nano structured materials.ppt
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Transcript of nano structured materials.ppt
Nano Structured materialsNano Structured materials
What are nano structured What are nano structured materials?materials?
1 Nanometer = 101 Nanometer = 10-9 -9 meters.meters. Materials with dimensions and tolerances in the Materials with dimensions and tolerances in the
range of 100 nm to 0.1 nmrange of 100 nm to 0.1 nm Metals, ceramics, polymeric materials, or Metals, ceramics, polymeric materials, or
composite materialscomposite materials One nanometer spans 3-5 atoms lined up in a One nanometer spans 3-5 atoms lined up in a
rowrow Human hair is five orders Human hair is five orders
of magnitude larger than of magnitude larger than nano materialsnano materials
History of NanomaterialsHistory of Nanomaterials 1974 The word1974 The word Nanotechnology Nanotechnology first coined by Nario first coined by Nario
Taniguchi, Univ. of Tokyo --- production technology to Taniguchi, Univ. of Tokyo --- production technology to get ultra fine accuracy and precision – 1nmget ultra fine accuracy and precision – 1nm
1981 IBM invented STM scanning tunneling microscope 1981 IBM invented STM scanning tunneling microscope which can move single atoms aroundwhich can move single atoms around
1985 new form of carbon discovered --- C60 1985 new form of carbon discovered --- C60 buckminister fullerene 60 carbon atoms arranged in a buckminister fullerene 60 carbon atoms arranged in a sphere made of 12 pentagons and 20 hexagonssphere made of 12 pentagons and 20 hexagons
Lycurgus chalice 4Lycurgus chalice 4thth Century A.D. Century A.D. Appears green in reflected light and Appears green in reflected light and red if light is directed through it (70 nm red if light is directed through it (70 nm particles of silver and gold in the glass)particles of silver and gold in the glass)
Lycurgus cup with diffused light
Lycurgus cup with focused light
History of History of NanomaterialsNanomaterials
Some possible applications of Some possible applications of Nano-materialsNano-materials
Nanomaterial CompositionNanomaterial CompositionComprised of many different elements Comprised of many different elements
such as carbons and metalssuch as carbons and metalsCombinations of elements can make up Combinations of elements can make up
nanomaterial grains such as titanium nanomaterial grains such as titanium carbide and zinc sulfidecarbide and zinc sulfide
Allows construction of new materials such Allows construction of new materials such as Cas C6060 (Bucky Balls or fullerenes) and (Bucky Balls or fullerenes) and nanotubesnanotubes
NATURE - Gecko PowerNATURE - Gecko Power
Gecko foot hairs typically have diametersof 200 – 500 nm. Weak chemical interaction between each hair and surface (each foot has over 1 million of these hairs) provides a force of10 N/cm2.
This allows Gecko’s to walk upside down across glass ceilings.
Bucky Balls (C60) were discovered in soot!
Nanoparticles in Smoke from Nanoparticles in Smoke from FiresFires
FerrofluidsFerrofluidsCoated Iron oxide nanoparticlesCoated Iron oxide nanoparticles
(wikipedia)
How they are madeHow they are madeClay/polymer nanocomposites can be Clay/polymer nanocomposites can be
made by subjecting clay to ion exchange made by subjecting clay to ion exchange and then mixing it with polymer meltsand then mixing it with polymer melts
Fullerenes can be made by vaporizing Fullerenes can be made by vaporizing carbon within a gas mediumcarbon within a gas medium
Bucky Ball (C60) C240 colliding with C60 at 300 eV (Kinetic energy)
Bucky Balls
http://www.pa.msu.edu/cmp/csc/simindex.html
Origin of the Bucky ballOrigin of the Bucky ball
Discovered in 1985 by Curl, Kroto, Discovered in 1985 by Curl, Kroto, and Smalley, for which they and Smalley, for which they received the Nobel Prize in 1996. received the Nobel Prize in 1996.
Fullerenes /Buckminsterfullerenes, Fullerenes /Buckminsterfullerenes, are named after Buckminster Fuller are named after Buckminster Fuller the architect and designer of the the architect and designer of the geodesic domegeodesic dome..
Bucky Ball propertiesBucky Ball properties Arranged in pentagons and hexagonsArranged in pentagons and hexagons Highest tensile strength of any known 2D Highest tensile strength of any known 2D
structure or element, including cross-section of structure or element, including cross-section of diamonds which have the highest tensile diamonds which have the highest tensile strength of all known 3D structures (which is strength of all known 3D structures (which is also a formation of carbon atoms)also a formation of carbon atoms)
Also has the highest packing density of all Also has the highest packing density of all known structures (including diamonds)known structures (including diamonds)
Impenetrable to all elements under normal Impenetrable to all elements under normal circumstances, even a helium atom with an circumstances, even a helium atom with an energy of 5eV (electron Volt) energy of 5eV (electron Volt)
Buckminsterfullerene usesBuckminsterfullerene uses Due to their extremely resilient and sturdy nature bucky Due to their extremely resilient and sturdy nature bucky
balls are debated for use in combat armorballs are debated for use in combat armor Bucky balls have been shown to be impervious to lasers, Bucky balls have been shown to be impervious to lasers,
allowing for defenses from future warfareallowing for defenses from future warfare Bucky balls have also been shown to be useful at Bucky balls have also been shown to be useful at
fighting the HIV virus that leads to AIDSfighting the HIV virus that leads to AIDS Researchers Kenyan and Wudl found that water soluble Researchers Kenyan and Wudl found that water soluble
derivates of Cderivates of C6060 inhibit the HIV-1 protease, the enzyme inhibit the HIV-1 protease, the enzyme responsible for the development of the virusresponsible for the development of the virus
Elements can be bonded with the bucky ball to create Elements can be bonded with the bucky ball to create more diverse materials including superconductors and more diverse materials including superconductors and insulatorsinsulators
Can be used to fashion nanotubesCan be used to fashion nanotubes
Nanotube propertiesNanotube properties Superior stiffness and strength to all other materialsSuperior stiffness and strength to all other materials Extraordinary electric propertiesExtraordinary electric properties Reported to be thermally stable in a vacuum up to 2800 Reported to be thermally stable in a vacuum up to 2800
degrees Centigrade degrees Centigrade Capacity to carry an electric current 1000 times better Capacity to carry an electric current 1000 times better
than copper wiresthan copper wires Twice the thermal conductivity of diamondsTwice the thermal conductivity of diamonds Pressing or stretching nanotubes can change their Pressing or stretching nanotubes can change their
electrical properties by changing the quantum states of electrical properties by changing the quantum states of the electrons in the carbon bondsthe electrons in the carbon bonds
They are either conducting or semi-conducting They are either conducting or semi-conducting depending on the their structuredepending on the their structure
Nanotube usesNanotube usesCan be used for containers to hold various Can be used for containers to hold various
materials on the nano-scale levelmaterials on the nano-scale levelDue to their exceptional electrical Due to their exceptional electrical
properties, nanotubes have a potential for properties, nanotubes have a potential for use in everyday electronics such as use in everyday electronics such as televisions and computers to more televisions and computers to more complex uses like aerospace materials complex uses like aerospace materials and circuitsand circuits
Carbon Based NanotubesCarbon Based Nanotubes
Applications of NanotechnologyApplications of Nanotechnology Next-generation computer chipsNext-generation computer chips
Ultra-high purity materials, enhanced thermal Ultra-high purity materials, enhanced thermal conductivity and longer lasting nanocrystalline conductivity and longer lasting nanocrystalline materialsmaterials
Kinetic Energy penetratorsKinetic Energy penetrators Nanocrystalline tungsten heavy alloy to replace Nanocrystalline tungsten heavy alloy to replace
radioactive depleted uraniumradioactive depleted uranium Better insulation materialsBetter insulation materials
Create foam-like structures called ‘aerogels’ from Create foam-like structures called ‘aerogels’ from nanocrystalline materialsnanocrystalline materials
Porous and extremely lightweight, can hold up to 100 Porous and extremely lightweight, can hold up to 100 times their weighttimes their weight
More applications…More applications… Improved HDTV and LCD monitorsImproved HDTV and LCD monitors
Nanocrystalline Nanocrystalline selenide, zinc sulfide, cadmium selenide, zinc sulfide, cadmium sulfide, and lead telluride to replace current sulfide, and lead telluride to replace current phosphorsphosphors
Cheaper and more durableCheaper and more durable Harder and more durable cutting materialsHarder and more durable cutting materials
Tungsten carbide, tantalum carbide, and titanium Tungsten carbide, tantalum carbide, and titanium carbidecarbide
Much more wear-resistant and corrosion-resistant Much more wear-resistant and corrosion-resistant than conventional materialsthan conventional materials
Reduces time needed to manufacture parts, cheaper Reduces time needed to manufacture parts, cheaper manufacturingmanufacturing
Still more applications…Still more applications… Greater fuel efficiency for carsGreater fuel efficiency for cars
Improved spark plug materials, ‘railplug’Improved spark plug materials, ‘railplug’ Stronger bio-based plasticsStronger bio-based plastics
Bio-based plastics made from plant oils lack sufficient Bio-based plastics made from plant oils lack sufficient structural strength to be usefulstructural strength to be useful
Merge nanomaterials such as clays, fibers and tubes Merge nanomaterials such as clays, fibers and tubes with bio-based plastics to enhance strength and with bio-based plastics to enhance strength and durabilitydurability
Allows for stronger, more environment friendly Allows for stronger, more environment friendly materials to construct cars, space shuttles and a materials to construct cars, space shuttles and a myriad of other productsmyriad of other products
Nanocomposites They are composites that consist of nanosized
particles embedded in some type of matrix This is a group of promising new materials. One type of nanocomposite is currently being
used in high performance tennis balls. These balls retain their original pressure and
bounce twice as long as conventional ones. Air permeation through the walls of the ball is
inhibited by a factor of two due to the presence of a flexible and very thin (10 to 50 ) nanocomposite barrier coating that covers the inner core.
Nano composite in high Nano composite in high performance Tennis Ballsperformance Tennis Balls
Because of their outstanding characteristics, these Double Core™ balls have recently been selected as the official balls for some of the major tennis tournaments.
This nanocomposite coating consists of a matrix of butyl rubber, within which is embedded thin platelets of vermiculite,5 a natural clay mineral.
The vermiculite platelets exist as single-molecule thin sheets—on the order of a nanometer thick
Within the butyl rubber, the vermiculite platelets are aligned such that all their lateral axes lie in the same plane; and throughout this barrier coating there are multiple layers of these platelets
DendrimersDendrimers
Dendrimer StructuresDendrimer Structures Dendrimers are nanostructures that can be precisely Dendrimers are nanostructures that can be precisely
designed and manufactured for a wide variety of designed and manufactured for a wide variety of applications. applications.
Dendrimers are the first large, man-made molecules with Dendrimers are the first large, man-made molecules with precise, nano-sized composition and well-defined three-precise, nano-sized composition and well-defined three-dimensional shapes.dimensional shapes.
Current polymer molecules are long, spaghetti-like Current polymer molecules are long, spaghetti-like strands that grow in only two directions. Dendrimer strands that grow in only two directions. Dendrimer molecules grow three-dimensionally by the addition of molecules grow three-dimensionally by the addition of shells of branched molecules to a central core. shells of branched molecules to a central core.
The cores are also spacious and have “sticky” points on The cores are also spacious and have “sticky” points on the outside to which various chemical units can be the outside to which various chemical units can be attached. attached.
By adjusting chemical properties of the core, the shells, By adjusting chemical properties of the core, the shells, and especially the surface layer, dendrimers can be and especially the surface layer, dendrimers can be tailored to fit the needs of specific applications.tailored to fit the needs of specific applications.
Characteristics of DendrimersCharacteristics of Dendrimers Dendrimer-based technologies provide exciting new interfaces Dendrimer-based technologies provide exciting new interfaces
between chemistry, biology and advanced materials. between chemistry, biology and advanced materials. Efficient membrane transport — Dendrimers have Efficient membrane transport — Dendrimers have
demonstrated rapid transport capabilities across biological demonstrated rapid transport capabilities across biological membranes. membranes.
High loading capacity — Dendrimer structures can be used to High loading capacity — Dendrimer structures can be used to carry and store a wide range of metals, organic or inorganic carry and store a wide range of metals, organic or inorganic molecules by encapsulation and absorption. molecules by encapsulation and absorption.
High uniformity and purity — The synthetic process used High uniformity and purity — The synthetic process used produces dendrimers with uniform sizes, precisely defined produces dendrimers with uniform sizes, precisely defined surface functionality, and very low impurity levels. surface functionality, and very low impurity levels.
Low toxicity — Most dendrimer systems display very low Low toxicity — Most dendrimer systems display very low cytotoxicity levels. cytotoxicity levels.
Low immunogenicity — Dendrimers commonly manifest a Low immunogenicity — Dendrimers commonly manifest a very low or negligible immunogenic response when injected or very low or negligible immunogenic response when injected or used topically. used topically.
Applications of DendrimersApplications of Dendrimers Applications of dendrimers are underway in Applications of dendrimers are underway in
materials engineering, industrial, materials engineering, industrial, pharmaceutical, and biomedical applications. pharmaceutical, and biomedical applications.
Specifically, nanoscale catalysts, novel Specifically, nanoscale catalysts, novel lithographic materials, rheology modifiers, lithographic materials, rheology modifiers, targeted drug delivery systems, MRI contrast targeted drug delivery systems, MRI contrast agents, and bioadhesives represent some of agents, and bioadhesives represent some of the potential applicationsthe potential applications
Nano-IntermediatesNano-IntermediatesNanostructured films, dispersions, high Nanostructured films, dispersions, high
surface area materials, and surface area materials, and supramolecular assemblies are the supramolecular assemblies are the high utility intermediates to many high utility intermediates to many products with improved properties products with improved properties such as solar cells and batteries, such as solar cells and batteries, sensors, catalysts, coatings, and drug sensors, catalysts, coatings, and drug delivery systems. delivery systems.