Bedair Mahmoud A, Elaryian Hani M, Gad Ehab S, Alshareef Mubark, Bedair Ahmed H, Aboushahba Rabab M, Fouda Abd El-Aziz S
Department of Chemistry, Faculty of Science (Men's Campus), Al-Azhar University Nasr City 11884 Cairo Egypt
College of Science and Arts, University of Bisha P.O. Box 101 Al-Namas 61977 Saudi Arabia
RSC Adv. 2022 Dec 22;13(1):478-498. doi: 10.1039/d2ra06574f. eCollection 2022 Dec 19.
Two azo derivatives, 4-((4-hydroxy-3-((4-oxo-2-thioxothiazolidin-5-ylidene)methyl)phenyl) diazinyl) benzenesulfonic acid (TODB) and 4-((3-((4,4-dimethyl-2,6-dioxocyclohexylidene) methyl)-4-hydroxyphenyl)diazinyl) benzenesulfonic acid (DODB) were synthesized and characterized using Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (H-NMR) and mass spectral studies. Gravimetric methods, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), electrochemical frequency modulation (EFM) techniques and inductive coupled plasma-optical emission spectroscopy were used to verify the above two compounds' ability to operate as mild steel (MS) corrosion inhibitors in 1 M HCl. Tafel data suggest that TODB and DODB have mixed-type characteristics, and EIS findings demonstrate that increasing their concentration not only alters the charge transfer ( ) of mild steel from 6.88 Ω cm to 112.9 Ω cm but also changes the capacitance of the adsorbed double layer ( ) from 225.36 to 348.36 μF cm. At 7.5 × 10 M concentration, the azo derivatives showed the highest corrosion inhibition of 94.9% and 93.6%. The inhibitory molecule adsorption on the metal substrate followed the Langmuir isotherm. The thermodynamic activation functions of the dissolution process were also calculated as a function of inhibitor concentration. UV-vis, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) techniques were used to confirm the adsorption phenomenon. The quantum chemical parameters, inductively coupled plasma atomic emission spectroscopy (ICPE) measurements, and the anti-bacterial effect of these new derivatives against sulfate-reducing bacteria (SRB) were also investigated. Taken together, the acquired results demonstrate that these compounds can create an appropriate preventing surface and regulate the corrosion rate.
合成了两种偶氮衍生物，4-((4-羟基-3-((4-氧代-2-硫代噻唑烷-5-亚基)甲基)苯基)二嗪基)苯磺酸(TODB)和4-((3-((4,4-二甲基-2,6-二氧代环己叉基)甲基)-4-羟基苯基)二嗪基)苯磺酸(DODB)，并采用傅里叶变换红外光谱(FTIR)、质子核磁共振(H-NMR)和质谱研究对其进行了表征。采用重量法、动电位极化(PDP)、电化学阻抗谱(EIS)、电化学频率调制(EFM)技术和电感耦合等离子体发射光谱法来验证上述两种化合物在1 M HCl中作为低碳钢(MS)缓蚀剂的能力。塔菲尔数据表明TODB和DODB具有混合型特征，EIS结果表明，增加它们的浓度不仅会使低碳钢的电荷转移( )从6.88 Ω·cm改变为112.9 Ω·cm，还会使吸附双层的电容( )从225.36改变为348.36 μF·cm。在7.5×10 M浓度下，偶氮衍生物的缓蚀率最高，分别为94.9%和93.6%。缓蚀分子在金属基体上的吸附遵循朗缪尔等温线。还计算了溶解过程的热力学活化函数与缓蚀剂浓度的关系。采用紫外可见光谱、扫描电子显微镜(SEM)和能量色散X射线光谱(EDX)技术来证实吸附现象。还研究了这些新衍生物的量子化学参数、电感耦合等离子体原子发射光谱(ICPE)测量结果以及对硫酸盐还原菌(SRB)的抗菌效果。综合来看，所获得的结果表明这些化合物可以形成合适的防护表面并调节腐蚀速率。
