Combined Electrochemical and DTF Approaches to Elaeagnus Angustifolia Extract as a Green Corrosion Inhibitor for Mild Steel in HCl Solution

This study examines the corrosion inhibition properties of water extracts from Elaeagnus angustifolia (EA extract) fruit on mild steel (MS) in a 1 M HCl solution. The study assesses the effectiveness of different concentrations of EA extract as an eco-friendly corrosion inhibitor. The methodology employed includes gravimetric measurements, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), scanning electron microscopy (SEM), and density functional theory (DFT) calculations. The results show that increasing the concentration of the EA extract enhances the inhibition efficiency. At 100 mg/L, EA extract achieved inhibition efficiencies of 82.4 % (gravimetric), 92.8 % (EIS), and 86.9 % (PDP), indicating strong protective behavior. Additionally, the data best aligns with the Langmuir adsorption isotherm model. Quantum chemical calculations further confirm the adsorption of EA extract organic molecules on the surface, helping to explain the corrosion inhibition mechanism.