C2O42--模板[Ln2Ni]异金属化合物用于在低电场下增强磁热效应
Qin Wang1, Lingxi Xu2, Jilei Wang1
1State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211816, P. R. China. yanxu@njtech.edu.cn.
Dalton transactions (Cambridge, England : 2003)
|January 13, 2025
概括
兰化物过渡异金属化合物显示出作为磁性制冷剂的前景. 新的Gd2Ni化合物表现出极好的磁热效应,在低温和低电场下表现优于以前的材料.
科学领域:
- 磁电化学 磁电化学 磁电化学
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
背景情况:
- 在磁性制冷剂应用中探索了兰化物过渡 (3d-4f) 异金属化合物.
- 氧酸盐离子 (C2O4^2-) 作为设计新型磁性材料的有效模板.
研究的目的:
- 设计和合成用于磁性制冷的新型化物过渡异金属化合物.
- 研究这些新型化合物的结构和磁性特性.
主要方法:
- 使用兰他化物 (Gd, Sm, Tb) 和合成异金属化合物,用氧酸盐和乙烯基二胺酸为模板.
- 用X射线衍射进行结构分析,揭示2D层和3D金属有机框架.
- 磁化测量以评估磁性特性和磁热效应.
主要成果:
- 一系列的{[Ln2Ni(L) ((C2O4) 2 ((H2O) 2) ·H2O}化合物被成功合成.
- 结构分析证实了一个独特的3D金属有机框架结构,由氧酸盐离子模板.
- 在2.0K和7.0T时,Gd2Ni的最大变化 (-ΔSmaxm) 为38.0J kg^-1 K^-1.
- 在低电场时,Gd2Ni表现出显著的磁热效应,在2.0 T时 - ΔSm = 25.1 J kg^-1 K^-1 和在1.0 T时 (14.5 J kg^-1 K^-1).
结论:
- 合成的Gd2Ni化合物显示出作为磁性制冷剂的绝佳潜力,特别是在低温下.
- 在Gd2Ni中观察到的磁热效应超过了之前报告的许多3d-4f异金属化合物的磁热效应.
- 三维金属有机框架结构在观察到的磁性特性中起着至关重要的作用.
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