Organic-inorganic Hybrid Mesoporous Materials Research Articles

Organic-Inorganic Hybrid Mesoporous Materials Assembled from Sodium Silicate and Organotrialkoxysilane

The MSU-typed mesoporous organosilica with organic methyl, vinyl, and phenyl functionals were prepared by using inexpensive sodium silicate and organotrialkoxysilane as the silica precursor and nonionic polyethyleneoxide AEO(9)[C11- H-15(23-31)(CH2CH2O)(9)H] as the structure-directing agent. The resultant materials were characterized by powder X-ray diffraction (XRD), N-2 sorptometry, high resolution transmission electron microscopy (HRTEM) and Si-29 CP MAS-NMR. The results indicated that addition of sodium fluorite reduced the possibility of organotrialkoxysilane with small organic group entering the framework walls of the mesostructures at neutral condition. Moreover, pore diameter of material increased upon the increase of pH value.

Ordered mesoporous organic-inorganic hybrid materials containing microporous functional calix[8]arene amides.

Ordered mesoporous organic-inorganic hybrid materials containing microporous functional calix[8]arene amides have been synthesized and characterized for the first time, and are shown to be effective in removal of trace humic acid contaminant from water.

Tuning of particle morphology and pore properties in mesoporous silicas with multiple organic functional groups.

A synthetic method has been developed that can control both multifunctionalization and morphology of the mesoporous organic-inorganic hybrid materials by introducing different molar ratios of organoalkoxysilane precursors to a base-catalyzed co-condensation of silicate.

Organic-Containing Mesoporous Silicas with a Variety of Mesophases and a Periodic Pore Wall Structure

AbstractIn this report we introduce new types of organic-inorganic hybrid mesoporous materials, in which organic and inorganic moieties are distributed homogeneously at the molecular level in the framework, forming a covalently bonded network. Possessing unique surfaces on which both organic and inorganic components are exposed, these materials are expected to have applications in various areas as catalysts, adsorbents and separators, and as hosts for nano-cluster synthesis. The hybrid mesoporous materials showed not only unique surface properties but also unique structural features in micron- or angstrom-scales. Mesoporous materials containing ethylene groups in the main framework formed a variety of particle morphologies of hexagonal rod, spherical, and decaoctahedral shapes in the sizes of 1-10 μm. Mesoporous material containing phenylene groups showed novel crystal-like 7.6 Å periodicity in the pore walls. The mesoporous material has periodically arranged hydrophobic-hydrophilic surfaces, which is a great advantage for use as catalyst and host material for inclusion chemistry.

Hybrid ethane–siloxane mesoporous materials with cubic symmetry

The structure of and synthesis conditions for an organic–inorganic hybrid mesoporous material, HMM-3, containing ethane fragments (–CH2CH2–) within the pore walls were studied. High resolution transmission electron microscope images and electron diffraction patterns obtained for different crystal axes of HMM-3 indicated that it was of the cubic Pm-3n space group, similar to mesoporous silica SBA-1. Scanning electron micrographs of HMM-3 in different directions confirmed that all of the produced HMM-3 particles had the crystal-like external morphology of a decaoctahedron (18-hedron) with six square {100} and 12 hexagon {110} planes with a cubic symmetry. The synthesis conditions for HMM-3 were optimized in a synthesis system comprising 1,2-bis(trimethoxysilyl)ethane (BTME), hexadecyltrimethylammonium chloride (C16TMA), sodium hydroxide (NaOH), and water (H2O). The highly ordered HMM-3 material was obtained at 95°C with the mixture ratio of BTME:C16TMA:NaOH:H2O=5.27:4.79:12:1773. The C16TMA/BTME ratio and C16TMA concentration affected the structural order of the produced mesophase. Only the cubic Pm-3n phase was formed even though the C16TMA/BTME ratio and the C16TMA concentration were varied with in wide ranges at 95°C.

New nanocomposites: putting organic function “inside” the channel walls of periodic mesoporous silica

Nature's accomplishments are inspiring chemists to design new materials based on biologically formed organic and inorganic structures that have been optimized over evolutionary timescales. A recent breakthrough in biomimetic materials chemistry has seen the fusion of organic and inorganic chemistry within the channel walls of periodic mesoporous organosilicas (PMOs). The incorporation of organic moieties in the walls of the liquid crystal templated mesoporous silica confers unique chemical, physical and mechanical properties upon the materials. In this Feature Article, we provide an overview of this new class of materials and propose a classification scheme that will distinguish the PMOs from other mesoporous organic–inorganic hybrid materials.

Study of the accessibility of phosphorus centres incorporated within ordered mesoporous organic–inorganic hybrid materials

Phosphorus centres incorporated within surfactant-directed mesoporous hybrid materials are shown to be more easily accessible than those incorporated within the corresponding materials prepared in the absence of surfactant.

Synthesis by neutral surfactant assembly of ordered mesoporous organic-inorganic hybrid materials incorporating phosphorus centres

The co-condensation of tetraethoxysilane (TEOS) and organotrialkoxysilane R'Si(OEt)3 (R' group containing a phosphorus atom) in the presence of a neutral surfactant (n-C16H33NH2) template provides ordered mesoporous hybrid materials. We show that further chemical reactions (sulfuration and quaternization) at phosphorus centres do not disrupt the ordered structure and the textural characteristics of the materials.