The Role of Synthesis in Materials Technology

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The Role of Synthesis in Materials Technology

• 28th April 2008
• Childrens Club Lecture

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And he said unto them, it is not for you to know
the times or the seasons, which the Father hath
put in his own power. The Holy Bible (The Acts
17) My times are in thy hand. The Holy Bible
(Psalm 3115) To every thing there is a season,
and a time to every purpose under the heaven A
time to be born, and a time to die a time to
plant, and a time to pluck that which is
planted A time to kill, and a time to heal a
time to breakdown, and a time to build up A time
to weep, and a time to laugh a time to mourn,
and a time to dance A time to cast away stones,
and a time to gather stones together a time to
embrace, and a time to refrain from embracing A
time to get, and a time to lose a time to keep,
and a time to cast away A time to rend, and a
time to sew a time to keep silence, and a time
to speak A time to love, and a time to hate a
time of war, and a time of peace. The Holy Bible
(Ecclesiastes 31-8)
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Noahs Ark The Technological Marvel

• And God said unto Noah, The end of all flesh is
  come before me
• for the earth is filled with violence through
  them
• and, behold I will destroy them with the earth.
• Make thee an ark of gopher wood rooms shalt
  thou make in
• the ark, and shalt pitch it within and without
  with pitch.
• 15. And this is the fashion which thou shalt
  make it of The length of
• the ark shall be three hundred cubits, the
  breadth of it fifty cubits,
• and the height of it thirty cubits.
• A window shalt thou make to the ark, and in a
  cubit shalt thou
• finish it above and the door of the ark shalt
  thou set in the side
• thereof with lover, second, and third stories
  shalt thou make it.
• The Holy Bible (Genesis 6 13-16)

http//www.noahsark-naxuan.com/arkmodel.htm
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• Meteorite Iron Use 4000 BC
• Bronze Age Begins 1800 BC
• Wrought Iron Use 1500 BC
• Iron Age Begins 1000 BC
• Cast Iron Use 400 BC
• Synthetic rubber 1929/1930
• Nylon Introduced 1939
• Teflon Coatings 1960
• Fullerene Production - 1990

Time line illustrating the use of materials
during the past 10, 000 years
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Some Benefits from Materials Technology
Mailing services, Measuring instruments, Modem,
Network/cable television, Periodicals, News
papers, Over head projectors, Photocopy
machines, Play ground equipment, Radio,
Refrigerators, Slide Projectors, Scanner,
Search Engines, Switching technology,
Telephones, Transparencies, Type writers,
Video cameras, Vedio conferencing
Audio tapes, audio tape players, audio tape
recorders, calculators, cameras, compact disks
(CDs), CD players, Barcode, Colour Printers,
Computers, Digital video disk (DVD),
Electronic commerce, E-mail, Internet, Fax
machines, Laboratory equipment, Laser printers,
Laser pointers, Liquid crystal display, LCD ,
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What is new in Materials Technology?
The Living Cell is the All Time Marvel of
Almighty God, The Creator. Goal of Materials
Technology - To design and synthesize the
material with artificial intelligence that
replicate Living Cell in all aspects. The
Living Cell can apparently handle enormous number
of unimaginable, uncomprehendable and difficult
problems (functions) with ease and spontaneity.
multiple functions performed simultaneously by
The Living Cell Reproduction, Growth, Defense,
Protein synthesis, Transport of nutrients,
Information storage, Site directed information
transfer, Communication, Energy conversion and
Energy storage, Sensing All vital functions for
the sustenance of life takes place in the living
cells. Thus the Living Cells are
self-replicating, self-containing and
self-maintaining.
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The Living Cell Some questions to ponder on!

• What is the Living Cell?
• What does a Cell mean?
• Where does the term Cell originate from?
• How can the Living Cell be multifunctional and
  versatile?
• What is the structure of the Cell?
• What are the dimensions of the Living Cell?
• What are the constituents of the Cell?
• Can the Living Cells be mimicked?
• Can such mimics of the Living Cells act as
  molecular machines and
• revolutionize Materials Technology? If so in
  what way?
• How cells form complex organisms?
• The queries are recurring.

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The Living Cells Some Facts

• The Cell is the basis of life.
• The Cell is the smallest unit of all living
  organisms
• Organism can be unicellular (eg., bacteria) or
  multicellular
• 
  (eg., human beings).
  
• Human beings have an estimate of 100 trillion
  (1014) cells.
• A typical cell is of 10 µm size and 1 nanogram
  mass
• Latin word Cellula means a small room.
• Originator of the term Cell - Robert Hooke
• Important contribution of Robert Hooke to
  Biology
• His
  book Micrographia published in 1665

Robert Hooke (18th July 1635 3rd March 1703)
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I could exceedingly, plainly perceive it to be
all perforated and porous, much like a
honey-comb, but that the pores, or cells, ..
were indeed the first microscopical pores I ever
saw, and perhaps, that were ever seen, for I had
not met with any Writer or Person, t hat had made
any mention of them before this ..
Robert Hooke
(a)
(b)
(a) Title page of Micrographia (1665) (b) Robert
Hookes drawings of the cellular structure of
cork (plant tissue) and a spring of sensitive
plant from Micrographia
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The Living Cell - Compartmentalization
Schematic representation of a eukaryotic cell and
its compartments
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Living Cell An Inspiration to Advanced
Technologies

• Can we imagine a data storage device of
  micrometer (10-6 m)
• size but can squeez the data equivalent of five
  high-density floppy
• disks (5 x 1.44 MB 7.2 MB) ?
• Can we imagine a motor that is running on and on
  and on
• but only of size measuring a few hundredths of a
  thousandth
• of a millimeter?
• Can we imagine a catalyst capable of converting
  the inert
• nitrogen gas from the air into nitrogen
  fertilizer at room
• temperature and atmospheric pressure?
• Can we dream of the synthesis of natural
  products with 100
• enantiomeric excess (ee)?

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The Lesson Weak interactions are the best!

• Interactions that stabilize the
• local structures in proteins
• Hydrogen bonds (secondary structure),
• (b) disulfide bridges
• (tertiary or even Intermolecular,
• (c) salt bridges,
• (d) hydrophobic interaction.

The oval shape symbolizes the hydrophobic area
from which water is excluded
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Technologies of the New Millennium

• Information technology
• Nanotechnology and
• Biotechnology

Information technology

• The Beginning of Information Technology The
  Age of the Printed Book
• Johannes Gutenberg (1397 1468) Printing
  Technology

A copy of the 42-line Holy Bible
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Advent of Computers and Internet Information
Explosion

• But how could this happen?
• What is the driving force for such a drastic
  explosion in
• information technology?

• The new synthetic strategies that facilitated
  miniaturization
• of electronic elements and circuits
• Results of Miniaturization of electronic
  circuits
• Saving space
• Saving materials
• Enhanced memory capacity
• Cost effective,
• Efficient and
• Faster

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NANOTECHNOLOGY
Nanotechnology - Taniguchi at the University of
Tokyo, Japan, in 1974.
On 29th of December, 1959, Richard P. Feynman
took the shiny example of the living cell to
drive home his point that individual atoms can
be arranged in the way we want them to be. With
this ultimate degree of miniaturization all the
information contained in all the books in the
world can be stored in the grain of a sand.
Living cell is not only capable of storing
enormous amount of information in a very small
volume but also equipped with the hard ware to
read out the information and retrieve the same
when needed and put the same into action. In an
analogous way Richard P. Feynman professed that
it should be possible to write the entire
Encyclopaedia Britannica onto the point of a
needle. In those days when computers were huge
machines the wiring of which filled the whole
room completely, he is genius enough and fore
sighted to profess that computers of the future
should be made of wires that would only be 10 or
100 atoms in diameter.
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Nanotechnology - size matters
Nanoscience refers to the world as it works on
the atomic or molecular scale, from one to
several hundred nanometers. Nanometer 10-9
meters roughly the size of 10 hydrogen atoms
lined up or the width of DNA.
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Size comparisons of nanocrystals with bacteria,
viruses and molecules
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Graphite   More 2D like  sp2 Orbitals Strong
bonds within layers and weak bond between
layers Good conductor of electricity
Diamond   More 3D like behavior sp3
orbital Strong covalent bonding in 3
dimensions Bad electrical conductor   
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A Schematic representation of the structures of
graphite, diamond and fullerenes
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Simple representation of Nanocarbons
with PECULIAR Morphologies
Shekar Subramoney, Advanced Materials, 10,
1998, 1157
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Approaches for the synthesis of Nanostructured
Materials
Nanostructured Material
top-down
bottom-up
Assemble from Nano-building Blocks Power/aerosol
compaction Chemical Synthesis
Sculpt from Bulk Mechanical attrition (ball
milling) Lithography/etching
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Synthetic Strategy that lead to the formation of
Fullerenes

• A football (the C60 molecule is supposed to have
  the structure
• formed when each vertex on the seams of such a
  ball is replaced
• by carbon atm, (b) Schematic diagram of the
  pulsed supersonic
• nozzle used to generate carbon cluster beams

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Formation of Fullerenes - Synthetic Strategy

• Synthetic Strategy for the formation of
  Fullerenes
• Synthesis of Fullerene Derivatives
• Exohedral compounds
• Endohedral
• Intercalation Compounds

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Carbon Nanotubes

• Carbon nanotubes are a key component of
  nanotechnology

• Challenges ahead
• (a) Synthesis of carbon nanotubes
• with desired properties
• in large
• (b) Successful utilization of CNTs for a variety
  of Technologies
• remove the impurities present
• (c) Develop synthetic strategies
• for exclusive production of SWNTs or MWNTs
• (d) Making nanotubes soluble is also a note
  worthy problem.

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Carbon Nano test tube
The nano sized tubular carbon Rolled hexagonal
graphene sheets with fullerene
caps at both
ends
Hollow carbon tube - As a nano-scale test tube
for doing chemistry
As a mold for making nano rods of other
materials
Storage material
Magnetic and Electronic applications Difficult
task - Handling because of size
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Nano tube Seamless cylinders rolled up from
graphene sheet
Graphene Sheet
Single walled nano tube
Fig. Hexagonal net work of carbon atoms rolled
upto make a seamless cylinder
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Types of carbon nano tubes
Schematic representation of the relation between
nanotube and graphene
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Carbon Nanotubes An Evolution in Synthetic
Strategies

• Arc-discharge or vaporization process
• (in the presence of transition metal catalyst)
• Laser-evaporation of graphite
• (Laser furnace process)
• Chemical Vapour Deposition, CVD
• (Catalytic Pyrolysis of hydrocarbons) or
• Catalytic Chemical Vapour Deposition (CCVD)
• 4. Template Carbonization Method

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The Arc-Discharge Process
Schematic representation of the apparatus used
for the synthesis of CNTs
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The Arc-Discharge Process
Exclusive Synthesis of SWNTs
Arc discharge chamber with a web of SWNTs
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TEM images of various CNTs
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Laser Furnace Process
Laser-furnace (vaporization) apparatus
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Chemical Vapour Deposition
Experimental set up for Chemical Vapour
Deposition Synthesis, (b) probable models of CNT
growth
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4. Template Carbonization Method
Synthesis of carbon nanotubes by template
carbonization method
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Can a carbon source as common as kerosene be
used for the synthesis of nanoforms of carbon
materials?


(a)
(b)
(c)
SEM (scanning electron microscope) images of (a)
hair like fibers, (b) bitter gourd - like
rough fibers and (c) carbon thin film grown on a
stainless steel substrate
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Synthesis of loaded (metal(s)) carbon nanotubes
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Carbon Nanotubes as STM and AFM Tips
The invention of a very high definition
microscope called a scanning tunnelling
Microscope by Russell D. Young, in 1971, has
revolutionized the field of Nanotechnology. This
microscope is an instrument like a blindfolded
person feels the surface and scan atom by atom.
In this way it is possible to create an image of
any particular surface on atomic scale. Not long
after this invention it will be possible to
manipulate atoms in this Way.
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Carbon Nanotubes as STM and AFM Tips
STM image of quantum dot formed by
self-assembling (Ge pyramid)

• Scanning tunneling microscope (STM) image of a
  pyramid of germanium
• atoms on top of a silicon surface

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Role of Synthesis in Leather Technology
Synthetic strategy for Bronopol
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Biomimicking Lotus Leaf Microstructures

• Dream of human beings Creation of clothes that
  clean themselves
• Self cleaning clothes
• Two main concepts Design surfaces that can
  break down, decompose dust
• Produce
  surfaces with repellent properties
• Common route Treat target surface with self
  cleaning coatings
• Self cleaning coatings Hydrophilic and
  hydrophobic
• Hydrophilic coatings Window glass
• Cement
• Textiles
• Paints
• Self
  cleaning clothes
• Self cleaning clothes - Titania nanoparticles
• Potential hazards with titania nanoparticle
  films
• Surfaces with extreme water repellent properties
  are known in Nature
• Super hydrophobic nature of lotus leaves lotus
  leaf effect or self cleaning effect

Youyang Liu, J. Mater. Chem., 17 (2007) 1071
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Fig. 10. (a) top view of a lotus leaf (bar 50
mm). (b) Magnified section of the lotus leaf from
(a) (bar 5 mm). (c) Magnified view of a papilla
from (b) (bar 1 mm). (d) SEM image of the
bottom surface of the lotus leaf from (a) (bar
1 mm).
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Morphology of Lotus leaves Vs Carbon nanotube
clusters
(1)
(2)
Fig. 11. (1) Magnified vew of Papilla of Lotus
leaf, (2) SEM image of MWNTs deposited on silicon
wafer (bar 1 µm)

• Carbon Nanotubes are ideal candidates for the
  fabrication of artificial lotus leaves
• Carbon nanotube clusters with micro-nano binary
  structures form a good mimic of
• lotus leaves

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Self cleaning coating Lotus leaf effect
Dispersion of CNTs in water with ultrasonic
treatment
Dip cotton fabrics Into CNTs suspension
Deposit/adsorb CNTs to Cotton faber surface
Procedure for coating cotton fibres
with carbon nanotubes
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Self cleaning coating Lotus leaf effect
Dispersion of CNTs in water with ultrasonic
treatment
Dip cotton fabrics Into CNTs suspension
Deposit/adsorb CNTs to Cotton faber surface
Procedure for coating cotton fibres with carbon
nanotubes
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Fuel Cell Applications
Transportation
Industry Power Plants
Residential
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• Conclusion
• The living cells are versatile in its design and
  function.
• They provide all necessary inspiration to design
  and synthesize
• new materials with specific functions that bring
  about revolutions
• in Technology and also give birth to Advanced
  Technologies.
• Understanding and imitation of natural machinery
  of the
• living cells holds great rewards.
• But such endeavours are not free from barriers
  and obstacles.
• For instance, molecular level details of the
  working of ribosomes
• (their function of protein synthesis) is unclear
  even today and
• remains one of the hardest problems in biology.
• Therefore our knowledge and understanding of the
  processes
• going on in a living cell and also the
  mechanochemical functions
• of various cell components is limited.
• Any improvements in such an understanding
  facilitate imitation
• and mimicking of the synthetic strategies
  involved in life process
• (a unique network of chemical reactions).
• This knowledge will in turn bring about drastic
  changes and
• advancements in Materials Technology.