Anodization of niobium in sulphuric acid media

  title={Anodization of niobium in sulphuric acid media},
  author={M. A. Biason Gomes and Sandra A. Onofre and S. Juanto and Luis O.S. Bulh{\~o}es},
  journal={Journal of Applied Electrochemistry},
Niobium oxide films of different thicknesses can be produced on niobium electrodes by anodic polarization. The films produced by a galvanostatic method show different interference colours following the expected theoretical succession of colours. An electrical breakdown was observed which showed a significant dependence of the electrolyte concentration and current density. The relationship between the colour and the current density during the anodization of niobium samples are reported for… Expand
Studies on the electrochemical deposition of niobium oxide
Various strategies for the electrodeposition of niobium oxide from both non-aqueous and aqueous solution are explored. The methods used were based on the electrochemical manipulation of the pH whichExpand
Influence of electropolishing and anodic oxidation on morphology, chemical composition and corrosion resistance of niobium.
  • Maciej Sowa, K. Greń, +9 authors W. Simka
  • Materials Science, Medicine
  • Materials science & engineering. C, Materials for biological applications
  • 2014
The work presents results of the studies performed on electropolishing of pure niobium in a bath that contained: sulphuric acid, hydrofluoric acid, ethylene glycol and acetanilide, which led to the growth of barrier-like oxide layers, which were enriched in phosphorus species. Expand
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The Mechanism of Electropolishing of Niobium in Hydrofluoric-Sulfuric Acid Electrolyte
Niobium surfaces are commonly electropolished in an effort to obtain optimal smoothness for high-field superconducting radio-frequency cavity applications. We report the use of controlledExpand
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Anodic dissolution of tantalum and niobium in acetone solvent with halogen additives for electrochemical synthesis of Ta2O5 and Nb2O5 thin films
Abstract Tantalum(V) and niobium(V) oxide films, which are typically difficult to prepare by electrochemical methods using aqueous solutions, are easily fabricated in an acetone bath using Ta and NbExpand


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Anion impurities in anodic oxide films on zirconium
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