Synthesis and characterization of pyrazole-acetamide schiff bases as highly effective inhibitors for mild steel in 1 M HCl

Abstract

Two Schiff base compounds, WG1 and WG2, were successfully synthesized by reacting N-(2-aminophenyl)-2-(5-methyl-1H-pyrazol-3-yl)acetamide with aromatic aldehydes. This study delved into exploring the capacity of these heterocyclic compounds to inhibit mild steel (MS) from corrosion when exposed to 1 M HCl solution, using electrochemical techniques (potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS)). Moreover, scanning electron microscopy (SEM) coupled with energy-dispersive X-ray (EDX) was utilized throughout the investigation. The findings indicated that both derivatives were effective corrosion inhibitors. WG1 showed a high inhibitory efficiency of 94.9 %, followed by WG2 (94.1 %) at a small concentration of 10⁻⁴ M. The inhibitors adsorbed on the working electrode surface following Langmuir isotherm. Additionally, the adsorption capacity of these inhibitors is verified through density functional theory (DFT) and Monte Carlo (MC) simulations.