Synthesis and characterization of Fe/C core–shell nanoparticles

Carbon-encapsulated Fe nanoparticles have been successfully synthesized by a two-step procedure method of hydrothermal and subsequent thermal reduction process. The introduction of hydrogen atmosphere helps to obtain pure α-Fe phase and the lower annealing temperature (at 550 °C). The morphological characterization indicates that the nanoparticle presents a quasi-spherical shaped, core–shell structure with diameter ranged from 10 to 20 nm and a carbon shell of about 4 nm. The results of X-ray diffraction and Raman spectrum demonstrate that carbon in the as-synthesized product is in amorphous phase. Magnetic measurements reveal the ferromagnetic behavior of the product.

► Fe/C core–shell nanoparticles have been synthesized by a two-step procedure. ► The nanoparticles show a quasi-spherical shaped, core–shell structure with diameter ranged from 10 to 20 nm and a carbon shell of about 4 nm. ► The introduction of H2 helps to achieve lower annealing temperature of 550 °C to obtain Fe phase. ► Hydrogen atmosphere facilitates the formation of pure α-Fe phase while annealing.