在低压下显著增强负热膨胀在Cu2P2O7
Naike Shi1, Longlong Fan2,3, Yuanji Xu4
1Department of Physical Chemistry, University of Science and Technology Beijing, Beijing, 100083, China.
Small (Weinheim an der Bergstrasse, Germany)
|June 26, 2024
概括
施加低压可显著增强铜铁酸盐 (Cu2P2O7) 的负热膨胀 (NTE). 这一改进提高了其在复合材料中的热补偿能力.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 实现受控负热膨胀 (NTE) 是具有挑战性的,很少有方法可以改善内在的NTE.
- 铜酸 (Cu2P2O7) 呈现NTE,但其在复合材料中的热补偿潜力在环境条件下仍然有限.
研究的目的:
- 显著增强Cu2P2O7.7的内在负热膨胀 (NTE).
- 研究Cu2P2O7.7中压力诱导的NTE增强背后的机制.
- 探索复合材料中增强的NTE材料的实际应用.
主要方法:
- 对Cu2P2O7.7的低压应用.
- 高压同步子X射线衍射.
- 可变的温度和压力中子衍射.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 热膨胀的体积系数 (CTE) 在0.25 GPa时达到-50.0 × 10^-6 K^-1 (150-325K),增加了47.5%.
- 施加的压力缩小了相邻的CuO层和柱的距离.
- 在α-Cu2P2O7中,低频声对NTE的贡献得到了增强.
结论:
- 低压是一种有效的方法,可以显著提高Cu2P2O7.7的内在NTE.
- 增强的NTE归因于结构变化和更好的语音贡献.
- 这项工作为开发用于热补偿应用的先进NTE材料提供了途径.
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