Yongsheng Yu1

1, Harbin Institute of Technology, Heilongjiang, , China

Monodisperse ferrimagnetic CoxFe3-xO4 nanoparticles (NPs) are synthesized through chemical methods which are readily dispersed in hexane, forming stable ferrimagnetic NP dispersion and allowing easy NP self-assembly. When assembled under an external magnetic field, these NPs show the preferred magnetic alignment with their Hc reaching 2.49 kOe. 1, 2
Chemical synthesis of L10-FePtAu NPs will be also introduced. The highest Hc of 12.2 kOe can be achieved, which is much higher than the Hc reported by the previous studies on solution-synthesized FePt NPs. The phase separation between Au and FePt phase likely is the main reason for the ordering of FePt phase. The reported one-pot synthesis of L10-FePtAu NPs may provide an ideal class of building blocks for magnetic energy and data-storage applications.3
In addition, we also report a new approach for preparation of exchange-coupling L10-FePt/Fe nanocomposite magnets with gradient interface between hard phase and soft phase4 and L10-FePd/Fe nanocomposite magnets with controllable morphology and compositions5. These works provide a general approach to L10-FePt(Pd)/Fe nanocomposite magnets for understanding exchange-coupling in nanoscale.
1.Y. S Yu et al. Advanced Materials 2013, 25, 3090-3094
2.Y. S Yu et al. Nanoscale 2015, 7, 2877-2882
3.Y. S Yu et al. Nanoscale 2014, 6, 12050-12055
4. Y. S Yu et al. Journal of Materials Chemistry C, 2015, 3, 7075-7080
5.Y. S Yu et al. Nano Letters, 2013, 13, 4975-4979