Electrochemical and theoretical analysis of a novel spirocyclopropane derivative for corrosion inhibition of mild steel in acidic medium

Abstract

The adsorption behavior and corrosion inhibition mechanism of 1-benzoyl-2-(4-methoxyphenyl)-6,6-dimethyl-5,7-dioxaspiro[2.5]octane-4,8-dione (Pt-5) on the Fe surface, in HCl medium, have been studied using both experimental and theoretical approaches. The effectiveness of corrosion inhibition has been evaluated by the use of electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and weight loss methods.It was found that Pt-5 has a maximum inhibition efficiency of 92.85% at a concentration of 5×10^-3 M, and it is clear from data obtained using Pt-5 corrosion test results that the inhibition efficiency increases with increasing inhibitor concentration. The inhibitor's adsorption process follows the Langmuir isotherm while the thermodynamic parameters underwent discussion. This inhibitor can be adsorbed onto surfaces by physical and chemical means.The inhibitory efficiencies obtained from the experimental techniques agreed well with the calculated quantum chemical parameters based on DFT / B3LYB / 6-31G (d, p) and MD simulation results.