Polyol Process for Fe-based Hard (FCT-FePt) and Soft (FeCo) Nanoparticles

Fe-Pt nanoparticles: equiatomic FePt nanoparticles with the ordered L1₀ structure is attractive as high-density magnetic recording media. In our recent work, chemically synthesized fcc-FePt nanoparticles with narrow size distribution and their self-assembled array with close-packed microstructure has been achieved successfully. However, the particles coalesced during the subsequent annealing step which is necessary to obtain L1₀ FePt nanoparticles. Later, the authors successfully demonstrated the direct synthesis of L1₀ FePt nanoparticles at low temperatures of 553 K using "modified polyol method" without subsequent annealing, whose diameter is 5-10 nm and intrinsic magnetocrystalline anisotropy field (Hk) of 31 kOe (B. Jeyadevan et al., 2003).