Anticorrosive potential of essential oil extracted from the leaves of Calamintha plant for mild steel in 1 M HCl medium

Abstract

In the present work, essential oil of Calamintha (EOC) was extracted from Calamintha plant and characterized by gas chromatography-mass spectrometry (GC-MS) and FTIR technique. In addition, EOC was evaluated as an ecological corrosion inhibitor of mild steel in 1 M HCl medium by various electrochemical techniques. Satisfactory consistency was obtained between the gravimetric method, potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The maximum efficiency was recorded for the concentration of 1.5 g/L EOC which reached 87.57%. However, the morphology of the metal surface analyzed by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) showed the appearance of a protective barrier on the steel surface. Finally, a theoretical study was carried out on the basis of the density functional theory (DFT) and molecular dynamics (MD) simulation technique.