Stable spinel type cobalt and copper oxide electrodes for O2and H2evolutions in alkaline solution

Jingshu Jia, Xinyong Li, Guohua Chen

Research output: Journal article publicationJournal articleAcademic researchpeer-review

28 Citations (Scopus)

Abstract

The stability of one material, Ti/CuxCo3-xO4, as anode and also cathode was investigated for electrolysis of alkaline aqueous solution. The electrodes were prepared by thermal decomposition method with x varied from 0 to 1.5. The accelerated life test illustrated that the electrodes with x = 0.3 nominally showed the best performance, with a total service life of 1080 h recorded in 1 M NaOH solution under alternating current direction at 1 A cm-2and 35 °C. The effects of copper content in electrode coating were examined in terms of electrode stability, surface morphology, coating resistivity and coating compositions. The presence of Cu in the spinel structure of Co3O4could significantly enhance the electrochemical and physicochemical properties. The trends of crystallographic properties and surface morphology have been analyzed systemically before, during and after the electrodes were employed in alkaline electrolysis. The oxygen evolution would lead to the consumption of the coating material and the progressive cracking of the coating. Along with hydrogen evolution, cobalt oxide could be reduced to metal Co and Co(OH)2with particle sizes changed to smaller values in crystal and/or amorphous form at the cathode. The formation of Co is the key process for this electrode to serve as both anode and cathode. It is also the main reason leading to the eventual failure of the electrodes.
Original languageEnglish
Pages (from-to)8197-8206
Number of pages10
JournalElectrochimica Acta
Volume55
Issue number27
DOIs
Publication statusPublished - 30 Nov 2010
Externally publishedYes

Keywords

  • Dimensionally stable anode
  • Electroflotation
  • Electrolysis
  • H evolution 2
  • O evolution 2

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Electrochemistry

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