A new thioether functionalized organic-inorganic ordered mesoporous composite as a highly selective and capacious Hg2+ adsorbent was synthesized by one-step co-condensation of (1,4)-bis(triethoxysilyl)propane tetrasufide (BTESPTS, (CH3CH2O)3Si(CH2)3S-S-S-S(CH2)3Si(OCH2CH3)3) and tetraethoxysilane (TEOS), with tri-block copolymer poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) EO20PO70EO20 as template.

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is an optical photograph of three light-emitting pixels emitting green light. It is seen that the pixels are clearly separated by the cathode separator. The maximum efficiency of the device fabricated with the separator was 1.17 lm/W. This value compares with 1.28 lm/W for the device fabricated without the separator. The difference of less than 10 % is believed to be within experimental error.A technique has been presented that enables one to fabricate reversely tapered structures in one simple step. The physics investigated with a model system of a tapered parallelopiped would provide the bounds within which the technique would work in terms of aspect ratios and one contact angle. The results presented reveal that the technique works for such a tapered structure ranging in size from micrometer to millimeter. This EMOF technique has been successfully applied to the fabrication of cathode separators that are used for the cathode patterning of OLEDs. The ability to fabricate reversely tapered structures efficiently and cheaply should lead to applications in optics and MEMS. ExperimentalThe fabrication procedure of these separators is illustrated in Figure 1. The master was made with a commercially available negative photoresist. The exposure was controlled to impart differing amount of dose to the resist as a function of the layer thickness. The usual procedure of spin-coating, pre-baking, printing, developing, and drying was followed. Onto this master, PDMS (Sylgard 184, Dow Corning) was cast to obtain the PDMS mold. The PDMS mold was placed for molding the structure onto a substrate. A drop of a polymer solution is used in MIMIC for molding. After a sufficient amount of time had elapsed for the molding, the PDMS mold was removed, leaving the fabricated structure on the substrate.An organic light-emitting diode based on the EMOF technique was fabricated. A three-layer OLED consists of 4,4,-bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl (NPB) as the hole transport layer, (8-hydroxyquinolino)aluminum (Alq 3 ) as the emitting layer, each 50 nm thick, and LiF/Al as the cathode on an ITO glass (20 X/square, 75 nm ITO). Prior to the deposition of the organic layers, the substrate was cleaned by procedures described previously [11]. The cathode separators were fabricated using the EMOF technique, and the organic layers for the OLEDs were deposited by high vacuum (~10 ±6 torr) thermal evaporation. All organic materials used for OLEDs were purified by thermal gradient sublimation before use.

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The synthesis and study of mesoporous materials containing nanoparticles is a fast-developing area of nanoscience and nanotechnology. As the sizes of the particles are confined to the nanoscale, quantum-confinement phenomena are often found as a result of changes in both the density and the effective bandgap of the electronic energy level; the ratio of surface to bulk atoms also increases significantly.[1] Mesoporous materials containing metal nanoparticles, in particular, have received a great deal of attention owing to their potential applications in catalysis as well as in miniaturized electronic and optical devices.[2±4] Their location in the pores of porous materials results in their stabilization and modification of their properties. Thus, the synthesis and accurate control of the particle size is very important for these applications.Several approaches for the synthesis of mesoporous materials with nanoparticles located in the pores have been developed. The metals are introduced into the support either directly during the mesoporous silicate synthesis, or by postsynthesis treatment. Direct incorporation is performed by adding metal precursors to the synthesis silica gel before aging or by the stabilization of metal precursors inside the template micelles during the self-assembly of the surfactants and silica. Metal incorporation post-synthesis is carried out, using a calcined mesoporous support, by various routes, including incipient wetness impregnation, [5] ion exchange, [6] equilibrium adsorption, metal complex immobilization, [7±9] and vaporphase grafting.[10] However, the direct incorporation method has a relatively low metal-loading capacity, which limits its applications. A vapor-phase grafting method, such as chemical vapor deposition (CVD), is a very efficient method for preparing particles or thin films on a nanometer scale. However, the precursors are limited in terms of their high volatility and thermal stability. Other methods often yield the uncontrolled growth of metal particles both inside the pores and on the external support surface, resulting in a broad particle-size distribution, since during the reduction process, the metal particles can diffuse easily and therefore aggregate in the pores or on the outer surface of the host materials.[11] Accurate sizecontrol of nanoparticles using porous materials as hosts with a wide range of uniform pore sizes is therefore still a challenge. It has been demonstrated previously that Si±H can be used to reduce metal ions.[12] Recently, our group has succeeded in synthesizing mesoporous SBA-15 materials containing Pt nanoparticles by the substitution of the pore surface Si±OH groups with Si±Cl groups, followed by the reduction of Si±Cl to Si±H by LiAlH 4 . [13] Compared with other methods, this in situ reduction route allows efficient control of the growth of the metal particles. It is noticeable that previous reports on metal incorporation into mesoporous materials all concern isolated nanoparticles and nanowires, which may block the pore channels. H...

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