Physisorption of simple gases on C60 fullerene

Experimental adsorption isotherms of nitrogen and argon at 77.4 K and carbon dioxide at 273.2 K on C-60 fullerene have been obtained to characterize the surface of this material. Grand Canonical Monte Carlo computer simulations of nitrogen physisorption have been performed that reproduce the experimental isotherm. Adsorption energy distribution functions calculated from the experimental isotherms of the studied gases are compared with the results obtained from the simulations and with experimental data obtained with other materials such as polycrystalline diamond and two carbon blacks (Vulcan 3-G and Vulcan 9). From the simulations the distributions of adsorbed molecules with respect to their gas-solid energies are discussed. Microdensity profiles are employed to calculate the local adsorption isotherms. Three adsorption sites have been identified, and the isosteric heat of adsorption at zero coverage has been calculated.