Rigid wiry nets: Conjugated microporous polymer networks are formed by Sonogashira–Hagihara coupling. Although these materials are amorphous, the micropore size and surface area can be controlled by varying the length of the phenyleneethynylene struts (see picture; the network is shown in blue, and one 1,3,5‐substituted benzene node and three connected struts are highlighted with C gray and H white).

A series of rigid microporous poly(aryleneethynylene) (PAE) networks was synthesized by Sonogashira-Hagihara coupling chemistry. PAEs with apparent Brunauer-Emmet-Teller surface areas of more than 1000 m(2)/g were produced. The materials were found to have very good chemical and thermal stability and retention of microporosity under a variety of conditions. It was shown that physical properties such as micropore size, surface area, and hydrogen uptake could be controlled in a "quantized" fashion by varying the monomer strut length, as for metal-organic and covalent organic frameworks, even though the networks were amorphous in nature. For the first time, it was demonstrated that these properties can also be fine-tuned in a continuous manner via statistical copolymerization of monomer struts with differing lengths. This provides an unprecedented degree of direct synthetic control over micropore properties in an organic network.

We report the largely improved electrochemical capacitance of polypyrrole-derived microporous carbon nanospheres (MCNs, 80-100 nm in diameter) containing nitrogen functional groups. We have investigated the electrochemical properties of precursor polypyrrole nanospheres (PNs, with a high N/ C ratio and low surface area) and as-derived carbon nanospheres (CNs, with a moderate N/C ratio and low surface area) prepared by carbonizing PNs at different temperatures, and MCNs (with a low N/C ratio and high surface area) obtained by chemical activation of CNs. The samples are thoroughly characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, thermogravimetric analysis (TGA), nitrogen sorption, elemental analysis, and X-ray photoelectron spectroscopy (XPS). It is found that MCNs with a high surface area and N-doping species exhibit much better capacitive performance compared to the PNs and CNs, and commercial carbon blacks (XC-72 and BP2000) as well. The MCN sample gives a reversible specific capacitance of $240 F g À1 for 3000 cycles in aqueous media as a result of combined advantages of high electrochemical activity of doped heteroatoms (N and O) and accessible well-developed porosity, demonstrating the promising use in high-energy-density supercapacitors.

Hierarchically ordered macro-mesoporous titania films have been produced through a confinement self-assembly method within the regular voids of a colloidal crystal with three-dimensional periodicity. Furthermore, graphene as an excellent electron-accepting and electron-transporting material has been incorporated into the hierarchically ordered macro-mesoporous titania frameworks by in situ reduction of graphene oxide added in the self-assembly system. Incorporation of interconnected macropores in mesoporous films improves the mass transport through the film, reduces the length of the mesopore channel, and increases the accessible surface area of the thin film, whereas the introduction of graphene effectively suppresses the charge recombination. Therefore, the significant enhancement of photocatalytic activity for degrading the methyl blue has been achieved. The apparent rate constants for macro-mesoporous titania films without and with graphene are up to 0.045 and 0.071 min(-1), respectively, almost 11 and 17 times higher than that for pure mesoporous titania films (0.0041 min(-1)).

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Hollow spheres with nanometer-to-micrometer dimensions, controlled internal structure, and shell composition have attracted tremendous attention because of their potential application in catalysis, drug delivery, nanoreactors, energy conversion and storage systems, photonic devices, chemical sensors, and biotechnology.[1] Single-shell and double-shell hollow spheres of various compositions have been synthesized by a number of methods, such as vesicles, emulsions, micelles, gas-bubble, and hard-templating methods.[2] More recently, efforts have focused on the fabrication of hollow spheres with multiple shells, as these materials are expected to have better properties for applications such as drug release with prolonged release time, heterogeneous catalysis, lithiumion batteries, and photocatalysis.[3] For example, multipleshell hollow microspheres of Cu 2 O have been prepared by vesicle templating and an intermediate-templating phasetransformation process. [3a,b] Multiple-shell azithromycin hollow microspheres were fabricated by hierarchical assembly.[3c] Cao and co-workers reported the synthesis of tripleshelled SnO 2 hollow microspheres by chemically induced selfassembly in the hydrothermal environment which exhibited enhanced electrochemical performance.[3d] Yao and co-workers reported excellent cycle performance and enhanced lithium storage capacity of multiple-shell Co 3 O 4 hollow microspheres synthesized by oriented self-assembly.[4] These preparative methods, however, are suited for each specific material and cannot be applied generally to a wide range of materials. Currently, there is no general synthetic approach for fabricating multiple-shell hollow nanostructures of any desired material.Herein, we present a straightforward and general strategy to prepare metal oxide hollow microspheres with a controlled number of shells. Carbonaceous microspheres were used as sacrificial templates. The microspheres were saturated with a desired metal salt solution and then heated in air; the carbonaceous template evaporates and templates the formation of metal oxide shells. The number of shells is controlled by the metal ion loading and the process is general for a wide range of metal oxide materials.Scheme 1 illustrates the general process of fabricating multiple-shell hollow metal oxide microspheres. The key to this process is the use of carbonaceous particles rich with surface functional groups available for metal ion adsorption. [5] Multiple shells are generated by supplying enough shell precursor material to the sacrificial carbonaceous spheres. Recently, our group reported the synthesis of hollow coreshell ferrite microspheres, [5b] demonstrating that carbonaceous particles can absorb a significant amount of metal ions within the interior of the particle ( Figure S1 in the Supporting Information). In this work, we extend these methods and demonstrate the general and facile synthesis of multiple-shell hollow microspheres of a wide range of different metal oxides.Figure 1 a,b shows a transmission electron micro...

This review summarizes the recent progress in methanation catalysts for SNG production, which will provide insights for future catalysts design.

High surface area porous poly(phenylene butadiynylene) networks were obtained (BET surface area up to 842 m(2) g(-1)) by the palladium-catalyzed homocoupling of 1,3,5-triethynylbenzene and 1,4-diethynylbenzene.