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Defect chemistry and transport properties of BaxCe0.85M0.15O3-δ

Published online by Cambridge University Press:  03 March 2011

J. Wu ,
L.P. Li ,
W.T.P. Espinosa  and
S.M. Haile
J. Wu*
Affiliation:
Material Science, California Institute of Technology, Pasadena, California 91125
L.P. Li
Affiliation:
Material Science, California Institute of Technology, Pasadena, California 91125
W.T.P. Espinosa
Affiliation:
Material Science, California Institute of Technology, Pasadena, California 91125
S.M. Haile
Affiliation:
Material Science, California Institute of Technology, Pasadena, California 91125
*
a)Address all correspondence to this author.e-mail: jwu@caltech.edu
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Abstract

The site-incorporation mechanism of M3+ dopants into A2+B4+O3 perovskites controls the overall defect chemistry and thus their transport properties. For charge-balance reasons, incorporation onto the A2+-site would require the creation of negatively charged point defects (such as cation vacancies), whereas incorporation onto the B4+-site is accompanied by the generation of positively charged defects, typically oxygen vacancies. Oxygen-vacancy content, in turn, is relevant to proton-conducting oxides in which protons are introduced via the dissolution of hydroxyl ions at vacant oxygen sites. We propose here, on the basis of x-ray powder diffraction studies, electron microscopy, chemical analysis, thermal gravimetric analysis, and alternating current impedance spectroscopy, that nominally B-site doped barium cerate can exhibit dopant partitioning as a consequence of barium evaporation at elevated temperatures. Such partitioning and the presence of significant dopant concentrations on the A-site negatively impact proton conductivity. Specific materials examined are BaxCe0.85M0.15O3-δ (x = 0.85 - 1.20; M = Nd, Gd, Yb). The compositional limits for the maximum A-site incorporation are experimentally determined to be: (Ba0.919Nd0.081)(Ce0.919Nd0.081)O3, (Ba0.974Gd0.026)(Ce0.872Gd0.128)O2.875, and Ba(Ce0.85Yb0.15)O2.925. As a consequence of the greater ability of larger cations to exist on the Ba site, the H2O adsorption and proton conductivities of large-cation doped barium cerates are lower than those of small-cation doped analogs.

Keywords

Ionic conductorDefectsCeramic
Type
Articles
Information
Journal of Materials Research , Volume 19 , Issue 8 , August 2004 , pp. 2366 - 2376
Copyright
Copyright © Materials Research Society 2004

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References

REFERENCES

1.Pena, M.A. and Fierro, J.L.G.Chemical structures and performance of perovskite oxides. Chem. Rev. 101, 1981 (2001).Google Scholar
2.Kendall, K.R., Navas, C., Thomas, J.K. and zurLoye, H.C.Recent developments in perovskite-based oxide ion conductors. Solid State Ionics 82, 215 (1995).CrossRefGoogle Scholar
3.Iwahara, H., Uchida, H., Ono, K. and Ogaki, K.Proton conduction in sintered oxides based on BaCeO3. J. Electrochem. Soc. 135, 529 (1988).CrossRefGoogle Scholar
4.Uchida, H., Maeda, N. and Iwahara, H.Relation between proton and hole conduction in SrCeO3-based solid electrolytes under water-containing atmospheres at high-temperatures. Solid State Ionics 11, 117 (1983).CrossRefGoogle Scholar
5.Yajima, T., Suzuki, H., Yogo, T. and Iwahara, H.Protonic conduction in SrZrO3-based oxides. Solid State Ionics 51, 101 (1992).Google Scholar
6.Kreuer, K.D.Proton-conducting oxides. Annu. Rev. Mater. Res. 33, 333 (2003).CrossRefGoogle Scholar
7.Iwahara, H., Uchida, H. and Morimoto, K.High temperature solid electrolyte fuel cells using perovskite-type oxide based on BaCeO3. J. Electrochem. Soc. 137, 462 (1990).CrossRefGoogle Scholar
8.Iwahara, H., Uchida, H., Ogaki, K. and Nagato, H.Nernstian hydrogen sensor using BaCeO3-based, proton-conducting ceramics operative at 200°C–900°C. J. Electrochem. Soc. 138, 295 (1991).Google Scholar
9.Makovec, D., Samardžija, Z. and Kolar, D.Solid solubility of neodymium in BaCeO3. J. Am. Ceram. Soc. 80, 3145 (1997).CrossRefGoogle Scholar
10.Tsur, Y., Hitomi, A., Scrymgeour, I. and Randall, C.A.Site occupancy of rare-earth cations in BaTiO3. Jpn. J. Appl. Phys. 40, 255 (2001).Google Scholar
11.Shima, D. and Haile, S.M.The influence of cation non-stoichiometry on the properties of undoped and gadolinia-doped barium cerate. Solid State Ionics 97, 443 (1997).Google Scholar
12.Yamada, A. and Chiang, Y.M.Nature of cation vacancies formed to compensate donors during oxidation of barium-titanate. J. Am. Ceram. Soc. 78, 909 (1995).CrossRefGoogle Scholar
13.Brzozowski, E. and Castro, M.S.Defect profile and electrical properties of Nb2O5-doped BaTiO3 materials. J. Mater. Sci. Mater. Electron. 14, 471 (2003).CrossRefGoogle Scholar
14.Ma, G., Shimura, T. and Iwahara, H.Simultaneous doping with La3+ and Y3+ for Ba2+ and Ce4+-sites in BaCeO3 and ionic conduction. Solid State Ionics 120, 51 (1999).CrossRefGoogle Scholar
15.Buscaglia, M.T., Buscaglia, V. and Viviani, M.Atomistic simulation of dopant incorporation in barium titanate. J. Am. Ceram. Soc. 84, 376 (2001).CrossRefGoogle Scholar
16.Davies, R.A., Islam, M.S. and Gale, J.D.Dopant and proton incorporation in perovskite-type zirconates. Solid State Ionics 126, 323 (1999).CrossRefGoogle Scholar
17.Agarwal, V. and Liu, M.Preparation of barium cerate-based thin films using a modified Pechini process. J. Mater. Sci. 32, 619 (1997).Google Scholar
18.Diffraction, I.U.C.R. Powder: 22, 21 (1997)Google Scholar
19.Knight, K.S. and Bonanos, N.Space group and lattice constants for barium cerate and minor corrections to the crystal structures of BaCe0.9Y0.1O2.95 and BaCe0.9Gd0.1O2.95. J. Mater. Chem. 4, 899 (1994).CrossRefGoogle Scholar
20.Armstrong, J.T.CITZAF - A package of correction programs for the quantitative electron microbeam x-ray-analysis of thick polished materials, thin-films, and particles. Microbeam Anal. 4, 177 (1995).Google Scholar
21.Boukamp, B.B. Equivalent Circuit, University of Twente, The Netherlands (1988)Google Scholar
22.Kruth, A. and Irvine, J.T.S.Water incorporation studies on doped barium cerate perovskite. Solid State Ionics 162–163, 83 (2003).Google Scholar
23.Haile, S.M., West, D.L. and Campbell, J.The role of microstructure and processing on the proton conducting properties of gadolinium-doped barium cerate. J. Mater. Res. 13, 1576 (1998).CrossRefGoogle Scholar
24.Shannon, R.D.: Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crysta. A 32, 751 (1976).Google Scholar
25.Mogensen, M., Lybye, D., Bonanos, N., Hendriksen, P.V. and Poulsen, F.W.: The Effect of Lattice Stress In Ion Conducting Fluorites And Perovskites. Electrochemical Society Proceedings 2001 28, 15 (2002).Google Scholar