Silicon inclusion effect on fullerene formation under induction thermal plasma condition

The radio frequency inductively coupled thermal plasma (RF-ICTP) was used to fabricate fullerenes (C-60,C-70 etc.) by direct evaporation of C or C-Si mixed powder by high enthalpy of the plasma. Spectroscopic observation of the plasma was made for molecular band spectra of C-2 and atomic lines of C. The formation of fullerenes C-60 and C-70 as well as higher fullerenes was checked and recognized by TFMS (Time of Flight Mass Spectrometer). The results showed that Si mixing into C powder could increase the radiation intensity of C, molecular as well as C atomic spectrums and decrease the plasma temperature, and showed a higher synthesis rate of fullerenes including higher order one, compared to pure C powder case. Discussions were made about the effects of O-2 inclusion (from air leak) as well as Si injection on the concentrations of the C particle system (C, C-2, C-3, C-4 etc.), and the influence of Si injection on the plasma temperature was also involved. (C) 2002 Elsevier Science B.V. All rights reserved.