Fullerenes growth process

CNTs can be chemically functionalized to achieve good dispersion in polymer/ CNT composites and strong interface adhesion (Gao et al., 2004). CNTs can be assembled as ropes or bundles, and there are some catalyst residuals, bucky onions, spheroidal fullerenes, amorphous carbon, polyhedron graphite nanoparticles, and other forms of impurities during the growth process of CNTs. 

At the end of this section, let us return briefly to the spectra shown in Fig. 3. Notice the structure in the mass spectrum of QoCa, between the completion of the first metal layer at 32 and the second at 104. This structure is identical in the fragmentation mass spectra of fullerenes covered with Ca and with Sr. It is reminiscent of the subshell structure of pure Ca clusters. The subshells could be correlated with the formation of stable islands during the growth of the individual shells[10,l 1]. The sublayer structure we observe here may also give some clue to the building process of these layers. However, the data is presently insufficient to allow stable islands to be identified with certainty. 

To produce fullerenes and metallofullerenes, a temperature above 800 °C was found to be necessary, and below this critical temperature no fullerenes were produced (Haufler et al., 1991 Suzuki et al., 1997a Wakabayashi et al., 1997), suggesting that relatively slow thermal annealing processes are required to form fullerenes and metallofullerenes. The laser-furnace method is suited to the study of growth mechanism of fullerenes and metallofullerenes (Curl and Smalley, 1991 Haufler et al., 1991 ... 

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