Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-03T00:50:16.537Z Has data issue: false hasContentIssue false

Synthesis of carbon-encapsulated magnetic nanoparticles by a grain-boundary-reaction

Published online by Cambridge University Press:  15 February 2011

Qixiang Wang
Affiliation:
Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Guoqing Ning
Affiliation:
Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Fei Wei
Affiliation:
Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Guohua Luo
Affiliation:
Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Get access

Abstract

Carbon-encapsulated ferric magnetic nanoparticles were prepared by the grain-boundary-reaction of ultrafine goethite particles. The mechanism of the grain-boundary-reaction was studied with high-resolution transmission electronic microscope, X-ray diffraction and thermo gravimetric analysis. The magnetic properties are measured with a vibrating sample magnetometer. The diameter of carbon-encapsulated ferric magnetic nanoparticles is 30~60 nm, and the coercive force and saturate magnetization are 315 Oe and 30 emu /(g powder), respectively. These composite particles are very stable in air.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Florian, H. L., Science, 291, 2330(2001).Google Scholar
2. Novakova, A. A., Kiseleva, T. Y., Agladze, O. V., Perov, N. S., and Tarasov, B. P., International Journal of Hydrogen Energy, 26, 503(2001).Google Scholar
3. Pardavi, H. M., J. Magn. Magn. Mater., 215-216, 171183(2000).Google Scholar
4. Tagawa, K., Sudoh, K., Takahashi, S., Matsunaga, M., and Ohshima, K., IEEE Trans. Magn. MAG 21, 1492(1985).Google Scholar
5. Gleiter, H., Acta Materialia, 48, 1 (2000).Google Scholar
6. Wang, Q. X., Pan, H. B., Song, B. Z., and Li, H. Z., J. Inorg.Mater., 17, 873(2002).Google Scholar
7. Vallath, D., and Szabo, D. V., J. Nanoparticle Research, 1 235(1999).Google Scholar
8. Wang, Q. X., Song, B. Z., and Li, H. Z., J. Inorg.Mater., 16, 861(2001).Google Scholar
9. Marangoni, R., Serp, P., Feurer, R., Kihn, Y., Kalck, P., and Vahlas, C., Carbon, 39, 443(2001).Google Scholar
10. Massalski, T. B., Binary alloy phase diagrams, 2nd ed. (Ohio: ASM International, 1990) pp 843846.Google Scholar