Thermodynamics and structure of hydrogen, methane, argon, oxygen, and carbon dioxide adsorbed on single-wall carbon nanotube bundles

Nanoscale pressure effects in individual double-wall carbon nanotubes

“…Evidence of H 2 SO 4 partly ordered around CNTs has been recently reported 34 and the formation of structured water and other species has been considered. 33 In this paper, we present for the first time clear experimental results which show that surface interaction effects at the nanometric scale can lead to a change of up to 50% in the stress transmission using DWCNTs. We observe differences in the pressure behavior of DWCNTs as a function of pressure transmitting medium.…”

“…29 This indicates that the lateral stress due to anisotropic interaction of the molecules of the pressure medium with the tube wall does not play an important role here. The density of the medium around the tube has already been investigated: Bienfait et al 33 conclude from molecular dynamics simulations that argon adsorbs epitaxially on the hexagonal lattice of the tube walls. The density of Ar atoms around a tube is high.…”

Effects of Surface Curvature and Surface Strength on Argon Adsorption in Carbon Nanotubes at Temperatures below the Triple Point

“…The isosteric heat of argon adsorption in cylindrical pores has been studied both experimentally and theoretically (Wilson et al 2002;Yoo et al 2002;Bienfait et al 2004;Jakubek and Simard 2004;Urban et al 2005;Do et al 2008a). However, all of these studies dealt with bundles of SWCNTs and MWCNTs, where the initial isosteric heat is due to adsorption in the interstices between the tubes and in the grooves on the boundary of the bundle (Urban et al 2005).…”

“…182 meV in the low-coverage region, which is comparable to that of nitrogen. Bienfait et al (2004) measured argon adsorption isotherms, heats of adsorption and neutron diffraction, and observed that adsorption first occurred on high-energy binding sites (grooves and interstitial channels), and then on the outer rounded surface of the bundles. Jakubek and Simard (2004) reported the formation of two condensed phases of argon adsorbed onto single-walled carbon nanotubes and found the critical pressures of the onset of the quasi-one-dimensional linear phase and the quasi-two-dimensional monolayer phase formation on the external surface at 77 K and 87.3 K, respectively.…”

Thermodynamic properties and correlation functions of Ar films on the surface of a bundle of nanotubes

“…1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18 This subject has been reviewed recently. 13,14 The adsorption of these gases can occur within the tubes only if they are open, which is possible either during the process of nanotube formation (e.g., when endohedral C 60 molecules are formed), 15 or after chemical treatment to open the tubes.…”