一个含有半基的2D微孔磁铁,具有由溶剂诱导的从Tc=26到80K的切换
Ie-Rang Jeon1, Bogdan Negru1, Richard P Van Duyne1
1Department of Chemistry, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.
Journal of the American Chemical Society
|November 18, 2015
概括
研究人员使用四氧化醇基联体制造了一种新的微孔磁体. 这种新材料具有自发磁化和高表面积,为先进的磁性应用铺平了道路.
科学领域:
- 材料科学
- 无机化学
- 磁力学
背景情况:
- 四氧化配体是具有构建功能材料的潜在氧化还原活性分子.
- 开发多孔磁性固体对于催化,气体储存和传感中的应用至关重要.
研究的目的:
- 将四氧化基桥接连体纳入微孔磁性固体.
- 描述产生的材料的结构,电子特性和磁性行为.
主要方法:
- 2,5-二-3,6-二-1,4-基 (LH2) 与Fe (II) 的金属化
- 射线衍射,拉曼光谱和莫斯尔光谱用于结构和电子分析.
- 用于测定表面积的N2吸附和测量磁性特性的电磁感应.
主要成果:
- 由于自发电子转移而形成具有Fe (III) 中心和混合价值连接体的固体.
- 获得了BET表面积为885m2/g的脱阶段.
- 观察到自发磁化低于80K (溶解) 和26K (激活),磁性歇斯底里分别高达60K和20K.
结论:
- 反氧活性四氧化连体可以支持微孔磁体的形成.
- 这项工作介绍了第一个结构特征的含有四氧化醇基连接体的扩展固体.
- 开发的材料对需要多孔磁性固体的应用具有前景.
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