Corrosion Inhibition Behavior of Indazole Derivative as a Green Corrosion Inhibitor for Mild Steel in Hydrochloric Acid: Electrochemical, Weight Loss and DFT Simulations Studies

Abstract

The effect of Indazole derivative (AY20) against the corrosion of mild steel (MS) in 1 M acidic chloride (HCl) solution was investigated by chemical (weight loss – WL) and electrochemical (Tafel polarization and Electrochemical impedance spectroscopy) techniques. From all the four methods, it is inferred that the percentage of inhibition efficiency increases with increasing the inhibitor concentration from 10 -3 M to 10 -6 M. The adsorption behavior of inhibitor obeyed through Langmuir isotherm model. EIS technique exhibits one capacitive loop indicating that, the corrosion reaction is controlled by charge transfer process. Tafel polarization studies revealed that the investigated inhibitor is mixed type and the mode of adsorption is chemical in nature. Theoretical quantum chemical calculations were performed to confirm the ability of (AY20) to adsorb onto mild steel surface. The results obtained from different techniques are in good agreement.