Prepared and magnetic Properties of B4C/C Coated Co Nanocapsules
B4C/C coated Co nanocapsules were prepared by arc-discharging a Co-B amorphous alloy.The structure,morphology and surface composition as well as magnetic properties were investigated by X-Ray diffraction,High Resolution Transmission Electron Microscopy and XPS photoelectron spectrum as well as Vibrating Sample Magnetometer,respectively.The results show the as-prepared nanoparticles form in a core-shell structure with the size of nanopartictes in range of 20-100nm,the thickness of the shell is about 3-10nm.The core is Co grains,while the shell is B4C/C compound.That B4C coated Co nanoparticles form in a core-shell structure ascribed to Co as catalysts accelerating reaction between B with C ionize in the arc-discharge course.This structure can prevent Co nanoparticles from oxidation and agglomeration.A saturation magnetization of Ms=75.6 Am2/kg and a coercive force of Hc=20.1 kA/m are achieved for as-prepared nanocapsules by VSM.For as-prepared nanocapsules,the saturation magnetization is reduced and coercive force of is enhanced while Comparing with Co block.The increase coercive force for as-prepared nanoparticles can be mainly ascribed to size of particles diminished and the domain-wall depinned in the multi-domain particles.
Co(B4C/C) Core-shell structure Magnetic properties Arc-discharge
Da-wei Yu Jin-bing Zhang Gui-mei Shi
Shenyang University of Technology,Shenyang Liaoning 110870,P.R..China
国际会议
大理
英文
328-331
2011-08-18（万方平台首次上网日期，不代表论文的发表时间）