Synthesis, spectroscopic characterization and a comparative study of the corrosion inhibitive efficiency of an α-aminophosphonate and Schiff base derivatives: Experimental and theoretical investigations

Abstract

New α-aminophosphonate (α-APD) and Schiff base (E-NDPIMA) derivatives have been prepared and their structures ware proved by IR, UV–Vis, 1H, 13C and 31P NMR spectroscopy. Their inhibitive capacities on the XC48 carbon steel corrosion in 0.5 mol L−1 H2SO4 solution were explored by weight loss, Tafel polarization, electrochemical impedance spectroscopy (EIS) and atomic force microscope (AFM). Experimental results illustrate that the synthesized compounds are an effectives inhibitors and the adsorption of inhibitors molecules on the carbon steel surface obeys Langmuir adsorption isotherm. In addition, quantum chemical calculations performed with density function theory (DFT) method have been used to correlate the inhibition efficiency established experimentally. Also, the molecular dynamics simulations have been utilized to simulate the interactions between the inhibitors molecules and Fe (100) surface in aqueous solution.