Synthesis and characterization of core-shell structured bimagnetic cobalt-coated iron nanoparticles

摘要：

Core-shell structured nanoparticles with ferromagnetic core (Fe) and shell (Co) were prepared by a chemical reduction method. By adjusting the deposition parameters, the core-shell particles with various Fe: Co molar ratios were obtained. The saturation magnetization decreased with the increase of Cobalt content. The properties of core-shell nanoparticles synthesized under a magnetic field were compared with those prepared without a magnetic field. For the nanoparticles prepared without magnetic filed, the coercivity (Hc) increased with increasing Co content due to the large anisotropy of Co, whereas for the nanoparticles prepared under a magnetic field, the Hc was much lower. The ZFC/FC curves suggested that these particles were ferromagnetic at room temperature. The anisotropy constant K at 340K for core-shell nanoparticle is estimated to be 0.83×105 erg/cm3. The second ferromagnetic phase transition may occur at the temperature lower than 25 K, which led to a drastic change of magnetization at low temperatures.

关键词： core-shell structure nanoparticles bi-magnetic magnetic properties

作者: K.P. Su Z.W. Liu X.X. Shan Z.G. Zheng X.C. Zhong H.Y. Yu D.C. Zeng

作者单位: School of Materials Science and Engineering, South China University of Technology, Guangzhou,China, School of Materials Science and Engineering, South China University of Technology, Guangzhou, China,

会议类型: 国际会议

会议名称: 11th IUMRS International Conference in Asia(第十一届国际材联亚洲材料大会 IUMRS-ICA 2010)

会议地点: 青岛

会议语种:英文

页码: 370-375

在线出版日期: 2010-09-25（万方平台首次上网日期，不代表论文的发表时间）