Department of Chemical Engineering, Faculty of Engineering, Golestan University, Iran; Department of Surface Coatings and Corrosion, ICST, Tehran, Iran.
Department of Chemical Engineering, Faculty of Engineering, Golestan University, Iran.
J Colloid Interface Sci. 2021 Dec;603:716-727. doi: 10.1016/j.jcis.2021.06.130. Epub 2021 Jun 25.
Silane (sol-gel)-based coatings have been introduced as an eco-friendly system for reducing the metals' corrosion in NaCl solutions. However, due to the lack of active protection property for this type of coatings, their modification is totally recommended for achieving durable protection properties. The present study introduces Beta-cyclodextrin (β-CD) as a novel/effective organic nano-container for Benzimidazole (BM) encapsulation to obtain reliable active protection property via a controlled-release property.
The chemical structure of the β-CD-BM macromolecule was explored by Fourier-transform infrared spectroscopy (FT-IR), X-Ray diffraction (XRD), and Ultraviolet-visible spectroscopy (UV-Vis). Besides, the Electrochemical Impedance Spectroscopy (EIS) and polarization (potentiodynamic) tests were carried out for investigating the inhibition impacts of the constructed containers. The exposed and unexposed samples' surfaces were analyzed by Field Emission Scanning Electron Microscope (FE-SEM), Energy Dispersive Spectroscopy (EDS)/mapping, and Grazing incidence X-ray diffraction (GIXRD) experiments. Also, the EIS test was conducted over the Silane-based composite film (SCF) for analyzing the anti-corrosion performance of the constructed composites.
The EIS achievements demonstrated that by the addition of β-CD-BM complexes to the saline solution, the mild steel corrosion was mitigated by about 84%. The EIS results also displayed that the total resistance of the modified composite was enhanced from 5540 Ω.cm to 10967 Ω.cm and the intact coating provided a total resistance of 80254 Ω.cm. The dispersion-corrected Density Functional Theory (DFT)-D explorations ascertained the inclusion capacity of benzimidazole inside the β-CD. The Monte Carlo/Molecular Dynamics (MC/MD) calculations strongly affirmed the adsorption of BM and β-CD-BM over the substrate.
基于硅烷（溶胶-凝胶）的涂层已被引入作为一种减少 NaCl 溶液中金属腐蚀的环保系统。然而，由于这种类型的涂层缺乏主动保护性能，因此完全建议对其进行改性，以获得持久的保护性能。本研究介绍了β-环糊精（β-CD）作为一种新型/有效的有机纳米容器，用于苯并咪唑（BM）的封装，通过控制释放特性获得可靠的主动保护性能。
通过傅里叶变换红外光谱（FT-IR）、X 射线衍射（XRD）和紫外可见光谱（UV-Vis）研究了β-CD-BM 大分子的化学结构。此外，还进行了电化学阻抗谱（EIS）和极化（动电位）测试，以研究构建容器的抑制作用。通过场发射扫描电子显微镜（FE-SEM）、能量色散光谱（EDS）/mapping 和掠入射 X 射线衍射（GIXRD）实验分析了暴露和未暴露样品的表面。此外，还对基于硅烷的复合膜（SCF）进行了 EIS 测试，以分析构建复合材料的防腐性能。
EIS 结果表明，通过向盐水溶液中添加β-CD-BM 配合物，可将低碳钢腐蚀减轻约 84%。EIS 结果还显示，改性复合膜的总电阻从 5540 Ω.cm 增加到 10967 Ω.cm，完整涂层提供了 80254 Ω.cm 的总电阻。修正的密度泛函理论（DFT-D）计算证实了苯并咪唑在β-CD 内的包合能力。蒙特卡罗/分子动力学（MC/MD）计算强烈证实了 BM 和β-CD-BM 在基质上的吸附。
