Synthesis, structure and magnetic properties of B2O3/H3BO3-coated Fe nanocapsules

B2O3/H3BO3-coated Fe nanocapsules were synthesized by arc-discharge, evaporating a mixture of Fe micro-powders and B2O3 micro-powders. The results revealed that metallic Fe nanoparticles were uniformly coated with B2O3/H3BO3 shells, and the mean particle size ranged from 30 to 50 nm with ferromagnetic characteristics at room temperature. Thermal gravity analysis indicated that the B2O3/H3BO3 shells effectively protect the Fe cores from oxidation at/below 773 K. The microstructure, growth mechanism and magnetic properties were also investigated.