Mesoporous fiber

Fig. 6 TEM image of the fiber center of an ordered mesoporous fiber taken perpendicular to the fiber axis on a microtomed sample, from ref. [28].

Transparent mesoporous fibers with excellent order and parallel pores and doped by laser dye are prepared with good reliability. Influence of the nature of laser dye on the host - guest interaction is shown. Optical properties of Rhodamine 6G and Coumarine 120 embedded in mesoporous fiber waveguide have demonstrated utility for new laser materials, microphotonic devices or microreactors with increasing thermostability of dye component. The opportunity of preparation of the composite materieils mesoporous fiber / semiconductor is shown. 

Teng M, Wang H, Li F, Zhang B (2011) Thioether-functionalized mesoporous fiber membranes sol-gel combined electrospun fabrication and their applications for Hg2+ removal. J Colloid Interface Sci 355 23-28... 

Oya, A., Yoshida, S., Aleaniz-Monge, J. and Linares-Solano, A., Preparation and properties of an antibaeterial aetivated earbon fiber eontaining mesopores. Carbon, 1996, 34(1), 53 57. 

Fig. 15. Mesopore surface area as a function of pore diameter obtained from mercury intrusion data for PAN derived carbon fiber porous monoliths [28].

Detailed accounts of fibers and carbon-carbon composites can be found in several recently published books [1-5]. Here, details of novel carbon fibers and their composites are reported. The manufacture and applications of adsorbent carbon fibers are discussed in Chapter 3. Active carbon fibers are an attractive adsorbent because their small diameters (typically 6-20 pm) offer a kinetic advantage over granular activated carbons whose dimensions are typically 1-5 mm. Moreover, active carbon fibers contain a large volume of mesopores and micropores. Current and emerging applications of active carbon fibers are discussed. The manufacture, structure and properties of high performance fibers are reviewed in Chapter 4, whereas the manufacture and properties of vapor grown fibers and their composites are reported in Chapter 5. Low density (porous) carbon fiber composites have novel properties that make them uniquely suited for certain applications. The properties and applications of novel low density composites developed at Oak Ridge National Laboratory are reported in Chapter 6. 

Alternative support materials are being investigated to replace carbon black as support in order to provide higher corrosion resistance and surface area. These supports can be classified into (i) carbon nanotubes and fibers (ii) mesoporous carbon and (iii) multi-layer graphene and they are presented in detail in the following section. 

The Langmuir-Blodgett method has been used to prepare hybrid films of an anionic Ru(ll) cyanide polypyridyl complex with LDHs [170]. An LDH film was formed on mica owing to the interaction between LDHs particles and the Ru(ll) cyanide polypyridyl complex that was pre-dispersed on the surface of mica. Water-in-oU emulsions composed of octane, water and sodium dodecyl sulfate (SDS) have been used to synthesize Mg/Al LDHs with carbonate as the interlayer anion [171] by constant pH or variable pH methods. A floccule or fiber-like LDH material that possesses similar chemical composition and properties to that synthesized using a conventional variable pH method was obtained. The resulting LDH shows high surface area and a narrow distribution of mesopores. 

Porphyrin-based self-assembled molecular squares 389 can form mesoporous thin films in which the edge of a square, thus the size of the cavity, can be adjusted by appropriate choice of substituents [8]. Fibers that form coil-coiled aggregates with distinct, tunable helicity are built from crown ethers bearing porphyrins 390 [9]. In addition to the porphyrin applications discussed in Sections 6.3.2.2 and 6.4, dendrimer metalloporphyrins 391 to be applied in catalysis [10] and the water-soluble dendritic iron porphyrin 319 modelling globular heme proteins [11] can be mentioned. 

Figure 2. (A) SEM micrograph of the mesoporous silica ropes prepared by adding PEO-6000 into the CtgTMACl-HN03-TE0S-H20 mixture at 40 °C, PEO repeating unit/C18TMACl = 5.2 (B) a magnified cross-sectional view of the silica fiber.

Micro-mesoporous composite materials was prepared in a CEM microwave oven (MDS-2000) by using 50 - 100% of the maximum power of the oven (Wmax = 630 watts, frequency = 2.45 GHz, Pmax = 200 psi). The percentage power of microwave was programmed in percent increments to control the rate of heating. The fiber optic probe with a type of phosphor sensor was used for controlling the temperature of microwave oven. 

We have an excellent activated carbon of fiber morphology, so called activated carbon fiber ACF[3]. This ACF has considerably uniform slit-shaped micropores without mesopores, showing characteristic adsorption properties. The pore size distribution of ACF is very narrow compared with that of traditional granular activated carbon. Then, ACF has an aspect similar to the regular mesoporous silica in particular in carbon science. Consequently, we can understand more an unresolved problem such as adsorption of supercritical gas using ACF as an microporous adsorbent. 

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