共查询到20条相似文献,搜索用时 218 毫秒
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碳纳米管具有优异的力学、物理性能,是理想的复合材料增强体.金属/碳纳米管复合材料已成为当今的研究热点.由于碳纳米管易团聚,与基体的相容性差,严重影响了基体和增强体之间的结合.为了增强其相容性,需对碳纳米管表面进行修饰.介绍了碳纳米管表面修饰的方法,综述了国内外的研究现状,展望了碳纳米管表面修饰的发展与应用前景. 相似文献
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KOH活化处理碳纳米管对其负载非晶态NiP催化性能的影响 总被引:1,自引:0,他引:1
经KOH活化处理和未经活化处理的碳纳米管分别用于负载非晶态NiP合金.以苯加氢为探针反应,研究了KOH活化处理温度和时间对碳纳米管的性质及其负载非晶态NiP催化剂活性的影响.研究结果表明:碳纳米管经KOH处理可以提高其负载非晶态NiP催化剂的催化活性,催化剂活性随活化温度升高和活化时间延长而增加.由于KOH处理改变了碳纳米管的微观结构,增加了其比表面积,所以非晶态NiP在碳纳米管上更易沉积分散,其负载的非晶态NiP合金催化剂的催化活性较高. 相似文献
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碳纳米管是由单层或多层石墨片卷曲而成的无缝纳米级管状壳层结构.扼要介绍了碳纳米管、碳纳米管纤维的合成方法及近几年来国内外制备的各种碳纳米管产品.碳纳米管、碳纳米管纤维由于其优良的力学、电学特性可以制成气体吸附体、生物模板、传动装置、增强复合体、催化剂载体、探测器、传感器、纳米反应器等产品,在航空、能源、医药、化学等技术领域广泛应用. 相似文献
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魏芹芹 《功能材料与器件学报》2012,18(1):63-69
随着集成电路的不断发展,电路中互连线规模越来越大,尺寸越来越小,需要承受的电流密度越来越大.在这种趋势下,传统的铜互连线的有效性和可靠性都随之变差.由于碳纳米管具有良好的电学,热学和机械性能,使其成为目前研究较热的互连材料之一.本文概述了碳纳米管用于集成电路互连的优势,碳纳米管互连的电路模型,碳纳米管互连面临的挑战及其... 相似文献
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The article gives a comprehensive overview of hydrogen storage in carbon nanostructures, including experimental results and theoretical calculations. Soon after the discovery of carbon nanotubes in 1991, different research groups succeeded in filling carbon nanotubes with some elements, and, therefore, the question arose of filling carbon nanotubes with hydrogen by possibly using new effects such as nano-capillarity. Subsequently, very promising experiments claiming high hydrogen storage capacities in different carbon nanostructures initiated enormous research activity. Hydrogen storage capacities have been reported that exceed the benchmark for automotive application of 6.5 wt% set by the U.S. Department of Energy. However, the experimental data obtained with different methods for various carbon nanostructures show an extreme scatter. Classical calculations based on physisorption of hydrogen molecules could not explain the high storage capacities measured at ambient temperature, and, assuming chemisorption of hydrogen atoms, hydrogen release requires temperatures too high for technical applications. Up to now, only a few calculations and experiments indicate the possibility of an intermediate binding energy. Recently, serious doubt has arisen in relation to several key experiments, causing considerable controversy. Furthermore, high hydrogen storage capacities measured for carbon nanofibers did not survive cross-checking in different laboratories. Therefore, in light of today's knowledge, it is becoming less likely that at moderate pressures around room temperature carbon nanostructures can store the amount of hydrogen required for automotive applications. 相似文献
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本文概述了碳纳米管的结构性能及制备技术 ,并介绍了目前有关碳纳米材料特别是碳纳米管储氢的理论与实验上的研究进展 相似文献
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To determine if carbon-based materials can be used for hydrogen storage, we have studied hydrogen chemisorption in single-walled carbon nanotubes. Using atomic hydrogen as the hydrogenation agent, we demonstrated that maximal degree of nanotube hydrogenation depends on the nanotube diameter, and for the diameter values around 2.0 nm nanotube-hydrogen complexes with close to 100% hydrogenation exist and are stable at room temperature. This means that specific carbon nanotubes can have a hydrogen storage capacity of more than 7 wt % through the formation of reversible C-H bonds. 相似文献
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Recent advances in the preparation and utilization of carbon nanotubes for hydrogen storage 总被引:1,自引:0,他引:1
Recent progress in the production, purification, and experimental and theoretical investigations of carbon nanotubes for hydrogen storage are reviewed. From the industrial point of view, the chemical vapor deposition process has shown advantages over laser ablation and electric-arc-discharge methods. The ultimate goal in nanotube synthesis should be to gain control over geometrical aspects of nanotubes, such as location and orientation, and the atomic structure of nanotubes, including helicity and diameter. There is currently no effective and simple purification procedure that fulfills all requirements for processing carbon nanotubes. Purification is still the bottleneck for technical applications, especially where large amounts of material are required. Although the alkalimetal-doped carbon nanotubes showed high H2 weight uptake, further investigations indicated that some of this uptake was due to water rather than hydrogen. This discovery indicates a potential source of error in evaluation of the storage capacity of doped carbon nanotubes. Nevertheless, currently available single-wall nanotubes yield a hydrogen uptake value near 4 wt% under moderate pressure and room temperature. A further 50% increase is needed to meet U.S. Department of Energy targets for commercial exploitation. Meeting this target will require combining experimental and theoretical efforts to achieve a full understanding of the adsorption process, so that the uptake can be rationally optimized to commercially attractive levels. Large-scale production and purification of carbon nanotubes and remarkable improvement of H2 storage capacity in carbon nanotubes represent significant technological and theoretical challenges in the years to come. 相似文献
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Hydrogen storage in traditional metallic hydrides can deliver about 1.5 to 2.0 wt pct hydrogen but magnesium hydrides can achieve more than 7 wt pct. However, these systems suffer from high temperature release drawback and chemical instability problems. Recently, big improvements of reducing temperature and increasing kinetics of hydrogenation have been made in nanostructured Mg-based composites. This paper aims to provide an overview of the science and engineering of Mg materials and their nanosized composites with nanostructured carbon for hydrogen storage. The needs in research including preparation of the materials, processing and characterisation and basic mechanisms will be explored. The preliminary experimental results indicated a promising future for chemically stable hydrogen storage using carbon nanotubes modified metal hydrides under lower temperatures. 相似文献
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纳米碳管是一种性能优异的新型功能材料.利用循环失效后的AB5型贮氢合金电极材料作为反应催化剂、乙炔气体作为原料气体通过CVD法制备出多壁纳米碳管,研究了经过破碎、清洗、氧化处理后的失效AB5型贮氢合金电极材料在合成纳米碳管中的催化性能,讨论了不同氧化温度处理催化剂对纳米碳管产率、形貌和结构稳定性的影响.结果表明,氧化处理温度对催化剂的催化效能有明显的影响,600℃为最佳氧化处理温度.以氧化处理后的失效AB5型贮氢合金电极材料作为催化剂制备碳纳米管,方法简单易行,为废旧镍氢电池负极材料的回收再利用提供了一种新的思路. 相似文献
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