Determination of the oxygen content in superconducting and related cuprates using temperature-programmed reduction

Journal Article · Sat Jun 01 04:00:00 EDT 1991 · Journal of Solid State Chemistry; (United States)

DOI:https://doi.org/10.1016/0022-4596(91)90341-E· OSTI ID:5977745

Halasz, I; Jen, Hungwen; Brenner, A; Kao, Sendjaja; Y S, Ng K ^[1]; Shelef, M ^[2]

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1. Wayne State Univ., Detroit, MI (United States)
2. Ford Motor Co., Dearborn, MI (United States)

The oxygen content and reducibilities of four base metal oxides, six nonconducting cuprates, and three superconducting cuprates were investigated by temperature-programmed reduction (TPR) from 30 to 900C. It was shown that the copper, bismuth, and thallium ions of these oxides were reduced to the zero valence state. Thus, TPR is a useful technique for determining the actual oxygen stoichiometry of cuprates. For multiphase Bi{sub 2}CaSr{sub 2}Cu{sub 2}O{sub 8+x} and Tl{sub 2}CaBa{sub 2}Cu{sub 2}O{sub 8+x} superconductors pretreated in air, x was found to be 2 {plus minus} 0.2 and 1 {plus minus} 0.2, respectively. Both values are significantly higher than previously reported. The reduction of superconducting and related cuprates required higher temperatures than CuO, but the reducibility of CuO decreased when it was calcined in air at 940C. The Bi- and Y-based superconducting cuprates exhibited the lowest reducibility among the samples investigated.

• OSTI ID: 5977745
• Journal Information: Journal of Solid State Chemistry; (United States), Journal Name: Journal of Solid State Chemistry; (United States) Vol. 92:2; ISSN JSSCB; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102* -- Chemical & Spectral Procedures
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
BISMUTH COMPOUNDS
BISMUTH OXIDES
CALCIUM COMPOUNDS
CALCIUM OXIDES
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
COPPER COMPOUNDS
COPPER OXIDES
CUPRATES
DATA
ELEMENTS
EVALUATION
EXPERIMENTAL DATA
INFORMATION
NONMETALS
NUMERICAL DATA
OXIDES
OXYGEN
OXYGEN COMPOUNDS
QUANTITATIVE CHEMICAL ANALYSIS
REDUCTION
STOICHIOMETRY
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTORS
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
THALLIUM COMPOUNDS
THALLIUM OXIDES
THERMOMETRIC TITRATION
TITRATION
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES