Morphology change of multi-walled carbon nanotubes with SiC coating by electron irradiation

The different behaviour between morphology changes of multi-walled carbon nanotube (MWNT) and MWNT with SiC coating was investigated by electron irradiation. High resolution TEM images revealed that deformation of graphitic shells occurred in both MWNT and MWNT with SiC coating by electron irradiation. Electron irradiation began changing the outer and inner diameters of MWNT within 3 minutes exposure, whereas it began changing the diameters of MWNT with SiC coating after 10 minutes exposure. The outer diameter of MWNT increased up to irradiation time of 9 min and then decreased rapidly. On the other hand, the outer diameter of MWNT with SiC coating increased up to irradiation time of 50 min and then was almost saturated. These results lead that the morphology stability of MWNT against electron irradiation can be improved by coating with the SiC layer on MWNT.