期刊
JOURNAL OF PHYSICAL CHEMISTRY C
卷 117, 期 21, 页码 11436-11443出版社
AMER CHEMICAL SOC
DOI: 10.1021/jp402823h
关键词
-
资金
- Agence Nationale de la Recherche (ANR) [ANR08-BLAN-NT09-459731]
Core-shell nanoparticles (NPs), which consist in a ferrimagnetic (FIM)/antiferromagnetic (AFM) interface and result in exchange bias coupling, became recently of primary importance in the field of magnetic nanoparticles. The enhancement of some applications such as hyperthermia or magnetic storage media based on the miniaturization of devices is correlated to the size reduction of NPs, which results in the decrease of the magnetocrystalline anisotropy and of the blocking temperature. We present here the synthesis of Fe3-delta O4@CoO core-shell NPs by a one-pot seed-mediated growth process based on the thermal decomposition of metal complexes at high temperature. A 2 nm thick CoO shell was grown homogeneously from the starting Fe3-delta O4 core surface. The Fe3-delta O4@CoO core-shell NP structure has been deeply investigated by performing XRD and advanced techniques based on TEM such as EELS and EFTEM. The high quality of the core-shell interface resulted in the large exchange bias coupling at 5 K (H-E approximate to 4.1 kOe) between the FIM and the AFM components. In comparison to starting Fe3-delta O4 NPs, the dramatic enhancement of the magnetic properties such as a high coercive field (at 5 K, H-C approximate to 15 kOe) were measured. Furthermore, the core-shell structure resulted in the enhancement of the magnetocrystalline anisotropy and the increase of the blocking temperature to 293 K.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据