Effect of Starting Particle Size and Vacuum Processing on the YBa2Cu3Ox Phase Formation

被引：16

作者：

Grader, G. S. ^{[1
]}

Gallagher, P. K. ^{[1
]}

Fleming, D. A. ^{[1
]}

机构：

[1] AT&T Bell Labs, Murray Hill, NJ 07974 USA

来源：

CHEMISTRY OF MATERIALS | 1989年 / 1卷 / 06期

关键词：

D O I：

10.1021/cm00006a020

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The solid-state route using Y2O3, BaCO3, and CuO to synthesize the YBa2Cu3O7 superconductor requires an effective and complete decomposition of the carbonate. We have found that by reducing starting particle size, improving the mixing, and vacuum processing most of the BaCO3 decomposes in the 550-600 degrees C range. The enhanced decomposition is lower by >150 degrees C than the expected BaCO3 decomposition temperature under similar conditions. The cause of this enhancement was found to be a reduced form of CuO that reacts with the BaCO3 to form BaCu2O2. Upon oxidation, the 1-2-3 phase forms only from the reacted BaCO3, even at temperatures below 650 degrees C. Virtually complete conversion to the 1-2-3 phase occurs by vacuum processing at similar to 750 degrees C followed by oxidation at similar to 800 degrees C.

引用

页码：665 / 668

页数：4

共 11 条

[1]

Basu T. K., 1976, CHEM PHYS, V80, P1889

[2]

Bunker B. C., 1988, Better Ceramics Through Chemistry III. Symposium, P373

[3] MECHANOCHEMICAL REACTIONS OF SOLIDS WITH GASES [J].