Magnetic Properties and Morphology of the Cobalt Particles Prepared in Different Liquid Solvent
The two kinds of flower-like ultrafine cobalt particles were prepared by reducing cobalt chloride(CoCl2·6H2O) with hydrazine hydrate(N2H4·H2O) under ultrasonic and microwave radiation,in which ethanol-water or ethylene glycol-water mixture was used as solvent.The morphology,crystal structure and magnetic properties of the as-prepared particles were characterized by scanning electron microscope (SEM),x-ray diffraction pattern (XRD) and vibrating sample magnetometer (VSM).The results show that the petals of the flower-like cobalt particles prepared in the ethanol-water system were dendritic,while the petals of the flower-like cobalt particles prepared in the ethylene glycol-water system were sword-like.The crystal structure of cobalt particles prepared in the two kinds of systems both consisted of hexagonal close-packed cubic phase and face-centered cubic phase,but the relative content was different.The saturation magnetization of the cobalt particles with dendritic petals and the cobalt particles with sword-like petals was the same approximately,but their coercivity was greatly different (the difference in value about 7184.14A?m-1),which might be attributed to the magnetocrystalline anisotropy and shape anisotropy.
Cobalt particles Hydrazine reduction Coercivity
Xuemin Huang Quansheng Wang Ying Liu Xiuchen Zhao Shulai Wen
School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
国际会议
the Chinese Materials Congress 2012(2012年中国材料大会(CMC2012))
太原
英文
192-197
2012-07-13(万方平台首次上网日期,不代表论文的发表时间)