的混合物，或需要大量和繁琐的制备步骤。在这项研究中，我们证明了三唑和咪唑基化合物的抑制作用，这些化合物是一步合成的，具有严格的化学结构。采用电化学阻抗谱（EIS）、动电位极化、失重等方法研究了缓蚀剂对低碳钢在40℃1.0 M HCl溶液中的缓蚀效果。电化学测试结果表明，芳香族化合物在酸性介质中具有良好的缓蚀作用，缓蚀效率随缓蚀剂浓度的增加而增加。在850 μ m浓度下，三唑基化合物具有最佳的抑制性能（效率约为90%），其次是咪唑基化合物（效率约为85%）。扫描电子显微镜和原子力显微镜的分析结果表明，低碳钢的拓扑结构得到改善，表面粗糙度降低了5倍，x射线衍射显示了氧化层的形成程度。此外，拉曼光谱证实了金属表面的保护抑制剂层的吸附作用，并通过Langmuir吸附等温线和计算研究推测了其潜在的模式和机制，表明化合物的抑制能力与化合物的供电子和接受电子能力之间存在良好的相关性。
Many organic corrosion inhibitors are complex and may include complicated chemical structures, mixture of different species, or require numerous and tedious preparation steps. In this study, we demonstrate inhibition by triazole- and imidazole-based compounds, which are synthesized in a one-stepmethod and possess austere chemical structures. The inhibition effect was studied on the corrosion of mild steel in 1.0 M HCl solution at 40 degrees C by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, and weight loss. Results from electrochemical measurements showed that the aromatic compounds were effective in inhibiting corrosion in acidic medium, such that the inhibition efficiency increased with increasing inhibitor concentration. The triazole-based compound had the best inhibitive performance (efficiency >90%), followed by the imidazole-based (similar to 85%), at a concentration of 850 mu M. These results were supported by analyses obtained from scanning electron and atomic force microscopy, which showed improved mild steel topology and decrease in surface roughness by up to a factor of five, and x-ray diffraction, which revealed the extent of oxide layer formation. In addition, the adsorption of a protective inhibitor layer on the metal surface was confirmed by Raman spectroscopy, while the underlying mode and mechanism were postulated based on a Langmuir adsorption isotherm and computational studies, which showed good correlation between the inhibitive ability and the electron donating and accepting capability of the compounds.