Mesoporous carbons with ordered channel structure (COU-1) have been successfully fabricated via a direct carbonization of an organic-organic nanocomposite.The discovery of nanostructured carbon materials such as fullerenes 1 and carbon nanotubes 2 has led to a considerable interest in the development of various carbonaceous materials. In particular, porous carbonaceous materials have been attracting much attention because of their high surface areas, large pore volumes, chemical inertness and high mechanical stability. Porous carbons show promise in the fields of hydrogen-storage, catalysis and electrochemistry. Many researchers have reported control of such pore structures through the template method, using various inorganic porous materials such as alumina membranes, 3 zeolites, 4-6 siliceous opals 7 and silica xerogels. 8 Recently, various types of ordered mesoporous carbons (OMCs) have been generated via a multistep synthetic procedure, in which ordered mesoporous silicas (OMSs) are employed as hard templates. [9][10][11][12][13][14][15] The most common synthetic route yielding OMCs involves preparation of OMS templates, impregnation of the OMS pores with carbon precursors, carbonization, and removal of the templates ( Fig. 1(A)). The removal of the OMS templates can be performed through a treatment with HF solution, converting the carbon into a porous form, while retaining the nanostructural features of the OMSs.In contrast, our novel OMC synthesis route, reported here, avoids the use of hard templates, and could thus reduce the number of preparation steps and the cost involved in producing these materials. Our strategy is to use an organic-organic interaction between a thermosetting polymer and a thermallydecomposable surfactant to form a periodic ordered nanocomposite. The thermosetting polymer is carbonized by heating under N 2 , after which process it remains as a carbonaceous pore wall ( Fig. 1(B)). Resorcinol/formaldehyde (RF) and triethyl orthoacetate (EOA) were used as the carbon co-precursors and triblock copolymer Pluronic F127 was used as a surfactant (Fig. 1(C)). The resultant materials are referred to as COU-1.In a typical synthesis, 0.661 g resorcinol was completely dissolved in a mixture composed of 1.74 g deionized water, 2.3 g ethanol and 0.06 ml hydrochloric acid (5 mol l 21 ). Then, 0.378 g Pluronic F127 was added to the resorcinol solution. After the complete dissolution of the Pluronic F127, 0.487 g of triethyl orthoacetate and 0.541 g of formaldehyde was added to the solution, and stirred at 30 uC for 20 min. The resultant solution was added dropwise to a silicon substrate spinning at 50 rpm, and then the substrate was spun up to 1000 rpm for 2 min. For polymerization of the resorcinol with formaldehyde, the asdeposited sample was heated at 90 uC for 5 h, in air. Then, the resultant brown deposit was carbonized under a nitrogen atmosphere at 400 uC for 3 h at a heating rate of 1 uC min 21 , followed by further carbonization at 600 and 800 uC for 3 h.{ Electronic supplementary informati...

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Nano-phase transition of an organic−inorganic nanocomposite under vapor infiltration of tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS) was found in mesoporous thin film preparation. The rearrangement into a hexagonal periodic structure implies high mobility of the surfactant−silicate composites in solid phase. The swelling of film thickness and d spacing was observed under vapor infiltration. The nano-phase transition under vapor infiltration contains two competitive processes:  (1) the penetration of TEOS or TMOS into the film and (2) the reaction of the silanol group. Film thickness and d spacing were controlled by changing synthetic temperature, silica sources (TEOS and TMOS), catalysts (HCl and NH3), and the thickness of surfactant films. The films prepared from vapor phase show superior characteristics, such as high structural stability and high resistance to water adsorption. 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.

A catalyst in the form of a capsule catalyst was prepared by coating HZSM5 membrane on a preshaped Co/SiO2 catalyst pellet. The capsule catalyst with HZSM5 membrane exhibited excellent selectivity for light hydrocarbon synthesis, especially for isoparaffin synthesis from syngas (CO + H2). 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.

We have created a high-density gas of interacting positronium (Ps) atoms by irradiating a thin film of nanoporous silica with intense positron bursts and measured the Ps lifetime using a new single-shot technique. When the positrons were compressed to 3:3 10 10 cm ÿ2 , the apparent intensity of the orthopositronium lifetime component was found to decrease by 33%. We believe this is due to a combination of spin exchange quenching and Ps 2 molecule formation associated with colliding pairs of oppositely polarized triplet positronium atoms. Our data imply an effective cross section for this process of 2:9 10 ÿ14 cm ÿ2 .

A capsule catalyst for isoparaffin synthesis based on Fischer-Tropsch reaction was designed by coating a H-ZSM-5 membrane onto the surface of the pre-shaped Co/SiO(2) pellet. Morphological and chemical analysis showed that the capsule catalyst had a core-shell structure. A compact, integral shell of H-ZSM-5 crystallized firmly on the Co/SiO(2) substrate without crack. Syngas passed through the zeolite membrane to reach the Co/SiO(2) catalyst to be converted, and all hydrocarbons formed with straight chain structure must enter the zeolite channels to undergo hydrocracking as well as isomerization in this tailor-made confined reaction environment. A narrow, anti-Anderson-Schultz-Flory law product distribution was observed on these capsule catalysts. Contrary to a mechanical mixture of H-ZSM-5 and Co/SiO(2), C(10+) hydrocarbons were suppressed completely on this novel capsule catalyst, and the selectivity of middle isoparaffins was considerably improved. The carbon number distribution of the products depended on the thickness of the zeolite membrane, and it was possible to selectively synthesize specified distillates, such as gasoline-range, or heavier hydrocarbons from syngas directly, by simply adjusting the thickness of the zeolite membrane of the capsule catalyst. This kind of capsule catalysts can be extended to various consecutive reaction systems as the shell and core components are independent catalysts for different reactions. At the same time, shape selectivity and space-confined effects can be expected for the reactant, intermediates and product of the sequential reactions.

We successfully designed Zn ion doped ZSM-5/silicalite-1 core-shell zeolite catalyst. On methanol to para-xylene (MTpX) over the core-shell catalyst, p-xylene yield was 40.7 C-mol% and para-selectivity (para-xylene selectivity in xylene isomers) was higher than 99 C-mol%, which substantially exceeds the other results reported in the literature.

The catalytic properties of SAPO-34 nanocrystals (crystal size: 75 nm) on methanol-to-olefins (MTO) and dimethylether-to-olefins (DTO) reactions were compared with those of SAPO-34 (crystal size: 800 nm). The SAPO-34 nanocrystals showed a longer catalyst lifetime in both the reactions than 800 nm-sized SAPO-34. The rate of catalyst deactivation of SAPO-34 was similar for both the MTO and DTO reactions indicating that the reaction of MeOH to DME and the diffusion of MeOH and DME into the SAPO-34 nanocrystals are fast and are not a rate limiting process. A possible reason for the long catalyst lifetime of the SAPO-34 nanocrystals is a short residence time in a crystal for the produced hydrocarbons because of a shorter diffusion length.