Synthesis and characterization of Fe-B nanoparticles for potential magnetic applications

摘要

The crystallization and structure of Fe-B nanoparticles (NPs) of different sizes formed in a single process by gas aggregation from Fe80B 20 targets were analyzed by transmission electron microscopy. It is concluded that all NPs are covered by an amorphous Fe-B shell while the crystal structure of the NPs core depends on their size. Large NPs with diameters ≥30 nm are monocrystalline tetragonal Fe3B, small diameter NPs (≤20 nm) are completely amorphous whereas in middle size NPs, with diameters between 20 and 30 nm, difference Fe-B phases (tetragonal Fe3B and orthorhombic FeB) together with defaulted areas are observed. This work opens new possibilities to produce Fe-B NPs tailoring their magnetic properties by controlling their size and composition. © 2013 Springer Science+Business Media New York.