Tang Zijie, Wang Pengjie, Song Yuhao, Liu Wenchao, Ansari Kashif Rahmani, Lin Yuanhua
State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, Sichuan, P. R. China.
School of New Energy and Materials, Southwest Petroleum University, Chengdu 610500, Sichuan, P. R. China.
Langmuir. 2025 Jul 15;41(27):18134-18151. doi: 10.1021/acs.langmuir.5c02092. Epub 2025 Jul 2.
One of the reasons that corrosion inhibitors can work is due to the interaction between the benzene ring and the metal surface. Thus, investigating the impact of varying numbers of benzene rings on the corrosion inhibition efficiency is crucial. This study systematically examines the corrosion inhibition mechanisms of imidazole derivatives with different numbers of benzene rings on Q235 steel in 1.0 M HCl (OB represents one benzene ring, BB represents two benzene rings, and TB represents three). Electrochemical results indicate that the three inhibitors are mixed-type inhibitors, hindering both anodic dissolution and cathodic hydrogen evolution. Among them, the corrosion inhibition efficiency of TB at a concentration of 2.0 mM is 97.18%, which is superior to those of BB (94.45%) and OB (90.49%). Scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle measurement results demonstrate that the carbon steel surface after TB adsorption has the least corrosion products, the lowest roughness ( = 31.6 nm), and the highest hydrophobicity (contact angle = 84.62°). X-ray photoelectron spectroscopy (XPS) analysis confirmed that TB can more effectively inhibit the oxidation of iron. Theoretical calculations indicate that TB has a flatter adsorption configuration (MPP = 0.233 Å, SDP = 1.248 Å), stronger adsorption ability ( = 1585.46 kJ/mol), and a lower energy gap (Δ = 1.809 eV), which favor larger and more stable adsorption. The ELF-π reveals that TB has a wider π electron delocalization range, facilitating the formation of more interfacial bonding and effectively blocking the corrosive medium. The results of RDG further confirm that TB has better adsorption capacity, alleviating concerns about increased steric hindrance due to the higher number of benzene rings. This paper explores the relationship between the number of benzene rings and corrosion inhibition performance, proposing that π electrons enhance corrosion inhibition efficiency, thereby providing theoretical support for the design of polycyclic corrosion inhibitors.
缓蚀剂能够发挥作用的原因之一是苯环与金属表面之间的相互作用。因此，研究不同数量苯环对缓蚀效率的影响至关重要。本研究系统地考察了具有不同数量苯环的咪唑衍生物（OB代表一个苯环，BB代表两个苯环，TB代表三个苯环）在1.0 M HCl中对Q235钢的缓蚀机理。电化学结果表明，这三种缓蚀剂均为混合型缓蚀剂，同时抑制阳极溶解和阴极析氢。其中，2.0 mM浓度的TB缓蚀效率为97.18%，优于BB（94.45%）和OB（90.49%）。扫描电子显微镜（SEM）、原子力显微镜（AFM）和接触角测量结果表明，TB吸附后的碳钢表面腐蚀产物最少，粗糙度最低（ = 31.6 nm），疏水性最高（接触角 = 84.62°）。X射线光电子能谱（XPS）分析证实，TB能更有效地抑制铁的氧化。理论计算表明，TB具有更扁平的吸附构型（MPP = 0.233 Å，SDP = 1.248 Å）、更强的吸附能力（ = 1585.46 kJ/mol）和更低的能隙（Δ = 1.809 eV），有利于形成更大且更稳定的吸附。ELF-π表明TB具有更宽的π电子离域范围，有利于形成更多的界面键合并有效阻挡腐蚀介质。RDG结果进一步证实TB具有更好的吸附能力，消除了因苯环数量增加导致空间位阻增大的担忧。本文探讨了苯环数量与缓蚀性能之间的关系，提出π电子增强缓蚀效率，从而为多环缓蚀剂的设计提供理论支持。
