Silanes carbon nanotube

The next step Ifom Silicon-based sheet polymers to tubular structures has been performed so far only on the computer. In Chapter 17, Th. Frauenheim et al. describe the structure and the electronic properties of silicide, silane and siloxane nanotubes. The structures can be understood in terms of conventional graphitic carbon nanotubes by replacing the flat hexagons by puckered rings. The electronic properties depend on the tube diameter. Potential applications are discussed. 

C. Velasco-Santos, A.L. Martinez-Hernandez, W. Brostow, and V.M. Castano, Influence of silanization treatment on thermomechanical properties of mul-tiwalled carbon nanotubes Poly(methybnethacrylate) nanocomposites. Journal of Nanomaterials, 2011, 928659, 2011. 

Zhou, Z., Wang, S., Lu, L., Zhang, Y, and Zhang, Y. 2008. Functionalization of multi-wall carbon nanotubes with silane and its reinforcement on polypropylene composites. Composites Science and Technology 68 1727-1733. 

A number of reports have described theoretical calculations for superhydrophobic surfaces. Marmur [10] and Quere and co-workers [11,12] show the theoretical background for surface roughness. There are also many reports regarding creation of superhydrophobic surfaces using hthography [13], fractal structure of wax [14], chemical vapor deposition (CVD) of poly(tetrafluoroethylene) (PITH) [15] carbon nanotubes and web-like structures [16-18] and by coating hydrophobic silanes onto aluminum acetylacetonate [19] and so on. These micro-structured surfaces show a decrease in apparent surface free energies. 

Functionalized multi-walled carbon nanotubes (MWNTs) were prepared by acid treatment followed by reaction with 3-aminopropyltriethoxysilane. Reaction of silane with oxidized nanotubes was confirmed by Fourier transform infrared (FTIR) spectroscopy and energy dispersive X-ray (EDX) analysis to confirm silicon on the surface of the MWNTs. Raman spectroscopy of the acid-treated MWNTs confirmed formation of surface defects due to carboxyl... 

In addition to growth of SiNWs, one-dimensional composite structures prepared by vacuum deposition of silicon clusters on CNTs also have been investigated. Hybrid silicon/carbon nanotube one-dimensional nanostructures were synthesized using a two-step CVD process (see Fig. 15.8) [18]. The spaces between the CNTs, formed through controlled nucleation in the first deposition step, allow for subsequent penetration of silane gas and a homogenous deposition of silicon clusters on the surfaces of the CNTs during the second CVD deposition step. The hybrid silicon/CNTs exhibit a high reversible capacity of 2,000 mAh/g with a 0.15% capacity loss per cycle over 25 cycles. When compared with commercially available silicon particles, in situ prepared silicon by CVD always has a smaller irreversible capacity loss in the first cycle. This may be related to the reduced amount of SiOx on the surface of the silicon particles which usually traps lithium in... 

Qin et al. [114] prepared functionalized single-walled carbon nanotubes (SWNTs) through treatment of polystyrene via the grafting-to method. The results showed that the PS was covalently attached to the side walls of SWNTs. The poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) was functionalized with glycidyl methacrylate (GMA) via atom transfer-radical polymerization (ATRP) and the BaTiOs nanoparticles were modified by amino-terminated silane molecules. Then, the nanocomposites with high dielectric coti-stant and high thermal conductivity were prepared by a grafting to method [115]. 

Figure 14.21. Transmission electron micrographs of Pt nanoparticles deposited on MWCNTs. (a) In the absence of the silane precursor (b) in the presence of the silane precursor (c) higher magnification TEM of (b) [155]. (Reprinted from Chemical Physics Letters, 379(1-2), Sun X., Li R., Villers D., Dodelet J P, DesUets S, Composite electrodes made of Pt nanoparticles deposited on carbon nanotubes grown on fuel cell backings, 99-104, 2003, with permission from Elsevier.)...

Ma PC, Kim J-K, Thang BZ. FunctionaUzation of carbon nanotubes using a silane coupling agent. Carbon 2006 44 3232-8. 

Ko H-H, Cheng Y-Y, Dai C-A (2014) Silane modified multiwall carbon nanotubes/polyimide composites prepared using in-situ polymerization. Nanosci Nanotechnol Lett 6(3) 190-196 Koga H, Saito T, Kitaoka T, Nogi M, Suganutna K, Isogai A (2013) Transparent, conductive, and printable composites consisting of TEMPO-oxidized nanocellulose and carbon nanotube. Biomacromolecules 14(4) 1160-1165... 

Additives used in final products Fillers antimony trioxide, aramid, barium sulfate, boron nitride, calcinated kaolin, carbon black, carbon fiber, glass fiber, glass spheres, mica, montmorillonite, talc, titanium dioxide, zinc borate Antistatics antimony-doped tin oxide, carbon nanotubes, polyaniline, polyisonaphthalene Antiblocking calcium carbonate, diatomaceous earth, silicone fluid, spherical silicone resin, synthetic silica Release calcium stearate, fluorine compounds, glycerol bistearate, pentaerythritol ester, silane modified silica, zinc stearate Slip spherical silica, silicone oil ... 

Ma, P.C., Kim, J.-K., Tang, B.Z., 2007. Effects of silane functionalization on the properties of carbon nanotube/epoxy nanocomposites. Composites Science and Technology 67, 2965-2972. 

K. Yang and M. Gu, "Enhanced thermal conductivity of epoxy nanocomposites filled with hybrid filler system of triethylenetetramine-functionalized multi-walled carbon nanotube/silane-modified nano-sized silicon carbide," Composites Part A, vol. 41, pp. 215-221,2010. 

Sol-gel materials are also known as an excellent matrix for embedding other species due to their tunable physical properties (e.g., flexibility and transparency), high chemical stability, and mild operating conditions. Especially, electrochemical deposition of silane-based sol-gel Aims is usually carried out under mild acidic aqueous solutions at pH 3-6. This allows the co-electrodeposition of silane with nanoparticles [47-50], carbon nanotubes [51-53], metals [54-57], polymers [50,58], enzymes [52,53,59-65], bacteria [66,67], and more. Thus, most of the recent research worlcs also focus on the electrochemical deposition of sol-gel-based composite Aims, with the concern of improving the films performance in corrosion protection, electroanalysis, microextraction, and so on and further broadening the films applications. 

The performance of the films can be further improved by co-electrodeposition with other species such as metals, nanoparticles, and carbon nanotubes. Moreover, electrodeposited sol-gel films may also serve as a platform for embedding fiuictional materials. Specifically, the sol-gel system is ideal for immobilizing bioactive species, such as enzymes and bacteria thus, electrodeposition approach allows simple one-step fobrication of biosensors. Electrodeposition also yields selective deposition of silane/CNT antireflective coatings on conductive patterns. Molecularly imprinted films are prepared by co-electrodeposition of the target molecule with sol-gel followed by its removal. 

M.A. Aziz, S. Park, S. Jon, H. Yang, Amperometric immunosensing using an indium tin oxide electrode modified with multi-walled carbon nanotube and poly(ethylene glycol)-silane copolymer, Chem. Commun. (2007) 2610-2612. 

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