ELECTROCHEMICAL MECHANISM FOR FULLERENE FORMATION IN PLASMA ARCS

During the synthesis of fullerenes by dc plasma arcs, it has been foun d that the anodic graphite rod consistently burns up, while the cathod ic graphite rod grows slag at its end. Further investigations revealed that the anodic and cathodic graphite rods played different roles in forming fullerenes in plasma arcs. The anodic graphite rod contributed to the formation of all products in de plasma arcs, while the cathodi c one played a role only as an electrode. These results suggest that a n electrochemical mechanism occurs during fullerene formation in plasm a arcs. Temperature measurements indicate that, in the stable plasma a re in our experiment, the temperature of the graphite rods was lower t han their sublimation point, thus confirming the involvement of an ele ctrochemical mechanism in the fullerene formation process in de plasma arcs. The relationship of the fullerene formation rate to the cell vo ltage supports the point.