SciELO - Scientific Electronic Library Online

 
vol.8 issue2Effect of molybdate on phosphating of Nd-Fe-B magnets for corrosion protectionCorrosion performance of Al-Si-Cu hypereutectic alloys in a synthetic condensed automotive solution author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

Share


Materials Research

Print version ISSN 1516-1439On-line version ISSN 1980-5373

Abstract

SILVA, Ariadne de Souza et al. Electrochemical behavior of steel-FeNbC composites used in the production of oxygen. Mat. Res. [online]. 2005, vol.8, n.2, pp.151-153. ISSN 1516-1439.  https://doi.org/10.1590/S1516-14392005000200010.

The electrocatalytic properties of steel-FeNbC composites were evaluated after potentiostatic ageing with the purpose of establishing the potential use of such materials as electrodes for the industrial production of oxygen. The effect of processing parameters, involved in the production of the composites by powder metallurgy, such as milling conditions and compaction pressure, on the performance of the electrodes was also studied. The electrodes were characterized according to their electrical resistance in NaOH 1M solution, considering that the purpose of the application requires this value to be ~ 0.5 W.cm2. This parameter was evaluated from repetitive electrochemical measurements carried out from 0.7 V to 1.5 V (vs. Ag/AgCl) by electrode anodization. Changes in the electrochemical behavior of the electrodes, especially concerning the O2 evolution in alkaline medium, were studied as a function of the applied potential. The results revealed that the electrocatalytic activity of the electrodes increased upon ageing, probably as a consequence of the growth of oxide layers and/or increase in the conductivity of the material, resulting in current gain and corresponding decrease in the polarization resistance to 0.75 W cm2.

Keywords : metal-ceramic composites; niobium carbide; oxygen evolution; electrochemistry.

        · text in English     · English ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License