Amorphous carbon nanotubes

Schittenhelm, H., Geohegan, D. B. and Jellison, G. E., Synthesis and characterization of single-wall carbon nanotube-amorphous diamoid thin-film composites. Applied Physics Letters, 81,2001,2097-2099. 

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... 

Various forms of carbon material such as graphite, diamond, carbon nanotubes (fibers), and amorphous carbon-containing, diamond-like carbon have been compared and analyzed for their potential application in the fields of flat panel displays and lighting elements.48... 

The aluminum is incorporated in a tetrahedral way into the mesoporous structure, given place to Bronsted acidic sites which are corroborated by FTIR using pyridine as probe molecule. The presence of aluminum reduces the quantity of amorphous carbon produced in the synthesis of carbon nanotubes which does not happen for mesoporous silica impregnated only with iron. It was observed a decrease in thermal stability of MWCNTs due to the presence of more metal particles which help to their earlier oxidation process. 

This chapter describes the storage of hydrogen in several forms of carbon, ranging from amorphous activated carbon (AC) to the ordered forms such as graphite and carbon nanotubes (CNTs). Carbon materials can be utilized for hydrogen storage in the following different ways ... 

Biercuk MJ, Llaguno MC, Radosavljevic M, Hyun JK, Johnson AT (2002). Morphological and mechanical properties of carbon-nanotube-reinforced semicrystalline and amorphous polymer composites. Appl. Phys. Lett. 80 2767-2769. 

Nanocarbon hybrids have recently been introduced as a new class of multifunctional composite materials [18]. In these hybrids, the nanocarbon is coated by a polymer or by the inorganic material in the form of a thin amorphous, polycrystalline or single-crystalline film. The close proximity and similar size domain/volume fraction of the two phases within a nanocarbon hybrid introduce the interface as a powerful new parameter. Interfacial processes such as charge and energy transfer create synergistic effects that improve the properties of the individual components and even create new properties [19]. We recently developed a simple dry wrapping method to fabricate a special class of nanocarbon hybrid, W03 /carbon nanotube (CNT) coaxial cable structure (Fig. 17.2), in which W03 layers act as an electrochromic component while aligned... 

Carbon nanotubes, as graphene and graphite, are highly ordered carbon phases. However, a separate line can be drawn for historical development of disordered carbon phases among them is an amorphous carbon (am-C). In it, strong bonding between carbons did not allow for completely chaotic distribution of carbon atoms in solid-state phase. Instead, amorphous carbon exhibits random distribution of three possible coordinations of carbon atoms in a planar sp, tetrahedral sp and... 

Amorphous carbon, graphite, fullerene and carbon nanotubes (CNT)... 

As reported elsewhere [22], similar to those found on other catalysts, the forms of carbon materials deposited on Fe-loading zeolite molecular sieves are carbon nanotube, carbon nanofiber and amorphous carbon. One obvious phenomenon of the carbon nanotubes formed on Fe/NaY or Fe/SiHMS catalysts is that almost all tips of these tubes are open, indicating the interaction between catalyst particles and supports is strong [23]. On the other hand, the optimal formation time of carbon nanotubes on Fe/SiHMS is longer than that on Fe/NaY. However, the size of carbon nanotubes is easily adjusted and the growth direction of carbon nanotubes on the former is more oriented than on the latter. 

Mass-spectrometer date of the hydrogenated carbon nanotubes we have published in (Shulga et al. 2004). These nanotubes for the gas mass-spectrometry were synthesized by the electric-arc method using a nickel-yttrium catalyst. To remove amorphous carbon and the metal catalyst, the primary products containing 10-15 wt% of carbon SWNTs were purified by repeated oxidation in air at temperatures... 

Although a lot of research has been reported on the use of various carbonaceous materials in defluoridation, no known column or full-scale plant operation is easily available in open literature. One reason for this is that most carbonaceous materials show poor adsorption capacity (Table 4) for fluoride and therefore only laboratory-scale performances have so far been reported. Amorphous alumina supported on carbon nanotubes on the other hand show high capacity (28.7 mgF/g adsorbent) for fluoride and is therefore a promising material for drinking water defluoridation. 

Amorphous carbon is a general term that covers non-crystalline forms of carbon such as coal, coke, charcoal, carbon black (soot), activated carbon, vitreous carbon, glassy carbon, carbon fiber, carbon nanotubes, and carbon onions, which are important materials and widely used in industry. The arrangements of the carbon atoms in amorphous carbon are different from those in diamond, graphite, and fullerenes, but the bond types of carbon atoms are the same as in these three crystalline allotropes. Most forms of amorphous carbon consist of graphite scraps in irregularly packing. 

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