▎ 摘　　要

NOVELTY - Preparing carbon nanotube or graphene nano carbon material, comprises: (i) cleaning dirt on the surface of silicon carbide sample by using solution chemistry method; and (ii) preparing carbon nanotube or graphene nano carbon material by placing processed silicon carbide sample in vacuum cavity, maintaining vacuum degree at 10-4 to 10-10 mbar for graphene nano carbon material production/10-4 to 108 mbar for carbon nanotube production, heating silicon carbide sample, and then cooling the sample to the room temperature. USE - The method is useful for preparing carbon nanotube or graphene nano carbon material. ADVANTAGE - The method prepares high purity nano carbon material, which overcomes the influence of the metal on the fundamental physical and chemical properties of the nano carbon material; and efficiently prepares the nano carbon material with good repeatability. DETAILED DESCRIPTION - Preparing carbon nanotube or graphene nano carbon material, comprises: (i) cleaning the dirt on the surface of silicon carbide sample by using a solution chemistry method; and (ii) placing the processed silicon carbide sample in a vacuum cavity, where the cavity is vacuum pumped till the vacuum degree is less than or equal to 5x 10-10 mbar, or inertia or reducibility gas is filled into the vacuum cavity after pumping, so that the vacuum degree stays at 10-4 to 10-10 mbar, heating the silicon carbide sample to 1300-2000 degrees C, preserving the temperature for more than 3 minutes, and then cooling the sample to the room temperature in inertia or reducibility gas to obtain graphene, or placing the processed silicon carbide sample in the vacuum cavity, where the vacuum degree is less than or equal to 5x 10-10 mbar, after vacuum pumping, and then the filling oxygen containing gas into the vacuum cavity to maintain the vacuum degree at 10-4 to 108 mbar, heating the silicon carbide sample to 1300-2000 degrees C, preserving the temperature for more than 3 minutes, and then cooling the sample to the room temperature in inertia or reducibility gas to obtain the carbon nanotube.