Design and synthesis of new triazole derivative as a copper corrosion inhibitor in NaCl solution: a combined electrochemical and theoretical study

In this study, a novel triazole compound named 2-(4-((2-methoxy-4-vinylphenoxy)-methyl)-1H-1,2,3-triazol-1-yl)ethan-1-ol (MTE) was synthesized from eugenol, extracted from cloves (Syzygium aromaticum). Eugenol is a natural phenolic compound renowned for its cost-effective and eco-friendly attributes, rendering it a preferred option for industrial uses. The newly prepared triazole was characterized by FTIR and ¹H NMR techniques. For the first time, the inhibitory potential of MTE against copper corrosion in a 3.5 wt.% NaCl solution was investigated using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) methods. At 1 mM, MTE demonstrated an exceptional ability to inhibit corrosion, achieving an efficacy rate of 94.03%, and exhibited mixed-type inhibitor characteristics. The EIS study showed that the MTE compound formed a thin protective film on the copper surface. X-ray energy dispersive spectroscopy (EDX) coupled with scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR-ATR) were used to characterize the protective film formed by MTE on the copper surface. The analyses confirmed the presence of MTE on the copper surface. Furthermore, our results suggest that the adsorption of MTE on the copper surface follows a Langmuir isotherm model. In addition, the negative adsorption-free energy ( \({\Delta G^\circ }_{ads}=-37.19\mathrm{ kJ}/{\text{mol}}\) ${\mathrm{\Delta }{G}^{\circ }}_{\mathit{ads}}=-37.19\mathrm{kJ}/\text{mol}$ ) indicates a spontaneous adsorption process. In the field of copper corrosion inhibition in 3.5 wt.% NaCl solutions, theoretical calculations hold great promise. Density functional theory (DFT) and molecular dynamics (MD) simulations are particularly powerful tools. These simulations provide a window into the interactions between MTE molecules and the copper surface at the atomic level. This helps elucidate the mechanisms by which MTE prevents the adsorption of corrosive chloride ions, ultimately protecting the copper from degradation.