强极矿的巨大体积收缩
Zhao Pan1,2,3, Jun Chen1,3, Xingxing Jiang4
1Department of Physical Chemistry, University of Science and Technology Beijing , Beijing 100083, China.
Journal of the American Chemical Society
|October 11, 2017
概括
研究人员通过替代增强了酸材料的负热膨胀 (NTE). 这项研究实现了巨大的体积收缩,为开发先进的NTE材料提供了新的途径.
科学领域:
- 材料科学
- 固态物理
- 晶体学
背景情况:
- 负热膨胀 (NTE) 是一种具有重大科学和实践意义的独特物理性质.
- 在现有材料中增强NTE具有挑战性,因为化学修饰往往会削弱这种特性.
- 开发具有改进的NTE材料对于先进的技术应用至关重要.
研究的目的:
- 在酸 (PbTiO3) 基材料中实现增强的负热膨胀 (NTE).
- 研究替代对PbTiO3的铁电和热膨胀特性的影响.
- 探索设计具有显著 NTE 的材料的新方法.
主要方法:
- 在酸 (PbTiO3) 格子中化学替代 (V),形成Pb(Ti1-xVx) O3.
- 分析格子结构,极化和结合的变化.
- 在广泛的温度范围内对热膨胀特性进行实验性描述.
主要成果:
- 替代瓦纳显著促进了Pb{Ti1-xVx) O3中的晶格四角性,与增强的自发偏振和共价键有关.
- Pb(Ti0.9V0.1) O3显示出明显强大的非线性NTE,其体积热膨胀系数αV = -3.76 × 10^-5 /°C (25-550 °C).
- 在铁电到电相位过渡期间观察到Pb{0.7V0.3) O3的内在巨型体积收缩,这归因于自发体积铁电收缩.
结论:
- 通过利用铁电性质,该研究成功地提高了Pb{Ti1-xVx) O3的NTE.
- 这些发现表明通过调整铁电特性来探索新的NTE材料的有效策略.
- 这项工作扩大了NTE材料的范围,并为开发具有大,可控制体积变化的材料提供了途径.
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