Thermodynamic study of BaCuO[sub 2] and BaCu[sub 2]O[sub 2]

Journal Article · Wed Jun 01 00:00:00 EDT 1994 · Metallurgical Transactions, B (Process Metallurgy); (United States)

OSTI ID:7108141

Shimpo, Ryokichi; Nakamura, Yasushi ^[1]

---

1. Univ. of Tokyo (Japan). Faculty of Engineering

The Gibbs energy changes for the syntheses of the interceramic compounds of BaCuO[sub 2] and BaCu[sub 2]O[sub 2] were investigated as a basic study in the Y-Ba-Cu-O system that includes a superconductor, YBa[sub 2]Cu[sub 3]O[sub 6.5+x]. For the compound BaCuO[sub 2], thermogravimetry with CO[sub 2[minus]]O[sub 2[minus]]N[sub 2] gas mixtures was employed, and equilibrium temperatures were determined at which CO[sub 2] partial pressures in the gas mixtures were equilibrated with mixed powder of BaCuO[sub 2], CuO, and BaCO[sub 3]. The Gibbs energy change for the reaction of BaCO[sub 3] + CuO = BaCuO[sub 2] + CO[sub 2] was determined from the relation between CO[sub 2] partial pressure and equilibrium temperature, taking into consideration the effect of CO[sub 2] dissolution in BaCuO[sub 2]. For the study on BaCu[sub 2]O[sub 2], electromotive force (emf) measurement using yttria-stabilized zirconia solid electrolyte was conducted. A technique using two cells was applied to the emf measurement for minimizing the effect of dispersion of oxygen from samples, and the Gibbs energy change for the reaction of BaCuO[sub 2] + CuO = BaCu[sub 2]O[sub 2] + 1/2O[sub 2] was decided from the measured O[sub 2] partial pressure.

• OSTI ID: 7108141
• Journal Information: Metallurgical Transactions, B (Process Metallurgy); (United States), Vol. 25:3; ISSN 0360-2141
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM COMPOUNDS
THERMODYNAMIC PROPERTIES
CUPRATES
BARIUM CARBONATES
BARIUM OXIDES
CARBON DIOXIDE
CERAMICS
COPPER OXIDES
EXPERIMENTAL DATA
THERMAL GRAVIMETRIC ANALYSIS
YTTRIUM OXIDES
ALKALINE EARTH METAL COMPOUNDS
CARBON COMPOUNDS
CARBON OXIDES
CARBONATES
CHALCOGENIDES
CHEMICAL ANALYSIS
COPPER COMPOUNDS
DATA
GRAVIMETRIC ANALYSIS
INFORMATION
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
QUANTITATIVE CHEMICAL ANALYSIS
THERMAL ANALYSIS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties