Carbon nanotubes separation

H. Dodziuk, A. Ejchart, W. Anczewski, H. Ueda, E. Krinichnaya, G. Dolgonos, and W. Kutner, Water solubilization, determination of the number of different types of single-wall carbon nanotubes and their partial separation with respect to diameters by complexation with r/-cyclodextrin, Chem. Commun. (2003) 986-987. 

Jess, A., Kern, C., Schrogel, K., Jung, A., and Schiitz, W. 2006. Manufacturing of carbon nanotubes and -fibers through gas phase separation. Chemie Ingenieur Technik 78 94-100. 

Carbon nanotube films possess enormous potential for a variety of applications. The major limitations at present are associated with heterogeneity of as-synthesized nanotubes and with difficulties in separating CNTs with semiconducting and metallic characteristics. If this problem will be solved in... 

Krupke, R. Hennrich, F. v. Lohneysen, H. Kappes, M. M. 2003. Separation of metallic from semiconducting single-walled carbon nanotubes. Science 301 344-347. 

The main difference between titania nanotube and the ID nanostructures discussed before is the presence of an hollow structure, but which has significant consequences for their use as catalytic materials (i) in the hollow fiber nanoconfinement effects are possible, which can be relevant for enhancing the catalytic performance (ii) due to the curvature, similarly to multi-wall carbon nanotubes, the inner surface in the nanotube is different from that present on the external surface this effect could be also used to develop new catalysts and (iii) different active components can be localized on the external and internal walls to realize spatially separated (on a nanoscale level) multifunctional catalysts. 

Zheng M, Jagota A, Semke ED, Diner BA, Mclean RS, Lustig SR, Richardson RE, Tassi NG (2003a) DNA-assisted dispersion and separation of carbon nanotubes. Nature Mater. 2 338-342. 

Foster J, Singamaneni S, Kattumenu R, Bliznyuk V (2005). Dispersion and phase separation of carbon nanotubes in ultrathin polymer films. J. Colloid and Interface Science 287 167-172. 

Maeda Y, Kanda M, Hashimoto M, Hasegawa T, Kimura S, Lian YF, Wakahara T, Akasaka T, Kazaoui S, Minami N, Okazaki T, Hayamizu Y, Hata K, Lu J, Nagase S (2006) Dispersion and separation of small-diameter single-walled carbon nanotubes. J Am Chem Soc 128 12239-12242. 

Functionalization of carbon nanotubes with metals can be achieved by different techniques exploiting either the covalent or the noncovalent approach. This topic, which is important for many applications, will be briefly discussed in a separate section after the description of the two methods. 

Yu, H. Quan, X. Chen, S. Zhao, H., Ti02-multiwalled carbon nanotube heterojunction arrays and their charge separation capability. J. Phys. Chem. C 2007, 111, 12987-12991. 

Stranks, S. D. Weisspfennig, C. Parkinson, P. Johnston, M. B. Herz, L. M. Nicholas, R. J., Ultrafast charge separation at a polymer-single-walled carbon nanotube molecular junction. Nano Lett. 2011,11, 66. 

Apart from the promising electrochemical properties that will be exhaustively discussed through this chapter, carbon nanotubes have become a hot research topic due to their outstanding electronic, mechanical, thermal, optical and chemical properties and their biocompatibility. Near- and long-term innovative applications can be foreseen including nanoelectronic and nanoelectromechanical devices, held emitters, probes, sensors and actuators as well as novel materials for mechanical reinforcement, fuel cells, batteries, energy storage, (bio)chemical separation, purification and catalysis [20]. 

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