Adsorption of binary mixtures on heterogeneous surfaces

BULNES F.; RAMIREZ PASTOR A. J.; RICCARDO J. L.; PEREYRA V.

Brisbane

Conferencia; Proceedings of the second Pacific Basin Conference on Adsorption Science and Technology; 2000

University of Queensland

The adsorption of binary mixtures on heterogeneous surfaces is studied by computer simulation. The process is monitored by following the partial and total adsorption isotherms, adsorption energies, coverage fluctuations and differential heat of adsorption. These quantities are calculated by using Grand Canonical Monte Carlo simulation. Heterogeneous surfaces are represented by two kinas of sites, the so- called bivariate surface. Deep and shallow sites with energies  and  form l x l patches distributed at random or in a chessboard- like ordered domains on two- dimensional square lattices. The partial and total isotherms, as well as other thermodynamics quantities are very sensitive to the surface energy topography, particularly, when repulsive lateral interactions between adsorbed molecules are present.