微/纳米晶体的压力诱导结构相变和光发光特性 HoF3
Tingting Yan1,2, Dandan Zhang2, Dongyang Xi1
1School of Science, Shenyang Jianzhu University, Shenyang 110168, China.
Inorganic chemistry
|October 15, 2024
概括
合成化荷 (HoF3) 纳米晶体揭示了压力诱导的相变. 这些转变改变了晶体结构和光发光,为稀土三化物应用提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 控制晶体大小和形态对于调整材料特性至关重要.
- 稀土三化物 (REF3) 在压力下表现出多样化的结构和光学行为.
- 了解HoF3中压力诱导的相变是其潜在应用的关键.
研究的目的:
- 为了合成具有受控大小和形态的HoF3晶体.
- 为了研究HoF3微/纳米晶体的压力诱导的相变和光发光 (PL) 特性.
- 阐明阶段过渡期间的结构变化和协调数量变化.
主要方法:
- 通过控制含水量合成HoF3晶体,产生微和纳米晶体.
- 在现场高压光发光 (PL) 光谱学研究相位过渡.
- 第一原则计算以确定结构转型和协调变化.
- 高压拉曼光谱,以确认转换期间的格子模式行为.
主要成果:
- HoF3晶体从微晶体转变为~100nm纳米晶体,含水量减少.
- 在5GPa (12GPa对于纳米晶体) 和12GPa时观察到两个结构相变.
- 纳米粒子表现出增强的光强度,这种强度随着压力而变化.
- 第一个原则的计算预测了从正方形结构向六角结构的过渡,holmium协调数 (9到11) 的增加.
结论:
- 该研究精确地绘制了压力下的HoF3的结构变化.
- 观测到的相变提供了对稀土三化物结构的更深入的了解.
- 这些发现对稀土材料的开发和应用具有重要意义.
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