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An engineered DNA strand
What is Nanotechnology?
“Nanotechnology is the art an science of manipulating matter at
the nanoscale”
Buckyball
Nano technology is the study of making small microscopic things
It is an advance to the future2
0.22 m
Fullerenes C60
22 cm 0.7 nm
10 millions times smaller
1 billion times
smaller
What is Nanoscale?
12,756 km
1.27 × 107 m
0.7 × 10-9 m
3
2000 Years Ago – Sulfide nanocrystals used by Greeks and Romans to dye hair.
1000 Years Ago (Middle Ages) – Gold nanoparticles of different sizes used to produce different colors in stained glass windows.
1974 – “Nanotechnology” - Taniguchi uses the term nanotechnology for the first time.
1981 – IBM develops Scanning Tunneling Microscope. This microscope evolved to allow the manipulation of individual atoms and molecules in the field of Nano technology.
1985 – “Buckyball” - Scientists at Rice University and University of Sussex discover C60
1991 – Carbon nanotube discovered by S. Iijima
History of Nanotechnology
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NEED FOR NANOTECHNOLOGY
Allows the placement of small structures placed with precision,simplicity and low cost
Leads to economic growth
Enhances national security
Improves the quality of life
Leads to job creation5
Nanoscale Approaches and Fabrication
Top-down Approaches Bottom-up Approaches
Create smaller objects using Larger objects
They arrange smaller components in to more
complex.
Uses principles of molecular recognition
Layer-by-layer self assembly
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•Carbon NanoTubes
•Medicine
•Information Technology
•Nano Robots
•Energy
Nanotechnology Applications
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Stinger: Targeted Drug Delivery
Nano Transistor
•OLED
Nanorobot
AerogelNANO FILTERS
With NT, we can create unique materials and products which
are:
Stronger Lighter Cheaper Durable Precise
Computers can become a billion times faster and a million times smaller
Automatic Pollution Cleanup
Manufacturing at almost no cost
End of Illnesses (i.e. cancer, heart disease)
Universal Immunity (i.e. aids, flu)
Body Sculpting (i.e. change your
appearance)
IndustriaIndustriall
MedicalMedicalMaterialMaterial
AdvantagAdvantageses
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Carbon NanoTubes
The joining of two carbon nanotubes
Carbon Nanotubes:: This rotating picture is actually a model of carbon nanotube, the strongest and stiffest materials discovered till to date.CNTs also known as buckytubes are allotropes of carbon with a cylindrical nanostructure. Nanotubes have been constructed with length-to-diameter ratio of up to 132,000,000:1
carbon nanotube
15
Single Walled Nanotubes (SWNT)
The (n,m) nanotube naming scheme can be thought of as a vector (Ch) in an infinite graphene sheet that describes how to "roll up" the graphene sheet to make the nanotube.
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•Single-walled nanotubes have a diameter of close to 1 nanometer, with a tube length that can be many millions of times longer.
•The structure of a SWNT can be conceptualized by wrapping a one-atom-thick layer of graphite called graphene into a seamless cylinder.
•The way the graphene sheet is wrapped is represented by a pair of indices (n,m) called the chiral vector
•Single-walled nanotubes are an important variety of carbon nanotube because they exhibit electric properties
•There are two models of description of these MWNT::
In the Russian Doll model, sheets of graphite are arranged in concentric cylinders
In the Parchment model, a single sheet of graphite is rolled in around itself, resembling a scroll of parchment or a rolled newspaper
Multi Walled Nano Tubes (MWNT)
•Multi-walled nanotubes (MWNT) consist of multiple rolled layers (concentric tubes) of graphite
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Torus•A nanotorus is theoretically described as carbon nanotubes bent into a torus (doughnut shape). •Nanotori are predicted to have many unique properties, such as ‘magnetic moments’ which is the property of magnet that interacts with an applied field to give a mechanical moment
Nanobud•Carbon nanobuds are a newly created material combining two previously discovered allotropes of carbon: carbon nanotubes and fullerenes•This hybrid material has useful properties of both fullerenes and carbon nanotubes.
A stable nanobud structure
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Properties of Nano Tubes
•Strength :- Carbon nanotubes are the strongest and stiffest materials yet discovered in terms of tensile strength and elastic modulus respectively.
•Hardness:- The hardness of compressed SWNTs is 462–546 GPa, surpassing the value of 420 GPa for diamond
•Electrical:- In theory, metallic nanotubes can carry an electrical current density of 4 × 109 A/cm2 which is more than 1,000 times greater than metals such as copper.
•Thermal:- All nanotubes are expected to be very good thermal conductors along the tube, the temperature stability of carbon nanotubes is estimated to be up to 2800 °C in vacuum and about 750 °C in air.
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Striking properties of Striking properties of nanoparticles:nanoparticles:
Tremendous driving force for diffusionSemi conductionQuantization of electronic energy levelsHighly reactive
IMPLEMENTATIONS OF IMPLEMENTATIONS OF NANOTECHNOLOGYNANOTECHNOLOGY
Nano sensors Nano computersNano rodsI podsNanogears
•Solar cellsSolar cells developed at the New Jersey Institute of Technology use a carbon nanotube complex, formed by a mixture of carbon nanotubes and carbon buckyballs•UltracapacitorsWith a nanotube electrode the hollow spaces that store charge may be tailored to any size and consequently the capacity should be increased considerably.•Paper batteriesA paper battery is a battery engineered to use a paper-thin sheet of cellulose infused with aligned carbon nanotubes. The nanotubes act as electrodes; allowing the storage devices to conduct electricity. The battery, which functions as both a lithium-ion battery and a supercapacitor, can provide a long, steady power output comparable to a conventional battery.•Other applicationsCarbon nanotubes have been implemented in nanoelectromechanical systems, including mechanical memory elements (NRAM being developed by Nantero Inc.)
Applications of Nano Tubes
Aligned nanotubes are preferred for many
applications.
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APPLICATIONS OF APPLICATIONS OF NANOTECHNOLOGYNANOTECHNOLOGY
In curing diseases like AIDSTo make new surgical devicesChanging the untasteful medicine into
tastefulNano products can be prepared at
average sized homes
ADVANTAGES OF ADVANTAGES OF NANOTECHNOLOGYNANOTECHNOLOGY
Less pollutionLow production costMass production in food & consumablesTechnology itselfWarElectricity
• Health and safety issues Nanoparticles can cause serious illness or damage human body.Untraceable destructive weapons of mass destruction.
• Social & Political issuesCreates social strife through increasing wealth gap
Advisability of increasing scope of the technology creates political dilemma
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Implications of Nanotechnology
Exposure of human and the environment to nanomaterials at different stages of product life cycle
•“Grey-goo”It is a hypothetical situation where self replicating nanobots go out of control, and consume all matter on earth.
•Environmental issuesNanopollution is created by toxic wastes from nanomaterial manufacturingEnhances Global warming in the long run
“The Living Fog” formed by billions of replicating nanobots gone mad
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