Abstract: Carbon-coated Fe nanocrystals were produced by d.c. carbon arc method by using a composite anode of Fe₂O₃ and graphite. The investigations for the
effect of different Fe₂O₃ contents in the composite graphite rods on the morphology, structures and diameter distribution of graphite-encapsulated Fe nanocrystals were
carried out. X-ray diffraction of the carbon soot produced from Fe₂O₃-containing composite anode indicated the presence of graphite phase and α-Fe, no evidence of
Fe oxides was observed, but a small amount of Fe₃C found. The effect of He pressure and Fe₂O₃ content on the C_60/70 yield of the carbon soot produced from
composite rods was also discussed. The results show that the quantity and the diameter distribution of carbon-coated Fe nanocrystals are determined by the Fe₂O₃ content in
the composite anode rod. He pressures are the major factor of affecting C_60/70 yield produced from Fe₂O₃ composite anode, but not the major factor of affecting the yields
of carbon-coated Fe nanocrystals. The relationship of C_60/70 yields in the carbon soot produced from Fe₂O₃ composite anode and He pessure is markedly different from that
of pure graphite anode.

Key words: carbon-coated Fe nanocrystals, carbon arc method, C_60/70