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

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