الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Nanotechnology is a collective definition referring to every technology and science which operates on a nanoscale and to the scientific principles and new properties that can be found and mastered when operating in this range. In the nanoscale, which is normally seen as going from 100 nm and down to just a few nanometers, the materials have properties that can be very different from those at a larger scale. A nanometer (nm) is one thousand millionth of a meter, 10-9.
Nanoparticles (NPs) are particles with less than 100 nm in one dimension. They have different physical, chemical, electrical and optical properties than those that occur in bulk samples of the same material. Different types of NPs have been synthesized such as carbon-based NPs, metal NPs, metal oxide particles, quantum dots, organic polymers and liposomes. Carbon-based NPs include fullerenes, graphene nanofoils, carbon nanotubes (CNTs), carbon nanofibres, carbon black (CB) and carbon nanofoams.
The first CNTs were prepared by M. Endo in 1978 in France. They are mainly classified into two types depending upon the structure: single walled carbon nanotubes (SWCNTs) and multiwalled carbon nanotubes (MWCNTs). The outer wall of pristine CNTs is chemically inert and this is not always desirable for applications. Functionalization of CNTs extends their properties and consequently their application potentials. There are two main methods to increase the solubility of CNTs: one is covalent functionalization where CNTs are covalently modified with functional groups on the surface and the other is a non-covalent functionalization approach which involves physical adsorption of small molecules or polymers onto the surface of CNTs.