Aplication of dynamic impedance spectroscopy for construction of adsorption isotherms of molybdate ions on magnesium alloy
https://doi.org/10.29235/1561-8323-2026-70-2-126-134
Abstract
Dynamic electrochemical impedance spectroscopy was used to examine the corrosion behavior of AZ31 magnesium alloy in 0.05 mol/dm3 sodium chloride solution containing Na2MoO4 inhibitor, which was gradually added to the solution up to the concentration of 50 mmol/dm3. The parameters of multisinusoidal impedance monitoring obtained under these conditions corresponded to the instantaneous concentration of the inhibitor at a specific point in time. This made it possible to establish the dependence of the calculated values of the protective effect on the concentration of molybdate ions in the solution. Based on the assumption that complete coverage of the surface by the inhibitor provides 100 % reduction of the corrosion rate and the surface degree coverage corresponds to the protective effect of the inhibitor, the adsorption curves of molybdate ions on the surface of AZ31 magnesium alloy were constructed utilizing Langmuir, Temkin, Flory–Huggins, and Frumkin adsorption models.
Keywords
magnesium alloy,
sodium molybdate,
corrosion inhibitor,
dynamic electrochemical impedance spectroscopy,
inhibition efficiency,
adsorption isotherm
Supporting agencies: This work was supported by the Belarusian Republican Foundation for Fundamental Research (grant no. Х24МВ-008), and State Program of Scientific Investigations “Chemical processes and technologies”, task 3.
About the Authors
M. A. Osipenko
Belarusian State Technological University
Belarus
Belarus
Osipenko Maria A. – Engineer
13a, Sverdlov Str., 220006, Minsk
I. I. Kurilo
Belarusian State Technological University
Belarus
Belarus
Kurilo Irina I. – Ph. D. (Chemistry), Associate Professor,
Head of the Department
13a, Sverdlov Str., 220006, Minsk
A. R. Tsyhanau
International Institute of Management and Entrepreneurship
Belarus
Belarus
Tsyhanau Aliaksandr R. – Academician, D. Sc. (Agrarian), Ph. D. (Chemistry), Professor, Rector
1/3, Slavinsky Str., 220086, Minsk
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