Carbon Nanotube clustering

Gabay T, Jakobs E, Ben-Jacob E et al (2005) Engineered self-organisation of neural networks using carbon nanotube clusters. Physica A 350 611-621... 

Carbon nanotube clusters [38] Drug delivery, imaging, thermal ablation... 

The single-wall carbon nanocone-nanohom packing efficiencies, and interaction-energy parameters, are intermediate between those of fullerene and single-wall carbon nanotube clusters. Therefore an in-between behaviour is expected. 

Kim, J.W., Shashkov, E.V., Galanzha, E.L, Kotagiri, N., Zharov, V.P. (2007) Photothermal antimicrobial nanotherapy and nanodiagnostics with self-assembling carbon nanotube clusters. Lasers in Surgery and Medicine 39, 622-34. 

Metal-carbide clusters are relevant to the fonnation of both endohedral fullerenes and carbon nanotubes [1351. There also exists a class of apparently stable metal-carbide cluster ions, = Ti, V, Cr, Zr and Hf), called... 

A cluster of carbon nanotubes that has formed a "rope." The surrounding material below the rope in the photograph consists of fullerenes and other carbon structures. 

An additional and very attractive aspect of molecular qubits is the fact that they are stable in solution, and that the ligand shell can be functionalized with specific chemical groups. In recent years, this has enabled depositing molecular clusters onto different substrates and grafting them to nanostructures or devices, such as carbon nanotube single electron transistors or point contacts [112]. These devices... 

K. Kneipp, A. Jorio, H. Kneipp, S.D.M. Brown, K. Shafer, J. Motz, R. Saito, G. Dresselhaus, and M.S. Dresslhaus, Polarization effects in surface-enhanced resonant Raman scattering of single-wall carbon nanotubes on colloidal silver clusters. Phys. Rev. B 63, 081401.1-081401.4 (2001). 

The various methods of preparation employed to prepare nanoscale clusters include evaporation in inert-gas atmosphere, laser pyrolysis, sputtering techniques, mechanical grinding, plasma techniques and chemical methods (Hadjipanyas Siegel, 1994). In Table 3.5, we list typical materials prepared by inert-gas evaporation, sputtering and chemical methods. Nanoparticles of oxide materials can be prepared by the oxidation of fine metal particles, by spray techniques, by precipitation methods (involving the adjustment of reaction conditions, pH etc) or by the sol-gel method. Nanomaterials based on carbon nanotubes (see Chapter 1) have been prepared. For example, nanorods of metal carbides can be made by the reaction of volatile oxides or halides with the nanotubes (Dai et al., 1995). 

The latter method has been developed to form carbon nanotubes coated with Si02 and oxide clusters of Ni, Cu, Cr or Co [6]. But, in all cases the amount of incorporated guest species is limited to a few weight percents. 

Lourie, O., Wagner, H.D., Evidence of stress transfer and formation of fracture clusters in carbon nanotube-based composites, Comp. Sci. and Techn., 59, 1999, 975-977. 

From a practical point of view, nanotechnology and nanosciences started in the early 1980s. Major developments were the birth of cluster science, the development of the scanning tunneling microscope, the discovery of buck-minsterfullerene (the C60 buckyball) and carbon nanotubes, as well as the synthesis of semiconductor nanocrystals, which led to the development of quantum dots [4]. 

Much research has been devoted to the insertion of different kinds of crystalline and non crystalline material into the hollow interior of carbon nanotubes. The encapsulated species include fullerenes, clusters, one-dimensional (ID) metal nanowires, binary metal halides, metal oxides, and organic molecules. 

Recent advances in theoretical methods and high-performance computing allow for reliable first principle calculations of complex nanostructures. Nanostructured materials are characterized by a fascinating diversity of geometries, but here we restrict ourselves mainly to first-principle calculations for nanoparticles and clusters, nanowires and nanocontacts. Nanoscale multilayers are also discussed very briefly, although multilayers are often considered as a subfield of thin-film physics rather than nanoscience. We also ignore nanotubes, because most of the work in this direction has been done on nonmagnetic carbon nanotubes. 

Astakhova T.Yu., Menon M., Vinogradov G.A. (2003) Three-dimensional solitons in carbon nanotubes. Abstracts of 6th Biennial International Workshop Fullerenes and Atomic clusters (St.-Peterburg), 256. 

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 ... 

Co-MCM-41 catalyst in H2 at temperatures up to 993 K. It is this intermediate species that preserves the tetrahedral environment in the silica framework and provides the resistance to complete reduction to the metal in the presence of H2. The Co(II) species is resistant to reduction in pure CO the intermediate Co(I) species is more reactive in CO, likely forming cobalt carbonyl-like compounds with high mobility in the MCM-41. These mobile species are the precursors of the metal clusters that grow the carbon nanotubes. Controlling the rates of each step of this two-step reduction process is a key to controlling the sizes of the cobalt metal clusters formed in the cobalt MCM-41 catalysts. 

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