High efficiency purification method for multi-walled carbon nanotubes

We remove the impurity and studied the reaction temperature and reagent and the purification methods for multiwalled carbon nanotubes (MWNTs). Defects within the MWNT structure can reduce the effective band overlap and therefore lead to an increase in the material´s electrical resistivity. The main impurities in MWNT are iron particles, amorphous carbon, multishell carbon nanocapsules. The results obtained from Raman spectroscopy and thermogravimetric analysis explain that most defects such as metal or carbon defects can be purified by the proposed method.