Studies of Inhibition effect “E & Z’’ Configurations of hydrazine Derivatives on Mild Steel Surface in phosphoiric acid

Abstract

Inhibition effect of ‘Cis and Trans’ conformations of three families of azines namely: [1.2-bis(pyrrole-2-ylidenemethyl) hydrazine (HZ1), 1.2-bis(thiophene-2-idenemethyl) hydrazine (HZ2) and 1,2-Bis(furyl-2-lidenemethyl) hydrazine (HZ3)] on mild steel corrosion in 2.0 M H3PO4, were investigated through electrochemical impedance spectroscopy, Weight loss measurements and X-ray diffraction. A compact HZi inhibitor film was fabricated on the steel surface, and the film showed high inhibition efficiency, also, a reduction of the inhibition efficiency IEexp(%) as the solution temperature. The isomers of Cis and Trans- HZi were studied on the basis of their degree of planarity, their local and global electronic properties as well as their deformation capacity to adhere to the Fe-surface, using DFT and molecular dynamic simulations. A comparative study by standard deviation (SD) of Cis- and Trans-HZi with DFT method shows the higher correlation between X-ray diffraction, 1H &13C NMR Chemical Shifts and Trans geometric form. The adsorption behaviour of the both forms (Cis & Trans)-HZi onto the Fe (111) face were investigated by Molecular Dynamics simulations in vacuo to verify their anti-corrosive efficiency. The results indicate that the adsorption energies, deformation energies and rigid adsorption energies of Trans-HZi was greater than Cis-HZi, which agree with the trends of the experimental inhibition efficiencies. Keywords: Azines, Corrosion inhibition, Trans & Cis-forms, FT-IR, X-Ray, NMR, DFT, Molecular Dynamics simulations.