Helium adsorption in single wall carbon nanotubes—grand canonical Monte Carlo study

Model calculations of He adsorption at T=4.5 K in an isolated open-ended (12,12) armchair carbon nanotube are presented. The influence of heterogeneity of the tubes wall on adsorption parameters (storage capacity, energy of adsorption and structure of the adsorbed layers) is studied, by comparing the results of grand canonical Monte Carlo (GCMC) simulations for smooth and rough wall models. When the potential used takes into account the corrugation of nanotube surface, He monolayer incommensurate with the sublying graphite sheet is observed and different metastable structures can be stabilized on adsorption and desorption.