Ferromagnetic property and synthesis of onion-like fullerenes by chemical vapor deposition using Fe and Co catalysts supported on NaCl

Abstract

Metal-encapsulating onion-like fullerenes (M@OLFs) were synthesized by CVD at relatively low temperature (420°C °) using Fe and Co nanoparticles impregnated into NaCl as catalyst. The morphology and structure of the products were characterized by field emission scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, and Raman spectroscopy. The results show that Fe@OLFs and Co@OLFs with stacked graphitic fragments were prepared using Fe/NaCl or Co/NaCl as catalysts; after Co@OLFs were immersed in concentrated HCl for 48 hours, Co nanoparticles encapsulated by carbon shells were not removed, meaning that carbon shells can protect the encapsulated Co cores against environmental degradation. The coercivity value (750.23Oe) of Co@OLFs showed an obvious magnetic property. Copyright © 2011 Yongzhen Yang et al.