Spheroidal ordered mesoporous carbon materials with diameter of 2–10 μm were synthesized by direct carbonization of silica/triblock copolymer P123/butanol composites using P123 and butanol as the structure-directing agents and carbon precursors. The morphologies, structures and pore characteristics of the carbon materials were investigated by scanning and transmission electron microscopes, X-ray diffraction, and nitrogen sorption. It was found that the material possesses a cubic ordered mesoporous structure with Ia3d symmetry. The butanol addition directly affects the carbon morphology and pore structure. When the mass ratio of butanol to P123 is 0.5:1, the product exhibits a perfectly spheroidal morphology with a specific surface area of 1236 m2 g−1 and a total pore volume of 1.26 cm3 g−1. The formation mechanism of the spheroidal ordered mesoporous carbon materials is discussed briefly. 相似文献
Sandwich-type ordered mesoporous carbon/graphene nanocomposites were successfully synthesized using 2D ordered mesoporous silica/graphene nanocomposites as the hard template and an ionic liquid as a N-rich carbon source. We used an ionic liquid of 1-(3-cyanopropyl)-3-methylimidazolium dicyanamide containing nitrile groups (–CN) in the cation and anion as a carbon precursor for the preparation of the nanocomposites. Nitriles do not decompose under thermal treatment in an inert gas atmosphere, but leave significant amounts of N-rich carbon materials. The nanocomposites had a large surface area (1,316 m2·g–1), an average pore diameter of 5.9 nm, and high electrical conductivity. The nanocomposite electrode showed a high specific capacitance of 190 F·g–1 at 0.5 A·g–1 in 1 M TEABF4/AN electrolyte and a good rate capability between 0 and 2.7 V for supercapacitor (or ultracapacitor) applications.
Mesoporous silica nanospheres (MSNs) with regular pores have been fabricated using cetyltrimethylammonium bromide (CTAB) as surfactant in high pH solution. The average size of the MCM-41 silica nanospheres was reduced from 95 to 48€nm, while the concentration of CTAB increases from 7.7 to 11.5mmol/L. Carbon black was deposited on MSNs using hexane as the carbon source. By mixing such materials with silicone rubber, the composites become conducting when equivalent carbon volume fraction is higher than a certain region, which is less sensitive to the morphology of the deposited carbon. The improved piezoresistance repeatability has been found on the composite sample of MSNs/carbon plus extra high conducting carbon black. The load and strain sensitive range up to 0.35MPa and 0.10, respectively, with less resistance fluctuation during multiple press loading cycles. 相似文献
Hollow mesoporous carbon spheres (HMCSs) have been prepared by a simplified replication route from a solid silica core/mesoporous silica shell aluminosilicate (SCMS-Al) template, which was synthesized by directly incorporating aluminum species into the mesoporous framework during template synthesis. The size of HMCSs can be tuned between 80 and 470 nm by simply changing the diameters of SCMS-Al. The HMCSs have uniform mesopores with a narrow pore size distribution (3.4-4.1 nm), and high surface area, (890-1150 m2/g) and total pore volumes (0.75-1.15 cm3/g). The techniques of N2 sorption isotherms, TEM, EDX and SEM were used to characterize the as-synthesized spheres. 相似文献
The polyaniline composition by silica based mesoporous hollow nanosphere (silica-HNS) was synthesized and selected as a promising solid support for palladium nanoparticle stabilization. Then the nanocomposite was applied as a nanocatalyst for aerobic benzyl alcohol oxidation reactions. Catalyst recyclability showed six successful runs for the reaction. TEM and SEM-EDX/mapping images were used to study the structure and morphology of the PdNPs@PANI/HNS. FT-IR spectroscopy, Thermal gravimetric analysis (TGA), and BET were used to characterize and investigate the catalyst nature. In addition, the amounts of Pd loading were characterized by ICP-AES technique. 相似文献
