HRTEM and Raman study of onion-like fullerenes encapsulated Fe

Onion-like fullerenes (OLFs) encapsulated Fe have been synthesized by chemical vapor deposition (CVD). The samples have been characterized by HRTEM and Raman methods. The diameters of OLFs encapsulated Fe are in the range from 15 to 40 nm with pure Fe particles. HRTEM and Raman spectra show that OLFs are highly graphite. XRD spectrum shows Fe nanoparticles are protected in OLFs and are not oxidized by air. It is the stain of graphene shells and the uneven size of OLFs encapsulated Fe that causes the Raman spectra to shift downward slightly from 1580 cm−1.