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Metal phosphides are a new class of potential high‐capacity anodes for lithium ion batteries, but their short cycle life is the critical problem to hinder its practical application. A unique ball‐cactus‐like microsphere of carbon coated NiP2/Ni3Sn4 with deep‐rooted carbon nanotubes (Ni‐Sn‐P@C‐CNT) is demonstrated in this work to solve this problem. Bimetal‐organic‐frameworks (BMOFs, Ni‐Sn‐BTC, BTC refers to 1,3,5‐benzenetricarboxylic acid) are formed by a two‐step uniform microwave‐assisted irradiation approach and used as the precursor to grow Ni‐Sn@C‐CNT, Ni‐Sn‐P@C‐CNT, yolk–shell Ni‐Sn@C, and Ni‐Sn‐P@C. The uniform carbon overlayer is formed by the decomposition of organic ligands from MOFs and small CNTs are deeply rooted in Ni‐Sn‐P@C microsphere due to the in situ catalysis effect of Ni‐Sn. Among these potential anode materials, the Ni‐Sn‐P@C‐CNT is found to be a promising anode with best electrochemical properties. It exhibits a large reversible capacity of 704 mA h g?1 after 200 cycles at 100 mA g?1 and excellent high‐rate cycling performance (a stable capacity of 504 mA h g?1 retained after 800 cycles at 1 A g?1). These good electrochemical properties are mainly ascribed to the unique 3D mesoporous structure design along with dual active components showing synergistic electrochemical activity within different voltage windows.  相似文献   

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Organic–inorganic halide perovskites are promising photodetector materials due to their strong absorption, large carrier mobility, and easily tunable bandgap. Up to now, perovskite photodetectors are mainly based on polycrystalline thin films, which have some undesired properties such as large defective grain boundaries hindering the further improvement of the detector performance. Here, perovskite thin‐single‐crystal (TSC) photodetectors are fabricated with a vertical p–i–n structure. Due to the absence of grain‐boundaries, the trap densities of TSCs are 10–100 folds lower than that of polycrystalline thin films. The photodetectors based on CH3NH3PbBr3 and CH3NH3PbI3 TSCs show low noise of 1–2 fA Hz?1/2, yielding a high specific detectivity of 1.5 × 1013 cm Hz1/2 W?1. The absence of grain boundaries reduces charge recombination and enables a linear response under strong light, superior to polycrystalline photodetectors. The CH3NH3PbBr3 photodetectors show a linear response to green light from 0.35 pW cm?2 to 2.1 W cm?2, corresponding to a linear dynamic range of 256 dB.  相似文献   

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The continuous increasing of engineered nanomaterials (ENMs) in our environment, their combinatorial diversity, and the associated genotoxic risks, highlight the urgent need to better define the possible toxicological effects of ENMs. In this context, we present a new high‐throughput screening (HTS) platform based on the cytokinesis‐block micronucleus (CBMN) assay, lab‐on‐chip cell sorting, and automated image analysis. This HTS platform has been successfully applied to the evaluation of the cytotoxic and genotoxic effects of silver nanoparticles (AgNPs) and silica nanoparticles (SiO2NPs). In particular, our results demonstrate the high cyto‐ and genotoxicity induced by AgNPs and the biocompatibility of SiO2NPs, in primary human lymphocytes. Moreover, our data reveal that the toxic effects are also dependent on size, surface coating, and surface charge. Most importantly, our HTS platform shows that AgNP‐induced genotoxicity is lymphocyte sub‐type dependent and is particularly pronounced in CD2+ and CD4+ cells.  相似文献   

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The micro‐supercapacitors are of great value for portable, flexible, and integrated electronic equipments. Here, the large‐scale and integrated asymmetrical micro‐supercapacitor (AMSC) array is fabricated in virtue of the laser direct writing and electrodeposition technology. The AMSC shows the ideal flexibility, high areal specific capacitance (21.8 mF cm?2), and good rate capability. Moreover, its energy density reaches 12.16 µW h cm?2, outperforming most micro‐supercapacitors reported previously. Meanwhile, large‐scale series‐connected AMSCs are integrated on the flexible substrates (e.g., indium tin oxide‐polyethylene terephthalate film), which can power a veriety of the commercial electronics. The combination of AMSCs array, solar cell, and electronic device proves the feasibility for practical application in the portable, flexible, and integrated electronic equipments.  相似文献   

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Digital image correlation (DIC) is of vital importance in the field of experimental mechanics, yet producing suitable DIC patterns for demanding in‐situ (micro)mechanical tests remains challenging, especially for ultrafine patterns, despite the large number of patterning techniques reported in the literature. Therefore, we propose a simple, flexible, one‐step technique (only requiring a conventional physical vapour deposition machine) to obtain scalable, high‐quality, robust DIC patterns, suitable for a range of microscopic techniques, by deposition of a low‐melting temperature solder alloy in the so‐called island growth mode, without elevating the substrate temperature. Proof of principle is shown by (near‐)room temperature deposition of InSn patterns, yielding highly dense, homogeneous DIC patterns over large areas with a feature size that can be tuned from as small as ~10 nm to ~2 μm and with control over the feature shape and density by changing the deposition parameters. Pattern optimisation, in terms of feature size, density, and contrast, is demonstrated for imaging with atomic force microscopy, scanning electron microscopy, optical profilometry, and optical microscopy. Moreover, the performance of the InSn DIC patterns and their robustness to large deformations is validated in two challenging case studies of in‐situ micromechanical testing: (a) self‐adaptive isogeometric digital height correlation of optical surface height profiles of a coarse, bimodal InSn pattern providing microscopic 3D deformation fields (illustrated for delamination of Al stretchable interconnects on a PI substrate) and (b) DIC on scanning electron microscopy images of a much finer InSn pattern allowing quantification of high strains near fracture locations (illustrated for rupture of a polycrystalline Fe foil). As such, the high controllability, performance, and scalability of the DIC patterns, created by island growth of a solder alloy, offer a promising step towards more routine DIC‐based in‐situ micromechanical testing.  相似文献   

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Functional High‐Tech‐Cellulose materials by the ALCERU® process Cellulose is one of the eldest materials of mankind. While the use of cellulose in former times was focused on application as a more construction or as a more textile material at present time the application profile turns to a more functional material using the ALCERU® process. Shaping of pure cellulose dissolution in NMMNO permits the manufacturing of materials for upholstery, filtration or biodegradable film strips having an uniform cross section. Fibreds, which can be applied in several packaging materials, are available using different techniques for regeneration cellulose. A great field of innovative functional cellulose materials is opened up by addition of several functional additives to cellulose dissolution. In this way piezo‐electrical conductive cellulose fibres (PZT) or high‐temperature filtration membranes are to be generated if one adds special types of ceramic powders. Above all PZT green fibres are applied in more recent uses as sensors or actuators. Electrically conductive cellulose fibres or filaments, which can be also used in the textile chain, can be prepared adding conductive carbon black to a cellulose dope on the same way, too. Cellulose material having adapted conductivity to different application is available by adding an exact defined amount of carbon black to cellulose dissolution. Finally cellulose beads can be manufactured by means of varied shaping technique. The beads are showing variable particle sizes and narrow pore size distribution. These properties open up very interesting application in the field of human blood purification or chromatography.  相似文献   

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A fundamental understanding of structure‐morphology‐property relationships of proton exchange membranes (PEMs) is crucial in order to improve the cost, performance, and durability of PEM fuel cells (PEMFCs). In this context, there has been an explosion over the past five years in the volume of research carried out in the area of non‐perfluorinated, proton‐conducting polymer membranes, with a particular emphasis on exploiting phase behavior associated with block and graft copolymers. This progress report highlights a selection of interesting studies in the area that have appeared since 2005, which illustrate the effects of factors such as acid and water contents and morphology upon proton conduction. It concludes with an outlook on future directions.  相似文献   

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