In the textile industry, chemical finishing of textiles by N-methylol acrylamide (NA) results in tenacious three-dimensional (3D) crosslinked polymer networks which can maintain wrinkle resistance of fabrics. Inspired by this chemical finishing method, we developed herein NA functionalized carboxymethyl cellulose (CMC) binders for Si anodes through free radical graft copolymerization of NA and acrylic acid (AA) onto CMC backbones. In this multifunctional binder, PAA and CMC with a high density of carboxyl groups offer binding ability with Si particles as well as with the copper (Cu) current collectors. Meanwhile, the methylol groups in NA condensate with the hydroxyl groups of CMC to form robust three-dimensional (3D) crosslinked networks. These help maintain integration of Si electrodes and build a stable SEI layer on the Si surface, leading to significant improvement in cycling performance of Si-based lithium ion batteries (LIBs) (94% capacity retention after 250 cycles). The high elastic modulus of the binders and weak interaction between the electrolyte and the binders are thought to account for the enhanced electrochemical performance of Si-based LIBs.

•In situ hydrolysis of tetraethoxysilane within the confined galleries region of graphite oxide.•New porous sandwiched graphene/Si nanocomposites were prepared by magnesium thermal reduction.•The Si nanostructure was compactly sandwiched between two neighboring graphenes.•The Si/graphene anodes deliver large reversible capacity with excellent cycling stability.Porous sandwiched graphene/Si nanocomposites (PG-Si) are prepared by in situ hydrolysis of tetraethoxysilane within the confined gallery region of graphite oxide, and then magnesium thermal reduction of the intra-gallery SiO2 to Si nanocrystals. The Si nanostructures are in situ formed within the confined gallery region of graphite, and they are compactly sandwiched between two neighboring graphene sheets. This compactly sandwiched structure affords enhanced electron conductivity, and prevents Si nanoparticles from aggregation. Meanwhile, the free voids between neighboring Si nanocrystals alleviate the volume change of Si during cycling. As a consequence, the resulting PG-Si nanocomposites are high-performance anode materials for lithium-ion batteries which show long cycle life (>500 cycles) and high specific charge capacity (1464 mAh g−1 at a current density of 200 mA/g, 920 mAh g−1 at a current density of 1.68A/g after 500 cycles). The Li+ diffusion kinetics in PG-Si is also discussed.

We report the synthesis of a two-dimensional enamine-linked covalent organic framework (COF) using a rapid microwave-assisted solvothermal method in significantly less time and high yield under a relatively low temperature. This COF was found to have a high crystallinity, high stability, high BET surface area, and a high CO2 capacity and adsorption selectivity of CO2/N2.

•The side-contacted CNT/Ti contact and end-contacted CNT/TiC contact are investigated.•The CNT/TiC contact shows much lower contact resistance than the CNT/Ti contact.•The contact resistance between TiC and metallic CNT can be low down to ~6.8 kΩ.•The transmission coefficient and resistance of different kinds of contacts are calculated.•The contact characteristics are illustrated by wave-vector conserved transportation.The contacts of the metallic or semiconducting carbon nanotubes (CNTs) and the Ti (side-contacted type) or TiC (end-contacted type) have been investigated by non-equilibrium Green׳s function approach. The transmission coefficient and resistance of the contacts are calculated. The study shows the contact resistance between TiC and metallic or semiconducting CNT is 2 and 4 orders of magnitude lower than that between Ti and metallic or semiconducting CNT, respectively. The contact resistance between TiC and metallic CNT can be low down to ~6.8 kΩ. The contact characteristics are illustrated by the wave-vector conservation of electron transportation between CNT and metal.

Stratum corneum is the main obstacle for drugs to pass through the skin. Microneedles are composed of arrays of micro-projections formed with different materials, generally ranging from 25–2000 μm in height. Microneedles straightly pierce the skin with its short needle arrays to overcome this barrier. Microneedles can be divided into several categories, for instance, solid microneedles, coated microneedles, and hollow microneedles and so on. However, all these types have their weak points related to corresponding mechanisms. In recent years, pioneering scientists have been working on these issues and some possible solutions have been investigated. This article will focus on the microneedle arrays consisting of hydrogels. Hydrogels are commonly used in drug delivery field. Hydrogel microneedles can be further divided into dissolving and degradable microneedles and phase transition microneedles. The former leaves drug with matrix in the skin. The latter has the feature that drugs in the matrix are delivered while the remaining ingredients can be easily removed from the skin after usage. For drugs which are required to be used every day, the phase transition microneedles are more acceptable. This article is written in order to summarize the advantages of these designs and summarize issues to be solved which may hinder the development of this technology.

•Mesoporous silica is assembled within the interlayer space of GO.•The mesoporous silica is compactly sandwiched between two graphene nanosheets.•The pore size of silica depending on chain length of intercalated surfactants.•A single line of aligned silica mesopores orients parallel to galleries of GO.A new class of mesoporous silica/graphene nanocomposites (MSGs) with a compact sandwich structure is prepared by assembly of mesoporous silica within the interlayer space (galleries) of graphite oxide (GO) using intercalated surfactants as a template. This gallery-templated synthesis involves the use of intercalated ammonium cation surfactants and neutral amines as co-surfactants to direct the hydrolysis and condensation of inorganic precursors (tetraethoxysilane, TEOS) within the galleries of GO. The confinement effects endowed by the galleries of GO make the mesoporous silica framework compactly sandwiched between the adjacent graphene sheets, and a single line of aligned mesopores parallel to the galleries of GO is observed. Depending on the chain length of the intercalated surfactants, the pore sizes of MSGs vary from 1.2 to 2.1 nm. Our gallery templated method to synthesize graphene-based nanocomposites might lead to a broad range of porous graphene-based nanocomposites with unique morphologies and properties.

We report the synthesis of a two-dimensional enamine-linked covalent organic framework (COF) using a rapid microwave-assisted solvothermal method in significantly less time and high yield under a relatively low temperature. This COF was found to have a high crystallinity, high stability, high BET surface area, and a high CO2 capacity and adsorption selectivity of CO2/N2.