Abstract: Carbon nano onions ( CNOs ) were high selectively synthesized through chemical vapor deposition method using Ni-Fe metal as catalysts. As harvested CNOs contains metal core inside and hollowed CNOs. Amorphous is formed with the broken of carbon shells through the normal acid wash -burning technology. The magnetic properties of CNOs were analysised and magnetic separating technology was proposed. The results show that CNOs with metal core inside can be separated from the hollowed CNOs efficiently using this method and the purification rate reaches up to 95;.

Key words: Carbon nano onions ( CNOs ) were high selectively synthesized through chemical vapor deposition method using Ni-Fe metal as catalysts. As harvested CNOs contains metal core inside and hollowed CNOs. Amorphous is formed with the broken of carbon shells through the normal acid wash -burning technology. The magnetic properties of CNOs were analysised and magnetic separating technology was proposed. The results show that CNOs with metal core inside can be separated from the hollowed CNOs efficiently using this method and the purification rate reaches up to 95;.