Electrochemical, chemical and theoretical exploration of the corrosion inhibition of carbon steel with new imidazole-carboxamide derivatives in an acidic environment

Metal corrosion is one of the problems that pose a serious threat to many industries, due to the damage it causes to metal parts, especially those made of steel. Thence, many researchers are constantly interested in finding simple and inexpensive solutions to this. Using a combination of experimental and theoretical explorations, N-(Butylidene)-5-(3,3-Dimethyltriaz-1-en-1-yl)-1H-Imidazole-4-Carboxamide (BDIC) was investigated as an inhibitor of carbon steel corrosion in 1 M HCl solution. The corrosion inhibitory effectiveness increased with increasing BDIC concentration. At 25 °C, the maximum inhibition efficiencies determined by weight loss (WL), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) techniques were 89.5 %, 89.0 %, and 90.2 %, respectively at 1 × 10–3 M of BDIC concentration. Polarization measurements revealed that BDIC has a mixed-type inhibitory action, reducing the anodic/cathodic partial reaction. The chemical and physical adsorption of BDIC onto the steel surface followed the Langmuir isotherm. The aqueous adsorption orientation of BDIC molecules on the carbon steel surface was investigated using DFT & MD simulation approaches. The experimental routes closely match the theoretical findings.