Corrosion Inhibition of Steel in Hydrochloric Acid Solution Using a Triazole Derivative: Electrochemical and Computational Studies

The efficiency of 5,5’-[butane-1,4-diylbis(sulfanediyl)bis(4-amino-4H-1,2,4-triazole-3-thiol)] (BATT) as a corrosion inhibitor for mild steel in 2 M HCl was studied using polarization and electrochemical impedance spectroscopy (EIS). The adsorption of the investigated inhibitor onto the steel surface was found to follow Langmuir isotherm. The negative value of the free energy of adsorption, Gads ensures the spontaneity of the adsorption process. The temperature effect on the corrosion of steel in 2 M HCl with and without inhibitor was also studied. Moreover, density functional theory (DFT) calculations give a clear indication of strong molecular interaction between inhibitor molecules and iron surface