Mimetic Synthesis and Characterization of Templated Mesoporous Materials Using Molecular Simulation

摘要

A first approach towards prediction of templated porous materials structure is proposed using equilibrium properties of surfactant-solivent-silica liquid crystal systems. Phase behavior of these mixtures under no polymerization conditions is studied using lattice Monte Carlo simulations. Phase separation of the ternary system is observed when surfactant-silica interactions are stronger than surfactant-solvent interactions. Liquid crystal structures in the high-surfactant-high-silica phase depend on the overall composition of the system. The range of structures obtained is in qualitative agreement with experimental observations: hexagonal phases are observed at low surfactant/silica ratios and lamellar phases are observed at high surfactant/silica ratios. Adsorption properties on model materials were calculated using grand canonical Monte Carlo simulations. Heats of adsorption profiles are similar to experimental ones indicating adsorbent heterogeneity.