全无机矿的铁电性证据 量子点
Xia Li1, Shaoqing Chen2, Peng-Fei Liu3,4
1State Key Lab of Inorganic Synthesis and Preparative Chemistry , Jilin University , Changchun 130012 , Jilin , China.
Journal of the American Chemical Society
|February 1, 2020
概括
研究人员在化 (CsPbBr3) 量子点中发现了铁电. 这一突破与相位过渡有关,为使用这些无机矿量子点的新型光电子和能源应用铺平了道路.
科学领域:
- 材料科学
- 固态物理
- 量子光学
背景情况:
- 化矿由于其结合的铁电光学特性,对光电子和能源应用具有前景.
- 在全无机化量子点中对铁电的研究是有限的.
研究的目的:
- 研究和报告CsPbBr3量子点中的铁电.
- 阐明这些材料中铁电-电交换的机制.
主要方法:
- 不同扫描热量计
- 射线衍射
- 传输电子显微镜
- 可变温度的辐射光谱
主要成果:
- 在CsPbBr3量子点中表现出极好的铁电性,和极化为0.25μC/cm2.
- 确定了立方到正方形相位过渡 (Pm3̅m到Pna21) 作为铁电-电切换的机制.
- 由于从328K到78K的相变,观察到绿色发光与红色偏移.
结论:
- 在CsPbBr3量子点中的铁电源源自八面体[PbBr6]4−扭曲和偏离中心的Cs+离子.
- 这一发现为利用无机化矿的铁电光学特性开发多功能材料提供了新的可能性.
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