TAILORING MORPHOLOGY AND MAGNETIC PROPERTIES OF CoPt3 NANOPARTICLES PREPARED VIA REVERSE MICELLES

 

GH.Bahmanrokh1*, M.B.Hashim1,2, I.Ismayadi2, I.R.Idza1, M.S.E.Shafie2, N.Rodziah1, A.R.Norailiana1, A.N.Hapishah1, M.I.Fazidah2, M.Masoudi1, M.Masni1

 

1Department of physics, faculty of Science, University Putra Malaysia,

43400, Serdang, Selangor Malaysia,

 

2Advanced Materials and Nanotechnology Laboratory, Institute of Advanced Technology, University Putra Malaysia, 43400, Serdang, Selangor, Malaysia

*

Corresponding author: ghazalehbahmanrokh@yahoo.com

 

 

ABSTRACT

 

Magnetic nanoparticles with an average size of 11 nm have been prepared by using reverse micelle solutions. The effect of gold coating on the morphology and magnetic properties of cobalt-platinum nanoparticles were investigated by X-ray powder diffraction, energy dispersive x-ray, transmission electron microscopy and vibrating sample magnetometry. Nanoparticles that had useful magnetic properties needed to be protected from oxidation to avoid degrading the favorable magnetic properties. CoPt3 nanoparticles showed a blocking temperature of 40K and coercivity of 261.6Oe. Gold coating of CoPt3 cores with a shell thickness of 5nm further enhanced blocking temperature and coercivity to 45K and 421.1Oe respectively.

 

Keywords: core-shell; magnetic nanoparticles; coercivity; reverse micelle; superparamagnetism

 

 

References

 

[1].             C. L. Dennis, et al., Magnetics, IEEE Transactions on, 43, (2007) 2448-2450.

[2].             E. del Barco, J. Asenjo, X.X. Zhang, R. Pieczynsky, A. Julia, J. Tejada,R.F. Ziolo, D. Fiorani, A.M. Testa, Chem. Mater. 13 (2001) 1487.

[3].             Tartaj P, Tartaj J. ChemMater, 14 (2002) 536 541.

[4].             A.-H. Lu, W. Li, E.-L. Salabas, B. Spliethoff, F. SchVth, Chem.Mater. 18, (2006) 2086.

[5].             J. Penuelas, et al., Surface Science, 602, 2008 545-551.

[6].             Liu JP: Nanoscale magnetic materials and applications: Springer Verlag, 2009.