Fullerene filling modulates carbon nanotube radial elasticity and resistance to high pressure
Abstract
The high pressure behavior of carbon nanotubes (CNTs) filled with fullerenes (C60@CNTs) is investigated systematically using molecular mechanics and molecular dynamics simulations. It is shown that the C60 filling can increase the transition pressure (Pc) of intrinsic CNTs and optimize the radial elasticity of CNTs. The C60 filling increases the Pc of CNT(17, 0) by a factor of ∼25, and the Pc of CNT(10, 10) by a factor of ∼5. An inelastic CNT(17, 0) can be transformed into a superelastic CNT(17, 0) by filling C60 into CNTs. Moreover, C60@CNTs with larger diameters (21.76 Å > d > 13.56 Å) show the better radial elasticity compared with intrinsic CNTs. These characteristics can make C60@CNTs possess potential applications in pressure sensors, electromechanical oscillators, nanotube memory etc. In addition, C60@CNTs with larger diameters (21.76 Å > d > 13.56 Å) undergo two structure transitions under high pressure, which is well in agreement with the experimental results. The Lennard–Jones potential can describe the interaction between C60 and CNT well and explain radial collapse and recovery properties of C60@CNT completely, which can provide theoretical guidance for experimental results.