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The movement of the sulfur species of a lithium – sulfur battery cathode was directly observed through pioneering operando SAXS analysis. Micropore is a prior repository for sulfur before and after the electrochemical reaction. Mesopore is actual reaction site for sulfur species. The separate properties of the pores were established, adding critical insight to advanced carbon cathode material design. [ABSTRACT FROM AUTHOR]

An open-tubular radially cyclical electric field-flow fractionation technique which achieves the online separation of microparticles in a functional annular channel is proposed in this study. The system was set up by using a stainless steel tube and a platinum wire modified with ionic liquid/mesoporous silica materials as the external and internal electrodes. The feasibility for online separation of various particles was experimentally demonstrated. Particles in the channel were affected by a radial electric field and field-flow fractionation (FFF). On the cross section, different particles showed distinctive migration distances depending on their own properties and the different magnitudes of forces being exerted. The same kind of particles form an annular distribution within the same annulus while different particles form annular distributions at varied concentric annuli through electrophoresis. Under a laminar flow of FFF, different sizes of particles formed a conical arrangement within the annular separation channel. With the joint influence of electric field and flow field, different trajectories were obtained and the particles were eventually separated. Voltage, frequency and duty cycle value are the main parameters affecting the separation of particles. By adjusting these parameters, particles migrate in a zigzag trajectory on one side of the electrodes (mode I) and reach both sides of the electrodes (mode II). Six polystyrene particles were completely separated with high resolution within several minutes. Our system offers numerous advantages of label-free, high-resolution and online separation without tedious operations, and it is a promising tool for the effective separation of various micro-objects. [ABSTRACT FROM AUTHOR]

Organic electrode materials are promising for electrochemical energy storage devices because they have a high theoretical capacity, structural diversity, and flexibility. In addition, they are light weight, inexpensive, and environmentally benign. Organic electrode materials are a promising alternative to conventional inorganic materials. Various organic materials, such as conducting polymers, organodisulfides, nitroxyl radical polymers, and conjugated carbonyl compounds, have been studied as electrode materials for lithium batteries. Among them, small organic carbonyl compounds and polymers containing carbonyls have been widely studied as electrode materials because of their high theoretical capacity, fast redox kinetics, and structural diversity. However, these materials have intrinsic drawbacks, such as solubility in electrolyte media and a low conductivity. Herein, methods to solve these problems by increasing the polarity are discussed. The polarity of small molecules could be increased by forming salts. In addition, the conductivity could be enhanced using a chemical doping strategy or forming a composite with a conductive additive. This review provides guidance for the design of a new type of organic material for next-generation rechargeable batteries. [ABSTRACT FROM AUTHOR]

Strong adsorption of phenolics on zeolite acid sites causes high trapping inside zeolite channels and low catalytic activity of zeolite-supported catalysts in atmospheric pressure hydrodeoxygenation (HDO) of lignin-derived phenolics. This adsorption is more severe at low temperatures, and restricts the atmospheric HDO of phenolics to high reaction temperatures. The purpose of this research was to develop a catalyst with low phenolic trapping potential and high HDO efficiency under mild reaction conditions. Among the tested catalysts (Fe/HBeta, FeReOx/HBeta, Fe/MCM-41, ReOx/MCM-41, FeReOx/MCM-41, Fe/ZrO2 and FeReOx/ZrO2), the novel catalyst of FeReOx/ZrO2 exhibited the highest catalytic efficiency for mild-condition (pressure: 1 atm and temperature ＜350 °C) HDO of phenolics (guaiacol, m-cresol and anisole), and led to the selective production of BTX aromatics. Compared to Fe/HBeta(38) as a zeolite-supported catalyst, FeReOx/ZrO2 displayed remarkably enhanced performance, and its catalytic activity for the HDO of m-cresol at 350 °C was almost twice higher than that of Fe/HBeta(38) at 500 °C. Importantly, FeReOx/ZrO2 revealed a high HDO efficiency (BTX yield of 50.5 wt% with phenolic trapping below 5 wt%) at a low temperature of 250 °C, while Fe/HBeta(38) almost lost its entire catalytic activity at this temperature, and gave a low BTX yield of 3.0 wt% with a high trapped phenolic yield of 83.1 wt%. The remarkable catalytic activity of FeReOx/ZrO2 in the HDO of phenolics at atmospheric pressure and temperatures as low as 250 °C is a result of its mesoporosity and oxophilicity as well as its well-balanced acidity induced by both rhenium oxide and zirconia support causing a high dehydration efficiency. [ABSTRACT FROM AUTHOR]

Highly ordered mesoporous compound semiconductors (CdxZn1−xSe) with crystalline frameworks were successfully synthesized via a nano-replication method from a mesoporous silica template (bicontinuous 3D cubic Ia3d mesostructure, KIT-6). Simple impregnation with various molar compositions of the precursors within mesopores of the silica template, reduction at 500 °C under hydrogen atmospheres and subsequent removal of the silica template using NaOH solution resulted in the mesoporous CdxZn1−xSe ternary compound semiconductor. The mesoporous CdxZn1−xSe materials with high surface areas (90–120 m2 g−1) were investigated by X-ray diffraction, N2 adsorption–desorption, electron microscopy, and UV-visible spectroscopy. The unique optical properties and band gap profiles of the template-free CdxZn1−xSe materials were controlled chemically by different Cd/Zn molar compositions, and also physically by the framework thickness. Diffuse reflectance UV-visible studies indicate that the band gap energies (Eg) of the mesoporous CdxZn1−xSe materials widened as the amount of Cd decreased. Decreasing the framework thickness also results in the band gap widening of the mesoporous Cd0.5Zn0.5Se materials due to the nano-size effect. [ABSTRACT FROM AUTHOR]

Highly ordered mesoporous SnO2materials with residual silica species were successfully synthesized from a mesoporous silica template (SBA-15) vianano-replication and simple etching processes. A tin precursor, SnCl2·2H2O, was infiltrated spontaneously within the mesopores of the silica templates by melting the precursor at 353 K without using a solvent. After the heat-treatment of composite materials at 973 K under static air conditions, the controlled removal of silica templates using NaOH or HF solutions with different concentrations results in the successful preparation of mesoporous SnO2materials, where the amounts of residual silica species are in the range 0.9–17.4 wt%. The residual silica species induce a nano-propping effect enabling the mesoporous SnO2material (containing 6.0 wt% of silica species) to remain stable up to 973 K without any significant structural collapse. More importantly, the optimum amount of residual silica species (3.9–6.0 wt%) results in a dramatic reduction in capacity fading after prolonged charging–discharging cycles in Li-ion battery. The mesoporous SnO2material with 3.9 wt% of silica species still exhibits a large capacity (about 600 mAh g−1) after the 30thcycle, which is probably because the residual silica species act as a physical barrier to suppress the aggregation of Sn clusters formed in the mesoporous SnO2materials during the reversible lithium storage. [ABSTRACT FROM AUTHOR]

Sulfur-containing ordered mesoporous carbon (S-OMC) material was successfully obtained from a mesoporous silica template through a nano-replication method using p-toluenesulfonic acid as the framework source. The S-OMC material thus obtained could be utilized as an excellent support for Pt nanoparticles of size 3.14 nm, even though the Pt loading was 60 wt%. The Pt nanoparticles supported on the S-OMC material (Pt/S-OMC) exhibited excellent thermal stability compared with those supported on sulfur-free ordered mesoporous carbon and Vulcan carbon. XPS analysis indicated that the strong metal-support interaction between the sulfur atoms in the S-OMC support and the surface atoms of the loaded Pt nanoparticles played an important role in stabilization of the Pt nanoparticles against the Ostwald ripening process during the thermal treatments. Cyclic voltammogram results revealed that the Pt/S-OMC material exhibited reasonably high electrochemically active Pt surface areas before and after thermal treatments at 600 °C, indicating that the surface of Pt nanoparticles was not poisoned by the sulfur atoms of the S-OMC support. [ABSTRACT FROM AUTHOR]

A novel method that selectively polymerizes pyrrole on the silica surface without inducing polymerization in bulk solution is developed, which is based on in situgeneration of the NO+ion as an oxidant at the silica surface. [ABSTRACT FROM AUTHOR]

A novel method that selectively polymerizes pyrrole on the silica surface without inducing polymerization in bulk solution is developed, which is based on in situgeneration of the NO+ion as an oxidant at the silica surface. [ABSTRACT FROM AUTHOR]

The oxidative desulfurization (ODS) of organic sulfur compounds over tungsten oxide supported on highly ordered mesoporous SnO 2 (WO x /meso-SnO 2 ) was investigated. A series of WO x /meso-SnO 2 with WO x contents from 10 wt% to 30 wt%, were prepared by conventional wet impregnation. The physico-chemical properties of the WO x /meso-SnO 2 catalysts were characterized by X-ray diffraction (XRD), N 2 adsorption-desorption isotherms, electron microscopy, Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and the temperature-programmed reduction of hydrogen (H 2 -TPR). The characterization results indicated that these catalysts possessed mesoporous structures with uniform pores, high specific surface areas, and well-dispersed polyoxotungstate species on the surface of meso-SnO 2 support. The ODS performances were evaluated in a biphasic system (model oil/acetonitrile, S initial = 2000 ppm), using H 2 O 2 as an oxidant, and acetonitrile as an extractant. Dibenzothiophene (DBT) in the model oil was removed completely within 60 min at 50 °C using 20 wt% WO x /meso-SnO 2 catalyst. Additionally, the effect of reaction temperature, H 2 O 2 /DBT molar ratio, amount of catalyst and different sulfur-containing substrates on the catalytic performances were also investigated in detail. More importantly, the 20 wt% WO x /meso-SnO 2 catalyst exhibited 100% surfur-removal efficiency without any regeneration process, even after six times recycling., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A novel method that selectively polymerizes pyrrole on the silica surface without inducing polymerization in bulk solution is developed, which is based on in situ generation of the NO(+) ion as an oxidant at the silica surface.

Highly ordered mesoporous silver, which exhibits well-defined mesopores, high surface area and pore volume, has been successfully obtained using a cubic mesoporous silica, KIT-6, with controlled surface hydrophobicity as the hard template.

Combining both nano-replication and nano-imprinting techniques using dual silica templates provides a simple way to synthesize ordered mesoporous carbons with bimodal pore size distributions ( approximately 1.5 nm and approximately 3.5 nm).

The silylation of SBA-15 enhances the reducibility of cobalt oxides on a SBA-15 supported cobalt catalyst, and consequently increases the catalytic activity for Fischer-Tropsch synthesis of hydrocarbons from syngas and selectivity for longer chain products.

Highly ordered mesoporous materials constructed with integrated polymer-silica hybrid frameworks can be obtained via a one-step synthetic strategy using a mixture of polymer and silicate as the framework sources in the presence of a structure-directing agent.

Highly ordered mesoporous silica can be regenerated from a mesoporous carbon CMK-3 that is a negative replica of mesoporous silica SBA-15, indicating reversible replication between carbon and inorganic materials.