[Show abstract][Hide abstract] ABSTRACT: We perform molecular dynamics (MD) simulations of nanoindentation to study the mechanical properties of a graphene nanoribbon encapsulated in a single-walled carbon nanotube (GNR@SWCNT). The effects of different temperatures, nanotube diameters, and slenderness ratios on the properties of the GNR@SWCNT are examined. Results show that the maximum load and contact stiffness increase with an increase of temperature. But the adhesion force and ratio of springback are low at a high temperature of 1200 K. The maximum load and contact stiffness are high for the nanoindentation of the GNR@SWCNT with a low slenderness ratio. In addition, the GNR@SWCNT has a more than 15% rate of springback exhibiting a superelastic nanocomposite behavior. The results are useful for engineering applications of nanocomposites composed of carbon nanotubes and graphene materials.
No preview · Article · Aug 2015 · Applied Surface Science
[Show abstract][Hide abstract] ABSTRACT: The adsorption of molecular hydrogen on few-layer graphene (FLG) structures is studied using molecular dynamics simulations. The interaction between graphene and hydrogen molecules is described by the Lennard-Jones potential. The effects of pressure, temperature, number of layers in a FLG, and FLG interlayer spacing are evaluated in terms of molecular trajectories, binding energy, binding force, and gravimetric hydrogen storage capacity (HSC). The simulation results show that the effects of temperature and pressure can offset each other to improve HSC. An insufficient interlayer spacing (0.35 nm) largely limits the HSC of FLG because hydrogen adsorbed at the edges of the graphene prevents more hydrogen from entering the structure. A low temperature (77 K), a high pressure, a large number of layers in a FLG, and a large FLG interlayer spacing maximize the HSC.
No preview · Article · Jun 2013 · Journal of Molecular Modeling