Carbon+Nanotubes+(John+Page)

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= = =Carbon and its many forms:= Carbon, the sixth element of the periodic table, appears in many different forms; some of which have only been discovered recently. -//Eight allotropes of carbon// Diamond is one of many allotropes of carbon, or one of the different forms of pure elemental carbon. Its atoms are arranged in a cubic crystal structure, called the diamond lattice. It has the highest hardness of any bulk material because of its strong covalent bonds. Diamond has been known of for thousands of years, but it was not proved to be carbon until 1772 when Antoine Lavoissier conducted an experiment in which diamond reacted with oxygen. He noted that the only product of the reaction was carbon dioxide, meaning that the only reactant other than the oxygen was carbon. - //Diamond// Graphite (which is commonly referred to as pencil "lead" due to the Latin misnomer 'plumbago' meaning "lead ore"), is a conductive, semimetal that is most commonly seen in pencils. It was named by Abraham Werner in 1789 and is the most stable form of carbon at standard temperature and pressure. Graphite is made of sheets of hexagonal carbon. //- Graphite// In 1956, carbon fibers were discovered which allowed for very lightweight, elastic objects to contain a lot of strength. Examples of things made with carbon fibers are sails for boats or tennis rackets.

-//Carbon Fiber (Woven)//

// In 1985, fullerenes (a.k.a. Bucky Balls) were discovered. These were named after Buckminster Fuller who invented the geodesic dome, a dome comprised of great circles on the surface of a sphere. Fullerenes have been used in the fields of electronics and materials sciences ////. // //- Buckminsterfullerene (Bucky Ball)//

Shortly after fullerenes were discovered, the term "graphene" came about, meaning a single-atom thick sheet of graphite. Graphene is a honeycomb lattice formation of carbon atoms, identical to the benzene ring, with a one-atom width; making it nearly two-dimensional. The isolation of graphene was important for modern technology because it has a number of capabilities and properties that have never been seen on Earth. For example, graphene is the fastest conductor of electricity at room temperature that has been discovered. - //Graphene//

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=Carbon Nanotubes:= In 1991, a physicist, named Sumio Iijima, who had been recently working for NEC Fundamental Research Lab as an electron microscopist, discovered carbon nanotubes; more specifically the multi-cylindrical wall formation (MWNT) of carbon nanotubes. The single walled form was isolated in 1993. Iijima described the nanotubes as "finite carbon structures consisting of needle-like tubes". Carbon nanotubes are small, cylindrical carbon structures made of hybridized carbon atoms -- carbon with atoms whose atomic orbitals have been mixed to produce new orbitals that will satisfy the desired bonding properties. There are few carbon nanotubes identical to each other; the electronic, thermal, and structural properties of these tubes vary dramatically based on the diameter, length, geometry, twist, and number of walls. There are two types of carbon nanotubes: The geometric shape of a SWNT is a nearly hexagonal lattice, however it is not exactly a hexagonal shape because the tube is bent into a cylinder. The MWMT has a multi-cylindrical wall, meaning that it consists of many SWNTs.
 * Single Wall Nanotube (SWNT)
 * Multi Wall Nanotube (MWNT)

- //Single Walled Carbon Nanotube (3D Rotation Structure)//

=Importance of Carbon Nanotubes:= Carbon Nanotubes are important in the development of modern technology because they have properties rarely seen together. They are many times stronger than steel, yet are much lighter and more flexible. They can also be incredible conductors of electricity.

=Chemical Explanation:= The carbon atoms hybridize to form a lattice like a cylinder made out of graphene. The geometry of the nanotube is what determines the properties of the nanotube. This is because different sizes and different shapes of nanotubes have different electron configurations. These electrons can make one nanotube a conductor and one nanotube a nonconductor. One of the most challenging problems for chemists to solve is how to grow nanotubes the same way each time. Nanotubes were first made by passing a high voltage through graphite, but this method is hard to control. Now carbon nanotubes are typically grown using chemical vapor deposition (CVD). CVD is a method that deposits carbon containing gas onto metals at high temperatures. Nobody fully understands why this method works.

=Carbon Nanotubes in Everyday Life:= Carbon nanotubes have been used and have the potential to be used in the following fields:
 * __Clothes:__**
 * Waterproof, tear-resistant attire
 * Combat jackets for the military (about twenty times the strength of Kevlar)
 * Stealth technology (low-observable technology)
 * __Electromagnetism:__**
 * Replacement for tungsten filaments in lightbulbs
 * Optical ignition (A layer of SWNT placed on top of explosives can be ignited with a camera flash)
 * Field Emission Displays (FED)
 * __Acoustic:__**
 * Loudspeaker (Carbon nanotubes generate sound in a way similar to thunder); electrical current causes nanotubes to vibrate, and this vibration causes sound.

Sources: [] [] [] [] [|http://www.personal.rdg.ac.uk/~scsharip/tubes.htm]