通过近球理论合理设计类似陶的分子铁电
Zhen-Hong Wei1, Zhen-Tao Jiang1, Xiu-Xiu Zhang1
1Ordered Matter Science Research Center , Nanchang University , Nanchang 330031 , People's Republic of China.
Journal of the American Chemical Society
|January 9, 2020
概括
研究人员开发了一种新的类似陶的分子铁电, [3.2.1-dabco]BF4,用于柔性电子. 这种材料在室温下在多晶薄膜中表现出极好的铁电性能.
科学领域:
- 材料科学
- 固态物理
- 晶体学
背景情况:
- 分子铁电比传统陶具有灵活性和环保处理等优势.
- 开发用于实际应用的多晶分子铁电仍然是一个挑战.
研究的目的:
- 合成一种类似于陶的分子铁电,具有用于多晶薄膜应用的增强性.
- 探索改善铁电性能的分子设计策略.
主要方法:
- 基于准球理论的1,5-diazabicyclo[3.2.1]octonium tetrafluoroborate ([3.2.1-dabco]BF4) 的合成.
- 修改了阴离子结构 ([2.2.2-dabco]+到[3.2.1-dabco]+) 以减少对称性,同时保持准球形状.
- 聚晶薄膜的相位过渡和铁电性质的表征.
主要成果:
- 在357K时成功合成了m3mFmm2相变的[3.2.1-dabco]BF4.
- 在室温下以多晶薄膜形式实现出色的铁电性能.
- 与[2.2.2-dabco]BF4相比,自发极化 (Ps) 从4.9μC cm-2增加到5.5μC cm-2.
- 通过分子设计将极轴数量提高到六个.
结论:
- 准球体理论为设计类似陶的分子铁电提供了可行的途径.
- 精确的分子设计,特别是改变离子对称性,有效提高铁电性质.
- [3.2.1-dabco]BF4显示了灵活电子设备的巨大潜力.
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