Growth Analysis of Single-Walled Carbon Nanotubes Based on Interatomic Potentials by Molecular Dynamics Simulation

Molecular dynamics simulation was performed to understand the growth mechanism of single-walled carbon nanotubes (SWNTs) by using the Brenner–Tersoff potential as the interaction among carbon atoms (C–C) and the Tersoff-type potential as the interaction between carbon and metal (C–M) and between metal and metal atoms (M–M). The potential functions for C–M and M–M bonds were established from the results of ab initio calculations. The growth of high-quality SWNTs was simulated at a suitable temperature and supply ratio of carbon atoms. The potential energy of carbon atoms was strongly dependent on the number of C–C and C–M bonds. The dependence explains the growth process, including cap formation, its lift-off, and the continuous SWNT growth.