Anodization of niobium in sulphuric acid media

@article{Gomes1991AnodizationON,
  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},
  year={1991},
  volume={21},
  pages={1023-1026}
}
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.
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TLDR
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
Modification of niobium surfaces using plasma electrolytic oxidation in silicate solutions
Herein, a study of the plasma electrolytic oxidation (PEO) of niobium in an anodising bath composed of potassium silicate (K2SiO3) and potassium hydroxide (KOH) is reported. The effects of the K2SiO3Expand
Influence of the forming electrolyte on the electrical properties of tantalum and niobium oxide films: an EIS comparative study
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OBTAINING NIOBIUM OXIDES IN ACETIC ACID WITH ADDITION OF HF
During anodizing, the chemical attack of hydrofluoric acid (HF) electrolytes on niobium can promote the formation of oxides with porous structures. However, this chemical attack can also cause anExpand
Anodic dissolution of tantalum and niobium in acetone solvent with halogen additives for electrochemical synthesis of Ta2O5 and Nb2O5 thin films
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