Energy transfer mechanisms in gas–carbon nanotube collisions

Abstract

Abstract The molecular dynamics method was used to study the detailed in- and out-of-plane collisional energy transfer mechanisms between Xe/Ne gas atoms and a (10,0) carbon nanotube (CNT). Although the collisional energy transfer over entire collisions was analyzed, this work focuses on the energy transfer mechanisms over individual encounters, and in particular over the first and second encounters of the collisions. Qualitatively similar transfer mechanisms were seen for these encounters, independent of whether they preceded scattering or trapping of the gas atom. It was observed that the change in axial kinetic energy over each encounter is sensitive to the hexagonal structure of the CNT, and that this change can be large over single encounters. However, the ensemble-averaged change in axial kinetic energy is very small. In contrast the change in circumferential kinetic energy over single encounters is small, and is governed by the overall cylindrical shape of the tube and not the microscopic hexagonal structure.