(a) Single-walled carbon nanotubes (SWCNTs)—It is the type of the nanotube
having single layer and rolled up into the shape of the cylinder. The combination
of these nanotubes with the metals help in improving the properties such as
adsorption, mechanical, optical, electrical, etc. (Roman et al. 2010).
(b) Multiwalled carbon nanotubes (MWCNTs)—They are the multilayered structure having concentric cylinders placed with a distance of 0.34 nm. They are
used for eliminating the contaminants in water (Fig. 12.5).
Fig. 12.5 (a) Single-walled
carbon nanotubes. (b)
Multiwalled carbon nanotubes
(Ali, New Generation
Adsorbents for Water
Treatment, 2012)
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