Characterization and magnetic properties of carbon-coated cobalt nanocapsules synthesized by the chemical vapor-condensation process

IMR OpenIR

	Characterization and magnetic properties of carbon-coated cobalt nanocapsules synthesized by the chemical vapor-condensation process
	Z. H. Wang; C. J. Choi; B. K. Kim; J. C. Kim; Z. D. Zhang
	2003
发表期刊	Carbon
ISSN	0008-6223
卷号	41 期号:9 页码:1751-1758
摘要	Carbon-coated cobalt nanocapsules were synthesized by the chemical vapor-condensation process with cobalt carbonyl (Co-2(CO)(8)) used as precursor and carbon monoxide (CO) as carrier gas. The characterization and magnetic properties of carbon-coated cobalt nanocapsules were investigated systematically. The transmission electron microscope (TEM) images showed that the as-prepared nanoparticles consist of a metal core and an amorphous carbon shell. X-ray diffraction and TEM selected area diffraction revealed the presence of f.c.c. Co phase, h.c.p. Co phase, and minority Co2C, Co3C phases. The saturation magnetization at room temperature of the nanocapsules is 146.9 Am-2 kg(-1), which is 90% of the bulk ferromagnetic element counterpart. The coercive force at room temperature of the nanocapsules is 0.12 T, while the ratio of remnant to saturation magnetization Mr/M-s is about 0.4. The saturation magnetization and the coercive force increase with increasing the decomposition temperature, mainly due to the increase of the size of the magnetic particles. The decomposition of the cobalt carbonyl (Co-2(CO)(8)) and CO gas can decrease efficiently the oxygen content in nanocapsules. The metallic Co nanoparticles completely coated by carbon can resist the dilute acid erosion as well as the oxidation. The thermal stability of the Co nanocapsules is also studied. (C) 2003 Elsevier Science Ltd. All rights reserved.
部门归属	chinese acad sci, met res inst, shenyang natl lab mat sci, shenyang 110016, peoples r china. chinese acad sci, int ctr mat phys, shenyang 110016, peoples r china. korea inst machinery & mat, chang won 641010, kyungnam, south korea.;zhang, zd (reprint author), chinese acad sci, met res inst, shenyang natl lab mat sci, wenhua rd 72, shenyang 110016, peoples r china
关键词	Carbon Composites Crystal Structure Chemical Vapor Deposition Magnetic Properties Transmission Electron Microscopy Fe-co(c) Nanocapsules Arc-discharge Co Particles Nanoparticles Fe Methane Ni Nickel
URL	查看原文
WOS记录号	WOS:000183818100007
引用统计	被引频次：158[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/36071
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	Z. H. Wang,C. J. Choi,B. K. Kim,et al. Characterization and magnetic properties of carbon-coated cobalt nanocapsules synthesized by the chemical vapor-condensation process[J]. Carbon,2003,41(9):1751-1758.
APA	Z. H. Wang,C. J. Choi,B. K. Kim,J. C. Kim,&Z. D. Zhang.(2003).Characterization and magnetic properties of carbon-coated cobalt nanocapsules synthesized by the chemical vapor-condensation process.Carbon,41(9),1751-1758.
MLA	Z. H. Wang,et al."Characterization and magnetic properties of carbon-coated cobalt nanocapsules synthesized by the chemical vapor-condensation process".Carbon 41.9(2003):1751-1758.