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Новости Nature

Nitrogen-doped mesoporous SiC materials with catalytically active cobalt nanoparticles for the efficient and selective hydrogenation of nitroarenes

Solid catalysts under the spotlight

A general soft-enveloping strategy in the templating synthesis of mesoporous metal nanostructures

Facile storage and release of white phosphorus and yellow arsenic

In situ quantitative single-molecule study of dynamic catalytic processes in nanoconfinement

Three-dimensional bicontinuous nanoporous materials by vapor phase dealloying

MXene molecular sieving membranes for highly efficient gas separation

Solid-state synthesis

Publisher Correction: Hierarchical self-entangled carbon nanotube tube networks

Three-Dimensional Bi-Continuous Nanoporous Gold/Nickel Foam Supported MnO2 for High Performance Supercapacitors

Ultrathin graphene oxide-based hollow fiber membranes with brush-like CO2-philic agent for highly efficient CO2 capture

Redox-switchable breathing behavior in tetrathiafulvalene-based metal–organic frameworks

Лента новостей (Journal of Porous Materials)

Correction to: Facile synthesis and capacitance properties of N-doped porous carbon/iron oxide composites through the single-step pyrolysis of coal-based polyaniline

Abstract

The original version of this article unfortunately contained the below equations in “Capacitance properties of NPC/FexOy composites” section which was not described, but was displayed in the article. The author wants to remove these equations.

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Magnetic carbon aerogel pyrolysis from sodium carboxymethyl cellulose/sodium montmorillonite composite aerogel for removal of organic contamination

Abstract

In this paper, we present a facile approach for the synthesis of polysaccharide-based carbon aerogel by sol–gel processing, freeze-drying, and pyrolysis of a sodium carboxymethyl cellulose/sodium montmorillonite composite aerogel. The as-prepared carbon aerogel was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffractometry, nitrogen adsorption measurements, and vibrating sample magnetometry. The carbon aerogel obtained in this study possessed low density (0.064 ± 0.0029 g/cm3), a high surface area (185 m2/g), and flame retardance. Measurements of the magnetic properties indicated that the carbon aerogel exhibited typical ferromagnetic characteristic at room temperature. The absorption capacity of the carbon aerogel for oils and organic solvents is as much as 10–20 times its own weight. Moreover, a method of combustion could be employed to recycle the carbon aerogel. The results imply that the carbon aerogel is a potential cost-effective adsorbent for oil and organic pollutants from aqueous solutions in environmental pollution cleanup.

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Constructing photocatalyst from β-Bi 2 O 3 photonic crystals for enhanced photocatalytic performance

Abstract

Photonic crystals with highly ordered structure have presented a prospective application in the design of photocatalysts. Herein, we fabricated visible-light active β-Bi2O3 photonic crystals via a modified sandwich infiltration method. By using the acetylacetone-complexed metal ion precursors, pure β-Bi2O3 photonic crystals with highly ordered structure could be obtained at a calcination temperature of 400 °C. Benefited from the facilitated mass transport in the highly ordered structure, β-Bi2O3 photonic crystals exhibited higher photocatalytic activity towards organic pollutions degradation than porous β-Bi2O3 and β-Bi2O3 nanocrystals. Furthermore, the photonic band gap of β-Bi2O3 photonic crystals could be modulated to overlap its electronic band gap by changing the macropore diameter into 220 nm. Slow photon effect could be observed over the β-Bi2O3 photonic crystals with a pore diameter of 220 nm, which enhanced the electronic band gap absorption and further improved the corresponding photocatalytic activity. The enhanced activity stability of β-Bi2O3 photonic crystals could also be observed. Based on the detection of active species, the degradation mechanism over β-Bi2O3 photonic crystals was discussed. The fabrication of β-Bi2O3 photonic crystals in this study provides experimental guidance for developing photonic crystals with enhanced visible light absorption and photocatalytic activities.

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Highly efficient removal of phenol from aqueous solutions using graphene oxide/Al 2 O 3 composite membrane

Abstract

To achieve superior separation performance in the phenol aqueous solutions treatment, a novel graphene oxide/Al2O3 composite membrane was prepared by a spin coating process. The microstructure measurement shows that the composite membrane has a multilayer structure and graphene oxide has been tightly coated on the surface of the Al2O3 membrane interlayer homogeneously. During the treatment of phenol aqueous solutions, the permeation flux and phenol rejection of the composite membrane were investigated. The results show the permeation flux of the membrane is about 1.153 L m−2 h−1 bar−1 and the phenol rejection of the membrane increases to 99.9% when the phenol concentration is 0.01 g L−1. The high phenol rejection of the composite membrane is mainly attributed to the physical sieving, the solution–diffusion effect and the hydrophobic nature of graphene oxide. All these results indicate the GO/Al2O3 composite membrane is a suitable material for the removal of phenol from aqueous solutions in environmental pollution management.

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Effect of porous properties on self-cooling of fired clay plate by evaporation of absorbed water

Abstract

Porous ceramic plates were prepared from clay and wood charcoal powder at 900 and 1100 °C and their porous properties, water absorption and the cooling effect of porous plates were investigated to produce eco-friendly porous ceramics for cooling by the evaporation of absorbed water. Porous properties were dependent on the firing temperature, and total pore volume, average pore size and porosity, which were 0.38–0.39 cm3/g, 0.15–0.17 μm and 49–50%, respectively at 900 °C and 0.31–0.33 cm3/g, 2.47–2.59 μm and 43–44%, respectively at 1100 °C. By the addition of wood charcoal powder, the cooling rate of porous plate fired at 1100 °C was 1.7 times faster than that of the plate fired at 900 °C and the cooling temperature difference (∆T) was around 2.3 °C at 22.5 °C and 52–54% of relative humidity and around 3.2 °C at 29 °C and 77–80% of relative humidity. The porous ceramic plates developed here are potential materials for cooling buildings.

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Tetraalkylammonium acetates and tetraalkylammonium tetrafluoroborates as new templates for room-temperature synthesis of mesoporous silica spheres

Abstract

Six surface active compounds containing: hexadecyltrimethylammonium [HDTMA], dodecyltrimethylammonium [DDTMA] or didecyldimethylammonium [DDA] cation and tetrafluoroborate [BF4] or acetate [OAc] anion were synthesized, purified and characterized, and subsequently applied for the synthesis of mesoporous silica materials of MCM-41 type. The materials were characterized using X-ray diffraction, Scanning Electron microscopy, and nitrogen physisorption method. Their structures were compared with that of reference MCM-41 material obtained with the conventional template [HDTMA][Br]. Nanosized silica spheres with size distribution in the range of 200–800 nm are obtained with the novel templates. The pore size of the obtained materials was in the range of 2.1–3.1 nm, and it was dependent only on the cation structure of the templates. The MCM-41 materials obtained with the acetate-based templates were characterized with a higher specific surface area in comparison with the reference material. On the basis of SEM, XRD and nitrogen physisorption data could be concluded that all tetraalkylammonium acetates used as templates lead to mesoporous silica nanospheres with very good textural characteristics, while in case of tetraalkylammonium tetrafluoroborates the best results in terms of particle uniformity and surface properties are obtained with [DDTMA][BF4]. MCM-41-[HDTMA][OAc] exhibited excellent loading capacity (374.1 mg/g) for the cyclic peptide antibiotic bacitracin, and moderate to good loading capacity for larger peptide and proteins such as insulin (70.3 mg/g) and lipase from porcine pancreas (70.8 mg/g).

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An efficient carbon catalyst supports with mesoporous graphene-like morphology

Abstract

In this work, we report the synthesis of ordered mesoporous carbon sheets (OMCS) with graphene-like morphology and their applications as the support for electrocatalysts. This lamellar material exhibits uniform mesoporous channels and ease of modification by using different nitrogen sources, such as melamine, urea, and ammonia. Nitrogen-doping on this material leads to a high specific surface area of 761 m2 g−1 and uniform pores with a diameter of 9 nm. Electrochemical tests show that the N-doped OMCS possesses high catalytic activities on the oxygen reduction reaction, which can be attributed to the pyridinic-type and pyrrolic-type nitrogen activating nearby carbon atoms. In addition, we demonstrate that the unique physical structure and surface chemical properties of OMCS improve the dispersion and structure of supported metal Ru nanoparticles, which lead to enhance oxygen evolution reaction activity.

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An erbium–organic framework as an adsorbent for the fast and selective adsorption of methylene blue from aqueous solutions

Abstract

The applicability of erbium–metal–organic framework (Er-MOF) in the adsorption and removal of methylene blue from aqueous solution has been studied. Er-MOF was synthesized by hydrothermal method and characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray powder diffraction. The high thermal stability, water stability and accessible nano-sized aperture for the Er-MOF could endow it with a very high potential in adsorption of dye pollutant. The adsorption isotherm, kinetic and thermodynamic investigations confirm that the adsorption behavior is based on Langmuir isotherm with an exothermic mechanism and enthalpy-driven process. The speed adsorption process (30 min), low cost, high efficiency, big surface area, selectivity and very high and rapid reusability are the main advantages of the proposed compound as a sorbent.

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