Synthesis of encapsulating and hollow onion-like fullerenes from coal

Onion-like fullerenes (OLFs) with different structures were synthesized from coal by radio frequency plasma. The morphologies and structures of the products were characterized by field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray spectroscopy (EDS) techniques. The results clearly indicated that two types of uniform OLFs with high purity could be prepared from coal, and Fe in coal favored the growth of OLFs