Molecular Dynamics Study of the Adsorption of Benzimidazole and its Derivatives on Fe surface

The adsorption behavior of five corrosion inhibitors including benzimidazole, 2-propyl benzimidazole, 2-amyl benzimidazole, 2-hexyl benzimidazole and 2-chloro-benzyl benzimidazole on Fe surface was studied by using molecular dynamics(MD) method. The inhibition efficiency of the five corrosion inhibitors was measured by weight loss method and polarization curve testing. The results show that the order of the adsorption energy of five corrosion inhibitors calculated by the molecular dynamics method is benzimidazole<2-propyl benzimidazole<2-amyl benzimidazole<2-hexyl benzimidazole<2-chloro-benzyl benzimidazole, which is in good accordance with the inhibition efficiency obtained by weight loss method. Radial distribution function of the five adsorbing systems was analyzed and it is found that the five corrosion inhibitors can all establish chemical adsorption with Fe surface.