HoB2和Nb替代的HoB2的磁热特性和微结构
Mahboobeh Shahbazi1,2, Ali Dehghan Manshadi3, Kiran Shinde4
1Centre for Materials Science and School of Chemistry and Physics, Queensland University of Technology, Brisbane, QLD 4001, Australia.
Materials (Basel, Switzerland)
|February 26, 2025
概括
在 Holmium diboride (HoB2) 中的替代增强了其磁性特性,导致更高的基里温度 (TC) 和显著的磁热效应,这对于磁性制冷应用至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 霍尔二化物 (HoB2) 是一种具有潜在磁热性质的材料.
- 了解兴奋剂对其磁性和微观结构特征的影响对于优化其性能至关重要.
研究的目的:
- 为了合成和表征 (Nb) 替代的HoB2.
- 研究Nb替代对HoB2.2的磁热性质和微观结构的影响.
主要方法:
- 多晶 HoB2 和 Nb 替代 HoB2 块的弧融合成.
- 用X射线衍射 (XRD) 进行结构分析和单元细胞参数的确定.
- 微观结构分析观察谷物形态和大小.
- 磁热性能测量,包括磁变化 (ΔSM) 和相对冷却功率 (RCP).
主要成果:
- 通过Ho0.93Nb0.07B2.2.的立体测量证实了Nb的替代.
- 替代Nb导致了较小的颗粒大小 (~微米以下) 和增加的基里温度 (TC).
- 在10 T时观察到46.8 Jkg-1K-1 (HoB2) 和38.2 Jkg-1K-1 (Ho0.93Nb0.07B2) 的最大磁变化 (ΔSM).
- 尽管存在小相,但计算了高相对冷却功率 (RCP).
结论:
- 替代有效地改变了微观结构,并增强了holmium diboride的磁热性质.
- 观察到的磁热性行为与其他霍尔玻化物化合物一致.
- 替代Nb的HoB2显示出对磁性制冷应用的前景.
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