Reactive Template-Induced Self-Assembly to Ordered Mesoporous Polymeric and Carbonaceous Materials

As an important method for preparing ordered mesoporous polymeric and carbonaceous materials, the organic template directed self-assembly is facing challenges because of the weak noncovalent interactions between the organic templates and the building blocks. Herein we develop a novel reactive template-induced self-assembly procedure for fabrication of ordered mesoporous polymer and carbon materials. In our approach, the aldehyde end-group of reactive F127 template can react with the resol building block to <i>in-situ</i> form a stable covalent bond during the self-assembly process. This is essential for an enhanced interaction between the resol and the template, thus leading to the formation of an ordered body-centered cubic mesostructure. We also show that the ordered mesoporous carbon product exhibits superior capacitive performance, presenting an attractive potential candidate for high performance supercapacitor electrodes

Band‐Aid‐Like Self‐Fixed Barrier Membranes Enable Superior Bone Augmentation

Abstract In guided bone regeneration surgery, a barrier membrane is usually used to inhibit soft tissue from interfering with osteogenesis. However, current barrier membranes usually fail to resist the impact of external forces on bone‐augmented region, thus causing severe displacement of membranes and their underlying bone graft materials, eventually leading to unsatisfied bone augmentation. Herein, a new class of local double‐layered adhesive barrier membranes (ABMs) is developed to successfully immobilize bone graft materials. The air‐dried adhesive hydrogel layers with suction‐adhesion properties enable ABMs to firmly adhere to the wet bone surface through a “stick‐and‐use” band‐aid‐like strategy and effectively prevent the displacement of membranes and the leakage of bone grafts in uncontained bone defect treatment. Furthermore, the strategy is versatile for preparing diverse adhesive barrier membranes and immobilizing different bone graft materials for various surgical regions. By establishing such a continuous barrier for the bone graft material, this strategy may open a novel avenue for designing the next‐generation barrier membranes

Clay minerals derived nanostructured silicon with various morphology: Controlled synthesis, structural evolution, and enhanced lithium storage properties

Nanostructuring is an effective strategy to enhance the structural and cycling stability of silicon anodes in lithium -ion batteries. However, a controllable and cost-effective method for synthesizing nanostructured silicon with various morphology is still a challenge. Herein, we synthesize zero-dimensional, two-dimensional, and three-dimensional silicon nanostructures directly using low-cost and abundant clay minerals as precursors without any pretreatment and templates. Our results show that the morphology and microstructure of the resulting nanostructured silicon strongly depend on the architectural features of clay minerals, i.e., zero-dimensional silicon from palygorskite, two-dimensional silicon from montmorillonite, and three-dimensional silicon from halloysite. The silicon nanostructures show large specific surface area (over 80 m(2) g(-1)) and hierarchical pore structure. As anodes in lithium-ion batteries, two-dimensional nanostructured silicon from montmorillonite exhibits the best electrochemical performance (i.e., 1369 mAh g(-1) at 1.0 A g(-1) with a capacity retention of 78% over 200 cycles). This work provides a universal guideline from clay minerals to various silicon nanostructures via an economical and scalable strategy, and reveals the fundamental structure-property relationship of different silicon nanostructures synthesized under the same condition, which would contribute to the large-scale production of high-performance and low-cost silicon-based anodes in lithium-ion batteries

Cuentos y anécdotas de toros y toreros : chascarrillos, historietas, agudezas, frases, aforismos y otras menudencias

Nanostructured silicon is an attractive anode material for next-generation lithium-ion batteries, but its commercialization remains a challenge owing to the energy-intensive, costly, and complex preparation of nanostructured silicon. Herein, one-dimensional (1D) silicon nanorods (SNRs) have been synthesized from natural sepiolite by a simple self-templating synthesis method. The intrinsic crystal structure and chemical composition of sepiolite allow for the maintenance of 1D structures during magnesiothermic reduction without any additional templates and heat scavengers. The as-prepared SNRs showed a large specific surface area (similar to 122 m(2) g(-1)) and hierarchical porous structure (i.e., macro-and meso-pores). As anodes for lithium-ion batteries, SNRs exhibited a high reversible capacity of 1350 mA h g(-1) at 1.0 A g(-1) after 100 cycles, and 816 mA h g(-1) at 5.0 A g(-1) after 500 cycles (with a capacity retention of 98%). With a low-cost precursor and facile approach, this strategy for synthesizing 1D nanostructured Si would be promising in practical production of high-performance anode materials for lithium-ion batteries

Fabrication, Characterization, and Biocompatibility of Polymer Cored Reduced Graphene Oxide Nanofibers

Graphene nanofibers have shown a promising potential across a wide spectrum of areas, including biology, energy, and the environment. However, fabrication of graphene nanofibers remains a challenging issue due to the broad size distribution and extremely poor solubility of graphene. Herein, we report a facile yet efficient approach for fabricating a novel class of polymer core-reduced graphene oxide shell nanofiber mat (RGO–CSNFM) by direct heat-driven self-assembly of graphene oxide sheets onto the surface of electrospun polymeric nanofibers without any requirement of surface treatment. Thus-prepared RGO–CSNFM demonstrated excellent mechanical, electrical, and biocompatible properties. RGO–CSNFM also promoted a higher cell anchorage and proliferation of human bone marrow mesenchymal stem cells (hMSCs) compared to the free-standing RGO film without the nanoscale fibrous structure. Further, cell viability of hMSCs was comparable to that on the tissue culture plates (TCPs) with a distinctive healthy morphology, indicating that the nanoscale fibrous architecture plays a critically constructive role in supporting cellular activities. In addition, the RGO–CSNFM exhibited excellent electrical conductivity, making them an ideal candidate for conductive cell culture, biosensing, and tissue engineering applications. These findings could provide a new benchmark for preparing well-defined graphene-based nanomaterial configurations and interfaces for biomedical applications

Biocompatible Cryogel with Good Breathability, Exudate Management, Antibacterial and Immunomodulatory Properties for Infected Diabetic Wound Healing

Abstract Due to the complex microenvironment and healing process of diabetic wounds, developing wound dressing with good biocompatibility, mechanical stability, breathability, exudate management, antibacterial ability, and immunomodulatory property is highly desired but remains a huge challenge. Herein, a multifunctional cryogel is designed and prepared with bio‐friendly bacterial cellulose, gelatin, and dopamine under the condition of sodium periodate oxidation. Bacterial cellulose can enhance the mechanical stability of the cryogel by improving the skeleton supporting effect and crosslinking degree. The cryogel shows outstanding breathability and exudate management capability thanks to the interpenetrated porous structures. I2 and sodium iodides produced in situ by reduction of sodium periodate provide efficient antibacterial properties for the cryogel. The cryogel facilitates macrophage polarization from M1 to M2, thus regulating the immune microenvironment of infected diabetic wounds. With these advantages, the multifunctional cryogel effectively promotes collagen deposition and neovascularization, thus accelerating the healing of infected diabetic wounds

In situ synthesis of a silicon flake/nitrogen-doped graphene-like carbon composite from organoclay for high-performance lithium-ion battery anodes

A silicon flake/nitrogen-doped graphene-like carbon composite was prepared from organoclay via an in situ strategy, involving carbonization followed by low-temperature aluminothermic reduction. The preformed carbon sheets within the confined interlayer space of clay acted as nanotemplates for in situ synthesizing silicon flakes. As a lithium-ion battery anode, the composite exhibited excellent electrochemical properties

Hydrogel Encapsulating Wormwood Essential Oil with Broad‐spectrum Antibacterial and Immunomodulatory Properties for Infected Diabetic Wound Healing

Abstract The integration of hydrogels with bio‐friendly functional components through simple and efficient strategies to construct wound dressings with broad‐spectrum antibacterial and immunomodulatory properties to promote the healing of infected diabetic wounds is highly desirable but remains a major challenge. Here, wormwood essential oil (WEO) is effectively encapsulated in the hydrogel via an O/W‐Pickering emulsion during the polymerization of methacrylic anhydride gelatin (GelMA), acrylamide (AM), and acrylic acid N‐hydroxysuccinimide ester (AAc‐NHS) to form a multifunctional hydrogel dressing (HD‐WEO). Compared with conventional emulsions, Pickering emulsions not only improve the encapsulation stability of the WEO, but also enhance the tensile and swelling properties of hydrogel. The synergistic interaction of WEO's diverse bioactive components provides a broad‐spectrum antibacterial activity against S. aureus, E. coli, and MRSA. In addition, the HD‐WEO can induce the polarization of macrophages from M1 to M2 phenotype. With these advantages, the broad‐spectrum antibacterial and immunomodulatory HD‐WEO effectively promotes the collagen deposition and neovascularization, thereby accelerating the healing of MRSA‐infected diabetic wounds