Multiwall nanotubes

Fig. 2. A graphic of a nanotube showing a pulled-out atomic wire and several stabilizing spot-welds. Only two layers have been shown for clarity, although typical multiwalled nanotubes have I0-I5 layers. The spot-weld adatoms shown between layers stabilize the open tip conformation against closure. The atomic wire shown was previously part of the hexagonal lattice of the inner layer. It is prevented from pulling out further by the spot-weld at its base.

The multiwalled nanotubes as well as the herringbone type carbon nanofibers were synthesized in-house in a quartz glass fluidized bed reactor via chemical vapor deposition (CVD). The method is described in detail elsewhere.19 The platelet nanofibers, in contrast, were purchased from the company FutureCarbon GmbH (Bayreuth, Germany). 

FIGURE 2.1 Cobalt functionalized (a) platelet type carbon nanofibers, (b) herringbone type carbon nanofibers, and (c) carbon multiwalled nanotubes. 

To some extent the cobalt particles in Figure 2.1(c) seem to be distributed within the tubular structure of the multiwalled nanotubes. TEM analysis could not fully clarify if this is an artifact or if the particles are truly situated inside the hollow space of the tubes. However, Tavasoli et al.14 observed Co particles captured inside the tubes after incipient wetness impregnation. Thus, it can be assumed that this is the case here as well. 

Figure 5. Tetrabenzodehydroannulene 13 was discovered bon onions and multiwalled nanotubes, partially containing to undergo explosive decomposition under formation of crystalline metal deposits in their interior were obtained by...

Multivariate curve resolution, 6 54—56 Multivariate linear regression, 6 32—35 Multivariate optical elements (MOE), 6 68 Multiwalled carbon nanotubes (MWCNTs), 77 48, 49 22 720 26 737. See also Carbon nanotubes (CNTs) Multiwall nanotubes (MWNTs) synthesis of, 26 806 Multiwall fullerenes, 12 231 Multiwall nanotubes (MWNTs), 12 232 Multiwall paper bags, 78 11 Multiway analysis, 6 57-63 Multiyear profitability analysis, 9 535-537 Multiyear venture analysis, 0 537-544 sample, 9 542-S44 Mummification, 5 749 Mumps vaccine, 25 490 491 Mumps virus, 3 137 Municipal biosolids, as biomass, 3 684 Municipal distribution, potential for saline water use in, 26 55-56 Municipal effluents, disposal of, 26 54 Municipal landfill leachate, chemicals found in, 25 876t... 

Schematic of the hydrogen fuel cell architecture using an ultra-low Pt loading thin-film Pt/ MWNT catalyst layer (MWNT = multiwalled nanotube). (Reproduced with permission from Tang, J. M. et al. Journal of Physical Chemistry C 2007 111 17901-17904. Copyright 2007 American Chemical Society.)...

Multiwalled nanotubes have now been synthesized from inorganic compounds tubes up to 1 pm in length have been formed from WS2 and M0S2. 

Rings can form from nanotubes, when the two ends join each other. Concentric multiwall nanotubes can form as well as single-thickness nanotubes. 

Figure 5. EELS analysis of a multiwall nanotube. Left TEM image middle element analysis as a function of probe position right schematic view of the different layers constituting the tube, (from Suenaga K. et al, Science 278 (1997) 653 with permission from Science)...

Coating by a thin layer of PPy has been realized on multiwalled nanotubes (MWNT) [29,91,93], well-aligned MWNT [85] and single-wall nanotubes (SWNT) [88], When MWNT are oxidized, their surface is covered with oxygenated functionalities, which can be used as anionic dopant of a PPy film electrodeposited on the MWNT [94], These films are notably less brittle and more adhesive to the electrode than those formed using an aqueous electrolyte as source of counterion. 

Abstract. It has been revealed that carbonic nanomaterials (fullerene, single- and multiwall nanotubes, nanofibers) display high activity at low temperatures (77K) in reactions of chain halogenation (F2, Cl2) with kinetic chain length up to 104 -105. The ESR spectra of active free- radical intermediates were recorded. The presence of vibration bands of C-Cl bonds in products has been indicated by IR method. 

Figure 5. Carbon multiwall nanotubes produced by uncatalytic evaporation of graphite in distilled water.

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