Pourmohseni Maryam, Rashidi Alimorad, Karimkhani Mehrnoosh
Department of Chemistry Central Tehran Branch, Islamic Azad University, Tehran, Iran.
Nanotechnology Research Center, Research Institute of Petroleum Industry (RIPI), Tehran, Iran.
Sci Rep. 2024 Apr 4;14(1):7937. doi: 10.1038/s41598-024-58637-z.
In the present study, the inhibition performance of some medicinal plants (i.e. Yarrow, Wormwood, Maurorum, Marjoram, and Ribes rubrum) was theoretically and experimentally investigated for mild steel immersed in 1M HCl. In this way, the obtained extracts characterized by Fourier transform infrared spectroscopy (FT-IR) and the electrochemical and theoretical techniques were used to study the inhibition mechanisms of the extracts for the immersed electrode in the acidic solution. In addition, the microstructure of the electrode surface immersed in the blank and inhibitor-containing solutions characterized by field emission scanning electron microscopy (FE-SEM), and Violet-visible (UV-Vis) spectroscopy was used to confirm the adsorption of the compounds on the electrode surface. The obtained electrochemical results revealed that the inhibition performance of the green inhibitors increased by increasing their dosage in the electrolyte. In addition, it was proved that Marjoram plant extract possessed the most inhibition efficiency (up to 92%) among the under-studied herbal extracts. Marjoram extract behaved as a mixed-type inhibitor in the hydrochloric acid solution, and the adsorption process of the extract on the steel surface followed the Langmuir adsorption model. Adsorption of the compounds on the steel surface was also studied using density functional theory (DFT), and it was found that the protonated organic compounds in the extract have a high affinity for adsorption on the electrode surface in the acidic solution.
在本研究中，对一些药用植物（即蓍草、艾草、毛罗勒、马郁兰和红醋栗）对浸入1M盐酸中的低碳钢的缓蚀性能进行了理论和实验研究。通过这种方式，用傅里叶变换红外光谱（FT-IR）对所得提取物进行表征，并用电化学和理论技术研究提取物对酸性溶液中浸入电极的缓蚀机理。此外，用场发射扫描电子显微镜（FE-SEM）对浸入空白溶液和含缓蚀剂溶液中的电极表面微观结构进行表征，并用紫外可见（UV-Vis）光谱证实化合物在电极表面的吸附。所得电化学结果表明，绿色缓蚀剂的缓蚀性能随其在电解液中用量的增加而提高。此外，证明在研究的草药提取物中，马郁兰植物提取物具有最高的缓蚀效率（高达92%）。马郁兰提取物在盐酸溶液中表现为混合型缓蚀剂，提取物在钢表面的吸附过程遵循朗缪尔吸附模型。还使用密度泛函理论（DFT）研究了化合物在钢表面的吸附，发现提取物中的质子化有机化合物在酸性溶液中对电极表面具有高吸附亲和力。
