Investigation of the inhibitor effect of pyrazine derivatives against the corrosion of mild steel in acid media

In this study, inhibition performance of pyrazine derivatives against corrosion on mild steel (MS) in 0.5 M HCl solution investigated at different concentrations and temperatures by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) methods. Furthermore, the morphology of MS surface was monitored in absence and presence inhibitor by atomic force microscope (AFM) and scanning electron microscopy (SEM). It is seen that the inhibition efficiency increased when inhibitor's concentration is increased, and decreased when the temperature is increased. The potentiodynamic polarization results indicate that all the studied inhibitors examined show as mixed type inhibitor characteristics. Pyrazine derivatives adsorption on the MS surface conformed to the isotherm of Langmuir and thermodynamic parameters; Kads, ∆G○ads, Ea were also calculated and evaluated.