The inner nano-space control of carbon nanotubes using collisionless different-polarity ion plasmas
Résumé
An original approach based on plasma-ion irradiation method has been performed in order to control the inner nano-space of single-(SWNTs), double-(DWNTs), and multi-walled (MWNTs) carbon nanotubes and resultantly develop novel functional carbon-based nano-materials. When positive bias-voltages are applied to a substrate covered with these carbon nanotubes and immersed in a collisionless different-polarity ion plasma [alkali-fullerene (Cs+ - C60-) plasma], the SWNTs and DWNTs encapsulating fullerene molecules are clearly observed, and the fullerene filling efficiency is found to become enhanced in the order MWNTs, DWNTs, SWNTs. In the case of negative bias application, the Cs encapsulation inside the SWNTs is directly observed for the first time, the configuration of which is demonstrated to comprise three varieties. Finally, when the bias-voltage with polarity change is sequentially applied to the SWNTs, the SWNT encapsulating a junction of Cs atoms on one side and C60 molecules on the other is for the first time observed.