One-pot synthesis of amino functionalized mesoporous silica materials : using simulations to understand transitions between different structures

• Published in: Journal of materials chemistry Vol. 19; no. 6; pp. 724 - 732
• Main Authors: PATTI, Alessandro, MACKIE, Allan D, ZELENAK, Vladimir, SIPERSTEIN, Flor R
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 14.02.2009
• Subjects: Adsorbents; Chemistry; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; General and physical chemistry; Liquid crystals; Physics; Structure of solids and liquids; crystallography; Surface physical chemistry; Monte Carlo method; Purification; Liquid state structure; Inorganic adsorbent; Surfactant; Liquid crystals; Precursor; Chemical modification; Organic-inorganic hybrid materials; Numerical simulation; Crystal-phase transformations; Curvature; Crystalline structure
• ISSN: 0959-9428; 1364-5501
• DOI: 10.1039/b813016g

The rich phase behavior of surfactants can be exploited to design materials with a given desired structure and properties. One example includes amino functionalized mesoporous silicas, which can be used in different environmental applications, including removal of heavy metals from water and CO@d2 separation and purification. These applications may require a high concentration of functional groups, but the increased concentration of hybrid organic-inorganic precursors can lead to the destruction of the liquid crystals or transformation into other phases. In this work, we modeled the phase behavior of such systems using lattice Monte Carlo simulations and analyzed the distribution of hybrid organic-inorganic precursors to explain the observed changes in the lichuid crystal structures. In particular, we observed that if the hybrid precursor is sufficiently hydrophobic, it can act as a cosurfactant, swell the core of the surfactant liquid crystal, and lead to structures with smaller interfacial curvature. On the other hand, if the hybrid precursor acts as a cosolvent it will solubilize the surfactant leading to the destruction of the preformed liquid crystal.