abstract
Corrosion protection efficiencies of Layered Double Hydroxide (LDH) conversion coatings on zinc were studied. As-prepared LDH coatings contained nitrate anions that were exchanged for vanadate ones. Corrosion inhibitive properties of the LDH coatings were studied by electrochemical impedance spectroscopy (EIS) and scanning vibrating electrode technique (SVET) techniques in 0.05 M NaCl solutions. Electron microscopy, X-ray diffraction and release studies were employed to understand the mechanism of zinc protection. The LDH/vanadate system displayed about 20-fold increase in impedance and smaller local ionic currents compared to bare zinc. The protection was attributed to the partial release of vanadate anions from the LDH.
keywords
LAYERED DOUBLE HYDROXIDES; ZN-AL; GALVANIZED STEEL; LOCALIZED CORROSION; ORGANIC COATINGS; INHIBITION; VANADATE; PRODUCTS; NITRATE; ANIONS
subject category
Materials Science; Metallurgy & Metallurgical Engineering
authors
Yasakau, KA; Kuznetsova, A; Maltanava, HM; Poznyak, SK; Ferreira, MGS; Zheludkevich, ML
our authors
Alena Kuznetsova
Research Fellowship
Kiryl Yasakau
Assistant Researcher
Mário Guerreiro Silva Ferreira
Retired Professor
Mikhail Zheludkevich
Invited Principal ResearcherProjects
Projeto de Investigação Exploratória: Kyril Yasakao (IF/01284/2015)
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
acknowledgements
KY acknowledges the Portuguese Foundation for Science and Technology for the researcher grants (IF/01284/2015 and 2021.00842.CEECIND) . This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by National funds through the FCT/MCTES (PIDDAC) . This work was supported by the European project (H2020-MSCA-RISE-2018-823942-FUNCOAT) . The authors thank Zinaida Shakel for XRD measurements.r CEECIND) . This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MCTES (PIDDAC) . This work was supported by the European project (H2020-MSCA-RISE-2018-823942-FUNCOAT) . The authors thank Zinaida Shakel for XRD measurements.