Carbon nanotubule

Abstract—Carbon nanotubules were produced in a large amount by catalytic decomposition of acetylene in the presence of various supported transition metal catalysts. The influence of different parameters such as the nature of the support, the size of active metal particles and the reaction conditions on the formation of nanotubules was studied. The process was optimized towards the production of nanotubules having the same diameters as the fullerene tubules obtained from the arc-discharge method. The separation of tubules from the substrate, their purification and opening were also investigated. 

Fig. 9. Carbon nanotubules on Co-Si02 (a) HREM image showing defects in tubules (b) helical tubules of various pitches between the straight tubules.

Fig. 10. H NMR spectra (a) coronene (b) Co-SiOj covered by carbon nanotubulcs (c) Co-SiOj covered by carbon nanotubules and evacuated to 10 torr for the NMR measurement (d) Co-SiO evacuated to 10 torr for the NMR measurement.

Fig. 12. Carbon nanotubules after separation from the substrate by ultra-sound treatment. Note the Si02...

Carbon nanotube research was greatly stimulated by the initial report of observation of carbon tubules of nanometer dimensions[l] and the subsequent report on the observation of conditions for the synthesis of large quantities of nanotubes[2,3]. Since these early reports, much work has been done, and the results show basically that carbon nanotubes behave like rolled-up cylinders of graphene sheets of bonded carbon atoms, except that the tubule diameters in some cases are small enough to exhibit the effects of one-dimensional (ID) periodicity. In this article, we review simple aspects of the symmetry of carbon nanotubules (both monolayer and multilayer) and comment on the significance of symmetry for the unique properties predicted for carbon nanotubes because of their ID periodicity. 

Ivanov, V., J.B. Nagy, P. Lambin, A. Lucas, X.B. Zhang, The study of carbon nanotubules produced by catalytic method. Chem. Phys. Lett. 223, 329,1994. 

Che GL, Lakshmi BB, Fisher ER, Martin CR (1998) Carbon nanotubule membranes for electrochemical energy storage and production. Nature 393 346-349. 

It is important to note that in addition to microporous solids, other chemical systems have been used to template the growth of nanomaterials. For example, emulsions have been used to pattern both the pores in titania [14] and the packing of latex particles [46]. Reversed micelles have also been used as patterning agents. Examples include the syntheses of super-paramagnetic ferrite nanoparticles [15] and BaC03 nanowires [47]. Finally, carbon nanotubules have also been used as templates [16,48,49]. A variety of nanomaterials including metal oxides [16,48,49] and GaN have been synthesized inside such tubules [50]. 

Lam CW, James JT, McCluskey R, Hunter RL (2004) Pulmonary toxicity of single-waU carbon nanotubules in mice 7 and 90 days after intratracheal instillation. Toxicol Sci 77 126-134... 

A more defective form of sp carbon fibers, carbon nanotubules (CNTbs), grown by pyrolytic deposition of carbon into anodized aluminum oxide (AAO) nanochannels, are also used as nanoelectrode arrays for electrochemical sensors. Small graphitic crystallites are deposited on the inner surface of the nanochannels. Since the crystallites do not extend very long (less than micrometers) and are structurally discontinued, the resistance is orders of magnitude higher than CNFs... 

BEKKEDAHL, T.A., HEBEN, M.J., Advanced Materials for Hydrogen Storage Carbon Nanotubules, (DOE/NREL Hydrogen Program Review, Livermore, 1994). BOLTENDAHL, U., HARTH, R., Warmetransport auf kaltem Wege, Bild der Wissenschaft 17 (1980) April 44-55. 

Mao, et al. Molecular dynamics simulations of the filling and decorating of carbon nanotubules. Nanotechnology. 1999,10, 273-277. 

Fig. 1.9 Molecular models using Tersoff potentials allow for study of a wide range of static, dynamic and thermodynamics properties of carbon forms here carbon nanotubules are shown in several phases of buckling [389]. Image courtesy Prof. Junichiro Shiomi and Dn Takuma Shiga, Department of Mechanical Engineering, University of Tokyo...

Cooper SM, Craden B, Meyyappan M, Raju R, Roy S (2004) Gas Transport Characteristics Through a Carbon Nanotubule. Nano Lett 4(2) 377-381... 

Carbon nanotubule short hollow two exper. vapor phase 2.2.7... 

Carbon nanotubules Water-soluble multiwalled carbon nanotubules Graphene or graphene oxide negative-ion mode Traditional Chinese medidnes... 

Figure 4 TEM images of carbon nanotubule (a) and PtRu/CNT (b), and cyclic voltammo-grams of methanol oxidation on A after deposition of Pt/Ru nanopartide, and B before deposition of Pt/Ru nanoparticles, 2 M methanol -l-1 M H2SO4 (c) [200].

Che et al. first explored porous alumina template to prepare carbon nanotubule with a diameter of 200 nm and wall thickness of 20 nm (Figure 4.8). After impregnating PtRu precursors into the CNT, HF was employed to remove AI2O3 frames. Small and uniform PtRu nanoparticles (1.59 0.3 nm) were obtained after 3 h H2 reduction at 580 °C. The carbon nanotubule-supported PtRu nanoparticles have demonstrated very large and characteristic methanol oxidation waves in acid electrolyte [200]. Using a similar method, Rajesh et al. studied the methanol oxidation activity on a series of MWNTs (200nm in diameter) and found their activity sequence is PtRu/MWNTs> Pt-W03/MWNTs> PtRu/XC-72 [203]. 

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