Monte Carlo simulations of H-2 physisorption in finite-diameter carbon nanotube ropes

We report the results of classical, grand canonical Monte Carlo simulations of the physisorption of H-2 in finite-diameter 'ropes' of parallel single- walled carbon nanotubes. The strong dependence of the gravimetric adsorptio n on the diameter of the rope is correlated with computed values of the spe cific surface area. The grooves on the external surfaces of the ropes are s hown to provide a high binding-energy adsorption site, comparable in streng th to those in the endohedral pores. Our results suggest that delamination of nanotube ropes should increase the gravimetric storage capacity. (C) 200 0 Elsevier Science B.V. All rights reserved.