The influence of 5,5',5''-(nitrilotris (methylene)) tris-(8-quinolinol), noted (NMQ8), on mild steel corrosion in 1 M HCl was studied by weight loss, electrochemical, scanning electron microscopy (SEM), theoretical calculation and molecular dynamic methods. The results obtained for NMQ8 showed a good inhibition effect on the mild steel in the 1 M HCl solution. The inhibition efficiency was found to increase with a corresponding increase in the NMQ8 concentration, and the best inhibition of 92.78% occurred at a NMQ8 concentration of 1 mM. The potentiodynamic studies revealed that investigated NMQ8 act as mixed type inhibitor. Activation energy (Ea), equilibrium constant (Kads), free energy of adsorption (ΔG°ads) were calculated and discussed. The studied inhibitor obeyed Langmuir's adsorption isotherm. The adsorption behavior and inhibition mechanism of studied compound on the surface of mild steel were studied by quantum chemical calculations and molecular dynamics (MD) simulations. It was found that the compound show the highest ability to donate and accepting electrons while the MD simulations show the high adsorption energy of the molecules on Fe (110) surface.
Keywords: Mild Steel; Molecular dynamic; Corrosion Inhibition; DFT; Fukui Functions; quinoline.