High magneto- crystalline anisotropy (ku=7×106j/m3) of L10-FePt nanoparticles are an excellent candidate for ultra high-density magnetic recording. The 4 nm FePt nanocrystals were prepared by superhydride reduction of FeCl2·4H2O and Pt(acac)2 precursors in the phenyl ether by reduction of the 1, 2-hexadecanediol and LiBEt3H superhydride. The crystal and magnetic structures were studied by XRD and VSM analysis. By TEM and EDS analyses the size distribution and molar concentration of Fe/Pt of the nanoparticles were determined. The results showed that the particles are first superparamagnetic before heat treatment and then a phase transition accrue from disorder fcc to order fct structure after annealing. Finally, the phase transition leads the magnetic anisotropy of hard FePt nanoparticles to increase to 7 kOe.


1. S Wang and A Taratorin, “Magnetic Information Storage Technology”, Academic Press (1999) 177.
2. D Sellmyer and R Skomski, “Advanced Magnetic Nanostructures”, Springer (2006( 239.
3. S Sun, E Fullerton, D Weller, and C B Murray, IEEE Transactions on Magnetics 37 (2002) 1239.
4. S Sun, Advanced Materials 18 (2006) 393.
5. H Zeng, J Li, J P Liu, Z L Wang, and S Sun, Nature 420 (2002) 395.
6. M Ghidini, G Asti, R Pellicelli, C Pernechele, and M Solzi, J. Magn. Magn. Mater. 316 (2007) 159.
7. Y Ding, S A Majetich, J Kim, K Barmak, H Rollins, and P Sides, J. Magn. Magn. Mater. 284 (2004) 336.
8. J P Liu, K Elkins, D Li, V. Nandwana, and N Poudyal, IEEE Trans. Magn. 42 (2006) 3036.

ارتقاء امنیت وب با وف ایرانی