Fullerenes and other structures of carbon synthesized in a carbon plasma jet under helium flow

The plasma chemical reactor based on a carbon plasma jet was created for the production of fullerenes. This reactor has the changing temperature zone and provides deposition of soot under different conditions. X-ray powder diffraction investigation is carried out for identification of substances obtained in different parts of the installation. The fullerene crystals and an amorphous phase were found in the chamber. The amorphous fraction is probably composed mainly of the atomic aggregations similar in size and coordination to the fullerene molecules. The residual graphite and its polytype modifications were also found. This residual graphite is better crystallized than the initial one, therefore, it can be considered as a product of carbon crystallization from plasma but not as the particles of the initial graphite seized from the central electrode, The fullerene and amorphous fractions were not found on the external electrode which was cooled by water and where very fast condensation of carbon from plasma takes place. The sample taken from this electrode is composed mainly from a new x-graphite phase which can be considered a result of this fast condensation, This last conclusion is also supported by the fact that this x-graphite was also found on the walls of the chamber where the fast condensation also must take place, but it was not found in the flying soot fraction. (C) 1999 Elsevier Science Ltd. All rights reserved.