Carbon-based nanotubes

Carbon-based nanotubes (CNTs) have attracted a great deal of attention in the fields of chemistry, physics, and materials science and have been extensively studied since their initial discovery in 1991.36 Much of the excitement in this area of research stems from their unique structures, fundamental electronic and physical properties, and potential applications.37 Inspired by these carbon nanotube studies, coordination chemists have undertaken significant efforts toward the construction of tube-like complexes through metal-ligand coordination.38 1 Examples of silver(I) tubular complexes obtained via assembly reactions of predesigned organic ligands with silver salts are described here.42-44... 

Fig. 10. The proposed structure of the SET-hased readout circuit for THz detector. The quantum detector cell (QDC), which is the triple Q-dot system, is capacitively coupled through the sense electrode to a carbon based nanotubes RF-SET. A bias-electrode is used to control the bias potential on the sense electrode.

As mentioned in the introduction, the tubular materials are fascinating new structures with a considerable potential for various applications. Most of the nanotubes investigated to date have been carbon-based nanotubes. In this chapter, we have discussed the properties of various nanotubes with a silicon or germanium backbone structure. Most of these nanotubes are still hypothetical, "made" only in the computer. We proposed the stability of phosphorus nanotubes, and about a year later Li et al. reported the successful synthesis of nanotubes from bismuth, which is isoelectronic with phosphorus. The stability of NbS2 nanotubes was also proposed in 2000, and these were synthesized by Nath and Rao in 2001... 

Stability of Carbon-Based Nanotubes and Nanoflbers References... 

As further research on fullerenes and carbon nanotubes materials is carried out, it is expected, because of the extreme properties exhibited by these carbon-based materials, that other interesting physics and chemistry will be discovered, and that promising applications will be found for fullerenes, carbon nanotubes and related materials. 

Chapter 1 contains a review of carbon materials, and emphasizes the stmeture and chemical bonding in the various forms of carbon, including the foui" allotropes diamond, graphite, carbynes, and the fullerenes. In addition, amorphous carbon and diamond fihns, carbon nanoparticles, and engineered carbons are discussed. The most recently discovered allotrope of carbon, i.e., the fullerenes, along with carbon nanotubes, are more fully discussed in Chapter 2, where their structure-property relations are reviewed in the context of advanced technologies for carbon based materials. The synthesis, structure, and properties of the fullerenes and... 

The goal of this book is thus to assess progress in the field, to identify fruitful new research directions, to summarize the substantial progress that has thus far been made with theoretical studies, and to clarify some unusual features of carbon-based materials that are relevant to the interpretation of experiments on carbon nanotubes that are now being so actively pursued. A second goal of this book is thus to stimulate further progress in research on carbon nanotubes and related materials. 

The carbon-based nanofillers are mainly layered graphite, nanotube, and nanofibers. Graphite is an allotrope of carbon, the stmcture of which consists of graphene layers stacked along the c-axis in a staggered array [1], Figure 4.1 shows the layered structure of graphite flakes. 

Nanotubes, a new class of carbon-based materials with strength roughly one hundred times that of steel, also have an exceptional toughness. 

In conclusion, such three-dimensional carbon-based nanostructures as fullerenes and nanotubes constitute scaffolds whose efficient functionalization and derivatization... 

CNTs have been one of the most actively studied electrode materials in the past few years due to their unique electronic and mechanical properties. From a chemistry point of view, CNTs are expected to exhibit inherent electrochemical properties similar to other carbon electrodes widely used in various electrochemical applications. Unlike other carbon-based nanomaterials such as C60 and C70 [31], CNTs show very different electrochemical properties. The subtle electronic properties suggest that carbon nanotubes will have the ability to mediate electron transfer reactions with electroactive species in solution when used as the electrode material. Up to now, carbon nanotube-based electrodes have been widely used in electrochemical sensing [32-35], CNT-modified electrodes show many advantages which are described in the following paragraphs. 

The structure-property relations of fullerenes, fullerene-derived solids, and carbon nanotubes are reviewed in the context of advanced technologies for carbon-based materials. The synthesis, structure and electronic properties of fullerene solids are then considered, and modifications to their structure and properties through doping with various charge transfer agents are reviewed. Brief comments are included on potential applications of this unique family of new materials. 

While this recent study produced more comforting research results, it is in no way the end of the story on how nanoproduct pollution could impact the environment and life. Scientists continue to study the effects of carbon-based buckyballs and nanotubes, plus other nanotechnology creations that do not contain carbon. 

The development of new porous materials that could be used as adsorbents, catalysts, catalyst supports, molecular sieves, etc. [1], are very well discussed by several authors [2-9], describing interesting properties and characteristics of materials such as MCM-41, MCM-48, M41S, FSM16, lamellar phases, intercalation products, special CMS (carbon molecular sieves), fullerenes, carbon nanotubes, etc. being some of them silica based materials, and carbon based the others. 

On the other hand, forty years ago a lot of properties of carbon based materials coming from pyrolytic processes were well known [10-14] but it was in the last years where new kinds of CMS, fullerenes and carbon nanotubes [15-17] were discovered and studied These materials have the limitation of their small open pore size, which in general is near 10 A diameter, and then, diffusional and esteric problems may be present when they must interact with molecules of equal or bigger size within the mentioned pore diameter. 

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