在 (1 - x) ((K0.5Na0.5) NbO3-x(Ba0.5Sr0.5) TiO3铁电固体溶液中的组合诱导结构相变
Satyaranjan Sahoo1, Dhiren K Pradhan2, Shalini Kumari3
1Department of Physics and Astronomy, National Institute of Technology Rourkela, Rourkela, Odisha, 769008, India.
Scientific reports
|November 5, 2023
概括
这项研究绘制了无 (酸) -酸 (KNN-BST) 固体溶液的相图. 正方形-四角形相界显示了增强的介电性质,这对于电子设备至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 铁电材料 铁电材料
背景情况:
- 具有可切换和自发偏振的铁电材料是新型电子设备的关键.
- 矿结构的固体溶液可以通过允许相位共存来增强物理功能.
- 阶段图对于理解材料属性及其基础物理是必不可少的.
研究的目的:
- 要构建 (K0.5Na0.5NbO3) - ((Ba0.5Sr0.5TiO3) (KNN-BST) 系统的相位图.
- 为了研究组成,相变和物理性质之间的关系.
- 确定电子应用程序功能增强的区域.
主要方法:
- 使用传统的固态反应合成 (1-x) KNN-xBST固溶液陶 (0 ≤ x ≤ 0.3).
- 通过X射线衍射和拉曼光谱来确定结构相位过渡.
- 介电,铁电和压电测量以表征物理性质.
主要成果:
- 观察到构成依赖的结构相过渡:正角形 → 正角形 + 四角形 → 四角形 + 立方形 → 立方形.
- 在正方体+四边形双相区域 (0.025 ≤ x ≤ 0.15) 在室温下表现出增强的介电常数.
- 阶段过渡温度 (T O-T 和 T C) 随着BST度的增加而下降.
- 铁电特性 (2Pr和Ec) 随着BST度的增加而下降,x=0.025显示最大压电系数.
结论:
- 成功建立了KNN-BST系统的相位图.
- 正方形-四角形相共存区域对于增强的介电性能至关重要.
- 展示了相位转换和性质的组合调整,为设计无铁电材料提供了途径.
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