Metallic nanotube

Hu, X., et ah, A general route to prepare one- and three-dimensional carbon nanotube/metal nanoparticle composite nanostructures, hangmuir, 2007. 23(11) p. 6352-6357. 

Flahaut, E., Peigney, A., Laurent, C. et al., Carbon nanotube-metal-oxide nanocomposites microstructure, electrical conductivity and mechanical properties, Acta Mater., 2000, 48 3803. 

Jiang, L. and Gao, L., Carbon nanotubes-metal nitride composites a new class of nanocomposites with enhanced electrical properties , J. Mater. Chem., 2005, 15(2), 260-266. 

Peigney, A., Rul, S., Lefevre-Schlick, F. and Laurent, Ch., Densification during hot-pressing of carbon nanotube-metal-magnesium aluminate spinel composites , to be submitted, 2006. 

Many materials exist that have dimensions in the range of 1 rnn to several micrometers. Recall that colloidal particles (e.g., latex particles from emulsion polymerization, colloidal silica or alumina, etc.) fall in the range from about 10 nm to 1000 nm (1 jxm). A few examples of nanoparticles that are designed with more specific structures or geometries include carbon nanotubes, metal clusters, nanoscale magnetic crystals, and semiconducting ... 

Guo S, Dong S, Wang E (2008) Constructing carbon-nanotube/metal hybrid nanostructures using homogeneous Ti02 as a spacer. Small 4 1133-1138... 

Nanomaterials, carbon nanotubes, metal nanoparticles/adsorp-tion, electro- and photopolymerization... 

Keywords sol-gel process, nanotubes, metal-doped silica gel... 

Heben, M.J., Dillon, A.C., Gilbert, K.E.H., et al. (2002). Assessing the hydrogen adsorption capacity of single-waU carbon nanotube/metal composites. In Hydrogen in Materials and Vacuum Systems First International Workshop on Hydrogen in Materials and Vacuum Systems, American Institute of Physics, 671, 77 (G.R. Myneni and S. Chattopadhyay, eds). 

The addition of dichlorocarbenes also allows for further conversions as the existing substituents can be replaced. Normally, PhHgCCbBr is used as carbene source in this reaction, but it succeeds with other carbenes or carbene sources as well. The addition of dichlorocarbene markedly changes the electronic structure of the functionahzed nanotube. Metallic SWNT, for instance, turn into semiconductors, which is due to altered electronic transitions close to the Fermi level. What is more, the intensity of interband transitions decreases for both the original metalHc and the semiconducting species because the extended n-network is severely disturbed by the functionalization and the concomitant introduction of sp -carbon atoms. However, a completely different picture of the carbene or nitrene addition is... 

Up to now, most of our discussion featured small molecules, complexes, or clusters. In this section, we examine on how these conclusions could be extended to the realm of functional assemblies and nanomaterials. We begin with examining the structures and physical characteristics of carbon containing systems. We then progress to a discussion of organic nanotubes, metallic and encapsulated nanowires, and finally, nanodevices. 

CNTs can be combined with various metal oxides for the degradation of some organic pollutants too. Carbon nanotubes/metal oxide (CNT/MO) composites can be prepared by various methods such as wet chemical, sol gel, physical and mechanical methods. To form nanocomposite, CNTs can be combined with various metal oxides like Ti Oj, ZnO, WO3, Fc203, and AI2O3. The produced nanocomposite can be used for the removal of various pollutants. Nanoscale Pd/Fe particles were combined with MWNTs and the resulted composite was used to remove 2,4-dichlorophenol (2,4-DCP). It was reported that the MB adsorption was pH-dependent and adsorption kinetics was best described by the pseudo-second-order model. Iron oxide/CNT composite was reported to be efficient adsorbent for remediation of chlorinated hydrocarbons. The efficiency of some other nanocomposites such as CNT/ alumina, CNT/titania and CNT/ZnO has also been reported [60-62]. 

Kauffman, D. R. and Star, A. (2007), Chemically induced potential barriers at the carbon nanotube-metal nanoparticle interface , Auno Letters, , 1863-8. 

Key words carbon nanotubes/metal oxides gas sensor, MOX/CNT composites, p-n heterojunctions, hybrid sensor, sensing part for e-nose. 

Preparation of carbon nanotube-metal oxide sensing fiims... 

Nanofillers have superb thermal and electrical properties. All nanotubes are expected to be very good thermal conductors along the tube axis, exhibiting a property known as ballistic conduction, but good insulators laterally to the tube axis. It has been reported that single-wall carbon nanotubes exhibit thermal conductivity (TC) values as high as 2000-6000 W mK [4] under ideal circumstances. The temperature stability of carbon nanotubes is estimated to be up to 2800 °C in a vacuum, and about 750 °C in air. By comparison, metals have TC values of several hundred W mK , and water and oil have TC values of only 0.6 W mK and 0.2 W mK respectively. Table 19.1 lists the thermal conductivities of various materials, including nanofillers (nanotubes), metals, and oils. 

Metal matrix nanocomposites are those having metal as the continuous phase or matrix and other nanoparticles like carbon nanotube as the reinforced materials. These types of composites can be classified as continuous and noncontinuous. One of the more important nanocomposites is Carbon nanotube reinforced metal matrix composite, which is an emerging new material with the high tensile strength and electrical conductivity of carbon nanotube materials. In addition to carbon nanotube metal matrix composites, boron nitride reinforced metal matrix composites and carbon nitride metal matrix composites are the new research areas on metal matrix nanocomposites [9,10]. 

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