Corrosion inhibition with a perezone-impregnated Mg/Al hydrotalcite coating in AS21 alloy
Por:
Casillas, Gabriel Espinosa, Vazquez, Araceli Espinoza, Gómez F.J.R., Vasquez, Araceli Perez, Mata, Rachel, Miralrio, Alan, Castro, Miguel, Martinez, Ricardo Galvan, Cruz, Ricardo Orozco
Publicada:
10 jul 2023
Ahead of Print:
1 may 2023
Resumen:
The effect of perezone concentration and the behavior of the
hydrotalcite MgAl coating impregnated with the perezone on the AS21
magnesium alloy were studied using electrochemical impedance
spectroscopy (EIS). The results show that the perezone molecule protects
the magnesium surface, with the best concentration being 10 ppm. When
the inhibitor was impregnated with the hydrotalcite, the corrosion
protection was significantly improved, reaching 91.1% inhibition
efficiency. In order to elucidate the adsorption mechanism of perezone
on magnesium surfaces, density functional theory calculations (DFT)
within a cluster approach were carried out. The Pearson's Hard-Soft
Acid-Base theoretical framework reveals, by means of several global
parameters, a strong interaction between perezone and the metal surface.
Two different adsorption modes were studied in deep. The mixed
physisorption-chemisorption process was rationalized in terms of the
interactions between the organic molecule and the Mg10 magnesium
cluster. Perezone molecule is adsorbed by the oxygen atoms of the
substituted quinone ring, whereas the physical component can be
explained by the electrostatic interactions between them. The metal
cluster transferred charge to the corrosion inhibitor molecule is of
about 0.507 e. The formation of a protective layer was observed by means
of SEM-EDS and explained by the Fukui reactivity indices.
Filiaciones:
Casillas, Gabriel Espinosa:
Departamento de Ingeniería Metalúrgica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México, 04510, Mexico
Vazquez, Araceli Espinoza:
Unidad Anticorrosión, Instituto de Ingeniería, Universidad Veracruzana, Veracruz, Boca del Río, 94294, Mexico
Gómez F.J.R.:
Departamento de Ingeniería Metalúrgica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México, 04510, Mexico
Vasquez, Araceli Perez:
Departamento de Farmacia, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México, 04510, Mexico
Mata, Rachel:
Departamento de Farmacia, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México, 04510, Mexico
Miralrio, Alan:
Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Av. Eugenio Garza Sada 2501, NL, Monterrey, 64849, Mexico
Castro, Miguel:
Departamento de Física y Química Teórica, DEPg. Facultad de Química, UNAM, Del. Coyoacán, Ciudad de México, 04510, Mexico
Martinez, Ricardo Galvan:
Unidad Anticorrosión, Instituto de Ingeniería, Universidad Veracruzana, Veracruz, Boca del Río, 94294, Mexico
Cruz, Ricardo Orozco:
Unidad Anticorrosión, Instituto de Ingeniería, Universidad Veracruzana, Veracruz, Boca del Río, 94294, Mexico
|