Effects of cation substitution on electrical and thermal transport properties of YCrO/sub 3/ and LaCrO/sub 3/

Journal Article · Wed Apr 01 04:00:00 EST 1987 · J. Am. Ceram. Soc.; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1987.tb04979.x· OSTI ID:5530221

Weber, W J; Griffin, C W; Bates, J L

High-temperature electrical conductivity, Seebeck coefficient, and thermal conductivity measurements were used to study the effects of different cation substituents on electric and thermal transport in YCrO/sub 3/ and LaCrO/sub 3/. The substitution of divalent Ca and Sr for Y and La, respectively, resulted in the formation of small polarons as charged carriers. The additional substitution of Mn for Cr resulted in the formation of a second charge carrier associated with the Mn. The electrical conductivity results were consistent with thermally activated transport by hopping of a temperature-independent carrier concentration. The activation energies were 0.20 and 0.12 eV for (Y,Ca)CrO/sub 3/ and (La,Sr)CrO/sub 3/, respectively, and increased to about 0.50 eV with the substitution of Mn for Cr. The Seebeck coefficient increased linearly with temperature and decreased with substituent concentration for both (Y,Ca)CrO/sub 3/ and (La,Sr)CrO/sub 3/. The substitution of Mn for Cr resulted in a Seebeck coefficient with a more complex dependence on temperature and substituent concentration. The thermal conductivity did not change significantly with either cation substitution or temperature.

• Research Organization: Battelle, Pacific Northwest Labs., Richland, WA 99352
• OSTI ID: 5530221
• Journal Information: J. Am. Ceram. Soc.; (United States), Journal Name: J. Am. Ceram. Soc.; (United States) Vol. 70:4; ISSN JACTA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ACTIVATION ENERGY
CATIONS
CHALCOGENIDES
CHARGED PARTICLES
CHROMIUM COMPOUNDS
CHROMIUM OXIDES
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ENERGY
IONS
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SEEBECK EFFECT
THERMAL CONDUCTIVITY
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES