Corrosion inhibition of a new Schiff base derivative with two pyridine rings on Q235 mild steel in 1.0 M HCl

A new Schiff base derivative, namely 4-(((4-(bis(pyridin-2-ylmethyl) amino) phenyl) imino) methyl)-N,N-diethylaniline, with more than one pyridine ring and two benzene rings was synthesized successfully. And then its corrosion inhibition properties were estimated in 1.0 M HCl by weight loss experiments, potentiodynamic polarization and electrochemical impedance spectroscopy methods. The results showed that 4-(((4-(bis(pyridin-2-ylmethyl) amino) phenyl) imino) methyl)-N,N-diethylaniline is a mixed type inhibitor and follows Langmuir adsorption isotherm. SEM-EDX and XPS techniques were used for surface analysis. Meanwhile, quantum chemical calculation using density functional theory (DFT) established the correlation between the structure and corrosion inhibition efficiency. Molecular dynamic simulation was adopted to investigate the adsorption behavior on mild steel surface.