Nanofiber, preparation

SEM of graphitic nanofiber prepared by decomposition of C2H4 H2 = 1 4 gas flow over NiCu alloy powder. (Reproduced from Xu, W.-C., Takahashi, K., Matsuo, Y., Hattori, Y., Kumagai, M., Ishiyama, S., Kanekoc, K., and Iijima, S., Int. ]. Hydrogen Energ. 32(12), 2504-2512, 2007. With permission.)... 

Fig. 10.1.8 SEM photographs of (a) the carbon nanotube and (b) the nanofibers prepared by ethylene CVD. (From Ref. 25.)...

Rollings DA et al (2007) Formation and aqueous surface wettability of polysiloxane nanofibers prepared via surface initiated, vapor-phase polymerization of organotrichlor-osilanes. Langmuir 23(10) 5275-5278... 

Kuo CC, Wang CT, Chen WC (2008) Highly-aligned electrospun luminescent nanofibers prepared from polyfluorene/PMMA blends fabrication, morphology, photophysical properties and sensory applications. Macromol Mater Eng 293( 12) 999—1008... 

The hydrogenation of nitrobenzene was carried out on palladium supported on the carbon nanofibers prepared according to the preceding method without further purification and compared to a commercial palladium catalyst supported on a high surface area activated charcoal (Aldrich, 970 m /g). 

Figure 8.5 PANI nanofibers prepared by Kim et al. (Reproduced with permission from [51] [55b]. Copyright (2005) IOP Science).

Y. Suzuki, S. Pavasupree, S. Yoshikawa, R. Kawahata, Natural rutile-derived titanate nanofibers prepared by direct hydrothermal processing . Journal of Materials Research., 20,1063-1070, (2005). 

Inagaki, M. Y. Yang, and F. Kang, Carbon nanofibers prepared via electrospinning. 

Cheng, K. K. T.C. Hsu, and L.H. Kao, A microscopic view of chemically activated amorphous carbon nanofibers prepared from core/sheath melt-spiiming of phenol formaldehyde-based polymer blends. J. Mater. Sci. 2011,46(11), 3914-3922. 

Y. Wang, X. Jing, and J. Kong, Polyaniline nanofibers prepared with hydrogen peroxide as oxidant, Synth. Met., 157, 269-275 (2007). 

C-C. Kuo, C-H. Lin, and W-C. Chen, Morphology and photophysical properties of light-emitting electrospun nanofibers prepared from poly(fluorene) derivative/PMMA blends. Macromolecules, 40, 6959-6966 (2007). 

H-C. Chen, C-T. Wang, C-L Liu, Y-C. Liu, and W-C Chen, Full color light-emitting electrospun nanofibers prepared from PFO/MEH-PPV/PMMA ternary blends, J. Polymer Sci. B Polymer Phys., 47, 463 70 (2009). 

Y-W. Ju, J-H. Park, H-R. Jung, and W-J. Lee, Electrochemical properties of polypyrrole/ sulfonted SEBS composite nanofibers prepared by electrospinning, Electrochim. Acta, 52, 4841 847 (2007). 

G.M. do Nascimento, P.Y.G. Kobata, and M.L.A. Temperini, Structural and vibrational characterization of polyaniUne nanofibers prepared from interfacial polymerization, J. Phys. Chem. B, 112, 11551-11557 (2008). 

Models have been constructed with cross-sections that have diameters of 7-8 nm. They are comparable in thickness with some of the nanofibers prepared by the electrospinning technique, which can be as thin as 3 nm (D. H. Reneker, personal communication). If the fiber has a thickness greater than about 4 nm, it recovers bulk density in its interior. 

Fukuzumi, H., Saito, T., Wata, T., Kumamoto, Y., Isogai, A. Transparent and high gas barrier films of cellulose nanofibers prepared by TEMPO-mediated oxidation. Biomacromolecules. 10, 162-165 (2009)... 

Vargas, N.H., 2010. Aligned Cellulose Nanofibers Prepared by Electrospinning. University Press, Lulea. 

Ifiiku S, Saimoto H (2012) Chitin nanofibers preparations, modifications, and applications. Nanoscale 4 3308-3318... 

Saito T, Kimura S, Nishiyama Y, Isogai A (2007) Cellulose nanofibers prepared by TEMPO-mediated oxidation of native cellulose. Bimnataomolecules 8 2485-2491... 

Lee, L.H., Ed. (1977). Characterization of Metal and Polymer Surfaces Polymer Surfaces Academic Press, ISBN-10 0124421016, New York, USA Li, H., Liu, T., Li, Z. Deng, L. (2008). Low-cost supports used to immobilize fungi and reliable technique for removal hexavalent chromium in wastewater. Bioresource Technology, Vol.99, (May 2008), No.7, pp.2234-2241, ISSN 0%0-8524 Liu, Y., Pan, C., Wang, J. (2004) Raman spectra of carbon nanotubes and nanofibers prepared by ethanol flames. Journal of Materials Science, Vol.39, No.3, (February 2004) pp. 1091-1094, ISSN 0022-2461... 

Fig. 7 PS-1)-PMMA nanofibers prepared by capillary wetting into AAO hard templates, a Tips with menisci b section through a PS-fi-PMMA nanofiber array, evidencing the solid rod-like nature of the nanofibers. The SEM images are a courtesy Dr. Olaf Kriha...

Fig.18 PMMA/discotic composite nanofibers prepared inside AAO hard templates, a Nanotube (diameter about 400 nm) with a wall consisting of an outer PMMA layer and an inner (stained) discotic layer b nanorod (diameter 60 nm) with a disordered segmented morphology. Reproduced from [65]. (2005) Wiley-VCH...

Figure 2.11 SEM image of carbon nanospheres (left-above] and after (left-below] calcination of nanofibers prepared with carbon nanospheres, and XRD patterns of TiOj nanofibers (right] (a] and porous TiOj nanofibers (b]. Reprinted from Ref. 62, Copyright 2012 Shanhu Liu et al.

Figure 5.20 Average diameter of electrospun PEDOT-PSS/PVP nanofibers prepared from DMF as a function of applied potential (flow rate 0.2 mL/h tip-collector distance 15 cm). ...

Figure 5.21 SEM images of electrospun nanofibers prepared from DMF solution, (a) PEDOT-PSS/PVP (applied voltage 18 kV flow rate 0.2 mL/h tip-to-collector distance 15 cm] and (b] PVP (applied voltage 11 kV flow rate 0.1 mL/h tip-to-collector distance 15 cm). Reprinted with permission from Ref 160, Copyright 2010 Elsevier Ltd.

Polyamide 6 (PA-6)/polypyrrole-conductive nanofibers, prepared by the pol5merization of pyrrole on the fiber surface, were studied. A solution of PA-6 added with ferric chloride in formic acid was elec-trospun and the fibers were exposed to pyrrole vapours. Potyp3UTole was formed on the fiber surface. Polypyrrole-polyethyleneoxide... 

Figure 8.8 Schematic illustration of the composite nanofiber preparation...

In the case of commercial MWCNTs as ftRu support, Jeng et al. [31] used this kind of support previously activated by chemical treatment. Well dispersed PtRu 1 1 nanoparticles of 3.5-4 nm were obtained by a polyol synthesis method. The fuel cell test showed a performance 50 % higher than that of a commercial PtRu on Vulcan support (E-TEK). Similar results were found by Prabhuram et al. [32] for PtRu on oxidized MWCNT, where well dispersed nanoparticles of 4 nm were obtained by the NaBH4 method. The DMFC performance test of PtRu supported on MWCNTs showed a power density ca. 35 % higher than that using the Vulcan carbon support. Outstanding results were obtained by Tsuji et al. [33] with PtRu nanoparticles supported on carbon nanofibers prepared by polyol method and tested in a DMFC. They obtained a performance 200 % higher than standard PtRu on Vulcan carbon from Johnson Matthey. 

Besides CNTs, another ID carbon nanostructure is carbon nanoflbers. For example, Shen et al. [156] prepared a series of hierarchical porous carbon libers with a BET surface area of 2,231 m g and a pore volume of 1.16 cm g. In this synthesis method, the polyacrylonitrile (PAN) nanofibers (prepared by dry-wet spinning) were selected as precnrsors, and pre-oxidation and chemical activation were involved to get the developed porosities. This type of material contained a large amount of nitrogen-containing groups (N content >8.1 wt%) and consequently basic sites, resulting in a faster adsorption rate and a higher adsorption capacity for CO2 than the commercial zeolite 13X that is conventionally used to capture CO2, in the presence of H2O (Fig. 2.27). 

S., Hasebe, T., and Hotta, A. (2014) Preparation and characterization of 2-methacryloyloxyethyl phosphorylcholine polymer nanofibers prepared via electrospinning for biomedical materials. J. Appl. Polym. Sci, 131, 40606... 

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