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Objectives: Preparation of SWNTs and MWNTs Preparation of bamboo structure carbon nanotube Porosity control in carbon nanotubes Different size of carbon nanotubes High yield surface area of product Large-scale production
Introduction Carbon nanotubes are tubular forms of carbon that can be envisaged as graphitic sheets rolled into cylindrical form. These nanotubes have diameters of few nanometers and their lengths are up to several micrometers.
Each nanotube is made up of a hexagonal network of covalently bonded carbon atoms. Carbon nanotubes are of two types: single-walled and multi-walled. A single-walled carbon nanotube (SWNT) consists of a single graphene cylinder whereas a multi-walled carbon nanotube (MWNT) comprises of several concentric graphene cylinders.
Since their discovery in 1991by lijima. Carbon nanotubes have been of great interest both from a fundamental point of view and for future applications.
The most eye-catching features of these structures are their electronic. Mechanical optical and chemical characteristics which open a way to future applications. Different types of carbon nanotubes can be produced in various routs. The most common techniques used nowadays are : arc discharge, laser ablation,
chemical vapor deposition and flame synthesis. The property of carbon nanotube are as follows:  |  |
Process Description For production of carbon nanotube. chemical vapor deposition technique (CVD) is used .
CVD carbon nanotube synthesis is essentially a three-step process consisting of a catalyst
preparation step followed by the actual synthesis of the nanotube . the catalyst is generally
prepared by deposition of a transition metal (Co.Ni.Fe) onto a
substrate (SiO2, Zeolite, MCM, Metal Oxide, Al2O3) and then using different sources of
carbon (CH4C2 H 2,C2H4,CO) for decomposition of carbon , finally the products are
purified by different methods such as Oxidation , Acid treatment , Annealing ,
Ultra Sonication , Magnetic purification , micro filtration , cutting , functionalisation and
chromatography. 
Applications The most important application of our carbon nanotubes are: Catalyst support Batteries Fuel Cells: H2, Li storage Field emitters for instrumentation . capacitors Electrodes in electrochemistry CNT based microscopy: AFM , STM ... Nanotube sensors: force , pressure, chemical ... Diodes, transistors and capacitors Nanoscale reactors, ion channels Membranes for molecular transport Filling materials in polymer composites
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