Formation of polyhedral graphite particles by high-density carbon arc discharge with ethanol vapor

Polyhedral graphite (PG) particles that have a structure composed of many polyhedra with 100 nm −1 μm diameters were formed by using a modified arc discharge method (high-density carbon arc discharge method). The high-density carbon arc discharge was maintained by pyrolysis of ethanol during sublimation of a carbon anode. In this study, we investigated the most effective conditions for forming PG particles in high-density carbon arc plasma with ethanol vapor. We found that diameters of PG particles depended on arc current and that PG particles were effectively formed by using the high-density carbon arc discharge method. Furthermore, results of heat treatment at 2000 °C indicated that the obtained PG particles were graphitized well and that surfaces of the particles with diameters over 400 nm tended to peel off. Compared with the conventional laser vaporization method, the newly developed high-density carbon arc discharge method does not require an expensive equipment and high-pressure atmosphere gas, and is easy to scale up for mass production of PG particles.