Assessment of New Imidazol Derivatives and Investigation of Their Corrosion-Reducing Characteristics for Carbon Steel in HCl Acid Solution

Abstract

This study assessed the corrosion inhibitory and adsorption properties of two imidazol derivatives, namely 5-((2,4,5-triphenyl-1H-imidazol-1-yl)methyl)quinolin-8-ol (TIMQ) and 5-((2-(4-chlorophenyl)-4,5-diphenyl-1H-imidazol-1-yl)methyl)quinolin-8-ol (CDIQ), on carbon steel (CS) in 1 M of HCl using electrochemical methods, including electrochemical impedance spectroscopy (EIS), potentiodynamic polarization measurements (PDP), UV–visible spectroscopy (UV–v), scanning electron microscopy (SEM), and molecular modeling. The findings showed that TIMQ and CDIQ were potent inhibitors with inhibition efficiencies of 94.8% and 95.8%, respectively. The potentiodynamic polarization experiments showed that the inhibitors worked as mixed-type inhibitors, and the impedance investigations supported the improvement of a protective layer for the inhibitor on the metal surface. Each inhibitor was adsorbed onto the carbon steel surfaces, according to the Langmuir adsorption method. The steel was shielded from acidic ions by an adsorbed coating of the inhibitor molecules, according to SEM. Density functional theory (DFT) calculations and molecular dynamics (MD) simulations were used to inspect the results, and a good correlation was found between these results and those of the study. This information can be applied to determine the effectiveness of inhibitors in a HCl acid solution.