Ultrafine (30–40 nm) fullerene particles were generated via vapor condensation in a continuous flow system starting from pure C60 and mixed fullerene extract (C60/C70). Gas-phase particle size distributions were measured using a condensation particle counter and differential mobility analyzer. Particle morphology and crystallinity were studied by SEM and TEM. Particles were partly amorphous at 400°C, and became crystalline C60 when processed above 500°C. The particles had an average size of 30, 35 and 40 nm and total number concentrations of 2.2×106, 3.5×106, and 5.0×106 number of particles/cm3, respectively at 500, 525 and 550°C.
Gurav, A., Kodas, T., Wang, L-M., Kauppinen, E., & Joutsensaari, J. (1994). Generation of nanometer size fullerene particles via vapor condensation. Chemical Physics Letters, 218(4), 304-308. https://doi.org/10.1016/0009-2614(93)E1491-X