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The preparation and electrical properties of TiO2−xFx

Published online by Cambridge University Press:  31 January 2011

Tadashi Endo
Affiliation:
Department of Applied Chemistry, Faculty of Engineering, Tohoku University, Aoba, Sendai, Miyagi 980, Japan
Naoki Morita
Affiliation:
Department of Applied Chemistry, Faculty of Engineering, Tohoku University, Aoba, Sendai, Miyagi 980, Japan
Tsugio Sato
Affiliation:
Department of Applied Chemistry, Faculty of Engineering, Tohoku University, Aoba, Sendai, Miyagi 980, Japan
Masahiko Shimada*
Affiliation:
Department of Applied Chemistry, Faculty of Engineering, Tohoku University, Aoba, Sendai, Miyagi 980, Japan
*
a)The author to whom all correspondence, should be addressed.
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Abstract

The substitution of fluorine for oxygen in TiO2 was investigated by the reaction of Ti2O3, TiO2, and TiF3 under conditions of 4–6.5 GPa and 700–1400°C. The single phase of TiO2−x Fx solid solution was obtained in the region of 0≤x≤0.7. According to the x-ray diffraction data, the a and c axes of the rutile-type structure linearly increased with increasing fluorine content. The electrical resistivities of TiO2−x Fx were in the range from 10 Ω cm for x = 0.3 to 850 Ω cm for x = 0.7 at 300 K and the relationship between In ρ and 1000/T was linear. The activation energies were estimated to be from 0.17 eV at x = 0.3 to 0.28 eV at x = 0.7. Also, the thermoelectric powers at room temperature changed from 250μV/K to + 50 μV/K. The mechanism of electric conduction was discussed on the basis of the extended band model of rutile.

Type
Articles
Copyright
Copyright © Materials Research Society 1988

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References

1Johnson, G. H., J. Am. Chem. Soc. 36, 97 (1953).Google Scholar
2Chamberland, B. L. and Sleight, A. W., Solid State Commun. 5, 765 (1967).CrossRefGoogle Scholar
3Holloway, J. H. and Laycock, D.Advances in Inorganic Chemistry and Radiochemistry, edited by Emeleus, H. J. and Shapre, A. G. (Academic, London, 1984), Vol. 28, p. 73.Google Scholar
4Chamberland, B. L., Sleight, A. S., and Cloud, W. H.J. Solid State Chem. 2, 49 (1970).CrossRefGoogle Scholar
5Fukunaga, O., Yamaoka, S., Endoh, T., Akaishi, M., and Kanda, H., High Pressure Science and Technology, edited by Timmerhaus, K. D. and Barber, M. S. (Plenum, New York, 1979), Vol. 1, p. 846.CrossRefGoogle Scholar
6Merwin, H. E., Am. J. Sci. 28, 119 (1969).Google Scholar
7Hashitani, H., Yoshida, H., and Muto, H., Jpn. Analyst 16, 44 (1967).CrossRefGoogle Scholar
8Ahrens, L. H., Geochim. Cosmochim. Acta 2, 155 (1952).CrossRefGoogle Scholar
9Grant, F. A., Rev. Mod. Phys. 31, 646 (1959).CrossRefGoogle Scholar
10Hurd, C. M., Philos. Mag. B 50, L29 (1984).Google Scholar
11Breckeridge, R. G. and Manghnani, M. H., Geophys. Res. Lett. 5, 491 (1953).Google Scholar
12Goodenough, J. B., Bull. Soc. Chim. Fr. 1965, 1200.Google Scholar