Computational and experimental studies of the inhibitory effect of imidazole derivatives for the corrosion of copper in an acid medium

Abstract

The inhibitory efficiencies of the molecules tested are determined using weight loss measurements, potentiodynamic polarization and electrochemical impedance (EIS). The adsorption of 1-Methylimidazole and 1H-benzimidazole on metallic surface reinforced with SEM-EDS and UV–Visible analysis of copper surface. These imidazole derivatives are heterocyclic organic compounds containing nitrogen atoms and are of great interest because of their multiple pharmacological activities. A theoretical simulation is achieved for the series of systems studied using density functional theory (DFT) to determine their electronic, structural and energetic properties. Monte Carlo simulation was performed to know well of the relationship between the inhibition ability and molecular structure of imidazole derivatives, the results of the potentiodynamic polarization indicate that the imidazole derivatives are mixed type inhibitors. These reduce the speed of the corrosion process for an optimal concentration of 10-3M. Electrochemical impedance spectroscopy (EIS) shows the presence of a single capacitive loop in favor of the charge transfer mechanism, the corrosion inhibition efficiency of 1-Methylimidazole and and 1H-benzimidazole exceeds approximately 66% 80% respectively. The adsorption of the compounds was found to obey Langmuir adsorption isotherm. A good agreement is observed between the results obtained by the different experimental techniques. Theory-experience correlations are established.