系统和可控制的负,零和正热膨胀在立方Zr{1-x}Sn{-x}Mo2O8
Sarah E Tallentire1, Felicity Child, Ian Fall
1Department of Chemistry, Durham University, Science Laboratories, South Road, Durham DH1 3LE, United Kingdom.
Journal of the American Chemical Society
|July 31, 2013
概括
研究人员开发了具有可调节热膨胀的Zr1-xSnxMo2O8材料. 这种单相系统允许控制收缩和膨胀,与复合材料不同,用于先进的应用.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 传统材料往往表现出有限或固定的热膨胀特性.
- 复合材料通常用于实现可调节的热膨胀,这可能导致接口问题.
- 了解和控制热膨胀对于航空航天,电子和精密工程的应用至关重要.
研究的目的:
- 为了合成和描述一种新的材料家族,Zr1-xSnxMo2O8 (0 < x < 1).
- 为了证明在单相材料中对同位热膨胀系数的系统控制.
- 研究这些材料的结构性质和相变,特别是"立方体"SnMo2O8.8.
主要方法:
- 具有不同组成的Zr1-xSnxMo2O8材料的固态合成.
- 使用X射线衍射 (XRD) 和热膨胀测量进行表征.
- 时间和温度依赖的衍射研究,以探测相位过渡.
主要成果:
- 一系列Zr1-xSnxMo2O8材料成功合成了可调节的同位素热膨胀系数.
- 线性热膨胀系数 (αl) 从 -7.9(2) × 10−6 到 +5.9(2) × 10−6 K−1 (12-500 K) 在单个阶段实现.
- 该研究报告了"立方"SnMo2O8的详细结构和热膨胀行为,包括有序和无序状态之间的相位过渡.
结论:
- Zr1-xSnxMo2O8系统提供了一个独特的单相平台,用于精确控制热膨胀.
- 这些材料为需要可调整扩展的应用提供了复合材料的可行替代品.
- 这些发现有助于对过渡金属氧化物及其热行为中的结构性质关系的基本理解.
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