Molecular dynamics simulation on carbon nanotube bundles sandwitched between Si surfaces

Abstract

Distortion and friction of bundle of SWCNT(10,10) sandwiched between two hydrogen-terminated Si(1,1,0) surfaces are investigated by molecular dynamics simulation. After reaching the equilibrium state, a compressive force is applied to the carbon nanotubes until structural destruction appears on carbon nanotubes or substrates. Friction of the system is then investigated when the upper substrate slides along X direction under no load and high load conditions. Distortion of carbon nanotubes can be observed during loading process and no structural destruction occurs even under the pressure as high as 3.8GPa because of their flexibility. Bundles of SWCNT (10,10) roll randomly and slightly under no pressure condition, but exhibit slide-and-roll combined motion under 3.8GPa pressure. The results also show relatively low lateral forces in both cases. The low friction is attributed to the relatively weak Lennard-Jones interaction between substrate and carbon nanotubes with no hanging bond. Excellent performance is therefore expected when carbon nanotubes without defects are used as lubricant or addictives.