Experimental and theoretical investigation of 3-amino-1,2,4-triazole-5-thiol as a corrosion inhibitor for carbon steel in HCl medium

Abstract

The inhibition effect of 3-amino-1,2,4-triazole-5-thiol (3ATA5T) was investigated in 0.5 M HCl on carbon steel (CS) by electrochemical impedance spectroscopy and potentiodynamic measurements at various concentrations and temperatures. Results showed that the correlation between experimental (inhibition efficiencies, Δ G ads , E a ) and quantum calculation parameters (dipole moment, E HOMO , E LUMO ). The high inhibition efficiency was declined in terms of strongly adsorption of protonated inhibitor molecules on the metal surface and forming a protective film.