Carbon Nanotube and Gold‐Based Materials: A Symbiosis

Carbon nanotubes constitute a novel class of nanomaterials with potential applications in many areas. The attachment of metal nanoparticles to carbon nanotubes is new way to obtain novel hybrid materials with interesting properties for various applications such as catalysts and gas sensors as well as electronic and magnetic devices. Their unique properties such as excellent electronic properties, a good chemical stability, and a large surface area make carbon nanotubes very useful as a support for gold nanoparticles in many potential applications, ranging from advanced catalytic systems through very sensitive electrochemical sensors and biosensors to highly efficient fuel cells. Here we give an overview on the recent progress in this area by exploring the various synthesis approaches and types of assemblies, in which nanotubes can be decorated with gold nanoparticles and explore the diverse applications of the resulting composites.     

碳纳米管/壳聚糖复合材料

碳纳米管/壳聚糖复合材料是一种具有生物和光电双重功能的复合材料。本文在对碳纳米管和壳聚糖各种性质进行简单介绍的基础上,重点综述了碳纳米管与壳聚糖复合材料的各种复合方法、机理、主要应用以及存在的主要问题。     

碳纳米管在生物化学传感及生物传输方面的应用

碳纳米管作为一种新型一维纳米材料具有独特的结构和性质,在生物传感、生物标记及生物传榆等研究中显示了巨大的潜力.碳纳米管在化学、生物及医药方面的研究应用具有重要的理论意义及实际意义.重点综述了碳纳米管在生物化学传感和生物传榆中的研究应用进展,并展望了其发展趋势和应用前景.     

碳纳米管的纯化

目前制备碳纳米管的方法很多，然而这些方法所制得的产物中除碳纳米管外常常还含有无定形碳、碳纳米粒子及催化剂颗粒等杂质，这些杂质的存在直接影响到碳纳米管的性能测试及其应用研究，因此碳纳米管的纯化研究十分必要与重要。而不同制备方法所得碳纳米管的性质以及所引入的杂质都不相同，这就增加了碳纳米管纯化研究的难度。本文结合该领域研究前沿对碳纳米管的纯化机理及方法做了系统的介绍。     

Electrochemical Sensors Based on Carbon Nanotubes

Carbon nanotubes are attractive new materials. It has been about a decade since carbon nanotubes were discovered. Carbon nanotubes have many outstanding properties and have many practical or potential applications. In this short review we introduce recent advances in carbon nanotubes as potential material for electrochemical sensors. The advantages of carbon nanotubes as sensors are discussed along with future prospects.     

Dispersions, novel nanomaterial sensors and nanoconjugates based on carbon nanotubes

Nanomaterials are structures with dimensions characteristically much below 100 nm. The unique physical properties (e.g., conductivity, reactivity) have placed these nanomaterials in the forefront of emerging technologies. Significant enhancement of optical, mechanical, electrical, structural, and magnetic properties are commonly found through the use of novel nanomaterials. One of the most exciting classes of nanomaterials is represented by the carbon nanotubes. Carbon nanotubes, including single-wall carbon nanotubes, multi-wall carbon nanotubes, and concentric tubes have been shown to possess superior electronic, thermal, and mechanical properties to be attractive for a wide range of potential applications They sometimes bunch to form “ropes” and show great potential for use as highly sensitive electronic (bio)sensors due to the very small diameter, directly comparable to the size of single analyte molecules and that every single carbon atom is in direct contact with the environment, allowing optimal interaction with nearby molecules. Composite materials based on integration of carbon nanotubes and some other materials to possess properties of the individual components with a synergistic effect have gained growing interest. Materials for such purposes include conducting polymers, redox mediators and metal nanoparticles. These tubes provide the necessary building blocks for electronic circuits and afford new opportunities for chip miniaturization, which can dramatically improve the scaling prospects for the semiconductor technologies and the fabrication of devices, including field-effect transistors and sensors. Carbon nanotubes are one of the ideal materials for the preparation of nanoelectronic devices and nanosensors due to the unique electrical properties, outstanding electrocatalytic properties, high chemical stability and larger specific surface area of nanotubes. Carbon nanotubes are attractive material for supercapacitors due to their unique one-dimensional mesoporous structure, high specific surface area, low resistivity and good chemical stability. Nanoscaled composite materials based on carbon nanotubes have been broadly used due to their high chemical inertness, non-swelling effect, high purity and rigidity. The integration of carbon nanotubes with organics, biomaterials and metal nanoparticles has led to the development of new hybrid materials and sensors. Hybrid nanoscale materials are well established in various processes such as organic and inorganic compounds, nucleic acid detachment, protein separation, and immobilization of enzymes. Those nanostructures can be used as the building blocks for electronics and nanodevices because uniform organic and metal coatings with the small and monodisperse domain sizes are crucial to optimize nanoparticle conductivity and to detect changes in conductivity and absorption induced by analyte adsorption on these surfaces. The highly ordered assembly of zero-dimensional and one-dimensional nanoparticles is not only necessary for making functional devices, but also presents an opportunity to develop novel collective properties.     

碳纳米管在电化学和光化学纳米生物传感器中的应用

碳纳米管(CNTs)因具有独特的物理化学及电化学性质,如较大的比表面积、较强的电子转移能力和良好的吸附性能等而引起人们的广泛关注.碳纳米管可以通过物理吸附、静电或疏水作用等非共价结合方式或共价连接方式固定生物大分子(如蛋白质、DNA、抗体等),有效地促进生物大分子与电极间直接、快速的电子转移,可应用于多种电化学生物传感器中.碳纳米管本身在近红外光区具有独特的荧光和拉曼光谱,可以利用多种光谱手段对多种生物分子实现定量检测,因此近年来碳纳米管在光化学生物传感器中的应用也逐渐受到了研究者的重视.本文对碳纳米管在电化学和光化学生物传感器中的应用进行了简要综述和展望.     

π-Concave Hosts for Curved Carbon Nanomaterials

Carbon nanomaterials have been at the forefront of nanotechnology since its inception. At the heart of this research are the curved carbon nanomaterial families: fullerenes and carbon nanotubes. While both have incredible properties that have been capitalized upon in a wide variety of applications, there is an aspect that is not commonly exploited by nanoscientists and organic chemists alike: the interaction of curved carbon nanomaterials with curved organic small molecules. By taking advantage of these interactions, new avenues are opened for the use of fullerenes and carbon nanotubes.     

Sorption behavior of acidic herbicides on carbon nanotubes

Carbon nanotubes and graphitized carbon are investigated as adsorbents for solid phase extraction of dicamba and 2,4,5-T, two phenoxyalkanoic acid herbicides. These adsorbents have much greater adsorption capability than that of C₁₈ bonded silica, which was also tested for comparison studies. The adsorption capacity increases remarkably at lower pH of the sample solution. Freundlich isotherms were applied to analyze the data. Our studies suggest that carbon nanotubes have great potential applications in environmental analysis.     

不同结构碳纳米管的电磁波吸收性能研究

研究了单壁、多壁碳纳米管(聚团状、阵列状)以及未纯化与纯化后碳纳米管在2～18 GHz范围内的电磁波吸收性能. 通过测定不同结构碳纳米管粉体的介电常数以及磁导率, 得到损耗因子及衰减常数大小顺序为: 阵列状多壁碳纳米管>原生聚团状多壁碳纳米管>纯化聚团状多壁碳纳米管>原生单壁碳纳米管>纯化后单壁碳纳米管. 相比多壁碳纳米管, 单壁碳纳米管衰减常数随频率变化较小, 且具有较宽的吸收峰. 模拟计算和实验测试结果都表明, 碳纳米管/聚合物复合材料具有优良的电磁吸波性能.     

碳纳米管在电分析中的应用

碳纳米管因其独特的特性,自发现以来得到了广泛的关注与应用;本文着重对碳纳米管在电分析中的应用作了综述。     

取向碳纳米管制备方法及其应用进展*

碳纳米管有广阔的应用前景,但很多应用是以碳纳米管定向的取向排列为前提.本文全面介绍了制备取向碳纳米管的各种方法和研究进展,综合阐述了各种制备方法的特点,并初步讨论了制备取向生长碳纳米管各种方法的机理.最后,对取向碳纳米管的应用进行了展望,提出了碳纳米管应用的新思路.     

碳纳米管的定向操作

由于呈现独特的一维结构特征、机械及电子性能,碳纳米管已引起广泛的兴趣,然而涉及到具体的应用就不可避免碳纳米管的定位、定向,这也已成为非常富有挑战性的课题。本文中笔者主要介绍碳纳米管定向操作的最新进展,重点介绍后生长的平面有序定向操作。     

Dental Applications of Carbon Nanotubes

Glass ionomer cements and resin-based composites are promising materials in restorative dentistry. However, their limited mechanical properties and the risk of bulk/marginal fracture compromise their lifespan. Intensive research has been conducted to understand and develop new materials that can mimic the functional behavior of the oral cavity. Nanotechnological approaches have emerged to treat oral infections and become a part of scaffolds for tissue regeneration. Carbon nanotubes are promising materials to create multifunctional platforms for dental applications. This review provides a comprehensive survey of and information on the status of this state-of-the-art technology and describes the development of glass ionomers reinforced with carbon nanotubes possessing improved mechanical properties. The applications of carbon nanotubes in drug delivery and tissue engineering for healing infections and lesions of the oral cavity are also described. The review concludes with a summary of the current status and presents a vision of future applications of carbon nanotubes in the practice of dentistry.     

碳纳米管共价功能化

碳纳米管由于其独特的结构与优异的各项性能,在许多领域具有巨大的应用潜力,已引起了广泛的关注。由于碳纳米管不溶于水和有机溶剂,极大地制约了其性能应用,因此碳纳米管的功能化就成为目前研究的热点。本文侧重于碳纳米管的共价功能化,详细讨论了碳纳米管不同位置共价功能化的研究进展。     

Carbon nanotube gas and vapor sensors

Carbon nanotubes have aroused great interest since their discovery in 1991. Because of the vast potential of these materials, researchers from diverse disciplines have come together to further develop our understanding of the fundamental properties governing their electronic structure and susceptibility towards chemical reaction. Carbon nanotubes show extreme sensitivity towards changes in their local chemical environment that stems from the susceptibility of their electronic structure to interacting molecules. This chemical sensitivity has made them ideal candidates for incorporation into the design of chemical sensors. Towards this end, carbon nanotubes have made impressive strides in sensitivity and chemical selectivity to a diverse array of chemical species. Despite the lengthy list of accomplishments, several key challenges must be addressed before carbon nanotubes are capable of competing with state-of-the-art solid-state sensor materials. The development of carbon nanotube based sensors is still in its infancy, but continued progress may lead to their integration into commercially viable sensors of unrivalled sensitivity and vanishingly small dimensions.     

Lattice specific heat of carbon nanotubes

The lattice specific heat in carbon nanotubes is evaluated within the microscopic model proposed by Mahan and Jeon, published in the Physical Review B, in 2004. Phonons are considered for single wall carbon nanotubes in armchair configuration. As expected, low temperature and high temperature regions show different behaviour of specific heat. Carbon nanotubes are also displaying a very interesting lattice transport depending on the tube diameter, with high thermal conductivities for small diameters.     

para‐Connected Cyclophenylenes and Hemispherical Polyarenes: Building Blocks for Single‐Walled Carbon Nanotubes?

Carbon nanotubes by design? Cyclo-para-phenylenes are monomers for the synthesis of armchair carbon nanotubes (see picture, right), and are also attractive fluorophores that display size-dependent emission properties. Geodesic polyarenes represent a realistic alternative for the rational design of carbon nanotubes through the chemical elongation of the hydrocarbon template (left).     

Electrochemical Biosensing Systems Based on Carbon Nanotubes and Carbon Nanofibers

Abstract

Carbon nanomaterials are in the forefront of research in a variety of chemical and physical disciplines. Of these, certain nanostructures seem to be suitable for the development of electrochemical biosensors. In particular carbon nanotubes, and carbon nanofibers have specific chemical and physical characteristics that lent them ideal for the development of biosensors with unique analytical characteristics. In particular, their conductivity, surface area, inherent and induced chemical functionalities, and biocompatibility provide the grounds for the development of a new era of electrochemical biosensors. In this review, we will examine the recent developments of biosensor design based on these new nanostructures.     

3,4,9,10-Perylene Tetracarboxylic Acid Noncovalently Modified Multiwalled Carbon Nanotubes: Synthesis,Characterization, and Application for Electrochemical Determination of 2-Aminonaphthalene

Carbon nanotubes have been intensively studied for their diverse applications but are insoluble in water. In this paper, 3,4,9,10-perylene tetracarboxylic acid noncovalently modified multiwalled carbon nanotubes were prepared by a facile approach and applied successfully for electrochemical determination of 2-aminonaphthalene. Infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and electrochemical methods were used to characterize the hybridized nanotubes. The results reveal that the hybrids exhibit high dispersibility in water, and a glassy carbon electrode modified by the hybrids displayed a higher electrochemical response toward 2-aminonaphthalene than bare glassy carbon and multiwalled carbon nanotube–glassy carbon electrodes with a linear dynamic range of 15.0–500.0 nM and a detection limit of 4.5 nM. The modified hybrid electrode was successfully applied for the determination of 2-aminonaphthalene in water.