Molecular Dynamics Study of Hydrogen Self Diffusion in Metal Decorated Single-Walled Carbon Nanotubes

Since the lack of proper hydrogen storage media is one of the industrial important problems, hydrogen adsorption on carbon nanotubes is an active research field [1]. In comparison with the static properties of adsorbed hydrogen in single-walled carbon nanotubes (SWNTs), the dynamical properties of hydrogen molecules under confinement to these quasi-one dimensional systems have been less studied [2]. The porous membranes permeability and selectivity for gas separations are controlled by the adsorption and diffusion characteristics of adsorbed gas in the membrane material. Diffusion can be characterized by calculating diffusion coefficient. The individual molecules diffusion is described by the self diffusity (Ds), which quantifies the mean square displacement time dependence of a molecule. Molecular simulation methods have shown to provide useful insights into the static and dynamical properties of the fluids confined in micropores [2,3]. The aim of this work is studying the self diffusity of hydrogen in (8,0) platinum/palladium decorated SWNTs through the mean square displacement, at different temperatures and pressures using molecular dynamics simulation.