Thermal-induced edge barriers and forces in interlayer interaction of concentric carbon nanotubes.

Molecular dynamics simulations reveal that thermal-induced edge barriers and forces can govern the interlayer interaction of double walled carbon nanotubes. As a result, friction in such systems depends on both the area of contact and the length of the contact edges. The latter effect is negligible in macroscopic friction and provides a feasible explanation for the seemingly contradictory laws of interlayer friction, which have been reported in the literature. The temperature-dependent edge forces can be utilized as a driving force in carbon nanotube thermal actuators, and has general implications for nanoscale friction and contact.