Nanocable

Figure 12.8 (a) FESEM image of prepared nanoc stals. (b) Size distribution of the nanoc stals evaluated from the FESEM image (a). This distribution was built up by scaling the long-axis of 100 individual nanocrystals. 

X. Zhang, J. Zhang, R. Wang, and Z. Liu, Cationic surfactant directed polyaniline/CNT nanocables synthesis, characterization, and enhanced electrical properties. Carbon 42, 1455—1461 (2004). 

Moreover, some samples of nanoC can contain the organic solvents or product of their degradation, capable of revealing pronounced toxic action (Oberdorster 2004 Fortner et al. 2005 Henry et al. 2007). 

The production of Ag Carbon nanocables was reported by Yu et al. [20]. In this case the authors used the hydrothermal carbonization of starch in the presence of Ag N03 leading to the one-step formation of carbon/Ag hybrid nanocables. Such silver-carbon nanocables can have a length as long as 10 mm and overall diameters of 1 micron with a 200-250 nm silver lining. When made at higher concentrations, they tend to fuse with each other (Fig. 7.5(a) and (b)). This method was extended to a polyvinyl alcohol(PVA)-assisted synthesis of flexible noble metal (Ag, Cu) carbon composite microcables [21]. 

Fig. 7.5 (a) Typical SEM image of the nanoscaie with encapsulated, silver nanowires. The insert shows an incompletely drilled tube with a pentagonal cross-section, (b) TEM image of typical silver-carbon nanocables formed after treating at 160 °C for 12 h 5 g starch, 5 mmoi AgN03, pH 4. 

L. Zaluski, A. Zaluska, P. Tessier, J.O. Strom-Olsen, R. Schulz, Hydrogen absorption in nanoc-rystaUine Mg Ni formed by mechanical alloying, J. Alloys Compd. 217 (1995) 245-249. 

Figure 9.7 Typical TEM images (a) and (b) of the as-prepared gold/platinum hybrid NPs supported coaxial nanocables at different magnifications.132 (Reprinted with permission from S. Guo et al., J. Phys. Chem. C. 2008,112, 2389-2393. Copyright 2008 American Chemical Society.)...

Fig. 29 TEM image of metal core/carbon sheath nanocables with a long, iron-containing core and a spindle-like tip. The TEM image is reprinted with permission from [216]. Copyright 2005, Wiley-VCH...

Self-Assembly of PPEs on Surfaces From Jammed Cel Phases to Nanocables and Nanowires... 

Fig. 16. (a) Nanocable arrangement of didodecyl-PPE 12c on a silicon wafer [60]. The observed superstructure exceeds the size of single lamellae, (b) Nanowires and (c) nanoribbons of PPEs 12a as observed by Samori, Mullen, and Rabe [59], Single polymer chains are visible in... 

While the formation of the nanoribbons can be explained in terms of a crystallization process that leads to these structures on solid surfaces, the formation of the nanocables and nanowires is not so straightforward. The origin of the cable-like structures thus became a topic of interest. They could either arise by a crystallization process when a homogeneous solution of 12 is dried on a surface, or these superstructures could be preformed in solution and act as seeds for the subsequent growth of cables. 

This gel phase has not been described, and consists of aggregates that are approximately 7 nm in diameter and several pm long (Figure 17). Due to their size, the flat aggregates cannot flow freely, restrict the movement of the solvent, and form a gel. Upon casting onto surfaces, these nanocylinders seed the growth of the nanocables observed in thin solid films. 

Zhang, Y - Suenaga, K. Coiiiex. C. lijima. S. Coaxial nanocable Silicon carbide and silicon oxide sheathed with boron nitride and carbon. Science 1998 281. 973,... 

Nanocables of BN nanotubes filled with Mo clusters are reported by Golberg el al, a The Mo cluster-filled BN nanotubes are prepared by the treatment of CVD grown CNTs with BjO, CuO and MoO, in a N2 atmosphere. It has been proposed that the filling of CNTs with Mo03 precedes the formation of BN tubes on the CNT template. The filling of MoO, is then further reduced to metallic Mo by the carbon of the CNTs. Continuous filling of Mo could not be obtained by this method. 

Fig. 16.17 SEM image of Ti02/CdS nanocables prepared by templated liquid-phase deposition [Reprinted from Hsu et al. (2005), Copyright (2005), with permission from Elsevier]...

Fig. 4.2. Nanoc stalline film of Au formed at the toluene-water interface (middle).

Fig. 4.14. A bimodal hexagonal array of Au nanoc stals. The radius ratio of the nanoc stals is 0.58 (reproduced with permission from [113]).

Fig. S.1. Transmission micrographs of the magnetotactic bacteria Magnetospirillium magnetotacticum taken in two different directions. The precise control of both the magnetite nanoc stal shape and size, as well...

Fig. 7.6. Absorption and photoluminescence (PL) spectra of as-prepared products, GaP nanoc stals (A) and InP nanocrystals (B).

Fig. 7.12. XRD patterns (a) and TEM images (b) and (c) of the InSb nanoc stals prepared by NaBH4 reduction of InCIs in the presence of Sb at 100 to 200 °C in ethylenediamine.

Fig. 7.37. Solution route fabricated CdSe-wire/poly(vinyl acetate)-sheath nanocable by y-irradiation. (a) TEM image at lower magnification (b) TEM image at higher magnification and inserted ED pattern of the same area (c) HRTEM image of the nanocable.

The nanowires themselves can be used as templates to generate the nanowires of other materials. The template may be coated onto the nanowire (physically) forming coaxial nanocables [316a], or it may react with the nanowires forming a new material [317a,b]. In the physical (solution or sol-gel coating) approach, the surfaces of the nanowires could be directly coated with conformal sheaths made of a different material to form coaxial nanocables. Subsequent dissolution of the original nanowires could lead to nanotubes of the coated material. The sol-gel... 

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