Preparation of Fullerenes by Arc Discharge between Graphite Anode and Tungsten Cathode

Effects of Gas Species

Abstract

The He, Ar and the Penning gas pressure effects on the preparation yields of the fullerenes were investigated by means of the arc discharge method using graphite (PGX) anode buried in a tungsten rod and tungsten cathode for collector radii of 50mm. The maximum yield showed about 13-14% at 67kPa in He gas. The yields in the mixtures of He and Ne gases (the Penning effect) were similar to those obtained in He gas. Weight ratios of C₆₀ to (C₆₀+C₇₀) were about 20% in Ar gas, while those in He and Penning gas were about 60%. Ultra sonic vibration was effective to separate C₇₀ from soot.