Abstract
We synthesized dense CeO\({2 - x} \) polycrystals of ∼10 nm grain size and characterized their electrical conductivity, in order to determine whether the defect properties of nanocrystalline solids fundamentally differ from those of conventional materials. The nanocrystals exhibit enhanced electronic conductivity, greatly reduced grain boundary impedance, and a heat of reduction more than 2.4 eV lower per oxygen vacancy compared to their coarse-grained counterparts. We propose that defect formation at low energy grain boundary sites is responsible for these properties, and that nanocrystalline oxides represent bulk materials possessing the defect thermodynamics of interfaces.
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H. Gleiter, Progress in Materials Science, 33, 1 (1990); R. Birringer, U. Herr, and H. Gleiter, Trans. Jpn. Inst. Met., 27 suppl., 43 (1986); R.W. Siegel, Ann. Rev. Mater. Sci., 21, 559 (1991).
J. Karch, R. Birringer, and H. Gleiter, Nature, 330, 556 (1987); J. Karch and R. Birringer, Ceramics Int., 16, 291 (1990); M.J. Mayo, R.W. Siegel, A. Narayanasamy, and W.D. Nix, J. Mater. Sci., 5, 1073 (1990).
D.D. Beck and R.W. Siegel, J. Mater. Res., 7, 2840 (1992), A. Tschoepe and J.Y. Ying, p. 781 in Nanophase Materials: Synthesis-Properties-Applications, G.C. Hadjipanayis and R.W. Siegel, eds., (Kluwer Academic Publ., Netherlands, 1994).
F.R.N. Nabarro, p. 75 in Report of a Conference on the Strength of Solids, (The Physical Society, London, 1948); C. Herring, J. Appl. Phys., 21, 437 (1950); R.L. Coble, J. Appl. Phys., 34, 1679 (1963).
C.D. Terwilliger and Y.-M. Chiang, J. Am. Ceram. Soc., 78, 2045 (1995).
S.R. Phillpot, J. Wang, D. Wolb, and H. Gleiter, Mat. Sci. Eng. A204, 76 (1995).
A. Tschoepe, J.Y. Ying, and H.L. Tuller, Sensors and Actuators. B31, 1–4 (1996).
Y.-M. Chiang, E.B. Lavik, I. Kosacki, H.L. Tuller, and J.Y. Ying, Appl. Phys. Lett., 69[2], 185–187 (1996).
H.L. Tuller and A.S. Nowick, J. Electrochem. Soc., 126, 209 (1979).
R. Gerhardt and A.S. Nowick, J. Am. Ceram. Soc., 69, 641 (1986), and R. Gerhardt, A.S. Nowick, M.E. Mochel and I. Dumler, J. Am. Ceram. Soc., 69, 646 (1986).
See for example: J.E. Bauerle. J. Phys. Chem. Solids, 30, 2657 (1969); A. Ioffe, M.V. Inozemtsev, A.S. Lipilin, M.V. Perfilev, and S.V. Karpachov, Phys. Stat. Sol. (a), 30, 87 (1975), S.H. Chu and M.A. Seitz, J. Solid State Chem., 23, 297–314 (1979); N. Bonanos, B.C.H. Steele, and E.P. Butler, p.191 in Impedance Spectroscopy, J.R. MacDonald, ed., (John Wiley and Sons, New York, 1987).
M.J. Verkerk, B.J. Middelhuis, and A.J. Burggraaf, Solid State Ionics, 6, 159 (1982); M. Gödickemeier et al., J. Mat. Res., 9, 1228 (1994); S.P.S. Badwal and S. Rajendran, Solid State Ionics, 70/71, 83 (1994).
M. Aoki, Y.-M. Chiang, I. Kosacki, J.-R. Lee, H.L. Tuller, and Y. Liu, J. Am. Ceram. Soc., 79[5], 1169 (1996).
C.D. Terwilliger and Y.-M. Chiang, Acta Metall. Mater., 43, 319 (1995).
H.L. Tuller and A.S. Nowick, J. Electrochem. Soc., 122, 255 (1975).
R.N. Blumenthal, F.S. Brugner, and J.E. Garnier, J. Electrochem. Soc., 120, 1230 (1973).
H.L. Tuller and A.S. Nowick, J. Phys. Chem. Solids, 38, 859 (1977).
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Lavik, E.B., Kosacki, I., Tuller, H.L. et al. Nonstoichiometry and Electrical Conductivity of Nanocrystalline CeO\({2 - x} \) . Journal of Electroceramics 1, 7–14 (1997). https://doi.org/10.1023/A:1009934829870
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DOI: https://doi.org/10.1023/A:1009934829870