Phase diagram of nonstoichiometric 10 mol% Gd{sub 2}O{sub 3{minus}}doped cerium oxide determined from specific heat measurements

Journal Article · Sat Jul 01 04:00:00 EDT 1995 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1006/jssc.1995.1290· OSTI ID:146443

Stelzer, N; Noelting, J ^[1]

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1. Universitaet Goettingen (Germany)

The phase diagram for nonstoichiometric 10 mol%Gd20{sub 3{minus}}doped cerium oxide, Ce{sub 0.818}Gd{sub 0.182}O{sub 1.909{minus}y}, was determined from specific heat measurements in the temperature range 300-1250 K and composition range Ce{sub 0.818}Gd{sub 0.182}O{sub 1.909}-Ce{sub 0.818}Gd{sub 0.182}O{sub 1.731}, using a controlled diabatic scanning calorimeter. No phase transition was found in this temperature range for the composition Ce{sub 0.818}Gd{sub 0.182}O{sub l.909}. The specific heat measurements reveal phase transitions for the composition range Ce{sub 0.818}Gd{sub 0.182}O{sub l.859}-Ce{sub 0.818}Gd{sub 0.182}0{sub 1.731}. A phase diagram is constructed which shows a miscibility gap. The maximum of the miscibility gap occurs at the composition Ce{sub 0.818}Gd{sub 0.182}O{sub 1.788} and T = 939 K. The phase diagrams of nonstoichiometric CeO{sub 2{minus}x} and Ce{sub 0.818}Gd{sub 0.182}O{sub 1.909{minus}y} are compared and discussed in detail.

• Sponsoring Organization: USDOE
• OSTI ID: 146443
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 2 Vol. 117; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CERIUM OXIDES
GADOLINIUM OXIDES
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
SPECIFIC HEAT
STOICHIOMETRY
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K