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1.
碳纳米管作为一种新型准一维功能材料已成为物理、化学和材料科学等领域的研究热点.由于缺乏微观上的加工处理方法,碳纳米管的应用受到一定程度的限制.磁性纳米材料由于其特殊的物理化学性质在存储器、传感器和环境保护等方面得到了广泛的应用.将磁性纳米粒子与碳纳米管复合不但可以使碳纳米管功能化改性,而且还可通过复合纳米管对磁场的响应对其进行加工处理.综述了碳纳米管与磁性粒子复合的制备技术,并展望了磁性复合碳纳米管的应用及其前景.  相似文献   

2.
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   

3.
郑坤  王必本  侯碧辉 《材料导报》2004,18(Z1):100-102
碳纳米管自Iijima发现以来,由于其独特的结构和性能一直受到人们的关注.目前,已能成功制备出碳纳米管,但沉积条件的改变却导致碳纳米管从中空型结构到竹节型结构变化.综述了竹节型结构碳纳米管形成的机制,并提出了有待进一步研究的问题.  相似文献   

4.
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   

5.
简要介绍了碳纳米管的结构及其分散性,说明碳纳米管具有一维结构及中空的内部结构,极高的化学稳定性,易于团聚.影响碳纳米管分散体系稳定性的关键是空间效应,所以末端亲水基团的结构和性能将明显影响碳纳米管的分散.碳纳米管在基体中的良好分散使复合材料力学性能大幅度提高,并且由于其优良的光电性能,加入碳纳米管也可显著提高复合材料的光电性能和导电性能.此外,碳纳米管石墨层的本质及独特的结构和尺寸,使碳纳米管在提高复合材料的热性能方面也有很大贡献.  相似文献   

6.
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   

7.
着重介绍了碳纳米管近期在仪器分析如色谱、质谱、分子光谱等领域的应用研究进展.由于碳纳米管独特的物理、化学、力学、电学和光学性能,使其在不同仪器分析方法中发挥着重要作用,提高了仪器分离分析检测的灵敏度和选择性.展望了碳纳米管的应用研究前景,指出其对生命科学和药物科学的发展具有较大的意义.  相似文献   

8.
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   

9.
镍磷化学复合镀碳纳米管的摩擦磨损性能研究   总被引:2,自引:0,他引:2  
利用碳纳米管作为增强相制备镍磷基复合镀层,并对其表面形貌和耐摩擦磨损性能进行了测试分析.结果表明,碳纳米管均匀地嵌镶于基体中,且端头露出,覆盖于基体表面;镀层具有优良的耐磨性和自润滑性.这是由于碳纳米管具有较高的强度和一定的自润滑性,加之以网络和缠绕形态分布于基体中,增大了复合相的粘结力,使碳纳米管在磨损时不易拨出而脱落.  相似文献   

10.
碳纳米管自从发现以来,由于其良好的力学、电学、热学以及光学特性,得到很快发展.据美国BCC研究公司分析,2007年全球碳纳米管市场达到7910万美元.这比BCC公司2006年估算的全球市场5090万美元高出55%.  相似文献   

11.
纳米碳管电化学储氢的研究进展   总被引:18,自引:14,他引:4  
纳米碳管的储氢是近年来纳米碳管领域研究的一个热点。纳米碳管储氢研究有两种方法,一种是气相法,另一种是电化学法。本文对纳米碳管电化学储氢的基本原理、纳米碳管电化学储氢的理论计算以及氢与纳米碳管的相互作用机制,特别是目前单壁和多壁纳米碳管电化学储氢的实验研究进展进行了综述,展望了利用其电化学储氢特性作为高性能电池的可能性。  相似文献   

12.
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   

13.
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   

14.
Tersoff—Brenner势函数在纳米碳管研究中的应用   总被引:6,自引:1,他引:5  
介绍一种以键序概念来描述原子间作用的势函数-Tersoff-Brenner势函数表达式和其碳氢系统中的参数化情况,综述了Tersoff-Brenner势函数在单壁纳米碳管的几何结构优化、力学性能、生长机理等理论研究中的应用,并且讨论了这个函数增加长程作用形式,以期能够在单壁在单壁纳米碳管储氢的理论研究中得到应用。  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
分形学体现了科学与美学的完美结合,在众多领域得到了广泛的应用。该文提出了碳纳米管束的分形结构,并将该结构应用于碳纳米管的储氢问题。研究表明,分形碳管束的储氢体积密度高于普通碳管束,并且,通常只需要1级分形结构就可以得到较好的储氢性能。此外,该文通过对不同分形形式的比较,发现内部包含七个碳管的分形结构的储氢性能最优。  相似文献   

20.
纳米碳管是一种新型的纳米材料和碳分子 ,其独特的分子结构和性能引起了人们的广泛关注。纳米碳管的纯化是纳米碳管研究领域的一个重要课题。本文综述了纳米碳管的几种纯化方法及其相关机理。  相似文献   

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