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Enhanced Magnetic Transition of Core-Shell Cobalt-Platinum Nanoalloys

Published online by Cambridge University Press:  01 February 2011

Jong-Il Park ,
aNam-Jung Kang ,
Sang-Min Lee ,
Sehun Kim ,
S. J. Oh ,
H. C. Ri  and
Jinwoo Cheon
Jong-Il Park
Affiliation:
Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of science and Technology (KAIST), Taejon, 305-701, Korea.
aNam-Jung Kang
Affiliation:
Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of science and Technology (KAIST), Taejon, 305-701, Korea.
Sang-Min Lee
Affiliation:
Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of science and Technology (KAIST), Taejon, 305-701, Korea.
Sehun Kim
Affiliation:
Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of science and Technology (KAIST), Taejon, 305-701, Korea.
S. J. Oh
Affiliation:
Korea Basic Science Institute (KBSI) Taejon, 305-333, Korea.
H. C. Ri
Affiliation:
Korea Basic Science Institute (KBSI) Taejon, 305-333, Korea.
Jinwoo Cheon
Affiliation:
Department of Chemistry, Yonsei University, Seoul, 120-749, Korea.
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Abstract

Synthesis of ‘solid solution’ and ‘core-shell’ types of well defined Co-Pt based nanoalloys smaller than 10nm have been achieved by redox transmetalation reactions. This redox transmetalation are selectively observed only if the redox potential between two metals is favorable. The composition of the magnetic alloys can also be tuned by adjusting the ratio of reactants. Annealed core-shell nanoparticles transformed into mixed nanoalloys with face centered tetragonal (fct) structures, which show large coercivity and ferromagnetism at room temperature. These nanoparticles can potentially be used as an independent single magnetic bit of tera-bit information storage. Also, this kind of redox transmetalation reaction can be utilized as a general process to synthesize various types of nanoalloys with controlled composition in a selective fashion.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 721: Symposia E/J – Texture and Microstructure in Electronic and Magnetic Films – Nanostructural Magnetic Materials for Data Storage , 2002 , E5.8
Copyright
Copyright © Materials Research Society 2002

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