Novel FeB49 nanorods homogeneously coated with protective boron nitride sheaths (h-BN-FeB49 nanocomposites) have been synthesized through a simple chemical vapor deposition (CVD) method at 1200 °C by controlling the ratio of Boron/iron trioxide and the heating rate. Detailed electron microscopy studies reveal two kinds of h-BN-FeB49 nanocomposites with different structures and morphologies: one is a sandwich-type structure named BN-FeB-10 [B : Fe2O3 = 10] which is constructed by filling FeB49 nanorods along the growth axes of closed end BN nanotubes; the other is a heterogeneous structure named BN-FeB-5 [B : Fe2O3 = 5] in which FeB49 is coated by h-BN sheets with 4 ∼ 20 layers uniformly, and the h-BN sheets could be exfoliated from BN-FeB-5 using chemical exfoliation with the solvent DMF. The photoluminescence (PL) spectrum shows that the as-prepared products with these special structures have strong emissions in the visible light region. Magnetic measurements show that both kinds of h-BN-FeB49 nanocomposites are hard magnetic materials at room temperature. The growth mechanism and morphology of h-BN-FeB49 nanocomposites are discussed on the basis of the nitridation process.
