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Ceramic/self-assembled monolayer (SAM) bilayer coatings can provide adequate protection for silicon devices, or act as a multipurpose coating for other electronic applications, due to synergistic effects by forming a hybrid coating structure. The organic SAM layer acts as a “template” for the growth of the ceramic layer, while the ceramic layer can provide protection from environmental and mechanical impact. Low-temperature solution-based deposition techniques, namely, an in-situ solution method (biomimetic) and a hydrothermal method, have been employed in this study. Specifically, phosphonate-based (diethyl phosphatoethyl triethoxy silane) SAMs were used as a template to generate a zirconia ceramic layer at low temperatures. Other organic templates such as -SiCl3-, -OH-, -HSO3-, or -CH3-terminated SAMs were also examined. The reactions to grow the ceramic film were found to be pH sensitive. The ceramic and SAM coatings were characterized by a variety of analytical techniques. A pathway for the formation of the ceramic coating is also discussed.

ORGANISMS such as diatoms and radiolaria synthesize elaborate biomineral exoskeletons which display hierarchical structures patterned on length scales from less than a micrometre to millimetres. Synthetic materials chemistry, in contrast, has traditionally been able to achieve regular patterning only on microscopic (

IN the rapidly developing area of advanced zeolite materials science, the development of novel optical, electronic and magnetic materials1–5 requires the synthesis of large single crystals of a well defined habit. Crystals of a specified size and shape are needed to fabricate membranes and sensor devices6,7. Large crystals of zeol-ites and molecular sieves are essential for refining structures and elucidating the intrinsic absorption and diffusion properties of these materials8,9. Here we present a method for growing uniformly large and morphologically well defined single crystals of all-silica, aluminosilicate and aluminophosphate molecular sieves with dimensions in the size range 0.4—5.0 mm. Our synthetic method relies on the use of a non-aqueous solvent, a mineralizer, an optional organic templating species and reagent amounts of water. We have prepared both large-pore and small-pore materials of various framework composition and structure type.

Our research involves the solvothermal synthesis and characterization of new 3D open-framework and low dimensional inorganic materials. We focus on heavier group 14 elements to prepare structures that are analogous to aluminosilicate zeolites, but the main emphasis is to obtain cationic materials, a feat not possible with silicon oxides. We have successfully synthesized a series of novel compounds with Pb as building block: a cationic layered lead fluoride material (BING-5, Pb3F5NO3); a neutral, layered lead phenylphosphonate pyridine (BING-6); and a layered lead metamethylphenyl-phosphonate (BING-9). A molecular solid, tetrafluorodipyridine-germanium (BING-10) was also obtained. These structures are characterized by a variety of solid state techniques, including: powder X-Ray diffraction (PXRD), thermogravimetric analysis (TGA), UV-Vis spectroscopy and NMR. Our BING-5 material can exchange its interlayer NO3- for a variety of other anions. It is also stable to 450°C, which is far superior to organic resins that are still the standard for anion-exchange.

A variety of titania microstructures have been synthesized using a swollen polymer matrix of polydimethylsiloxane (PDMS). The shapes and structures grown to date include spheres, ‘bowls’, ‘nets’ and ‘brain coral’ matrices. The PDMS polymer network can be swollen by one of a variety of organic solvents. These solvents create internal voids or spaces within the PDMS, of particular volume. These spaces can then be filled with metal alkoxide liquid. The metal alkoxide is then polymerized to form metal oxides, in a shape templated by the swollen PDMS polymer. The resultant product is a composite of metal oxide within a polymer. Some of the shapes can be removed mechanically or chemically. Methods of characterization include scanning electron microscopy (SEM) and optical microscopy. Potential applications of the shaped titania include catalysts, fillers, capsules, and chemical separators. The synthesis and characterization of these compounds will be discussed.

We report the synthetic conditions, physical properties and potential applications of late group 14 metal (Sn) 0D, 1D, 2D and 3D extended materials. The structures are primarily neutral chain and anionic layered compounds. The latter are charge-balanced by ammonium cations, as in and BING-7 [Sn(C2O4)F-] [NH4+] and BING-8 [Sn(PO4H)F-] [NH4+]. The neutral layered compound and chain compounds BING-1 [Na4Sn4(C2O4)F6], BING-2 [KSn(C2O4)F] and BING-4 [Sn(C2O4)(C5H5N)] have also been synthesized solvothermally. Thermogravimetric analysis (TGA) under nitrogen and in-situ variable temperature X-ray diffraction show that the materials decompose in the 200°C to 300°C range to more stable phases. Nuclear magnetic resonance (NMR) was used to monitor the ion-exchange properties of some of the materials. The intercalation properties of these materials are still being investigated.