通过结构演变改善磁热效应在加多酸盐化物中Ba2Gd(BO3) 2X (X = F, Cl)
Yuwei Chen1,2, Pifu Gong1,2, Ruixin Guo1,2
1Center for Crystal Research and Development, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
Inorganic chemistry
|September 14, 2023
概括
一种新的加多酸,Ba2Gd(BO3)2F,已合成,并表现出优越的磁热效应. 这种材料对先进的磁性制冷应用具有前途.
科学领域:
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 加多化合物以其磁热性质而闻名.
- 酸化物具有独特的结构和磁性特性.
- 了解结构属性关系对于开发新的磁性材料至关重要.
研究的目的:
- 为了合成和描述一种含有酸的新型Gd3+,Ba2Gd(BO3) 2F.
- 研究新化合物的结构,热,光学和磁性特性.
- 将其磁热性能与相关材料进行比较.
主要方法:
- 使用BaF2-NaF-B2O3流体进行晶体生长的高温溶液方法.
- 用X射线衍射来确定晶体结构 (正方体,空间组Pnma).
- 磁性测量以评估磁热效应.
- 热分析 (TGA/DSC),红外 (IR) 光谱和UV-Vis-NIR扩散反射频谱用于表征.
- 电子结构分析的第一原则计算.
主要成果:
- 成功合成了Ba2Gd(BO3) 2F.的单晶.
- 确定其晶体结构,与Ba2Gd不同) 2Cl.
- 观察到一个显著的磁热效应 (-ΔSm,max = 27.82 J·kg-1·K-1在2K和9T),超过了Ba2Gd(BO3) 2Cl.
- 热稳定性,光学性能和电子带结构的表征.
结论:
- Ba2Gd(BO3)2F是一种具有独特结构的新型材料.
- 该化合物表现出有希望的大磁热效应,使其成为磁冷却的潜在候选者.
- 该研究提供了关于其物理性质和电子结构的全面数据.
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