Salama Eid E, Alrashdi Saad, Boraei Ahmed T A, Eid Salah, Gomaa Islam, Gad Ehab S, Elhenawy Ahmed A, Nady Hashem
Department of Chemistry, College of Science, Jouf University, Sakaka 72341, Aljouf, Saudi Arabia.
Department of Chemistry, Faculty of Science, Suez Canal University, Ismailia 41522, Egypt.
Molecules. 2025 Mar 10;30(6):1235. doi: 10.3390/molecules30061235.
Ethyl 3-formyl-1H-indol-2-carboxylate (FIC) and 2-(4-methoxyphenyl)-2,4-dihydropyrrolo [3,4-b]indol-3-ol (MPI) were synthesized as indole derivatives. The chemical structures of FIC and MPI were established through analytical and spectroscopic techniques. The inhibitory impacts of FIC and MPI on mild steel (MS) in an acidic environment (0.5 M HSO) were investigated by employing methodologies including open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP). As the studied indole derivatives adsorbed on the surface of MS, they created a barrier to mass and charge movement, shielding the MS from dangerous ions. It was observed that the inhibitory efficiency (%EF) values increased with the molar concentration of indole derivatives (FIC and MPI). At all concentrations, the two indole derivatives being studied, FIC and MPI, had high efficiency values. The highest efficiencies at 90 ppm were 81.2% with MPI and 76.2% with FIC. The polarization curves also clearly showed that MPI and FIC function as mixed-type inhibitors. Additionally, this study used density functional theory (DFT) and molecular dynamics (MD) simulations to investigate how well the two indole derivatives prevented mild steel corrosion.
合成了3-甲酰基-1H-吲哚-2-羧酸乙酯（FIC）和2-(4-甲氧基苯基)-2,4-二氢吡咯并[3,4-b]吲哚-3-醇（MPI）作为吲哚衍生物。通过分析和光谱技术确定了FIC和MPI的化学结构。采用开路电位（OCP）、电化学阻抗谱（EIS）和动电位极化（PDP）等方法，研究了FIC和MPI在酸性环境（0.5 M H₂SO₄）中对低碳钢（MS）的抑制作用。当所研究的吲哚衍生物吸附在低碳钢表面时，它们对质量和电荷移动形成了屏障，使低碳钢免受危险离子的侵害。观察到抑制效率（%EF）值随吲哚衍生物（FIC和MPI）的摩尔浓度增加而升高。在所有浓度下，所研究的两种吲哚衍生物FIC和MPI都具有较高的效率值。在90 ppm时，MPI的最高效率为81.2%，FIC为76.2%。极化曲线还清楚地表明，MPI和FIC作为混合型缓蚀剂起作用。此外，本研究使用密度泛函理论（DFT）和分子动力学（MD）模拟来研究这两种吲哚衍生物对低碳钢腐蚀的抑制效果。
