M. Bienfait, P. Zeppenfeld, N. Dupont-Pavlovsky, M. Muris, M.R. Johnson, T. Wilson, M. DePies, O.E. Vilches
Adsorption isotherms, isosteric heats of adsorption, and neutron diffraction measurements of hydrogen, methane, argon, oxygen, and carbon dioxide adsorbed on single-wall carbon nanotube bundles show that all species, except CO2, condense first on high-energy binding sites, such as the grooves and the widest interstitial channels, and then on the outer rounded surface of the bundles. As for CO2, only one set of adsorption sites is observed, which is attributed mainly to the grooves. The diffraction results further reveal that the average packing of the bundles is not changed upon adsorption and that no significant overall bundle dilation is observed on our sample. Molecular dynamic simulations confirm and complete our interpretation.
CRMC2-CNRS, Faculté de Luminy, F-13288 Marseille Cedex 9, Case 901, France; Institut für Experimentalphysik, Johannes Kepler Universitat Linz, A-4040 Linz, Austria; LCSM, Université H. Poincaré, F-54506 Vandoeuvre les Nancy Cedex, BP 239, France; Institut Laue-Langevin, F-38042 Grenoble Cedex 9, BP 156, France; Department of Physics, University of Washington, Seattle, WA 98195-1560, United States; Department of Physics, Makassar State University, 90222 Makassar, Indonesia
