Carbon nanotube forest

Yu X, Chattopadhyay D, Galeska I, Papadimitrakopoulos E, Rusling JE. 2003. Peroxidase activity of enzymes bound to the ends of single-wall carbon nanotube forest electrodes. Electrochem Commun 5 408-411. 

M. O Connor, S.N. Kim, A.J. Killard, R.J. Forster, M.R. Smyth, F. Papadimitrakopoulos, and J.F. Rusling, Mediated amperometric immunosensing using single walled carbon nanotube forests. 

The field emission properties of carbon nanotube forests and single nanotubes are described. Controlled emission is possible for aligned CNT arrays where the spacing is twice the CNT height, as grown by plasma enhanced chemical vapor deposition. This leads to the maximum field enhancement factor. For random forests, the field enhancement obeys an exponential distribution, leading to a lower emission site density and imperfect current sharing. Ballast resistors can help alleviate this problem. Random nanocarbons perform less well than CNTs. Some applications are covered. Elec-... 

W. I. Milne, G. H. McKinley, and K. K. Gleason, Superhydrophobic Carbon Nanotube Forests, Nano Lett. 2003, 3, 1701. 

J.F. Rusling, Mediated amperometric immunosensing using single walled carbon nanotube forests. 

Figure 13.13 SEM images showing the dry spinning of nanotube yams from a multiwalled carbon nanotube forest The torque-stabiUzation applied during spinning results in yarns of superior strength. (Images from References 123 and 124.)...

In Fig. 7.6 are presented the typical SEM images with different magnifications of the carbon nanotubes forest generated via the pyrolysis of ferrocene in a toluene flow reahzed in the laboratory. 

The synthesis was carried out at 850 °C with a flow rate of 100 ml min" of toluene and 5 vol.% ferrocene. The ferrocene was located at the entrance of the reactor in a low temperature zone, ca. 500 °C. The macroscopic pieces of carbon nanotubes were recovered from the quartz substrate located in the hottest zone of the reactor. According to the SEM observation the thickness of the aligned carbon nanotubes forest was relatively high, approaching almost 250 pm, while the diameter was relatively homogeneous at around 50 nm. The height of the carbon nanotubes... 

Fig. 7.6 (A) Sheet of parallel carbon nanotubes forest with a height of 250 pm. The height of the carbon nanotubes forest can be easily controlled from ca. 100pm up to 500pm. (B, C) High-resolutlon SEM images showing the details morphology of the patterned carbon nanotubes with a homogeneous diameter centered at around 50 nm. The aspect ratio value of these patterned carbon nanotubes was around 5000.

In summary, the catalytic route provides an interesting way to prepare carbon nanotubes with high yield and selectivity at relatively low synthesis temperature. The easy scale-up of the catalytic method allows one to ensure the mass production of these ID materials with reasonable cost for large scale applications. The development of different methods to produce carbon nanotubes in a controlled macroscopic shape and size, i.e. constraint synthesis, patterned and aligned carbon nanotubes forest by pyrolysis of organic compounds, avoids the formation of fines... 

Futaba, D.N., Hata, K., Namai, T., Yamada, T., Mizuno, K., Hayamizu, Y., et aL, 2006. 84% Catalyst activity of water-assisted growth of single walled carbon nanotube forest characterization by a statistical and macroscopic approach. J. Phys. Chem. B 110, 8035—8038. 

Yang, L., B. H. Fishbine, A. Migliori, and L. R. Pratt 2009. Molecular simulation of electric double-layer capacitors based on carbon nanotube forests. Jourrud of the American Chemical Society 131 12373-12376. 

Lau KKS, Bico J, Teo KBK, Chhowalla M, Amaratunga GAJ, Milne Wl, McKinley GH, Gleason KK (2003) Superhydrophobic carbon nanotube forests. Nano Lett 3 1701... 

Qi HJ, Teo KBK, Lau KKS, Boyce MC, Milne WI, Robertson J, et al. Determination of mechanical properties of carbon nanotubes and vertically aligned carbon nanotube forests using nanoindentation. J Mech Phys Solids 2003 51 2213-37. 

Wirth CT, Zhang C, Zhong G, Hofmann S, Robertson J. Diffusion—and reaction— limited growth of carbon nanotube forests. ACS Nano 2009 3 3560-6. 

Esconjamegui S, Bayer BC, Fouquet M, Wirth CT, Yan F, Xie R, et al. Use of plasma treatment to grow carbon nanotube forests on TiN substrate. J Appl Phys 2011 109 1143121-11431210. 

Mattevi C, Wirth CT, Hofmann S, Blume R, Cantoro M, Ducati C, et al. In-situ X-ray photoelectron spectroscopy study of catalyst—support interactions and growth of carbon nanotube forests. J Phys Chem C 2008 112 12207-13. 

Malhotra, R., Papadimitrakopoulos, F., Rusling. J. F. Sequential layer analysis of protein immunosensors based on single wall carbon nanotube forests. Langmuir 26, 15050-15056... 

Munge, B.S., Krause, C.E., MaUiotra, R., Patel, V., Gutkind, J.S., Rusling, J.F. Electrochemical immunosensors for Interleukin-6. Comparison of carbon nanotube forest and gold nanoparticle platforms. Electrochem. Comm. 11, 1009-1012 (2009)... 

Jensen, D.S., Kanyal, S.S., Gupta, V., Vail, M.A., Dadson, A.E., Engelhard, M., Vanfleet, R., Davis, R.C., and Linford. M.R. 2012. Stable, microfabricated thin layer chromatography plates without volume distortion on patterned, carbon and AljOj-primed carbon nanotube forests, J. Chromatogr. A, 1257 195-203. 

Fig. 1.6 Number of papers published concerning the production of carbon nano-tubes and carbon nanotubes forests from 2003 to mid-2013 (www.sdencedirect.com, accessed on 27th of July 2013)...

One of the latest advances in this field was the use of water vapor during the synthesis. The addition of small fractions of water helps to keep the catalyst active for much longer to selectively oxidize the amorphous carbon. Water assisted CCVD greatly enhances the quality of the produced carbon nanotubes forests, not only increasing their height (from micrometers to millimeters), but also reducing the amount of impurities. 

Yasuda, S., Futaba, D.N., Yamada, T., et al. Improved and large area single-walled carbon nanotube forest growth by controlling the gas flow direction. ACS Nano 3(12), 4164-4170 (2009)... 

The following chapters present the general aspects of different synthesis of nanostructured materials, such as Combustion Synthesis (Chap. 2), Spray Pyrolysis (Chap. 3), Electro spinning (Chap. 4), Catalytical Chemical Vapor Deposition applied in the Synthesis of Carbon Nanotubes and Carbon Nanotubes Forests (Chap. 5), Hydrothermal Synthesis (Chap. 6) and High-Energy Milling (Chap. 7). 

Alam MK, Yaghoobi P, Nojeh A, Unusual secondary electron emission behavior in carbon nanotube forests. Scanning, 2009. 31(6) 221-228. 

Chikkaveeraiah BV, et al. Single-wall carbon nanotube forest arrays for immunoelectro-chemical measurement of four protein biomarkers for prostate cancer. Analytical Chemistry 2009 81 9129-34. http //dx.doi.oig/10.1021/ac9018022. 

Huynh, C.P., Hawkins, S.C., 2010. Understanding the synthesis of directly spimiable carbon nanotube forests. Carbon 48, 1105-1115. 

Leprd, X., Lima, M.D., Baughman, R.H., 2010. Spinnable carbon nanotube forests grown on thin, flexible metalUc substrates. Carbon 48, 3621-3627. 

Miao, M., 2013. Yam spun from carbon nanotube forests production, stmcture, properties and applications. Particuology 11, 378-393. 

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