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International audience; A new approach for the synthesis of supported zeolite Y membranes is presented, using a synthesis gel containing seeds to avoid any unnecessary ex situ pre-treatment of the support.

Using a sol–gel/spin-coating method, transparent mesoporous silica thin films containing single-site photocatalyst (Ti, V, Cr, Mo, and W oxide moieties) (Me-MSTFs) could be prepared on quartz plate...

Preparation method was established to synthesize a defect-free FER membrane by a vapor-phase transport (VPT) method. In preparing FER membrane a porous alumina support was dipped in a gel to coat with the gel. After drying, the gel on the alumina support was crystallized to FER under vapors of ethylenediamine, triethylamine and water. Two types of dipping methods were examined. First, the porous alumina support was dipped in a gel for 1 day. In the second method, after dipping the support in the gel for 1 day we forced the gel to penetrate into the pores of the alumina support by evacuating the support from one side. A permeation test of 1,3,5-triisopropylbenzene (TIPB) through FER membrane was carried out at room temperature to check the compactness of the FER membrane. The permeation of 1,3,5-triisopropylbenzene (TIPB) through FER membrane synthesized using the second dipping method was not detected, indicating that in the FER membrane there was no pinhole as large as the molecular dimension of TIPB. The pervaporation tests for cyclohexane, benzene, p-xylene and o-xylene were carried out at room temperature. The separation factor for a benzene/p-xylene mixture using the FER membrane was 100, which was much greater than 10.3 predicted from the gas-liquid equilibrium. The FER membrane showed a promising potential to separate organic compounds such as aromatic hydrocarbons.

Hexagonally arranged surfactant–catalyst composites were treated only with tetraethoxysilane vapor, resulting in the formation of the silica mesostructures without phase transition.

A catalyst in the form of capsule catalyst was prepared by coating HZSM5 membrane on a preshaped Co/SiO 2 catalyst pellet. The capsule catalyst with HZSM5 membrane exhibited excellent selectivity for light hydrocarbon synthesis, especially for isoparaffin synthesis from syngas (CO + H 2 ). Long chain hydrocarbon formation was totally suppressed by the zeolite membrane. The modification of membrane and core catalyst significantly improved the catalytic properties of these new kinds of capsule catalysts.

Ultrathin silica films with a monolayer of uniform nanopores were fabricated on a silicon substrate by contacting triblock copolymer films with tetraethoxysilane vapor followed by calcination to remove the copolymer.

The synthesis method to obtain a tight and thin zeolitic membrane was investigated. It was found that the most important factor to prepare a zeolitic membrane in a compact form was the pH to prepare the parent aluminosilicate gel. The aluminosilicate gel was supported on a porous alumina plate and treated in the vapor of templating reagents. It was found that a thin layer of ferrierite was formed on the surface of the plate. The rates of permeation of H 2 , He, CH 4 , O 2 , N 2 and CO 2 through the ferrierite membrane were measured. Permeation results indicated that the ferrierite membrane is formed in a compact form.

Ultrathin carbon films with a monolayer of uniform mesopores were synthesized on a silicon substrate by contacting triblock copolymer films with benzyl alcohol vapor followed by carbonization.

Mesoporous silica/phosphate composite films were synthesized from a vapor phase onto a Si substrate. Field emission scanning emission microscope and X-ray diffraction measurements show that the resultant films have ordered pore channels with a hexagonal arrangement parallel to the film surface. The proton conductivity for the mesoporous silica/phosphate composite films was 0.07-0.38 S cm -1 . The proton conductivity was not affected much by water vapor pressure. The activation energy for the proton conduction was low (13 kJ mol -1 ). The high P-OH group content and the ordered periodic mesostructure contributed to the high proton conductivity.

A mesoporous MCM-48 membrane with high thermal stability has been synthesized on a porous stainless steel support by hydrothermal treatment.

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A defect-free MOR membrane is synthesized on a porous alumina plate by a vapour phase transport method: shape selectivity is apparent in the pervaporation of a benzene–p-xylene mixture (the separation factor exceeded 160).

A thin zeolitic membrane on porous alumina support has been synthesized; the permeability of the film to N2 and O2 indicated that the membrane was formed in a compact form.

Low-k dielectric materials have been in demand in order to solve the physical limits of interconnects for a new LSI technology system. Ordered mesoporous silica films are promising materials as low-k dielectrics because of their high porosity and high mechanical strength. Here, we show two preparation methods for thermally stable mesoporous silica films.First, a mesoporous silica film was prepared on a silicon substrate using a spin-coating process followed by a vapor treatment using tetraethyl orthosilicate (TEOS). The TEOS-treated mesostructured silica film did not contract during calcination, showing high structural stability. A flat mesoporous silica film about 250 nm thick was grown from the silicon substrate. No silica particle was deposited on the surface of film. FTIR studies suggested that the Si-OH groups in the film significantly decreased after the TEOS treatment. TEOS molecules penetrate into an originally deposited silicate film and react with the silanol groups. The densified silica wall has high structural stability and hardly contracts under a calcination process.Vapor-phase synthesis is another promising method for the preparation of thermally stable mesoporous silica film. We found nano-phase transition of an organic-inorganic nanocomposite under vapor infiltration of TEOS. The rearrangement into a hexagonal periodic structure implies high mobility of the surfactant-silicate composites in solid phase. The vapor infiltration method is a simpler process than conventional sol-gel techniques and attractive for mass production of a variety of organic-inorganic composite materials and inorganic porous films.