Yttrium barium copper oxide
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| Yttrium barium copper oxide | |
|---|---|
| Image:BaYCusuperconduct.jpg | |
| General | |
| Systematic name | Yttrium barium copper oxide |
| Other names | YBCO, Y123, yttrium barium cuprate |
| Molecular formula | YBa2Cu3O7−x |
| Molar mass | Variable. |
| Appearance | Black solid. |
| CAS number | [107539-20-8] |
| Properties | |
| Density and phase | ? g/cm3, solid |
| Solubility in water | Insoluble |
| Melting point | ?°C (? K) |
| Structure | |
| Coordination geometry | Cubic. |
| Crystal structure | Based on the Perovskite structure. |
| Hazards | |
| EU classification | Irritant (I). |
| NFPA 704 | |
| Supplementary data page | |
| Structure and properties | n, εr, etc. |
| Thermodynamic data | Phase behaviour Solid, liquid, gas |
| Spectral data | UV, IR, NMR, MS |
| Related compounds | |
| Related high-Tc superconductors | ? |
| Related compounds | Yttrium(III) oxide Barium oxide Copper(II) oxide |
| Except where noted otherwise, data are given for materials in their standard state (at 25°C, 100 kPa) Infobox disclaimer and references | |
Yttrium barium copper oxide, or YBCO, chemical formula YBa2Cu3O7-δ, is a so-called high-temperature superconductor. It is used for tapes and microwaves filters.
Contents |
History
YBCO's discovery by researchers at the University of Alabama in Huntsville in 1987 launched the era of high-temperature superconductors. YBCO was the first superconductor to break the liquid nitrogen barrier, i.e., the first to be superconducting at a temperature high enough to permit the use of liquid nitrogen as a coolant.
Chemistry
This material remains superconducting until the relatively high temperature of around 94K, the critical temperature, or Tc. Tc varies with oxygen content, that is the value of δ in the formula YBa2Cu3O7-δ.
Structure
See X.S. Wu, F.Z. Wang, S. Nie, J.S. Liu, L. Yang and S.S. Jiang,Physica C, 2000, 339, 129-136 for details.
Image:YinBaCuYsuperconductor.jpg
Image:Cu2inbacuYsuperconduct.jpg
Image:BainbaCyYsuperconductor.jpg
Uses
Because liquid nitrogen, with a boiling point of 77K, is significantly less expensive than liquid helium, YBCO enabled a number of commercial applications. See [1] for a more Detailed study
Yttrium barium copper oxide is used commercially in the fabrication of superconducting tapes and microwave filters.