| abstract |
Fullerenes are a novel material that has been expected to serve as a promising material in the construction of organic devices. However, the electric conductivity of fullerenes, which has been, reported heretofore spreads over a wide range including values corresponding to insulators as well as those corresponding to semiconductors. The present invention makes it possible to improve the conductivity of fullerenes highly reproducibly by heating the fullerenes at a specified temperature in an inert gas which is flowed under a specified condition, that is, by controlling the concentration of impurities, particularly oxygen and water adsorbed to the fullerenes. |