Synthesis and magnetic property of boron nitride nanocapsules encaging iron and cobalt nanoparticles

Boron nitride (BN) nanocapsules encaging Fe or Co nanoparticles were synthesized by using Fe4N/B or Co(NH3)6Cl3/KBH4 powders as raw materials, respectively. The Fe4N was reduced to α-Fe during annealing at 1000 °C for several hours with flowing 100 sccm N2 gas, and the reaction was predicted by Ellingham diagram. Co nanoparticles with BN layers were also produced by annealing the powders at 1000 °C in nitrogen atmosphere. These BN nanocapsules with magnetic nanoparticles exhibited soft magnetic characteristics and good oxidation resistance.