Electrochemical and Quantum Chemical Calculations of Two Schiff Bases as Inhibitor for Mild Steel Corrosion in Hydrochloric Acid Solution

Document Type: Original research article


Department of Chemistry, Payame Noor University, P.O. Box 19395-4697, Tehran, I.R. Iran


The corrosion inhibition characteristics of two synthesized Schiff bases, namely N, N´-bis(2-hydroxy-6-nitrobenzaldehyde) benzidine  and N, N´-bis(salysylaldehyde) benzidine, on the mild steel corrosion in 2.0 M hydrochloric acid have been investigated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy techniques. These studies were carried out at different concentrations, temperatures and durations. Polarization measurements indicate that the two inhibitors act as mixed type inhibitors. The adsorption of inhibitors obeys the Langmuir adsorption isotherm and the thermodynamic parameters (Ea, Kads, ΔG0ads) were calculated and discussed. Quantum chemical calculations were performed to provide further insight into the inhibition efficiencies determined experimentally.