Synthèse caractérisation mise en évidence de l'efficacité inhibitrice de corrosion et des propriétés biologiques d'une nouvelle série de dérivées α-aminophosphonates: etude expérimentale et théorique

Abstract

In this work we have synthesized four new compounds: two Schiff bases and their correspondent’s α-aminophosphonates derivatives. The molecular structures of the synthesized compounds have been determined using the spectroscopic methods UV-Vis, IR, 1H, 13C and 31P NMR. Moreover, a comparative study of the corrosion inhibitive activity of the synthesized compounds on the carbon steel in 0.5 M H2SO4 solution has been performed using weight loss, polarization curves and electrochemical impedance spectroscopy methods. The obtained results indicate that the studied compounds are efficient mixed-type inhibitors and their inhibition efficiencies increased with increasing inhibitors concentrations. The adsorption of the inhibitors molecules on the carbon steel surface follows Langmuir isotherm and their thermodynamic parameters are obtained. The morphologies of the carbon steel surfaces after exposing in electrolytic solutions were examined by atomic force microscopy (AFM). The quantum chemical parameters were calculated employing the density functional method (DFT). The interaction between inhibitor and Fe (100) surface are performed by molecular dynamic simulations. Finally, the antioxidant activities of the synthesized compounds were evaluated using the DPPH and the reducing power of ferric ions methods