Synthesis of carbon nanotubes with Ni/CNTs catalyst

Solid catalysts are widely used in industrial processes; their catalyses are closely related to not only the active elements but also support materials. The catalytic support plays the role of in-creasing surface area, dispersing active elements, improving heat resistance and mechanical strength. So it is requested that materials used as catalyst support should have excellent mechani-cal properties, enough thermal stability, proper pore structure and large surface area. The com-monly used supp…     

Growth of carbon encapsulated long nickel nanorods on bulk nickel substrate

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 35 nm were tightly encapsulated by the carbon capsules. The detailed formation ...     

碳纳米管复合膜的制备及性能研究

针对膜过滤技术对印染废水中一些含苯环物质难以处理的问题,提出了利用碳纳米管制备新膜材料的方法。分别将碳纳米管(MWNT)和羧基化碳纳米管(c-MWNT)均匀分散在火棉胶溶液中,采用流涎法制备出碳纳米管复合膜;并用分光光度法对样液、滤液中的间苯二酚和茜素红的吸光度进行了对比测定,以考察膜的吸附性能。结果表明:制得的MWNT复合膜分别吸附了13.5%的间苯二酚和42.8%的茜素红;c-MWNT复合膜则分别吸附了33.2%的间苯二酚和80.3%的茜素红,复合膜对间苯二酚和茜素红表现出良好的吸附性,而且制得的复合膜极易再生,可重复使用。     

Decorating multiwalled carbon nanotubes with zinc oxide nanoparticles by thermally decomposing Zn-oleate in an organic medium

Carbon nanotubes decorated with zinc oxide nanoparticles were produced by thermally decomposing a Zn-oleate complex in an octadecene medium. The structure of the ZnO decorating nanotube surfaces was characterized by transmission electron microscopy, scanning electron microscopy and X-ray diffraction. The surfaces were shown to be densely and homogeneously covered by ZnO nanoparticles with a size below 10 nm. The nanoparticles had the wurtzite hexagonal crystal structure and showed good adhesion to the nanotubes. The carbon nanotubes decorated by metal oxide nanoparticles were synthesized at relatively low temperature and non-oxidation environment. Moreover, the large-scale production with low cost can be realized.     

Highly Ordered Carbon Nanotube Arrays with Open Ends Grown in Anodic Alumina Nanoholes

Highly ordered rmdtiwalled carbon nanotube arrays were fabricated by pyrolysis of acetylene within anodic alumina templates. Nanotubes are very uniform irt diameter and open at both ends. High resolution transmission electron microscopy and electron diffraction analysis show that the carbon nanotubes are well graphi-tized. These standing and open carbon nattotubes are possible to offer a potential elegant technique for electron emitting devices, chemical functionalization and nanotube composites.     

碳纳米管储氢的计算机模拟研究

介绍计算机模拟碳纳米管结构和储氢过程.着重介绍了计算机模拟碳纳米管储氢的两种方法,巨正则蒙特卡罗方法和第一原理分子动力学方法,给出了相关的理论依据、关键数据和已经获得的主要实验结果.同时,根据研究过程中发现的问题,对今后这方面的工作提出几点建议.     

甲烷催化裂解制备碳纳米管过程中二氧化碳的影响

生物质发酵沼气含有高浓度CH₄,具有制备碳纳米管的潜力,但其中所含的大量CO₂对碳纳米管制备存在潜在影响. 研究了CH₄催化裂解制备碳纳米管过程中CO₂的影响,使用商用Ni基催化剂和水平管式炉装置开展碳纳米管制备试验,采用TPR、TPO、SEM、TEM等手段对催化剂和碳纳米管进行表征. 650 ℃时催化裂解效率最高,碳产物最大质量为催化剂质量的4倍,其中主要产物为多壁碳纳米管. CO₂对最佳催化裂解温度、催化裂解效率及多壁碳纳米管产量无显著影响,但CO₂的存在增加了碳纳米管内外径、长度和平滑度. 这可能是由于CH₄催化裂解产生无定形积碳,阻碍碳纳米管生长; 而CO₂与积碳反应清除积碳,促进了碳纳米管生长. 从CO₂的影响来看,沼气制备碳纳米管具有可行性.     

碳纳米管振动频率对水合离子团阻塞的影响

为了解决水合离子团的阻塞问题,以碳纳米管进行海水淡化为背景,选取（6,6）扶手椅型碳纳米管作为研究模型,采用分子动力学方法模拟计算碳纳米管的水分子通过性和离子选择性,研究了碳纳米管振动频率对水合离子团的阻塞作用。研究结果表明：通过施加外力使碳纳米管发生周期性振动,可有效改善水合离子团对碳纳米管的阻塞;不同的振动频率对水分子通过碳纳米管的速率有不同影响,且得出了最恰当的频率。     

新型三维（3,3）碳纳米管聚合体

本文研究了单壁（3,3）碳纳米管束在高压下的结构演变过程。在静水压40 GPa下,（3,3）碳纳米管束会直接聚合形成一种新型六方三维碳纳米管聚合体（命名为六方3D-（3,3）碳）。卸除压力后,它能保持其结构不变,成为一种新型半导体性的超硬碳。该研究为压缩碳纳米管合成新型碳提供了理论依据。     

碳纳米管表面羟基化及其纳米流体的导热性能研究

采用强碱机械球磨技术对碳纳米管进行表面功能化。红外光谱和Zeta电位测试结果表明,处理后的碳纳米管表面已被羟基化;扫描电镜结果表明,处理后的碳纳米管已被截断短化。表面功能化并被截断短化的碳纳米管能够均匀稳定地分散在水中,得到的水基含碳纳米管纳米流体具有良好的传热性能。当碳纳米管体积分数为1．0％时,与水相比它的导热系数提高达17．5％。由于纳米粒子的润滑作用,在碳纳米管体积分数较低（Ф〈0．004）的情况下,含碳纳米管纳米流体的粘度要比基体流体水的粘度低;当碳纳米管的体积分数高于0．004时,含碳纳米管纳米流体粘度随着碳纳米管含量的增加而升高。     

Energy absorption characteristics of single-walled carbon nanotubes

The excellent mechanical properties of carbon nanotubes make them potential candidates for engineering application. In this paper, the impact and failure behaviors of single-walled carbon nanotubes (SWCNTs) are investigated. The effects of diameter, length, and chirality on their energy absorption characteristics under lateral impact and axial crush are studied. By integrating the principle of molecular structural mechanics (MSM) into finite element method (FEM), the locations and directions of fracture process can be predicted. It is shown that the specific energy absorption (SEA) of SWCNTs is 1–2 order of magnitude higher than that of the ordinary metallic materials and composites in axial impact, indicating that carbon nanotubes are promising energy absorption materials for engineering applications.     

Development of supercapacitors based on carbon nanotubes

Block-type electrodes made of carbon nanotubes were fabricated by different processes. The volumetric specific capacitance based on such electrodes reached 107 F/cm3, which proves carbon nanotubes to be ideal candidate materials for supercapacitors. The composite electrodes consisting of carbon nanotubes and RuO2 ·xH2O were developed by the deposition of RuO2 on the surface of carbon nanotubes. Supercapacitors based on the composite electrodes show much higher specific capacitance than those based on pure carbon nanotube ones. A specific capacitance of 600 F/g can be achieved when the weight percent of RuO2· xH2O in the composite electrodes reaches 75% . In addition , supercapacitors based on the composite electrodes show both high energy density and high power density characteristics.     

碳纳米管的力学特性及其在改善水泥基材料性能中的应用

通过理论分析和数值模拟研究了碳纳米管的力学性能参数和其在轴向压缩以及弯曲荷载作用下的屈曲行为,并进行了用碳纳米管提高水泥基复合材料强度和韧性等力学性能的实验.结果表明:当好的分散效果被获得后,水泥基复合材料的强度和韧性可以得到明显的改善,而碳纳米管容易发生屈曲的特性是影响其作为理想增强材料的一个内在原因.     

碳纳米管在生物医学传感器中的应用

从碳纳米管结构、电学性质及碳纳米管修饰电极出发,综述了碳纳米管在生物医学压力传感器、生物医学气体传感器、生物医学葡萄糖传感器中的应用,并对碳纳米管在生物医学传感器领域中的进一步应用需要解决的问题进行了概括.     

碳纳米管在生物医学传感器中的应用

从碳纳米管结构、电学性质及碳纳米管修饰电极出发，综述了碳纳米管在生物医学压力传感器、生物医学气体传感器、生物医学葡萄糖传感器中的应用，并对碳纳米管在生物医学传感器领域中的进一步应用需要解决的问题进行了概括．     

多壁纳米碳管中的AAS效应研究

分析研究了多壁纳米碳管中的AAS效应．通过给出多壁纳米碳管中电子的多圈(通道)分波波函数的量子干涉模型，在AAS理论的框架下推出了多壁纳米碳管磁电阻的解析表达式．研究还发现由于多壁纳米碳管壁间的相互作用，多壁纳米碳管中电子的输运性质是扩散型的，存在着一个确定的相位相干长度．有限的相位相干长度用在磁电阻公式中可以解释最新的几个多壁纳米碳管中的磁电阻实验，如典型的负磁阻效应、磁电阻随外加磁场的高阶周期震荡等．     

直径对单壁碳纳米管热力学性质影响的理论研究

采用MedeA软件包优化了一系列不同直径的碳纳米管的结构,并计算了相关声子谱和声子态密度,进一步计算了碳纳米管的热力学性质。结果表明碳纳米管的直径和温度对其热力学性质有影响。碳纳米管的直径越大,其生成能和总能量就越低,即稳定性越好。在低温时,直径对碳纳米管的热力学性质的影响较小;高温时,碳纳米管的热力学性质Cv(T)、S0(T)、–A(T)及Evib(T)随直径增大呈现升高趋势,而E(T)和G(T)则随碳纳米管的直径增大呈现降低趋势。     

碳纳米管的场致发射研究进展

碳纳米管的研制和应用是一门新兴的科学技术。碳纳米管薄膜机械强度高，化学稳定性好，并且有很低的发射场强阀值，较高的发射电流密度。碳纳米管阵列薄膜的这些特显示出其在场致发射应用中的良好前景。介绍了碳纳米管的几种产生工艺、碳纳米管在场致发射方面的研究和应用场景新动态，比较了不同生产工艺的优缺点及场致发射的特性，分析了碳纳米管用于场致发射存在的不足和发展前景。     

碳纳米管的制备与应用研究进展

简述了碳纳米管的结构与性能,详细介绍了碳纳米管常见的制备方法和原理,以及碳纳米管在各个领域的应用和研究进展.     

功能化单壁碳纳米管的气敏性研究

通过不同官能团功能化,在单壁碳纳米管(SWNTs)上连接不同基团并制成薄膜。采用恒定电位法,将它们暴露在NO2中,N2作为载气,不同温度下(30℃、50℃、70℃、90℃)检测电流随时间的变化情况(I-t图)。结果表明,随着温度的升高各薄膜对NO2的响应速率加快;含对苯基的SWNTs薄膜在50℃灵敏度最大,而连接有羧基、氨基的SWNTs薄膜在30℃灵敏度最大;对硝基苯基功能化后的SWNTs对NO2的响应程度最大,明显强于其他薄膜。