Hydrothermal synthesis and properties of mixed conducting Ce{sub 1{minus}x}Tb{sub x}O{sub 2{minus}{delta}} solid solutions

Journal Article · Mon Feb 01 04:00:00 EST 1999 · Chemistry of Materials

DOI:https://doi.org/10.1021/cm980682d· OSTI ID:329073

Shuk, P; Greenblatt, M; Croft, M ^[1]

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1. Rutgers-the State Univ. of New Jersey, Piscataway, NJ (United States)

The structure, thermal expansion coefficients, and ionic and electronic conductivities of Ce{sub 1{minus}x}Tb{sub x}O{sub 2{minus}{delta}} (x = 0--0.30) solid solutions, prepared hydrothermally for the first time, were investigated. The uniformly small particle size (33--40 nm) of the hydrothermally prepared materials allows sintering of the samples into highly dense ceramic pellets at 1300--1400 C, a significantly lower temperature, compared to that at 1600--1650 C required for samples prepared by solid-state techniques. X-ray absorption near edge spectroscopy was used for the identification of Tb{sup 3+}/Tb{sup 4+} ions. The maximum of total conductivity was found at x = 0.25 ({sigma}{sub 700 C} = 2.1 {times} 10{sup {minus}2} S/cm, E{sub a} = 0.49 eV) with electronic contribution to the total conductivity around {approximately}50% at 600--700 C. The conductivity becomes more ionic with decreasing Tb substitution. The thermal expansion coefficients, determined from high-temperature X-ray diffraction data, are 11.7 {times} 10{sup {minus}6} K{sup {minus}1} for CeO{sub 2} and slowly decrease with increasing Tb substitution (10.8 {times} 10{sup {minus}6} K{sup {minus}1} at x = 0.30).

• OSTI ID: 329073
• Journal Information: Chemistry of Materials, Journal Name: Chemistry of Materials Journal Issue: 2 Vol. 11; ISSN CMATEX; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CERIUM OXIDES
CRYSTAL STRUCTURE
ELECTRIC CONDUCTIVITY
HYDROTHERMAL SYNTHESIS
SINTERING
SOLID SOLUTIONS
TERBIUM OXIDES
THERMAL EXPANSION
X-RAY DIFFRACTION