Synthesis of Magnetic Nanoparticles toward High-Performance Permanent Magnets

The energy product (BH)max, which indicates the performance of the magnetic materials, had been drastically improved until the strongest magnet Nd2Fe14B magnet was developed. Recently, it has been strongly desired to develop new magnetic materials with higher saturation magnetization and higher anisotropy field than Nd2Fe14B. On the other hand, an exchange-coupled nanocomposite magnet composed of a soft magnetic phase with high saturation magnetization and a hard magnetic phase with high coercivity has been expected to show larger (BH)max than the conventional Nd2Fe14B. The development of effective exchange coupling requires precise control of the soft magnetic phase and the hard magnetic phase at the nanoscale, and the creation of high-performance nanoparticle-based exchange-coupled nanocomposite magnets has attracted much attention.


Synthesis of Rare Earth Magnetic Particles


Nanoparticle Approach to the Formation of Sm2Fe17N3 Hard Magnetic Particles （Chem. Lett. 2019, 48, 1054.）

Synthesis of Exchange Coupled Nanocomposite Magnet Nanoparticles


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Conversion of Anisotropically Phase-segregated Pd/γ-Fe2O3 Nanoparticles into Exchange-coupled fct-FePt/α-Fe Nanocomposite Magnets
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Exchange Coupling Interaction in L10-FePt/α-Fe Nanocomposite Magnets with Large Maximum Energy Products
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Formation of Strong L10-FePt/α-Fe Nanocomposite Magnets by Visualizing Efficient Exchange Coupling
（Nanoscale Adv. 2019, 1, 2598.）