化学压力调节的BaTiO3 薄膜具有很大的自发极化和高基里温度
Yilin Wang1,2, Linxing Zhang1, Jiaou Wang3
1Beijing Advanced Innovation Center for Materials Genome Engineering, Institute of Solid State Chemistry, University of Science and Technology Beijing, Beijing 100083, China.
Journal of the American Chemical Society
|April 26, 2021
概括
研究人员开发了一种新的化学压力方法来增强酸 (BaTiO3) 薄膜,实现创纪录的铁电和基里温度. 这种方法为改善无压材料提供了一个有前途的途径.
科学领域:
- 材料科学
- 固态物理
- 铁电行业
背景情况:
- 酸 (BaTiO3) 是一种众所周知的无材料,但在自发偏振和基里温度方面存在局限性.
- 现有的使用元素注的化学压力方法在增强BaTiO3特性方面取得了有限的成功.
研究的目的:
- 为高性能BaTiO3薄膜开发一种促进化学压力路径.
- 显著提高BaTiO3的铁电特性和基里温度.
主要方法:
- 在立方BaO和四边形BaTiO3之间通过连贯格子应变施加负化学压力 (∼-5.7 GPa).
- 使用应变来诱导高四角性 (c/a = 1.12) 和大 Ti 位移.
- 分析负压对结合状态的影响,包括Ba 5p-O 2p杂交和Ti eg-O 2p结合.
主要成果:
- 在BaTiO3膜中达到100μC/cm2的最高剩余极化 (Pr).
- 获得超过1000°C的高基里温度 (Tc).
- 由于在负化学压力下修改的结合状态,显著增强了极化.
结论:
- 推广的化学压力方法有效地提高了BaTiO3的铁电性和热稳定性.
- 负化学压力通过改变粘合特性来改变材料特性.
- 这种方法具有超越铁电的各种功能材料的改进潜力.
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