在Tl-Pb-Sr-Ca-Cu-O系统中,散装超导率高达122K
Science (New York, N.Y.)
|October 14, 1988
概括
已经合成了新的氧化铜超导体,不包括. 这些新型材料表现出高临界温度 (T ((c)) 到120K,为先进的超导应用提供了潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 无机化学 无机化学 有机化学
背景情况:
- 高温超导体的开发对能源和技术至关重要.
- 氧化物超导体,特别是那些涉及铜的超导体,已经显示出显著的前景.
- 以前的研究集中在含的酸盐上,因此需要探索替代成分.
研究的目的:
- 为了合成和描述新型的高温超导体.
- 为了研究不含的铜氧化物.
- 确定这些新材料的超导性能,特别是临界温度 (T) (c).
主要方法:
- 使用固态合成技术来制备氧化物材料.
- 用X射线衍射 (XRD) 进行结构分析和相位识别.
- 进行电阻测量以确定超导过渡温度 (T) (c).
主要成果:
- 基于和铜氧化物,没有的新型超导材料已成功制备.
- 化合物 (Tl{0.5) Pb{0.5)) Sr{2) CaCu{2) O{7) 的T{c) 值约为85K.
- 化合物 (Tl(0.5) Pb(0.5)) Sr(2) Ca(2) Cu(3) O(9) 显示了一个T(c) 约为120K.
- 这两种材料结晶成四角形结构,其特定的格子参数由XRD决定.
- 单晶X射线衍射数据允许对较高T (c) 阶段进行详细的结构细化.
结论:
- 成功合成没有的氧化铜超导体扩大了已知高T (c) 材料的家族.
- 这些新型化合物达到高达120K的T (c) 值,凸显了它们在实际应用中的潜力.
- 结构性特征提供了对这些系统中组成,结构和超导性之间的关系的基本见解.
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