通过锌取代提高磁铁矿纳米颗粒的低场磁电阻。

Enhancing low-field magnetoresistance in magnetite nanoparticles via zinc substitution.

机构信息

State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, P. R. China.

出版信息

Phys Chem Chem Phys. 2018 Jun 27;20(25):17245-17252. doi: 10.1039/c8cp00843d.

DOI:10.1039/c8cp00843d

PMID:29901060

Abstract

We report a strategy to enhance the room temperature low-field magnetoresistance (LFMR) behavior of Fe3O4 nanoparticle (NP) assemblies by controlled Zn-substitution. The Zn-substituted 7 nm ZnxFe3-xO4, (x = 0 to 0.4) NPs are prepared by thermal decomposition of metal acetylacetonates (M(acac)n, M = Fe2+, Fe3+, and Zn2+). The substitution increases NP magnetic susceptibility (χ) and makes the magnetic moment more sensitive to low magnetic fields. As a result, the Zn0.3Fe2.7O4 NP assembly with NPs separated by tridecanoate exhibits a large magnetoresistance (MR) ratio of -14.8% at 300 K under a 4.5 kOe magnetic field. The demonstrated approach to control NP substitution to enhance low-field magnetoresistance of the NP assemblies provides an attractive new strategy to fabricate Fe3O4-based magnetic NP assemblies with desirable transport properties for sensitive spintronic applications.

摘要

我们报告了一种通过控制 Zn 取代来提高 Fe3O4 纳米颗粒（NP）组装体室温低场磁阻（LFMR）性能的策略。通过金属乙酰丙酮盐（M(acac)n，M = Fe2+、Fe3+和 Zn2+）的热分解制备 Zn 取代的 7nm ZnxFe3-xO4，（x = 0 至 0.4） NPs。取代增加了 NP 磁化率（χ），使磁矩对低磁场更敏感。结果，在 4.5kOe 磁场下，由 tridecanoate 隔开的 NPs 的 Zn0.3Fe2.7O4 NP 组装体在 300K 下表现出 -14.8%的大磁阻（MR）比。该方法控制 NP 取代以提高 NP 组装体的低场磁阻，为制备具有理想输运性能的基于 Fe3O4 的磁性 NP 组装体提供了一种有吸引力的新策略，可用于灵敏的自旋电子应用。