Dislocation Dynamics in Multiwalled Carbon Nanotubes

PRL 100, 035503 (2008)  Jianyu Huang, Feng Ding, Boris I. Yakobson  

Dislocation dynamics dictate the mechanical behavior of materials. Dislocations in periodic crystalline
materials have been well documented. On the contrary, dislocations in cylindrical carbon nanotubes, particularly in multiwalled carbon nanotubes (MWCNTs), remain almost unexplored. Here we report that a room temperature 1/2 [0001] sessile dislocation in a MWCNT becomes highly mobile, as characterized by its glide, climb, and the glide-climb interactions, at temperatures of about 2000 C. The dislocation glide leads to the cross-linking of different shells; dislocation climb creates nanocracks; and the interaction of two 1/2 [0001] dislocations creates kinks.We found that dislocation loops act as channels for mass transport. These dislocation dynamics are drastically different from that in conventional periodic crystalline materials due to the cylindrical, highly anisotropic structures of MWCNTs.