甲基调节触发了高温铁弹性相位过渡的过程
Si-Yue Zhang1, Zhi-Cheng Zhang1, Tie Zhang1
1Ordered Matter Science Research Center, Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing 211189, People's Republic of China. dawei@seu.edu.cn.
Dalton transactions (Cambridge, England : 2003)
|July 12, 2023
概括
研究人员为介电开关开发了新的有机-无机混合材料. 延长了阴阳的时间.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 有机-无机混合材料 (OIHM) 是多功能介电开关的关键.
- 具有介电相变的分子铁弹性材料提供可调节的光学和电气性能.
- 设计具有高过渡温度 (Tc) 的铁弹性材料是一个重大的挑战.
研究的目的:
- 根据[TTMA]2CdI4.4进行一系列OIHM的合成和表征.
- 为了研究阴离子修饰对相变温度 (Tc) 和铁弹性的影响.
- 开发具有增强性能的新型铁弹性材料.
主要方法:
- 具有不同阴离子结构的OIHM的合成: [TTMA]2CdI4 (1), [TMEA]2CdI4 (2), [TMPA]2CdI4 (3) 和 [TMIPA]2CdI4 (4).
- 差分扫描热量计 (DSC) 检测相位过渡.
- 温度依赖的介电常数测量.
- 结构分析,以了解阶段过渡的机制.
主要成果:
- 一系列OIHM通过延长子中的链来成功合成.
- 化合物1,2和3表现出介电相变,由DSC和介电试验证实.
- 铁弹性化合物3显示Tc显著增加,为387K.
- 结构分析显示,有序-无序离子运动驱动相位过渡.
结论:
- 在阳离子中延长链有效地增加了OIHM中的相变温度 (Tc).
- 化合物3在室温下表现出铁弹性,这是由于其Tc的升高.
- 这些发现为设计用于先进应用的高性能铁弹性材料提供了一条道路.
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