Carbon nanotubes contaminants

Pulskamp, K., Diabate, S., and Krug, H.F. (2007) Carbon nanotubes show no sign of acute toxidty but induce intracellular reactive oxygen spedes in dependence on contaminants. Toxicology Letters, 168 (1), 58-74. 

Carbon nanotubes prepared by several methods are mixed with nanoparticles, amorphous carbon, fullerenes, and other contaminants [1576]. Nanotubes isolated from the mixture contain single-walled (SWNT) as well as multiwalled (MWNT) nanotubes. In general, the diameter of a SWNT is on the order of several nanometers, but the length can be several microns. Thus far, spectroscopic (mainly Raman) studies have been focused on SWNTs of small diameters (<2nm) that become metallic or semiconducting depending on their diameter and chirality. Chemical and physical... 

Wongchoosuk C, Wisitsoraat A, Tuantranont A, Kerdcharoen T. Portable electronic nose based on carbon nanotube-SnO(2) gas sensors and its apphcation for detection of methanol contamination in whiskeys. Sensor. Actual. B-Chem. 2010 147(2) 392-399. DOI 10.1016/j.snb.2010.03.072. 

Apul OG, Karanfil T. Adsorption of synthetic organic contaminants by carbon nanotubes a critical review. Water Res 2015 68 34-55. 

Fig. 26 (a) Near-field Raman image and (b) simultaneously obtained surface topography of single wall carbon nanotubes. Scan area is 1 x 1 xm Numerous circular features in the topography are attributed to contaminant water droplets. The cross-section profiles for Raman and topographic images are shown in panels c and d, respectively. Reprinted with permission of [87], copyright (2003) American Institute of Physics... 

Chen and co-workers [14] have produced carbon nanotubes using HEBM. They used graphite as precursor and milled it for about 150 h at ambient temperature, followed by a heat treatment at 1,400 °C for 6 h in a nitrogen atmosphere. The outer diameter of the resulting material was 20 nm. The main contaminants found in these carbon nanotubes were iron and chromium originated from the balls and the inner wall of the steel container. 

Upadhyayula, V. K., Deng, S., Mitchell, M. C., and Smith, G. B. (2009). Application of carbon nanotube technology for removal of contaminants in drinking water A review. Set Total Environ. 408(1), 1-13. 

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