DOUBLE-WALLED CARBON NANOTUBE, ALIGNED DOUBLE-WALLED CARBON NANOTUBE BULK STRUCTURE, AND PROCESS FOR PRODUCTION OF THE CARBON NANOTUBE OR THE BULK STRUCTURE

摘要

Disclosed is an aligned double-walled carbon nanotube bulk structure which comprises multiple aligned double-walled carbon nanotubes and has a height of 0.1 μm or more. In the bulk structure, the double-walled carbon nanotubes can be produced by chemical vapor deposition (CVD) in the presence of a metal catalyst having a controlled particle size and a controlled thickness, preferably in the presence of water. It becomes possible to provide a double-walled carbon nanotube which is free from the catalyst contamination, has a high purity, is easy to control the alignment or growth, can be formed through the formation of a bulk structure, and has an excellent electron-emitting property (particularly, a bulk structure of aligned, double-walled carbon nanotubes) and also provide a technique for production of the carbon nanotube.