Essential oil of Dysphania ambrosioides as a green corrosion inhibitor for mild steel in HCl solution

In this work, an essential oil was extracted from the leaves of Dysphania Ambrosioides (DA) and tested as an environmentally friendly corrosion inhibitor for mild steel in 1 M HCl medium. To improve and enrich the socio-economic environment by using eco-friendly, non-toxic and biodegradable products to reduce metal degradation in industrial sector. Different techniques were used in the study, namely mass loss, potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The results showed that corrosion inhibition efficiency of 84% was reached at a concentration of 1.5 g/l of the extract. The adsorption thermodynamics study showed that the adsorption of the inhibitor molecules on the steel surface followed the Langmuir isotherm. Micrographic analysis of the steel using SEM and AFM showed a smooth surface with reduced roughness in the presence of the inhibitor compared to that of the blank material. Theoretical investigations using density functional theory (DFT) and molecular dynamics simulations (MDS) revealed the possible sites responsible for the adsorption of the molecules in the DA extract on the steel surface, providing insights into the corrosion inhibition mechanism.