• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1913-1916
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• 2013

• Transactions on Electrical and Electronic Materials
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• v.12 no.3
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• pp.119-122
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• 2011

A series of mesoporous silicalites was synthesized using different compositions of tetraethylorthosilicate and methyltriethoxysilane (MTES) as the silica source. Cetyltrimethylammonium bromide was used as the organic template. Their detailed pore structures were investigated by transmission electron microscopy, X-ray diffraction, and N2 adsorption method. The thermal properties of these silicalites were studied by thermogravimetric analysis. The increased amount of MTES destroyed mesoporous channels and reduced pore sizes from 3.4 nm to 2.8 nm in calcined silicalites. The calcined silicalite transformed completely into an amorphous state at 30% MTES loading. Methyl pending groups of MTES hindered the structural ordering of ≡Si-O- frameworks, resulting in an amorphous structure. This was caused by the insufficient formation of supramolecular assembly with the organic template. No capillary condensation step was found in MS 7/3 silicalite. The other capillary condensation steps shifted toward the lower relative pressure with increasing MTES content, indicating the reduction of pore sizes.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.777-782
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• 2008

Using ultrasonic-induced polymerization of pyrrole, mesoporous $TiO_2$ thin film with polypyrrole nanoparticles was prepared. Polypyrrole nanoparticles were ultrasonically synthesized in the mother solution of mesoporous $TiO_2$ before spin-coating. The polypyrrole particles were well dispersed in the solution. After spin-coating and calcinations process, the nanocomposite films have well-organized pore channels without pore-collapse, and polypyrrole nanoparticles are well dispersed in mesoporous $TiO_2$ matrix. The pore size and light absorbance of the mesoporous nanocomposite thin films were controlled by using different template materials, and by using different amount of pyrrole monomer, respectively.