Oxidation of Metals

, Volume 24, Issue 1–2, pp 17–27 | Cite as

Oxidation of copper and reduction of Cu2O in an environmental scanning electron microscope at 800°C

  • T. A. Ramanarayanan
  • J. Alonzo


The present study reports on the in situ oxidation of copper to Cu2O and subsequent reduction to metallic copper in an environmental scanning electron microscope. The oxidation was carried out at approximately 125 μm oxygen pressure while the reduction was done at the same pressure using H2 gas. The first visible signs of oxidation occurred in about 2 min: submicron size nuclei of Cu2O formed randomly on the metal surface. No preferred nucleation along grain boundaries could be observed. The surface was completely covered with Cu2O in about 30 min of oxidation time, the final average grain size of Cu2O being approximately 3 μm. The reduction kinetics of Cu2O were slower than the oxidation kinetics, the first visible copper nuclei appearing only after about 6 min of reduction. A reduction mechanism is suggested where the diffusion of copper vacancies from the copper particle-Cu2O interface to the Cu2O-H2 interface limits the overall kinetics. Based on this assumption, a copper supersaturation corresponding to a copper activity of 1.0005 in Cu2O has been calculated.

Key words

nucleation diffusion supersaturation 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    G. C. Wood and B. Chattopadhyay,J. Inst. Met. 98, 117 (1970).Google Scholar
  2. 2.
    M. D. Sanderson and J. C. Sculby,Corr. 25, 291 (1969).Google Scholar
  3. 3.
    B. Chattopadhyay and G. C. Wood,Oxid. Met. 2, 373 (1970).Google Scholar
  4. 4.
    G. C. Wood and B. Chattopadhyay,Corr. Sci. 1, 471 (1970).Google Scholar
  5. 5.
    N. S. McIntyre, D. G. Zetaruk, and D. Owen,Appl. Surf. Sci. 2, 55 (1978).Google Scholar
  6. 6.
    G. C. Allen, P. M. Tucker, and R. K. Wild,J. Chem. Soc., Farad. Trans. 2, 74, 1126 (1978).Google Scholar
  7. 7.
    G. M. Raynaud, W. A. T. Clark, and R. A. Rapp,Met. Trans. A 15A, 573 (1984).Google Scholar
  8. 8.
    R. Rapp,Met. Trans. A 15A, 765 (1984).Google Scholar
  9. 9.
    C. Wagner,Z. Phys. Chem. B 21, 25 (1933).Google Scholar
  10. 10.
    N. Cabrera and N. F. Mott,Rep. Prog. Phys. 12, 163 (1948–49).Google Scholar
  11. 11.
    N. F. Mott,Trans. Faraday Soc. 43, 429 (1947).Google Scholar
  12. 12.
    C. Wagner and H. Hammen,J. Phys. Chem. 1340, 197 (1938).Google Scholar
  13. 13.
    C. Wagner and K. Gruenewald,J. Phys. Chem. B 40, 455 (1938).Google Scholar
  14. 14.
    C. S. Giggins and F. S. Pettit,Trans. Met. Soc. AIME 245, 2509 (1969).Google Scholar
  15. 15.
    H. Schmalzried and C. Wagner,Trans. AIME 227, 539 (1963).Google Scholar
  16. 16.
    C. Wagner, inSteel Making, the Chipman Conference, J. F. Elliott, ed. (M.I.T. Press, 1965), p. 19.Google Scholar
  17. 17.
    W. J. Moore and B. Selikson,J. Chem. Phys. 19, 1539 (1951);20, 927 (1952).Google Scholar
  18. 18.
    F. A. Krögen and H. J. Vink,Solid State Phys. 3, 307 (1956).Google Scholar

Copyright information

© Plenum Publishing Corporation 1985

Authors and Affiliations

  • T. A. Ramanarayanan
    • 1
  • J. Alonzo
    • 2
  1. 1.Exxon Research and Engineering CompanyAnnandale
  2. 2.Microscopy Research Laboratories Inc.North Branch

Personalised recommendations