强大的杂交驱动PbTiO3基铁电在PbTiO3基铁电中的异常增强负热膨胀
Zhao Pan1,2, Sergey A Nikolaev2, Xi Shen1
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China. zhaopan@iphy.ac.cn.
Materials horizons
|February 26, 2026
概括
酸基铁电材料中的更强的共价键解释了它们的负热膨胀 (NTE). 这项研究阐明了NTE的微观起源,使得能够设计用于热膨胀控制的先进材料.
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:
- 负热膨胀 (NTE) 材料对于基础研究和工程应用,需要热膨胀控制至关重要.
- 之前的工作通过增加四角扭曲来增强PbTiO3-BiFeO3和PbTiO3-BiCoO3铁电中的NTE,但显微机制尚不清楚.
研究的目的:
- 研究基于PbTiO3的铁电材料中增强负热膨胀 (NTE) 背后的微观机制.
- 探索温度依赖的化学键特性和电子密度分布.
主要方法:
- 高能同步射线X射线粉碎衍射与瑞特维尔德精细化.
- 最大的方法分析.
- 第一个原则计算.
主要成果:
- 在A位点 (Pb/Bi-O2) 和B位点 (Ti/Fe/Co-O1) 债券中观察到强烈的共价的直接证据.
- 协价性质与通过阴离子位移的自发偏振有关.
- 不同的Fe-O和Co-O键共价性导致了对比的体积行为:PbTiO3-BiFeO3中的非线性NTE和PbTiO3-BiCoO3.3中的巨大收缩.
结论:
- 该研究阐明了基于PbTiO3的铁电材料中NTE的微观起源,将其归因于强共价键.
- 研究结果为设计新型材料提供了洞察力,这些材料具有针对热管理应用的定制NTE特性.
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