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Reduction of the anthropogenic emission of CO 2 is currently a top priority because CO 2 emission is closely associated with climate change. Carbon capture and storage (CCS) [1] and the development of renewable and clean energy sources are two approaches for the reduction of CO 2 emission. One of the most promising alternative fuels is CH 4 , which is the major component of natural gas. The efficient storage of CH 4 is still one of the main challenges for its widespread application. Accordingly, the development of more efficient approaches for CO 2 capture and CH 4 storage is critically important.Recently, metal-organic frameworks (MOFs, e.g., MOF-210 and NU-100) [2] have shown great potential for gas storage because of their high specific surface area (SSA) and functionalized pore walls. However, most MOF materials still show relatively low CO 2 and CH 4 uptakes. To enhance CO 2 and CH 4 adsorption, it is imperative to develop new materials, such as covalent organic frameworks (COFs), [3] or to modify MOFs by using postsynthetic approaches. [2b, 4] Herein, we focus on the latter strategy. One of the modification approaches is incorporation of carbon nanotubes (CNTs) into MOFs in order to achieve enhanced composite performance, because of the unusual mechanical and hydrophobicity properties of CNTs.[5] Another approach is doping MOFs or COFs with electropositive metals.Recent studies indicate that the surface carboxylate functional groups of a substrate could act as nucleation sites to form MOFs by heterogeneous nucleation and crystal growth.[6] Both experimental and theoretical investigations indicate that the H 2 adsorption capacities of MOFs can be enhanced significantly by doping alkali-metal ions, in particular Li + ions, to the frameworks, owing to the strong affinity of Li + ions towards H 2 molecules. [3d, 7] Similarly, Lan et al. also showed theoretically that doping of COFs with Li + ions can significantly enhance the CH 4 uptake of COFs.[8] Most recently, the multiscale simulations performed by Lan et al. indicate that Li is the best surface modifier of COFs for CO 2 capture among a series of metals (Li, Na, K, Be, Mg Ca, Sc and Ti).[9] Furthermore, their simulations show that the excess CO 2 uptakes of the lithium-doped COFs can be enhanced by four to eight times compared to the undoped COFs at 298 K and 1 bar. [9] Motivated by these experimental and theoretical results, we synthesized hybrid MOF materials by using the two modification techniques outlined above, that is, 1) incorporation of CNTs into [Cu 3 (C 9 sites that become available for interaction with other molecules after removal of H 2 O in from Cu 2+ carbonyl complexes, and can also be easily rehydrated without change of the crystalline nature of the material after exposure to air [11] (see Figure S1 in the Supporting Information). Although the btc ligand can not act as an electron receptor for the electron transfer from the naphthalenide radical anion, [7c] the rehydration of the Cu 2+ sites in the framework makes the electron trans...

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Recent experiment and simulation show that introduction of lithium in the frameworks can enhance the gasstorage capacities of framework materials. Here a covalentorganic polymer-1 (COP-1) has been synthesized through the self-polymerization of monomer 1,3,5-tris((4-bromophenyl)ethynyl) benzene (TBEB) by the nickel(0)-catalyzed Yamomoto reaction. To enhance gas adsorption properties of the COP-1 material, we have proposed a novel lithium-decorating approach in which the alkynyl functionalities in COP-1 are postsynthetically converted to lithium carboxylate groups with the aid of dry ultrapure CO 2 . In particular, the H 2 uptake of lithium-modified COP material is 1.67 wt % at T = 77 K and ∼1 bar, which is increased by ∼70.4%, compared with the unmodified compounds. Besides, the enhancement effects of lithium modification on CO 2 and CH 4 adsorption have also been observed. It is expected that this approach proposed here would provide a new direction for lithium modification of MOFs and COFs for clean energy and environmental applications.

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The impacts of the interfacial interaction modes and their strength on the filler dispersion and composites performances were clearly clarified.

This paper describes a controllable vesicle formation of a diblock copolymer of poly(ethylene oxide)-block-polybutadiene (PEO-b-PB) and a homopolymer of poly(acrylic acid) (PAA) in a solvent mixture of THF and n-dodecane. The number-average molecular weights (M n ) of both the PEO and PB blocks are 5100 g/mol; the weight-average molecular weight (M w ) of the PAA is ∼2000 g/mol. The assembly is driven by the hydrogen-bonding complexation between the complementary binding sites on PEO and PAA. The vesicles can load PAA far above the stoichiometrical monomer ratio of PAA to PEO ([AA]/[EO]). At 0.85 e [AA]/[EO] e 2.5, unilamellar vesicles (ULVs) with a constant membrane thickness of 16 nm are obtained in a controllable manner, of which the surface area increases linearly with [AA]/[EO]. Further increasing [AA]/[EO] above 3 results in the formation of multivesicular vesicles (MVVs). The PAA chains in ULVs are uniformly inserted into membranes with a direction preferentially perpendicular to the interface. When the PB blocks are unable to sufficiently cover the interface and the PEO blocks do not interact homogeneously with PAA chains, the MVVs form.