carbon nano tubes

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CARBON NANO TUBES D.AKSHAYA B.TECH IT-A

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CARBON NANO TUBES

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Page 1: Carbon nano tubes

CARBON NANO TUBESD.AKSHAYAB.TECH IT-A

Page 2: Carbon nano tubes

WHAT ARE CARBON NANO TUBES?

An allotrope of carbon Allotrope- different structural form of the

same element(here carbon) Fullerene family-entirely made of carbon Rolled-graphene structures

Page 3: Carbon nano tubes

ALLOTROPES OF CARBON

carbon

Diamond Graphite Fullerene

Page 4: Carbon nano tubes
Page 5: Carbon nano tubes

DIAMOND AND GRAPHITE Diamond-carbon

atoms tetrahedrally linked covalent bonds in -3D

Hybridisation- sp3

Non-conductor

Graphite-Hexagonally linked carbon atoms

Hybridisation-sp2

Conductor-as it contains unpaired electrons

3

Page 6: Carbon nano tubes

FULLERENES They are molecules composed entirely

of carbon, which take the form of a hollow sphere, ellipsoid, or tube. Spherical fullerenes are sometimes called buckyballs, while cylindrical fullerenes are called buckytubes or nanotubes.

Page 7: Carbon nano tubes

BUCKY BALLSpherical in shape .A ball with 32 faces. Of the 32 faces, 12 pentagons and 20 hexagons . Looks exactly like a soccer ball(FOOTBALL)

Page 8: Carbon nano tubes

BUCKY TUBES Carbon nano tubes- name is derived from their size,

since the diameter of a nanotube is of the order of a few nanometers (1/50,000 times the width of a human hair) while they can be up to several centimeters in length

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TYPES OF CNT

No.of sheets rolled

•Single walled-CNT(SWNT)•Multi walled-CNT(MWNT)

Direction of rolling

•Zig-zag•Arm-chair•Chiral

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SWNT & MWNT SWNT-single

sheet of graphene

MWNT- multiple sheets of graphene rolled about a common axis(i.e concentric circles)

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ZIG-ZAG,ARMCHAIR &CHIRAL CNT

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PROPERTIESELECTRICAL

•The direction of rolling determines the electrical properties•Arm chair-metallic(conducting)•Chiral CNT- semiconducting•Generally CNT-1/3 metallic and 2/3 semiconducting properties in CNT•The band gap is inversely is proportional to its diameter (semiconducting CNT)

MECHANICAL

• The Young's modulus is over 1 Tera Pascal(Larger the young’s modulus, lesser is the stability)•It is stiff as diamond•The estimated tensile strength is 200 Giga Pascal•It is 10 times stronger than steel

OPTICAL

•Efficiently absorbs-uv,visible and IR rays-used in solar panels

•Absorption of electromagnetic waves especially microwaves helps enhancing stealth characteristics of military vehicles &aircrafts

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APPLICATIONS OF CNT Textiles-water proof &tear resistant

fabrics Combat jackets/body armour-bullet

proof wears Constructions-CNT bridges replacing

steel suspensions As super-conductors,diodes,transistors As capacitors-to increase charging

ability BUCKY PAPER-250 times stronger than

steel & 10 times lighter than it-used as “Faraday cage” to protect airplanes, electric devices

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FIELD OF MEDICINE Artificial muscles-sufficient contractility Scaffold materials for osteoblast

proliferation and bone formationOther uses: Air pollution filter Desalination of water-Reverse Osmosis POLYETHYLENE+CNT- elastic modulus >

30% Hydrogen storage 65% by weight

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GEODESIC-DOME-MONTREAL,CANADA

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THANK YOU!