2. FULLERENES
• Fullerence is third allotropic form of Carbon along with diamond and graphite . Fullerence are
made by heating of graphite in an electric arc in the presence of inert gas like Helium and Argon.
The sooty material formed by condensation of carbon vapor consists of mainly C60with smaller
amounts of C70 and traces of other forms.Fullerence are cage like molecules.C60 molecule has
a shape like soccer ball and called blackminster Fullerence.
3. • Fullerence contains 6 membered rings and 12 5 membered rings.A six membered ring is fused
with six membered ring or five membered rings.All carbon atom are equal and they have sp2
hybridized.Rach carbon atom forms three sigma bond with other three carbon atoms.
• The remaining electron at each carbon is delocalized in molecular orbital which give aromatic
character to molecule.The ball shaped molecules has 60 vertices,each occupied by one carbon
atom.It contains both single and double bonds with C-C distances of 143.5pm and 138.3pm
respectively..
4. PROPERTIES OF FULLERENES.
• Fullerenes are heat resistant.
• Insoluble in water but dissolve in comman solvents at room temperature.
• Highest tensile strength of any known 2D structure or element.
• Highest packing density of all known structures
• Impenetrable to all elements under normal circumstances,even to a helium atom with energy of
5ev.
5. APPLICATIONS OF FULLERENE:
• In optics : for electro graphical imaging,optical filters.
• In electronics : Used as molecular switches,diodes,transistors,resistors for lithography,magneto
optical recorders,photo electronic devices.
• Fullerene blended with polymers in organic photo voltaic.
• In medicines : for treatment of HIV, drug delivery,MRI, X-Ray imaging.
• As antioxidant,as catalyst,inWater purification.
6.
7. CARBON NANOTUBES
• Carbon nanotubes are allotropes of carbon with a cylindrical nanostructures,These are tubes
with diameters in nanoscale.Nanotubes are members of the fullerene structural family.Their
name is derived from their long,hallow structure with the walls formed by one-atom-thick sheets
of carbon, called graphines.
• These sheets are rolled at specific and discrete angles and the combination of the rolling angle
and radius decides the nanotube properties.
8. CATEGORIES OF NANOTUBES
SINGLE-WALLED NANOTUBES
(SWNTS)
• It is obtained by rolling a sheet of graphite
into a cylinder.
• Typical diameters of SWNTs are in the
range of 1-2nm and their length can be
several micrometers.
MWNTS(COAXIAL ASSEMBLY OF
SWCNTS)
• Individual nanotubes naturally align
themselves into“ropes”held together by
Vander waals forces.
• They have their diameters in the range of
2-25nm.
9. PROPERTIES OF NANOTUBES
• Carbon nanotubes have high termal conductivity.
• High electrical conductivity.
• High mechanical strength.
• High thermal stability.
• Enhanced chemical reactivity.
• Unique mechanical properties.
10. APPLICATIONS OF CARBON NANOTUBES
• In Field emitter/emission,energy storage(CNT emits electrons at high field).
• In conductive or reinforced plastics.
• In CNT based RAMs,transistors,fibers,ceramics.
• In biomedical applications(cancer therapy).
• CNT based fibres,fabrics and ceramics.
