15:45 〜 16:00
▼ [21p-W611-2] Copper induced hollow carbon nanospheres by arc discharge method: controlled synthesis and formation mechanism
キーワード：arc discharge,hollow carbon nanospheres
Hollow carbon nanospheres with controlled morphologies were successfully synthesized via copper-carbon direct current arc discharge method by alternating the concentration of methane in the reactant gas mixture. A self-healing process to keep the structural integrity of encapsulated shells was evolved gradually with the adding of methane gas from 0% to 20%. The outer graphitic layers expanded and grew to be large fluffy nanospheres further with high methane concentrations from 30% to 50%. A self-repairing function by the reattachment of broken graphitic layers initiated from near-electrode space to the distant was also distinctly exhibited. By comparing several comparable metals (e.g., copper, silver, gold)-carbon arc discharge products, a catalytic carbon-encapsulation mechanism combined with a core-escaping process has been proposed. Specifically, on the basis of the experimental results, copper could be applied as a unique model for both the catalysis of graphitic encapsulation and the adequate template for the formation of hollow nanostructure.