OATAO - Open Archive Toulouse Archive Ouverte Open Access Week

An electrochemical and surface analytical study of the formation of nanoporous oxides on niobium

Tzvetkov, Bogdan and Bojinov, Martin and Girginov, Assen and Pébère, Nadine An electrochemical and surface analytical study of the formation of nanoporous oxides on niobium. (2007) Electrochimica Acta, vol. 52 (n° 27). pp. 7724-7731. ISSN 0013-4686

[img]
Preview
(Document in English)

PDF (Author's version) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
572kB

Official URL: http://dx.doi.org/10.1016/j.electacta.2006.12.034

Abstract

In the present paper, the anodization of Nb in mixed sulphate + fluoride electrolytes resulting in the formation of a nanoporous oxide film has been studied. Chronoamperometry and electrochemical impedance spectroscopy have been employed to characterise in situ the kinetics of the oxidation process. In addition, the evolution of the layer structure and morphology has been followed by ex situ scanning electron microscopy. Particularly, local electrochemical impedance spectroscopy has been used to discern between the mesoscopic 2D and 3D distributions of time constants at the electrode surface. The similarity between local and global impedance spectra during anodic oxidation of Nb demonstrates the presence of an inherent 3D distribution of the high-frequency time constant, which is interpreted as in-depth variation of the steady state conductivity of the passive film. The experimental and calculational results are discussed in relation to the micro- and nanoscopic structure of the formed oxide.

Item Type:Article
Additional Information:Thanks to Elsevier editor. The definitive version is available at http://www.sciencedirect.com The original PDF of the article can be found at Electrochimica Acta website : http://www.sciencedirect.com/science/journal/00134686
Audience (journal):International peer-reviewed journal
Uncontrolled Keywords:
Institution: Université de Toulouse > Institut National Polytechnique de Toulouse - INPT
Université de Toulouse > Université Paul Sabatier-Toulouse III - UPS
French research institutions > Centre National de la Recherche Scientifique - CNRS
Other partners > University of Chemical Technology and Metallurgy of Sophia (BULGARIA)
Laboratory name:
Statistics:download
Deposited By: Celine Cabaup

Repository Staff Only: item control page