期刊名称：Journal of Materials and Environmental Science
印刷版ISSN：2028-2508
出版年度：2020
卷号：11
期号：3
页码：404-420
出版社：University of Mohammed Premier Oujda
摘要：Graphene oxide (GO) was synthesized by the modified Hummer’s method and then functionalized by initially reacting with urea and subsequently with thiourea to produce GO-amine (GOA) and GOB, respectively. These compounds were characterized by Raman shift, X-ray diffraction, field-emission scanning electron microscopy, and energy-dispersive x-ray spectroscopy techniques. The three chemicals were evaluated as anticorrosion inhibitors for carbon steel alloy (C1025) against an acidic medium (0.1 M hydrochloric acid) at 298 K through the electrochemical method (Tafel plot method). Results revealed that the efficiencies of GO, GOA, and GOB were 77.4%, 91.7%, and 87%, respectively, at their optimal concentration of 100 ppm. The effects of temperature on the corrosion reaction were also examined. The efficiency was found to decrease with increased temperature to 298, 308, 318, and 328 K. Kinetic parameters including activation energy (Ea), activation enthalpy (ΔH*), Gibbs free energy of activation (ΔG*) and activation entropy (ΔS*) were evaluated. Kinetic and thermodynamic parameters were used to calculate Ea in the presence or absence of each inhibitor to determine the physical adsorption mode on the surface of carbon steel. Results showed that the adsorption modes obeyed the Langmuir method of adsorption according to their R2 value, which approached unity.
