Nodular carbon nanotubes and their field emission characteristics

A new configuration of carbon nanotubes (CNTs) has been discovered in our laboratory and their surfaces are fully covered with nano-sized node-like structures. The node structures have almost the same size of 40-50 nm. We refer to this material as the nodular carbon nanotube (NCNT). Field emission scanning electron microscopy shows that after a hydrogen plasma process in our homemade plasma equipment, the common carbon nanotubes were changed into NCNTs. The experimental result demonstrates that this material has good field emission characteristics, low threshold field, stable and suitable emitting current, especially for the emission site density up to the order of 10(6) cm(-2).