Hostname: page-component-76fb5796d-vvkck Total loading time: 0 Render date: 2024-04-26T03:27:33.141Z Has data issue: false hasContentIssue false
  • English
  • Français

Co3O4 Epitaxial Formation on CoO(100)

Published online by Cambridge University Press:  21 February 2011

G. A. Carson ,
M. H. Nassir  and
M. A. Langell
G. A. Carson
Affiliation:
Department of Chemistry, University of Nebraska, Lincoln, Nebraska, 68588–0304, USA
M. H. Nassir
Affiliation:
Department of Chemistry, University of Nebraska, Lincoln, Nebraska, 68588–0304, USA
M. A. Langell
Affiliation:
Department of Chemistry, University of Nebraska, Lincoln, Nebraska, 68588–0304, USA
Get access

Abstract

Co3O4 epitaxies grow readily on cobalt monoxide substrates under a wide range of oxidizing pretreatment conditions. The nucleation and growth of Co3O4 on CoO(lOO) have been investigated by XPS, HREELS and LEED. Both rocksalt CoO and spinel Co3O4 share the geometric characteristic of closest packed lattice O2+ with oxygen to oxygen distances that match to within 5%. We propose a mechanism whereby the Co2+ move from octahedral CoO(100) surface sites to bridging O2- -O2-, positions that correspond to tetrahedral Co2+ sites in the spinel. Oxygen added to the surface finds its way into the near-surface region both as lattice O2-, chemically indistinguishable in CoO and Co3O4, and as excess surface oxygen. The excess oxygen, which gives an XPS binding energy of 531.6 eV and a HREELS signature at 137 meV (1100 cm-1) identifies it as a superoxo species. This species can be added and removed reversibly from the surface by annealing under oxidizing/UHV reducing conditions.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 355: Symposium B1 – Evolution of Thin-Film and Surface Structure and Morphology , 1994 , 163
Copyright
Copyright © Materials Research Society 1995

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Henrich, V.E., Surface and Near-Surface Chemistry of Oxide Materials, edited by Dufour, L.C. and Nowotny, J. (Elsevier Science Publishers, New York, 1987), p. 23.Google Scholar
2. Satterfield, C.N., Heterogeneous Catalysis in Industrial Practice, 2nd ed. (McGraw-Hill, Inc., New York, 1991), p. 319.Google Scholar
3. Shen, Z.-X., Allen, J.W., Lindberg, P.A.P., Dessau, D.S., Wells, B.O., Borg, A., Ellis, W., Kang, J.S., Oh, S.-J., Lindau, I. and Spicer, W.E., Phys. Rev., B 42, 1817 (1990).Google Scholar
4. Henrich, V.E., Adsorption on Ordered Surfaces of Ionic Solids and Thin Films, edited by Freund, H.-J. and Umbach, E. (Springer-Verlag, New York, 1993), 125.Google Scholar
5. Brundle, C.R., Chuang, T.J. and Rice, D.W., Surface Sci., 60, 286 (1976).Google Scholar
6. Oku, M. and Sato, Y., Appl. Surface Sci., 55, 37 (1992).Google Scholar
7. Klingenberg, B., Grellner, F., Borgmann, D. and Wedler, G., Surface Sci., 296, 374 (1993).Google Scholar
8. Jnioui, A., Alnot, M., Ehrhardt, J.J., Amariglio, A. and Amariglio, H., J. Chim. Phys., 83, 323 (1986).Google Scholar
9. Escalona-Platero, E., Spoto, G., Coluccia, S. and Zecchina, A., Langmuir, 3, 291 (1987).Google Scholar
10. Langell, M.A., Surface Sci., 186, 323 (1987).Google Scholar
11. Nassir, M.H. and Langell, M.A., Solid State Commun., 92, 791 (1994).Google Scholar
12. Tyuliev, G. and Angelov, S., Appl. Surface Sci., 32, 381 (1988).Google Scholar
13. Scofield, J.H., J. Electron Spectrosc. Rel. Phenom., 8, 129 (1976).Google Scholar
14. Nassir, M.H. and Langell, M.A., Surface Sci., submitted.Google Scholar
15. Wulser, K.W. and Langell, M.A., Electron, J. Spectrosc. Rel. Phenom., 59, 223 (1992).Google Scholar
16. Grimblot, J., Bonnelle, J.P. and Beaufils, J.P., Electron, J. Spectrosc. Rel. Phenom., 8, 437 (1976).Google Scholar
17. Marcus-Saubat, B., Beaufils, J.P. and Barbaux, Y., J. Chim. Phys., 83, 317 (1986).Google Scholar