TITLE

An EXAFS investigation of molybdate-based conversion coatings

AUTHOR(S)
Wharton, J. A.; Ross, D. H.; Treacy, G. M.; Wilcox, G. D.; Baldwin, K. R.
PUB. DATE
July 2003
SOURCE
Journal of Applied Electrochemistry;Jul2003, Vol. 33 Issue 7, p553
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The composition of molybdate-based conversion coatings on zinc–nickel alloy electrodeposits was examined by extended X-ray absorption fine structure (EXAFS). The absorption spectra from appropriate standards showed distinct differences between the Mo(IV) and Mo(VI) oxidation states. A pre-edge peak was apparent for the various molybdate species and molybdenum trioxide, with the energy and intensity dependent on the coordination of the molybdenum. A shift in the molybdenum K-edge spectra was also evident between Mo(IV) and Mo(VI) compounds. A qualitative analysis revealed that both Mo(IV) and Mo(VI) species were present within the molybdate-based conversion coating, with a significant prevalence of hexavalent molybdenum.
ACCESSION #
16781785

 

Related Articles

  • Properties of zinc coatings electrochemically passivated in sodium molybdate. Akulich, N.; Ivanova, N.; Zharskii, I.; Jönsson‐Niedziółka, M. // Surface & Interface Analysis: SIA;Dec2018, Vol. 50 Issue 12/13, p1310 

    Molybdenum compounds are considered to be promising, environmentally friendly substances for passivation of zinc coatings. Conversion coatings on electroplated zinc coatings obtained by cathodic polarization of a solution of molybdate of sodium with the addition of phosphoric acid are studied....

  • Studies on nanocrystalline zinc coating. Muralindhara, H. B.; Naik, Y. Arthoba // Bulletin of Materials Science;2008, Vol. 31 Issue 4, p585 

    Nano zinc coatings were deposited on mild steel by electrodeposition. The effect of additive on the morphology of crystal size on zinc deposit surface and corrosion properties were investigated. Corrosion tests were performed for dull zinc deposits and bright zinc deposits in aqueous NaCl...

  • Growth and crystal structure of binary molybdate CsFe(MoO). Bazarov, B. G.; Namsaraeva, T. V.; Klevtsova, R. F.; Anshits, A. G.; Vereshchagina, T. A.; Glinskaya, L. A.; Fedorov, K. N.; Bazarova, Zh. G. // Crystallography Reports;Jul2010, Vol. 55 Issue 4, p591 

    CsFe(MoO) single crystals have been grown by solution-melt crystallization with a charge-to-solvent ratio of 1: 3 (with CsMoO used as a solvent). The crystal structure of this compound has been refined by X-ray diffraction (X8 APEX automatic diffractometer, Mo K radiation, 356 F( hkl), R =...

  • THE DETERMINATION OF INORGANIC PHOSPHATE IN THE PRESENCE OF LABILE ORGANO PHOSPHORUS COMPOUNDS. Ennor, A. H.; Stocken, L. A. // Australian Journal of Experimental Biology & Medical Science;Nov1950, Vol. 28 Issue 6, p647 

    Describes a rapid method for the determination of inorganic phosphate in the presence of certain acid-molybdate labile phosphorus compounds. Contents of separating flasks for determination of time necessary for complete extraction of phosphomolybdic acid; Time necessary for the extraction of...

  • Aromatization of Methane Over Mo-Fe/ZSM-5 Catalysts. Masiero, Sara S.; Marcilio, Nilson R.; Perez-Lopez, Oscar W. // Catalysis Letters;Aug2009, Vol. 131 Issue 1/2, p194 

    Two groups of samples were studied for the aromatization of methane over Mo-Fe/ZSM-5 catalysts. The first group contains fixed loading (5 wt%) and variable Mo/Fe ratio. The second group was prepared with fixed Mo/Fe ratio and variable loading. The samples were characterized by TGA, SBET, XRD,...

  • Friction and wear behavior of several functional coatings under lubricated and elevated temperature conditions. Zhang, R. J.; Li, S. H.; Jin, Y. S. // Journal of Materials Science Letters;Oct2003, Vol. 22 Issue 19, p1365 

    The article examines the friction and wear behavior of several functional coatings under lubricated and elevated temperature conditions. The friction and wear behavior for the molybdenum-sprayed coating, nitrided coating and chromium-plated coating under lubricated and sliding contact conditions...

  • Hot Dipped Zn-Al-Mg-Cu Coating with Improved Mechanical and Anticorrosion Properties. Caizhen Yao; See Leng Tay; Ji Hyun Yang; Tianping Zhu; Wei Gao // International Journal of Electrochemical Science;2014, Vol. 9 Issue 12, p7083 

    Three types of coatings: Zn-0.1 wt.%Cu (G), Zn-5 wt.%Al-0.1 wt.%Cu (ZA) and Zn-5 wt.%Al-1 wt.%Mg-0.1 wt.%Cu (ZAM) were deposited by hot dipping method on mild steel substrates. The phase structure, cross section microstructure, composition, microhardness and corrosion property of the coatings...

  • Evaluation of zinc-rich epoxy paint performance by electrochemical impedance spectroscopy. HAMMOUDA, Nadia; Chadli, H.; Guillemot, G.; Belmokre, K. // Turkish Online Journal of Science & Technology;Oct2013, Vol. 3 Issue 4, p64 

    To improve understanding of Zn-rich coatings for use in the storage reservoirs of oil, such coatings are being examined in the laboratory by the suite of testing techniques: Open Circuit Potential (OCP) (Ecor) measurements , exposure time to verify electrochemical cathodic protection,...

  • Zinc phosphate coatings on non-ferrous substrates. Menke, Joseph // Products Finishing;Dec96, Vol. 61 Issue 3, p78 

    Part III. Focuses on the application of zinc phosphate coatings on cadmium-plated and aluminium substrates. Description of the formulations used; Examination of the effects of the grain refiner on surface of the panels; Inability of calcium-modified zinc phosphating solutions to provide...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics