Uniform carbon spheres of high purity prepared on kaolin by CCVD

摘要

Carbon spheres with diameters of 400-2000 nm were synthesized using transition metal (TM) supported on kaolin catalysts by CCVD in large quantities. The synthetic reaction was carried out at temperature higher than 650 deg C. The as-synthesized carbon spheres can be purified and separated by the flow of N_2 and C_2H_2 gases at 200 and 50 sccm, respectively. The carbon spheres are composed of unclosed graphene layers with interlayer distances of 0.33-0.35 nm between the layers. The carbon spheres were found to e thermally stable in air and no endothermic or exothermic phenomena were found in N_2 atmosphere at temperature lower than 500 deg C.