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Ionics

, Volume 7, Issue 4–6, pp 351–359 | Cite as

Electrical properties of Cr-doped CoO

  • M. Ijjaali
  • K. Kowalski
  • T. Bak
  • B. Dupre
  • C. Gleitzer
  • J. Nowotny
  • M. Rekas
  • C. C. Sorrell
Article

Abstract

This paper reports the results of the electrical conductivity measurements for polycrystalline specimens of undoped and Cr-doped CoO in the ranges of p(O2) (10−5 – 105 Pa) and temperature (1223 – 1373 K). The experimental data are considered in terms of the effect of Cr on semiconducting properties of CoO. It is shown that Cr results in a decrease of the reciprocal of the p(O2) exponent of electrical conductivity, however, the obtained experimental values are substantially lower than those predicted by defect chemistry. The activation energy of the electrical conductivity remains independent of p(O2) and Cr content (at the level of about 0.5 eV) except strongly reduced CoO, at p(O2)=2.10−4 Pa, of which the activation energy is substantially higher. Thermopowervs p(O2) exhibits maximum at p(O2)=10 Pa (except of thermopower data for Cr-doped CoO at the highest temperature). The experimental data are considered in terms of the effect of both p(O2) and Cr on semiconducting properties.

Keywords

Experimental Data Physical Chemistry Analytical Chemistry Activation Energy Electrical Conductivity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. [1]
    P. Kofstad, Diffusion, Non-Stoichiometry and Electrical Conductivity of Binary Metal Oxides, Wiley, New York, 1972.Google Scholar
  2. [2]
    J. Nowotny, M. Rekas, J. Amer. Ceram. Soc.72, 1207 (1989).Google Scholar
  3. [3]
    R. Dieckmann, Z. Physik. Chem., Neue Folge107, 189 (1977).Google Scholar
  4. [4]
    J. Nowotny and M. Rekas, J. Electrochem. Soc.131, 94 (1984).Google Scholar
  5. [5]
    J. Nowotny and M. Rekas, in: Diffusion in Solids and High Temperature Oxidation of Metals (J. Nowotny, Ed.) Trans Tech Publications, Zurich, 1991, p 169.Google Scholar
  6. [6]
    G.H. Meier and R.A. Rapp, Zeitschrift f. Phys. Chem., Neue Folge74 168 (1971).Google Scholar
  7. [7]
    R.A. Perkins and R.A. Rapp, Metall. Trans.4, 193 (1973).Google Scholar
  8. [8]
    J. Nowotny, in: CRC Handbook of Solid State Electrochemistry, P.J. Gellings and H.J.M. Bouwmeester, Eds., Boca Raton, 1997, p. 121.Google Scholar
  9. [9]
    M. Stoneham, Physics Today33, 34 (1980).Google Scholar
  10. [10]
    B. Fisher and D.S. Tannhauser, J. Chem. Phys.44, 1663 (1966).Google Scholar
  11. [11]
    E.M. Logothetis and J.K. Park, Solid State Comm.43, 543 (1982).Google Scholar
  12. [12]
    H.C. Chen and T.O. Mason, J. Am. Ceram. Soc.64, C-130 (1981).Google Scholar
  13. [13]
    J. Nowotny, I. Sikora, J.B. Wagner, Jr., J. Am. Ceram. Soc.65, 192 (1982).Google Scholar

Copyright information

© IfI - Institute for Ionics 2001

Authors and Affiliations

  • M. Ijjaali
    • 1
  • K. Kowalski
    • 2
  • T. Bak
    • 3
  • B. Dupre
    • 1
  • C. Gleitzer
    • 1
  • J. Nowotny
    • 3
  • M. Rekas
    • 3
  • C. C. Sorrell
    • 3
  1. 1.Universite Nancy I, Laboratoire de Chimie du Solide MineralVandoeovre-les-NancyFrance
  2. 2.Surface Spectroscopy Laboratory of the University of Mining and Metallurgy and Joint University Center for Chemical Analysis and Microstructure Research of Jagiellonian UniversityKrakowPoland
  3. 3.Centre for Materials Research in Energy Conversion, School of Materials Science and EngineeringThe University of New South WalesSydneyAustralia

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