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Three-dimensional bioprinting is a potent biofabrication technique in tissue engineering but is limited by inadequate bioink availability. Plant-derived proteins are increasingly recognized as highly promising yet underutilized materials for biomedical product development and hold potential for use in bioink formulations. Herein, we report the development of a biocompatible plant protein bioink from pea protein isolate. Through pH shifting, ethanol precipitation, and lyophilization, the pea protein isolate (PPI) transformed from an insoluble to a soluble form. Next, it was modified with glycidyl methacrylate to obtain methacrylate-modified PPI (PPIGMA), which is photocurable and was used as the precursor of bioink. The mechanical and microstructural studies of the hydrogel containing 16% PPIGMA revealed a suitable compress modulus and a porous network with a pore size over 100 μm, which can facilitate nutrient and waste transportation. The PPIGMA bioink exhibited good 3D bioprinting performance in creating complex patterns and good biocompatibility as plenty of viable cells were observed in the printed samples after 3 days of incubation in the cell culture medium. No immunogenicity of the PPIGMA bioink was identified as no inflammation was observed for 4 weeks after implantation in Sprague Dawley rats. Compared with methacrylate-modified gelatin, the PPIGMA bioink significantly enhanced cartilage regeneration in vitro and in vivo, suggesting that it can be used in tissue engineering applications. In summary, the PPIGMA bioink can be potentially used for tissue engineering applications. [ABSTRACT FROM AUTHOR]

Organic contamination of water results in significant risks to the biosphere and human health. The treatment of organic pollutants found in effluents urgently requires a green, sustainable, and effective approach. Herein, a straightforward one-step procedure was developed to create a photocatalytic mesh using iron mesh as the substrate and the g-C3N4/MIL-101(Fe) heterostructure as the photocatalytic material to activate persulfate (PS) for the removal of methyl orange (MO) from water. Fluorescence stereo microscopy (FSM), scanning electron microscopy (SEM), nitrogen adsorption–desorption, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) spectroscopy, and X-ray powder diffraction (XRD) were used to characterize the morphological and physicochemical properties of the synthesized composites, which confirmed the successful growth of g-C3N4/MIL-101(Fe) on the iron mesh. The outstanding PS activation capacity of g-C3N4/MIL-101(Fe) promoted electron transfer and accelerated the generation of SO4˙−, resulting in up to 91.05% MO degradation under 60 min of visible light exposure. The removal mechanisms were investigated by quenching experiments and electron spin resonance (ESR), which proved that ˙OH, ˙O2− and h+ contributed to the removal of MO. Moreover, the degradation pathways of MO and the as-formed intermediates were identified by high-resolution mass spectroscopy (HRMS). This study provides a convenient and economical method to build innovative photocatalytic systems for organic pollutant degradation. [ABSTRACT FROM AUTHOR]

Particle-free metal–organic-decomposition inks, especially amine-coordinated copper formate compounds, can be employed as highly conductive binder precursors to replace the commonly used polymer adhesives. Herein, we used the copper formate complex (Cuf-C) as the conductive binder precursor instead of organic binders and dispersants to prepare a series of composite inks. The lowest voltage solid block resistance of the graphene composite conductive ink was 7.34 Ω per sq per mil. In addition, we applied the pyrolysis products of Cuf-C to the cathode of lithium-ion batteries as conductive binder. Compared with the traditional poly(vinylidene fluoride) binder, the battery with the Cuf-C binder displayed lower charge transfer resistance and interface impedance at the cathode/electrolyte interface, as well as lower polarization and better electrochemical kinetics. We also observed the positive effect of the Cuf-C binder on the cathode in finite element simulation. [ABSTRACT FROM AUTHOR]

Cell mechanical properties provide a label-free marker for indicating cell states and disease processes. Although microfluidic deformability cytometry has demonstrated great potential and successes in mechanical phenotyping in recent years, its universal applicability for characterizing multiple sizes of cells using a single device has not been realized. Herein, we propose high-throughput adjustable deformability cytometry integrated with three-dimensional (3D) elasto-inertial focusing and a virtual fluidic channel. By properly adjusting the flow ratio of the sample and sheath, the virtual fluidic channel in a wide solid channel can generate a strong shear force in the normal direction of the flow velocity and simultaneously squeeze cells from both sides to induce significant cell deformation. The combination of elasto-inertial focusing and a virtual fluidic channel provides a great hydrodynamic symmetrical force for inducing significant and homogeneous cell deformation. In addition, our deformability cytometry system not only achieves rapid and precise cell deformation, but also allows the adjustable detection of multiple sizes of cells at a high throughput of up to 3000 cells per second. The mini-bilateral segmentation network (mini-BiSeNet) was developed to identify cells and extract features quickly. The classification of different cell populations (A549, MCF-7, MDA-MB-231, and WBCs) was carried out based on the cell size and deformation. By applying deep learning to cell classification, a high accuracy reaching approximately 90% was achieved. We also revealed the potential of our deformability cytometry for characterizing pleural effusions. The flexibility of our deformability cytometry holds promise for the mechanical phenotyping and detection of various biological samples. [ABSTRACT FROM AUTHOR]

Composite polymer electrolytes (CPEs) are considered the most promising all-solid-state battery (ASSB) electrolytes. However, they are limited by their low ionic conductivity and poor stability with Li metal. Herein, highly dispersed and surface-functionalized active boron nitride nanosheets (BNNSs) were prepared using the boric acid assisted ball milling method, and only a small amount of addition (3%) could significantly improve the physical and electrochemical properties of CPEs. The uniform dispersion of BNNSs forms fast lithium-ion transport pathways, significantly improving the ionic conductivity (6.7 × 10−6 S cm−1 at 30 °C, 2.77 × 10−4 S cm−1 at 50 °C). The excellent thermal conductivity of BNNSs avoids the space-charge region accumulation caused by the agglomeration of inorganic fillers, weakens the growth of lithium dendrites, enhances the interface stability, and optimizes the thermal management of the batteries. In addition, improving mechanical properties reduces the risk of short circuits and extends the service life. The LFP/CPE-BNNS/Li battery was optimized by systematically increasing Li+ diffusion, widening the electrochemical stability window, and enhancing interface stability and delivers excellent rate performance (88.7 mA h g−1 at a rate of 2.0C) and perfect cycle stability (160.1 mA h g−1 after 200 cycles at 0.5C and 60 °C with a capacity degradation rate of 0.009% per cycle). Therefore, the CPE-BNNSs created by us would open a new avenue to improve the performance of ASSBs. [ABSTRACT FROM AUTHOR]

With the rapid development of science and technology, it is urgent to develop the extreme condition-resistance and multifunctionality of sensors to broaden their application scenarios. Here, an extreme condition-resistant superelastic silica nanofiber (SNF)/MXene composite aerogel is fabricated by an ice-templating assembly strategy. The hierarchical three-dimensional cellular structure composed of conductive two-dimensional MXene nanosheets as a framework and flexible one-dimensional SNFs as a scaffold endows the composite aerogel with excellent mechanical and piezoresistive properties at an ultralow density of 9 mg cm−3. The assembled aerogel sensor shows a high sensitivity (−0.33 kPa−1), ultralow detection limit (0.01 kPa), rapid response/recover time (72/99 ms), large workable strain range (1–80%), and good stability (>5000 cycles), capable of detecting various human motions in real time, whether faint pulse beating or strenuous running. More importantly, the composite aerogel still maintains excellent mechanical and piezoresistive stability (>1000 cycles) after high-temperature baking (600 °C) or at ultralow temperature (−130 °C), even in liquid nitrogen (−196 °C). Furthermore, the outstanding thermal insulation performance (24.7 mW m−1 K−1) and exceptional low-voltage driven Joule heating performance (126.5 °C at 5 V) of the composite aerogel are presented simultaneously in a dual-mode thermal management device integrating heat generation and insulation. Based on these characteristics, a multifunctional aerogel sensor that can be used for synchronous sensing and thermal management is demonstrated for the first time. This work offers a novel insight into the development of multifunctional aerogel sensors and greatly broadens the application scenarios of wearable devices. [ABSTRACT FROM AUTHOR]

The limited availability of bioinks has hindered the application of 3D bioprinting to tissue engineering, and bacterial infection is a serious threat to these applications. Aiming to solve this problem, a novel ε-poly- L -lysine (EPL)-derived antibacterial bioink has been developed for 3D bioprinting and tissue-engineering applications. Three glycidyl methacrylate (GMA)-modified EPL products, EPLGMA-1, EPLGMA-2, and EPLGMA-3, were prepared by reacting 3, 4, and 5 mL GMA with 5 g EPL, respectively. EPLGMA-1, EPLGMA-2, and EPLGMA-3 were photocurable and their corresponding photo-crosslinked hydrogels, EPLGMA-1H, EPLGMA-2H, and EPLGMA-3H, all exhibited very high antibacterial rates, good biocompatibility, good degradability, and promising mechanical properties. After EPLGMA-1H, EPLGMA-2H, and EPLGMA-3H with encapsulated chondrocytes were incubated for 4 weeks, EPLGMA-3H was the best one among them for tissue-engineering applications due to its most efficient tissue regeneration. Carrying chondrocytes, the EPLGMA-3 solution was printed into hydrogel products with high-fidelity shapes and high cell viability using a projection-based 3D bioprinter. Following the implantation of chondrocyte-loaded EPLGMA-3H samples into nude mice for 4 weeks, cartilage-like tissue was regenerated, suggesting that EPLGMA-3 is a promising antibacterial bioink for 3D bioprinting and tissue-engineering applications. [ABSTRACT FROM AUTHOR]

3D bioprinting is a major area of interest in health sciences for customized manufacturing, but lacks specific bioinks to enhance the shape fidelity of 3D bioprinting and efficiency of tissue repair for particular clinical purposes. A naringin derived bioink, which contains 1.5 mM methylacryloyl naringin and 0.15 mM methylacryloyl gelatin, improves the fidelity of 3D bioprinting due to 405 nm light absorption of methylacryloyl naringin. The naringin derived bioink promotes the growth of chondrocytes due to preserving bioactivities of naringin and functions as a medical ingredient from which it has been described as a medical bioink in this study. It facilitates cartilage regeneration by upregulating the transcription of chondrogenesis-related genes like SOX9 and genes against oxidative stress like SOD1 and SOD2 and maintains chondrocytes active resulting from the significantly enhanced COL II/COL I ratio. According to a rabbit cartilage defect model, the proposed naringin derived medical bioink significantly improves the efficiency and quality of cartilage defect repair, suggesting that the bioink is suitable for cartilage defect repair applications and a feasible strategy is provided for the formulation of medical bioinks for specific clinical purposes. [ABSTRACT FROM AUTHOR]

Unusual intermolecular π-stacking in a new charge transfer salt of pyrene (Py), (Py)2+(Ga2Cl7)−, has been observed. The structure obtained by single crystal X-ray crystallography indicates π-stacks of pyrene which were analyzed using a combination of density functional theory and the analysis of the bond length alternation patterns in the pyrene molecules in different charge states. There are relatively few crystal structures of charge transfer salts of pyrene in the literature, and this structure shows a unique charge separation in which half of the pyrenes are nearly neutral while the other half carry approximately +1 charge in an alternating fashion along the 1D stacks balancing one electron charge transfer to each (Ga2Cl7)− anion. The charge localization is attributed to the incomplete inter-pyrene overlap of the singly occupied molecular orbitals. [ABSTRACT FROM AUTHOR]

The chemical reduction of a corannulene-based molecular nanographene, C76H64 (1), with Na metal in the presence of 18-crown-6 afforded the doubly-reduced state of 1. This reduction provokes a distortion of the helicene core and has a significant impact on the aromaticity of the system. [ABSTRACT FROM AUTHOR]

The chemical reduction of a π-expanded COT derivative, octaphenyltetrabenzocyclooctatetraene (1), with lithium or sodium metals in the presence of secondary ligands affords a new doubly-reduced product (1TR2−). The X-ray diffraction study revealed a reductive core rearrangement accompanied by the formation of a single C–C bond and severe twist of the central tetraphenylene core. The reversibility of two-electron reduction and core transformation is further confirmed by NMR spectroscopy and DFT calculations. [ABSTRACT FROM AUTHOR]

Glycerol hydrogenolysis to 1,3-propanediol is identified to follow the dehydration-hydrogenation pathway with the rate-determining step (RDS) of H* + OH* → H2O* over an IrRe catalyst. The positive effects of solid acids are elucidated to originate from the reduced energy barrier of the RDS by H protons, while the negative ones of liquid acids are from excessively strong adsorption of anions. [ABSTRACT FROM AUTHOR]

Since it was first proposed in 2007, inertial microfluidics has been extensively studied in terms of theory, design, fabrication, and application. In recent years, with the rapid development of microfabrication technologies, a variety of channel structures that can focus, concentrate, separate, and capture bioparticles or fluids have been designed and manufactured to extend the range of potential biomedical applications of inertial microfluidics. Due to the advantages of high throughput, simplicity, and low device cost, inertial microfluidics is a promising candidate for rapid sample processing, especially for large-volume samples with low-abundance targets. As an approach to cellular sample pretreatment, inertial microfluidics has been widely employed to ensure downstream cell analysis and detection. In this review, a comprehensive summary of the application of inertial microfluidics for high-throughput cell analysis and detection is presented. According to application areas, the recent advances can be sorted into label-free cell mechanical phenotyping, sheathless flow cytometric counting, electrical impedance cytometer, high-throughput cellular image analysis, and other methods. Finally, the challenges and prospects of inertial microfluidics for cell analysis and detection are summarized. [ABSTRACT FROM AUTHOR]

This study proposes a simple method to prepare a pH-responsive and shape memory hydrogel based on cooperative hydrophobic interaction and hydrogen bonding. Acryloyl 11-aminoundecanoic acid (A11AUA) and acrylamide were selected as hydrophobic monomers and hydrophilic monomers, respectively. The mechanical properties of the prepared hydrogel strongly depend on the pH. Under acidic conditions, the maximum tensile strength of the hydrogel can reach 7.8 MPa, and the tensile modulus of the hydrogel can be increased by more than 10 000 times. The mechanical properties of acidic gels are affected by temperature and exhibit a temperature-controlled shape memory function. The acidic gel is immersed in NaOH and HCl solutions in sequence to achieve the function of reprogramming. Hydrogels under alkaline and neutral conditions exhibit conductivity and adhesion properties controlled by pH. Using the hydrogel as an adhesive electrode, the performance of the hydrogel in monitoring human electrophysiological signals was discussed. [ABSTRACT FROM AUTHOR]

We report the charge transport in pentacene polycrystalline organic thin film transistors (OTFTs) with different active layer thicknesses, ranging from a sub-monolayer, bilayer, to tens of nanometers by employing a novel electrode-contact architecture. Temperature dependent electrical characterization is systematically carried out to elucidate the carrier transport mechanisms of OTFTs based on various active layer thicknesses. The mobilities of charge carriers in the GB region of the whole channels are extracted and analyzed by utilizing a two-dimensional (2D) grain boundary model (2DGB). The roles of grain boundaries (GBs) in electrical behavior should be to some degree reduced as the second layer begins to form. Due to the vertical interlayer transfer via which charge carriers can bypass the most resistant GB regions, the conductance path energetic disorder degree is reduced, simultaneously, the hopping transport undergoes crossover from the 2D to 3D one. Our results will deepen the understanding of the interface charge transport in the OTFTs, and provide pathways for organic material and device optimization. [ABSTRACT FROM AUTHOR]

Herein, we have managed to conceive and fabricate a core–shell structured triangle-like array, where a selenylation-treated MOF array was grown in situ on a conducting substrate as a highly conductive framework to support a high loading of Mo-doped nickel–cobalt LDH nanoflakes. This hierarchical electrode integrates the advantages of a defect-rich electronic state, large active area and rich reaction sites, delivering a high areal capacity of 5.16 C cm−2 and a high rate capability. [ABSTRACT FROM AUTHOR]

Cu2ZnSn(S,Se)4 (CZTSSe) solar cells have been receiving considerable attention in recent years, owing to their low cost and toxicity as well as a high abundance of their constituent elements. Solution-based (mainly precursor solution) methods have been widely used in the fabrication of CZTSSe-based thin film solar cells. Though most record solar cells since 2009 have been achieved using solution-based methods, carbonaceous residues are always formed during post deposition treatment (PDT). These carbonaceous residues are detrimental to grain growth of CZTSSe to form large grains. The presence of unwanted small grain layers will increase the series resistance and reduce the fill factor of the solar cell, thus consequently decreasing the efficiency of CZTSSe solar cells. Herein, we propose "green" supercritical carbon dioxide (SCCO2) treatment to overcome the challenge of carbonaceous residues. FT-IR, SEM, XRD and Raman characterization studies were used to confirm the reduction of carbonaceous residues in CZTSSe films. The solar cell fabricated from a selenized CZTSSe precursor film with SCCO2 treatment under optimal conditions showed the best conversion efficiency of 11.23% (VOC = 0.456 V, JSC = 36.6 mA cm−2, FF = 67.1%). To the best of our knowledge, this is the first report on boosting the efficiency of solution-based CZTSSe solar cells by using SCCO2 treatment. In addition, this unique SCCO2 treatment may also bring forth new ideas for other solution-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Two new Cu-based MOFs have been effectively isolated and structurally characterized. Interestingly, it was found that the presence of an "open metal site" in compound 1 is able to effectively improve the catalytic hydrogenation performance, thus exhibiting 8-fold and 16-fold higher activity than compound 2 and CuO nanoparticles, respectively. In addition, compound 1 also displayed high thermal and water stability, and it could be reused more than eight times without an obvious decrease in activity, suggesting a way to enhance future catalysts with structural control. [ABSTRACT FROM AUTHOR]

Based on the well-established model structure of Li2M2(tbaoac)6, the first series of heterometallic molecular precursors Na2M2(tbaoac)6(THF)2 (M = Fe, Co, and Ni) have been designed and successfully utilized for the preparation of NaMO2 oxide cathode materials of sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Two new organometallic cyclooctatetraenyl complexes of the type [M2(COT)3(THF)2] (M = Y and La) have been prepared, using optimized synthetic procedures, and fully characterized by X-ray diffraction analysis, IR and 1H NMR spectroscopies. The structures can be represented as formed by the double-decker [M(COT)2]− anion with an asymmetrically bound cationic [M(COT)(THF)2]+ unit. The COT rings in the anionic sandwich are not equidistant from the metal with the M–COTcentroid distances measuring at 1.991(5) Å and 2.074(5) Å for [Y(COT)2]−vs. 2.045(4) Å and 2.154(5) Å for [La(COT)2]−. The sandwich fragments are η2-coordinated to the second metal center with the average M–C distances of 2.837(4) Å and 2.879(5) Å for yttrium and lanthanum complexes, respectively. The M–COTcentroid distances in the cationic unit are 1.962(4) Å for the former and 2.009(2) Å for the latter. [ABSTRACT FROM AUTHOR]

Transition metal boride (TMB) materials have recently gained vast interest as a new class of catalysts. However, their catalytic performance is still limited due to poor electrical conductivity and limited specific surface area. Here, we demonstrate a generalizable approach to overcome these limitations by anchoring ultrathin nickel boride (NixB) sheets on the surfaces of functionalized small-diameter multi-walled carbon nanotubes (f-MWCNTs). The electrochemically active surface area and charge transfer resistance of the resulting hybrid materials (NixB/f-MWCNT) is 3.4 and 0.24 times that of the NixB nanosheets, respectively. And, NixB/f-MWCNT exhibited superior catalytic activities and stability toward both oxygen evolution and hydrogen evolution reactions. For the overall water splitting, it requires a cell voltage of 1.60 V to reach the current density of 10 mA cm−2, outperforming existing metal boride catalysts as well as commercial IrO2/Pt/C catalysts. Further, X-ray photoelectron spectroscopy revealed the strong chemical coupling between NixB and f-MWCNTs and the in situ formation of highly active NiOOH/NixB and Ni(OH)2/NixB heterojunctions, which contributes to the superior activity. The developed design concept can serve as a general approach to improve other electrocatalysts with low electrical conductivity and specific surface area, such as metal oxides, metal hydroxides, and metal–organic framework-derived materials. [ABSTRACT FROM AUTHOR]

Pd(ii)-Catalyzed direct C(sp3)–H germylation of α-AA derivatives with the assistance of a bidentate auxiliary for the efficient synthesis of β-germyl-α-amino amides is reported. This protocol features good generality for primary and secondary C–H bonds of aliphatic amides. Mechanistic studies show that a crucial five-membered palladacycle intermediate may play a key role in this process. [ABSTRACT FROM AUTHOR]

Herein, we report on the elaborate synthesis of a novel hybrid architecture, i.e., black tin oxide–black titanium oxide core–shell nanotubes (denoted as TiO2−x@SnO2−x nanotubes) by NaBH4 co-reduction. The synergistic interplay between the SnO2−x core and the TiO2−x shell results in superior cyclability and rate capability for ultrastable and fast lithium storage. [ABSTRACT FROM AUTHOR]

TiO2(B) nanosheets exhibit high theoretical capacity and excellent cyclability for lithium storage, but suffer from disappointing rate capabilities because of their inherently low electronic and ionic conductivities as well as strong tendency to aggregate. Here we propose a universal strategy for the in situ synthesis of TiO2(B) nanosheets on pristine carbon nanomaterials, e.g., pristine graphene nanosheets (PGNSs) and pristine carbon nanotubes (PCNTs), with the help of a multifunctional linker (SDBS). The resulting TiO2(B)@PGNS and TiO2(B)@PCNT nanohybrids energetically integrate the appealing merits of the two building blocks. Pristine carbon nanomaterials play three vital roles: first, they serve as high-efficiency conductive dopants to provide sufficient pathways for electrons and Li+ ions. Second, they act as flexible matrices to immobilize TiO2(B) nanosheets and thus prevent them from aggregation. Last but not least, they can make a substantial capacity contribution. TiO2(B) nanosheets, on the other hand, function not only as a major active material to achieve high structural stability and excellent cyclability, but also as spacers to isolate the pristine carbon nanomaterials from agglomeration. Benefiting from a remarkable synergistic effect, these two nanohybrids exhibit superior electrochemical lithium storage performance, particularly high-rate performance, delivering reversible capacities of 573 and 536 mA h g−1 at 1 A g−1, and 371 and 349 mA h g−1 at 5 A g−1, respectively. In this sense, our strategy may open the door to next-generation, high-power and high-energy anode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The nickel phosphide (Ni2P) family of materials have become a hot subject in hydrogen evolution reaction (HER) electrocatalyst research. Various studies have reported their high activity, high stability, and high faradaic efficiency. To date, there have been no systematic studies regarding the influence of pH on the HER performance of Ni2P. Here we show that the pH of electrolytes can strongly influence the HER activity of Ni2P electrocatalysts. Tests in 19 electrolytes with pH ranging from 0.52 to 13.53 show that Ni2P is much more active in strongly acidic and basic electrolytes. With the increase of pH, the lower H+ concentration reduces the formation of adsorbed H atoms in the Volmer reaction, resulting in poorer activities. However, the high activity observed in the strongly basic electrolytes is not the intrinsic property of Ni2P. We found that Ni oxides/hydroxides are formed in strongly basic electrolytes under applied potentials, resulting in improved activities. Furthermore, the specific activity based on the electrochemically active surface area of recently reported Ni2P catalysts is not high and requires significant improvements for practical applications. [ABSTRACT FROM AUTHOR]

Increasing atmospheric CO2 concentration has become a cause for concern. The design of efficient and stable solid amine adsorbents for CO2 capture, as well as for controlled release, is urgently needed. Polymeric amine modified multiwalled carbon nanotubes (CNT) are a promising material for meeting these goals. In this study, linear polyethylenimine (LPEI) was supported on CNT and was characterized and studied for reversible CO2 adsorption. These results are compared to branched polythylenimine (BPEI) as well as other materials. Upon treatment with 3 M NaOH or 5 M HNO3, the CO2 adsorption was decreased by at least 15%. The CO2 adsorption by LPEI (1.89 mmol g−1) was lower than that of BPEI (2.43 mmol g−1) when coated on CNT supports. The desorption temperature was noticeably lower on CNT–LPEI versus CNT–BPEI for complete CO2 removal. CO2 adsorption capacity was strongly dependent on the packing height of the material in the column reactor. The stability study showed that CO2 adsorption of CNT–LPEI and CNT–BPEI decrease by 9.5% and 61.7%, respectively, after steam treatment, indicating that LPEI was more stable under humid conditions. [ABSTRACT FROM AUTHOR]

Copper catalysts with an imidazole salt tag ([Cu-Imace-R-H][X], X− = F−, Cl−, Br−, I−, CF3CO2−, HSO4−, NO3−, PF6− or BF4−; R = H or CH3) show quite high reactivity for the oxidation of non-aromatic olefins with good selectivity for epoxides. The reactions perform well with a part per million (ppm) catalyst loading at mild temperature and ambient pressure. The highest turnover frequency (TOF) reaches up to 900 000 h−1. The catalytic activity is easy to control by changing the anion of [Cu-Imace-R-H][X]. This catalyst is effective for a series of substrates, including internal and terminal olefins, tri- and tetra-substituted olefins and aromatic olefins. In addition, the copper catalyst can be conveniently separated from the reaction system and reused for at least six cycles without any obvious loss of catalytic activity. [ABSTRACT FROM AUTHOR]

We report the aluminothermic reduction enabled synthesis of silicon hollow microspheres from commercialized silica nanoparticles by controlled transformation and organization. The synergistically integrated merits of a simple process and delicate structural design lay a basis for developing an industrially viable silicon anode with optimized electrochemical performances. [ABSTRACT FROM AUTHOR]

Stimuli-responsive hydrogels are soft, biocompatible and smart biomaterials; however, the poor mechanical properties of the hydrogels limit their application. Herein, we prepared a reductant- and light-responsive polyurethane hydrogel which was made of polyethylene glycol, 1,6-diisocyanatohexane, azobenzene, cyclodextrin and disulfide. Attenuated Total Reflectance Infrared Spectra and 1H NMR were used to characterize the structure of the hydrogel. The hydrogel has a high elasticity (a tensile modulus of 36.5 ± 0.5 kPa and a storage modulus of 52.9 ± 1.2 kPa) at a high water content (91.2 ± 0.4%). Swelling, mechanical and rheological properties of the hydrogel can be tuned by the content of the crosslinker, light and reductant. The hydrogel has low cytotoxicity and it can be used for drug delivery. Ultraviolet irradiation helped to load drugs and the reductant accelerated the drug release. With its high mechanical properties and light- and reductant-responsiveness, the hydrogel is hopefully to be used as a drug carrier. [ABSTRACT FROM AUTHOR]