Production of fullerenes by high-temperature pulsed arc discharge

Fullerene synthesis from carbon powder using CW-CO 2 laser

“…The time period and temperatures of the plumes determined in our experiments were in agreement with similar values previously found in C 60 synthesis methods. Previous experiments and discussions by other research groups have suggested that it is important for the carbon vaporization by the laser to be kept at temperatures over 1000 °C for longer than a time of 400 microseconds 15,16 to undergo the reformation into C 60 . Figure 9 Plumes images of process.…”

“…If a large quantity of vaporized carbon species is produced, such as in the continuous arc discharge method 1 , He-gas is the appropriate buffer gas. When only small quantities of the vaporized carbon species is produced, such as in nanosecond-pulsed Nd:YAG laser ablation 3 or millisecond-pulsed arc discharge methods 16 , Ar-gas is the appropriate buffer gas. The SEM observation of the laser-irradiated carbon-powder showed that the surface morphology changed to be more smoother after irradiation but the grain size remained of the order of micrometers.…”