Ceria-based solid electrolytes

doi:10.1016/0167-2738(95)00229-4

Solid State Ionics

Volume 83, Issues 1–2, January 1996, Pages 1-16

https://doi.org/10.1016/0167-2738(95)00229-4 Get rights and content

Abstract

Ceria-based solid electrolytes are reviewed in terms of electrical conductivity, diffusivity and transference number. The electrical conductivity and diffusion constants of various fluorite compounds are compared and those of ceria-based oxides are almost the highest among these fluorite oxides. The electrical conductivity of doped ceria is much dependent on the kind and the concentration of dopants. The reason for this behavior and a guideline to obtain more electrically conductive materials are discussed. The effect of sample preparation on the electrical conductivity is described in terms of the character of raw materials, impurities and the sintering condition. The factors to determine the transference number and the methods to increase the transference number at low oxygen pressures are also discussed.

References (50)

R.M. Dell et al.
J.A. Kilner et al.
Solid State Ionics
(1982)
M.A. Panhans et al.
Solid State Ionics
(1993)
H. Arai et al.
Solid State Ionics
(1986)
H. Yahiro et al.
Solid State Ionics
(1989)
K. Eguchi et al.
Solid State Ionics
(1992)
R. Gerhardt-Anderson et al.
Solid State Ionics
(1981)
Da Yu Wang et al.
Solid State Ionics
(1981)
J.A. Kilner
Solid State Ionics
(1983)
J.A. Kilner et al.
Solid State Ionics
(1982)

K. Fuda et al.

J. Phys. Chem. Solids

(1984)

J.G. Allpress et al.

J. Solid State Chem.

(1975)

M. Beniere et al.

J. Phys. Chem. Solids

(1979)

A.B. Auskern et al.

J. Nucl. Mater.

(1961)

R.L. Deaton et al.

J. Inorg. Nucl. Chem.

(1973)

K.C. Kim et al.

J. Nucl. Mater.

(1981)

A.S. Bayoglu et al.

J. Nucl. Mater.

(1979)

P. Contamin et al.

J. Nucl. Mater.

(1972)

D.L. Maricle et al.

Solid State Ionics

(1992)

B.C.H. Steele

J.A. Kilner et al.

H. Yahiro et al.

J. Mater. Sci.

(1988)

G.B. Balazs et al.

R.T. Dirstine et al.

J. Electrochem. Soc.

(1979)

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ReviewCeria-based solid electrolytes

Abstract

Solid State Ionics

Solid State Ionics

Solid State Ionics

Solid State Ionics

Solid State Ionics

Solid State Ionics

Solid State Ionics

Solid State Ionics

Solid State Ionics

J. Phys. Chem. Solids

J. Solid State Chem.

J. Phys. Chem. Solids

J. Nucl. Mater.

J. Inorg. Nucl. Chem.

J. Nucl. Mater.

J. Nucl. Mater.

J. Nucl. Mater.

Solid State Ionics

J. Mater. Sci.

J. Electrochem. Soc.

Review
Ceria-based solid electrolytes