Abstract: Onion-like fullerenes(OLFs) with an external diameter between 15 nm and 35 nm were prepared by vacuum heat-treatment methods of graphite powers using Al as catalyst. Resultant OLFs were purified by removing impurities using CS₂ treatment and air oxidation method. HRTEM, XRD and TGA are applied to analysize samples before and after purification. The results indicate that CS₂ treatment can effectively remove metal catalyst particles. After the succeeding calcination at 610 ℃ for 200 min in air, most of amorphous carbon and graphite pieces are removed, the purity of the OLFs is above 50％(volume ratio).

Key words: Onion-like fullerenes(OLFs), Vaccum heat-treatment, Oxidation, Purification, Structure