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We demonstrate, for the first time, the application of ordered mesoporous carbons with large pore sizes prepared from the surfactant-templating approach in efficient disposal of wastewater containing bulky dye molecules. The adsorption amount for the bulky dye (methylthionine chloride, fuchsin basic, rhodamine B, brilliant yellow, methyl orange, or Sudan G) is almost twice that of the activated carbon in which mesopores contribute almost 100% to the total surface area and volume. The ordered mesoporous carbon adsorbent has a high adsorption rate (>99.9%) for low-concentration dyes, good performance in decoloration regardless of the dye nature, including basic, acidic, or azo dyes, and high stability after dye elution. To establish the relationship between the pore texture and adsorption properties, three kinds of ordered mesoporous carbons with different pore sizes, surface areas, and pore volumes have been synthesized by using phenolic resins as carbon sources and triblock copolymer as a structure-directing agent. The XRD, TEM, and N2sorption measurements reveal that all mesoporous carbonaceous materials have the highly ordered 2D hexagonal mesostructure, high surface areas (398−2580 m2/g), large pore volumes (0.51−2.16 cm3/g), and uniform pore sizes ranging from 4.5 to 6.4 nm. The adsorption capacities are compared and the pore occupation is estimated to understand the adsorption behaviors in the ordered mesopores with different diameters and models. The spatial effect of dye molecules is the determinative factor for the adsorption in ordered mesoporous carbons with various pore textural properties. The mesoporous carbon with an extremely high surface area (2580 m2/g), a large pore volume (2.16 cm3/g), and bimodal pores (6.4 and 1.7 nm) prepared from the silica−carbon composite shows the highest adsorption capacities for bulky basic dyes among the three ordered mesoporous carbons. [ABSTRACT FROM AUTHOR]

Ordered mesostructured LaF 3nanoarrays have been, for the first time, synthesized via a one-step nanocasting process using La(CF 3COO) 3as a precursor and mesoporous silica as a hard template. The characterization of SAXS and XRD patterns and TEM and SEM images shows that the LaF 3nanowire arrays have long-range regularity of hexagonal mesostructure ( p6 mm) and single-crystalline feature. N 2-sorption isotherms reveal that ordered mesoporous LaF 3products have high BET specific surface area (∼75 m 2/g), large pore volume (0.15 cm 3/g), and narrow pore-size distribution (the mean value of 4.3 nm). The upconversion fluorescence has been realized in the Yb 3+/Er 3+(red/green) and Yb 3+/Tm 3+(blue) codoped LaF 3nanoarrays by upconversion (UC) excitation in the near-infrared region. The UC emission population for 4F 9/2, 2H 11/2, 4S 3/2, and 2H 9/2levels in the Yb 3+/Er 3+codoped LaF 3nanowire array matrixes depends on Er 3+concentration, the excitation density, and the specific surface areas. [ABSTRACT FROM AUTHOR]

Supramolecular aggregateʼs self-assembling approach has derived diverse mesostructured inorganic solids. Recent progresses involve ordered mesoporous carbonaceous frameworks. This review paper summarizes the synthesis of ordered mesoporous polymers and carbons based on the supramolecular aggregates as templates. Block copolymers are mainly introduced here. Both the aggregates of block copolymers themselves and the assembling with thermosetting resins have the abilities to organize ordered mesostructures. The understanding of the synthesis is on the formation of supramolecular arrangement of molecules, templating, cross-linking, removal of templates, and carbonization. In addition, the morphological control and the functionalization of ordered mesoporous carbonaceous materials are briefly summarized. The attractive mesoporous carbonaceous materials offer great opportunities in catalysis, water purification, electrodes, adsorbents, gas storage, aero-space, etc. [ABSTRACT FROM AUTHOR]

Highly ordered mesoporous carbons have been synthesized from a direct triblock-copolymer-templating process of organic–organic self-assembly. The organic precursors are phenol, formaldehyde, and a functional monomer of p-fluorophenol, and the organic structure directing agent is triblock copolymer Pluronic F127. Characterization using X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman, Fourier transform infrared (FTIR), and nitrogen adsorption techniques reveals that the fluorinated carbons possess highly ordered mesostructures, high surface areas (693–998 m 2/g), large pore sizes (3.0–4.4 nm), large pore volumes (0.43–0.70 cm 3/g), and C–F covalent bonds after high-temperature carbonization at 900 °C. Various mesostructures such as 2D hexagonal and 3D body-centered cubic structures can be synthesized by simply tuning the ratios of p-fluorophenol/phenol or phenol/triblock copolymer. The fluorinated mesoporous carbon modified glassy carbon (GC) electrode exhibits higher electron transfer rate than both pure mesoporous carbon FDU-15 modified and bare GC electrodes. This result further indicates the fluorination of mesoporous carbons and the potential for fluorinated mesoporous carbons in electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

An atmosphere-assisted heating process was utilized to transform mesostructured SiC−C nanocomposites in situ into ordered mesoporous SiOC and SiCN ceramics with relatively small structural shrinkage. The mesostructured SiC−C nanocomposites were fabricated using commercially available polycarbosilane (PCS) as a ceramic precursor and mesoporous carbon CMK-3 as a hard template that itself was prepared by a nanocasting procedure from mesoporous silica SBA-15. Reactive gases including air and ammonia were employed to simultaneously incorporate O or N into SiC ceramics and oxidize or reduce the carbon template and excess carbon deposits. The procedure was carried out at 500 °C for 10 h and at 1000 °C for 10 h for air- and ammonia-assisted in situ transformations, respectively. SAXS, XRD, N2sorption, and TEM analyses revealed that the mesoporous SiOC and SiCN ceramics exhibit open, continuous frameworks similar to that of the primary template ordered mesoporous SBA-15. The ordered mesoporous SiOC and SiCN ceramics have high surface areas (200−400 m2g-1), large pore volumes (0.4−0.8 cm3g-1), and narrow pore size distributions (4.9−10.3 nm). The structural shrinkage from mesostructured SiC−C composites to mesoporous SiC-based ceramics decreased with increasing initial pyrolysis temperature for SiC−C nanocomposites owing to the improvement of structural rigidity. This shrinkage was found to be as low as 2.6% from mesostructured SiC−C pyrolysis at 1400 °C to mesoporous SiCN-1400 via ammonia-assisted in situ transformation. [ABSTRACT FROM AUTHOR]

A facile dual-templating approach is demonstrated to prepare hierarchically ordered macro-/mesoporous carbons. Monodispersed silica colloidal crystals are used as a hard template, amphiphilic triblock copolymer PEO−PPO−PEO as a soft template, and soluble resols as a carbon source. The procedure involves packing and aging of silica microspheres, evaporation-induced organic−organic assembly of mesostructures in the void of microspheres, thermosetting and carbonization of phenolic formaldehyde (PF), and removal of silica scaffolds by HF. The obtained porous carbons have a highly ordered face-centered cubic macrostructure with tunable pore sizes of 230−430 nm and interconnected windows with a size of 30−65 nm. The rigid silica hard templates can prevent the shrinkage of the mesostructure during the thermosetting and carbonization process, resulting in large cell parameters (∼18 nm) and pore sizes (∼11 nm). The bimodal porous carbon materials have large BET surface areas (up to 760 m2/g), large pore volumes (∼1.25 cm3/g), and partially graphitized frameworks. With the increase in the silica sphere diameter, the BET surface areas and the window sizes increase. The hierarchically ordered carbon structures show strong diffraction at wavelengths of 500−690 nm depending on the treatment used. [ABSTRACT FROM AUTHOR]