Zeolites are crystalline nanoporous aluminosilicates widely used in industry. In order for zeolites to find applications as innovative materials, they need to be organized into large two- and three-dimensional (2D and 3D) arrays. We report that uniformly aligned polyurethane films can serve as templates for the synthesis of uniformly aligned 2D and possibly 3D arrays of silicalite-1 crystals, in which the orientations of the crystals are controlled by the nature of the polymers. We propose that the supramolecularly organized organic-inorganic composites that consist of the hydrolyzed organic products and the seed crystals are responsible for this phenomenon.

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Image Formation: The film on the silicon wafer, prepared by the same method as for the fluorescence measurements, was covered with a photomask and irradiated with 254 nm UV light (8 J cm ±2 ). The irradiated film on the silicon wafer was dipped in a 5 mM fluorescamine solution and subsequently dried at 50 C for 4 h. The fluorescence image was observed by fluorescence microscopy.Quantum Yield Measurements: The relative quantum yields of the fluorescamine-treated copolymer solution and film were determined using a previously reported procedure [27]. The quantum yields of a Rhodamine B solution and a MEH-PPV film are 0.45 and 0.1, respectively [27,28]. Photoluminescence (PL) spectra were recorded using an ACTON spectrometer (SpectraPro-300i) connected to a photomultiplier tube (Acton Research, PD-438), with a xenon lamp as the excitation source that was connected to another monochromator One way of utilizing zeolite microcrystals for advanced materials is to organize them into ordered functional entities. [1] To this end, we have explored methods of organizing them in the form of closely packed and uniformly aligned monolayers on various substrates through large numbers of interconnecting molecular linkages between each microcrystal and the substrate.[2±14] The produced aligned monolayers of zeolite crystals can serve as useful seed crystals for the preparation of aligned continuous zeolite films that may find many useful applications. [15,16] So far, reflux and stirring' has been the only way to promote the reaction between functional groups tethered to the zeolite crystals and a substrate, to obtain monolayer assembly of the microcrystals on a substrate. Under these conditions, the typically required reaction time for achieving close to 100 % degree of coverage (DOC, defined as the percentage of the attached amount of crystals in the monolayer with respect to the maximum attached amount) of the substrate surface with the crystals is 24 h. Accordingly, it requires more than 24 h to achieve high degrees of lateral close packing (degree of close packing, DCP) between the crystals. We now report that ultrasound-aided strong agitation leads to a more than 10 3 -fold increase in the rate of achieving »100 % DOC and DCP. We discovered the above phenomenon during an investigation into the effect of the mode of reaction promotion (MRP) on DOC and DCP during the monolayer assembly of silicalite (SL) crystals on glass, by employing the previously reported method for the formation of covalent linkages between surface hydroxyl groups of bare zeolite crystals and 3-chloropro-COMMUNICATIONS

Glass plates tethered with 3-aminopropyl groups were prepared and fullerene (C60) was mounted onto the amine groups via NH insertion of the terminal amine moiety into one of the double bonds of fullerene. Cubic zeolite-A crystals covered with 3-aminopropyl groups on the external surface were independently prepared by treating the crystals with (3-aminopropyl)triethoxysilane. The zeolite-A crystals readily assembled in the form of monolayers on the fullerene-tethering glass substrates when they were allowed to contact in boiling toluene. The assembled zeolite-A monolayers remained intact even after sonication for 5 min in toluene. In contrast, the assembly of zeolite crystals does not occur if the tethering of either 3-aminopropyl or fullerene is omitted. Based on the two contrasting results, the monolayer assembly of zeolite crystals on glass is proposed to occur by formation of a large number of propylamine−fullerene−propylamine covalent linkages between each zeolite crystal and the glass substrate. Scanning electron microscope images revealed that zeolite-A crystals assemble with a face pointing normal to the plane of the substrate. The monolayers consist of small domains comprised of about 110 closely packed zeolite-A crystals aligned in uniform three-dimensional orientation. The same procedure also worked well for the monolayer assembly of larger ZSM-5 crystals. Migration of the weakly bound zeolite crystals over the glass substrate driven by a large number of hydrogen bonds between the surface-bound amine groups on the neighboring crystals is proposed to play an important role in inducing the close packing.

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