Wei Guodong, Wei Lin, Wang Dong, Chen Yanxue, Tian Yufeng, Yan Shishen, Mei Liangmo, Jiao Jun
School of Physics and State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250100, P. R. China.
School of Microelectronics, Shandong University, Jinan, 250100, P. R. China.
Sci Rep. 2017 Oct 2;7(1):12554. doi: 10.1038/s41598-017-12948-6.
Lithium-ion (Li-ion) batteries based on spinel transition-metal oxide electrodes have exhibited excellent electrochemical performance. The reversible intercalation/deintercalation of Li-ions in spinel materials enables not only energy storage but also nondestructive control of the electrodes' physical properties. This feature will benefit the fabrication of novel Li-ion controlled electronic devices. In this work, reversible control of ferromagnetism was realized by the guided motion of Li-ions in MnFeO and γ-FeO utilizing miniature lithium-battery devices. The in-situ characterization of magnetization during the Li-ion intercalation/deintercalation process was conducted, and a reversible variation of saturation magnetization over 10% was observed in both these materials. The experimental conditions and material parameters for the control of the ferromagnetism are investigated, and the mechanism related to the magnetic ions' migration and the exchange coupling evolution during this process was proposed. The different valence states of tetrahedral metal ions were suggested to be responsible for the different performance of these two spinel materials.
基于尖晶石过渡金属氧化物电极的锂离子（Li-ion）电池展现出了优异的电化学性能。Li离子在尖晶石材料中的可逆嵌入/脱嵌不仅能够实现能量存储，还能对电极的物理性质进行无损控制。这一特性将有利于新型锂离子可控电子器件的制造。在这项工作中，利用微型锂电池装置，通过Li离子在MnFeO和γ-FeO中的定向移动实现了铁磁性的可逆控制。对Li离子嵌入/脱嵌过程中的磁化强度进行了原位表征，在这两种材料中均观察到饱和磁化强度有超过10%的可逆变化。研究了控制铁磁性的实验条件和材料参数，并提出了在此过程中与磁性离子迁移和交换耦合演化相关的机制。四面体金属离子的不同价态被认为是这两种尖晶石材料表现出不同性能的原因。
