Influence of defects on friction and motion of carbon nanotube

Abstract

Motion and friction of carbon nanotubes with vacancy defects or Stone-Thower-Wales (STW) defects on them are investigated in commensurate states and incommensurate states by molecular dynamics simulation. Results show that defects lead to incommensurate state in part of interfaces, thus decreasing the friction. More amount of STW defects would cause larger distortion of carbon nanotube, smaller lateral force amplitude, more local incommensurate state of interfaces and smaller friction. The friction of carbon nanotube with vacancy defects is obviously larger than carbon nanotube with STW defects. The reason is that the carbon nanotube with vacancy defects will change its motion in later period of motion, which can increase energy dissipation. Defects barely have influence on the friction of carbon nanotubes in incommensurate state because interfaces are all in incommensurate state whether they are having defects or not.