Thermal-loading-induced tunable flattening dynamics of flexible single-walled carbon nanotubes

Non-equilibrium molecular dynamics simulations are performed to investigate the cross-sectional deformation of single-walled carbon nanotubes (SWCNTs) under axial thermal loadings of 0.51–4.65 K A−1. It is shown that, given a thermal loading of sufficient intensity, the initial round cross section of the hot end of the nanotube transits through a series of triangular-like states to a flattened, rectangular configuration. As time elapses, the cross section oscillates between two fully perpendicular flattened states at a frequency which increases linearly with the intensity of the applied thermal load. The diameter of the passing pore within the flattened SWCNT is smaller than that of the original cross section, but is independent of the intensity of the thermal load. The simulation results suggest that the structural deformation of the SWCNT induced by the application of a thermal load can be exploited to realize nanoscale mechanical systems/motors such as nanoclamps, for example, or active fluid transport devices for molecular selection or thermal pumping applications.