High saturation magnetization FeB(C) nanocapsules

FeB(C) nanocapsules were prepared by arc-discharging Fe80B20 alloy in Ar and CH4. X-ray diffraction and transmission electron microscopy analyses showed that the FeB(C) nanocapsules had a core-shell structure with alpha-Fe and Fe3B as cores and graphite as shells. The formation mechanism of the FeB(C) nanocapsules is discussed. The graphite shells display a strong anti-acid effect. The saturation magnetization at room temperature of the FeB(C) nanocapsules is much higher than that of Fe(B) nanocapsules. The blocking temperature of FeB(C) nanocapsules is above 300 K. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.