Quantum contribution to gas adsorption in carbon nanotubes

Recently published Monte Carlo simulation studies have demonstrated that carbon nanotubes could be a new adsorbent material for the storage of gases such as hydrogen. This engineering application suitable for the use of hydrogen in fuel cells has motivated much experimental and theoretical work, including the present work. Using grand canonical Monte Carlo simulations, we have calculated the amount of hydrogen adsorbed in various arrangements of single-walled carbon nanotubes at high pressure and room temperature. For these thermodynamic states, we determined the importance of quantum effects on hydrogen adsorption. These quantum corrections were computed following a perturbative scheme already used, for instance, in simulation studies of phase diagrams of water, neon and methane. Taking into account the quantum corrections, we estimated, for each considered arrangement, the most favorable diameter and relative distance of the nanotubes for hydrogen adsorption.