Experimental and Theoretical Study of Corrosion Inhibition of Mild Steel in 1.0 M HCl Medium by 2(-4( hloro phenyl-1H- benzo[d]imidazol)-1-yl)phenyl)methanone

The 2(-4(chloro phenyl-1H- benzo[d]imidazol)-1-yl)phenyl)methanone (CBIPM) was synthesized and tested as a corrosion inhibitor for mild steel in 1.0 M HCl solution using electrochemical and spectroscopy measurements. Results obtained showed that this compound has a good inhibition properties for mild steel corrosion in acidic medium which its inhibition efficiency value reaches 98.9 % at 10-3 M. So, the potentiodynamic polarization curves showed that the CBIPM has a mixed type inhibitor. In addition, it is shown that the obtained results were confirmed by the UV-vis spectroscopic measurements. It is found that the inhibitor forms a complex with Fe2+ ion. On the other hand, the experimental results were completed by quantum chemical calculations using DFT method at the B3LYP/6-31G* level of theory. It is found that the theoretical and experimental results are in good agreement.

本研究合成并表征了2-[4-(氯苯基)-1H-苯并[d]咪唑-1-基]苯基甲酮（CBIPM），将其作为缓蚀剂应用于1.0 M盐酸溶液中的碳钢腐蚀防护，并采用电化学与光谱测试手段开展性能评估。实验结果表明，该化合物对酸性介质中的碳钢腐蚀具有优异的缓蚀性能，在浓度为10⁻³ M时，其缓蚀效率可达98.9%。动电位极化曲线测试结果显示，CBIPM属于混合型缓蚀剂。此外，紫外-可见（UV-vis）光谱测试验证了上述实验结论，研究发现该缓蚀剂可与Fe²+离子形成配合物。另一方面，本研究采用密度泛函理论（DFT）方法，在B3LYP/6-31G*基组水平上开展量子化学计算，对实验结果进行补充完善。结果表明，理论计算与实验结果具有良好的一致性。