Configurational effects of templating on the adsorption isotherms of templated porous materials

The porosity and pore geometry of disordered materials can be influenced by employing a removable template during synthesis. A theoretical and simulat ion study is reported of the configurational effects of template size and d ensity on the adsorption isotherms of templated porous materials. To isolat e the configurational (entropic) contributions, the adsorbate, matrix and t emplate components are modelled as hard spheres. The replica Ornstein-Zerni ke equations proposed by Zhang, L. and Van Tassel, P. R. (2000) J. chem Phy s., 112, 3006 are used within the Percus-Yevick approximation to calculate adsorption isotherms for differently sized adsorbate and template component s. These theoretical results are compared with results from Monte Carlo sim ulation. It is found that adsorption is most enhanced whenever the size of the template is equal to or slightly larger than that of the adsorbate. Als o, for systems of constant matrix density or constant matrix plus template density, increasing the density of template enhances the adsorption.