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TRANSCRIPT
KİM 736
Nanostructured Films
Prof.Dr.Ümit DEMİR
Nanotechnology has been used at a very old days.
It is not a new technology!
4th Century AD
Made by nanocomposite material
Green due to reflection
Red and purple due to transmitted
light
Glass with 66% Ag, 31%Au and 3%
Cu nanoparticles (20-40 nm)
embedded into glass
Nature 2000, 407, 691
Lycurgus Cup,
Stained
Glass
9th-17th Centuries:
Glowing, glittering “luster” ceramic
glazes used in the Islamic world, and
later in Europe, contained silver or copper
or other metallic nanoparticles.
Glazes
containing
copper and
silver
nanoparticles
Damascus (Şam) Saber
extraordinary strong and sharp
CNT
HRTEM
Nature 444, 286, 2006
Cementite Fe3C
nanowires encapsulated by carbon
nanotubes
The use the nanomaterials is not new
However, being nanoscientist is new
Because,
Pyhsics and Chemistry behind the nanoworld
have not been understood until to this day
1857: Michael Faraday discovered colloidal “ruby” gold, demonstrating that
nanostructured gold under certain lighting conditions produces different-
colored solutions.
Historical Perspectives
Image 1 Print of Faraday lecturing, taken from the Illustrated
London News; 1856. Amongst the crowd (front centre) is Prince
Albert.
M. Faraday, 'The Bakerian lecture: experimental relations of gold (and other metals) to light', Philosophical
Transactions of the Royal Society of London, Vol. 147 (1847), 145-181, p. 159.
This has now led to the strong emergence of the nanoscience of gold and nanotechnology.
Faraday concluded that the ruby fluid was
gold dispersed in the liquid in a very finely
divided metallic form not visible in
any of the microscopes available in his
day.
Faraday was the first to realise the cause.
1914, Richard Adolf Zsigmondy was an
Austrian-Hungarian chemist. He was known for
his research in colloids, for which he was
awarded the Nobel Prize in chemistry in 1925.
He made a detailed study of gold sols and other
nanomaterials with sizes down to 10 nm using
an ultramicroscope which was capable of
visualizing particles much smaller than the light
wavelength. Zsigmondy was also the first to use
the term "nanometer" explicitly for characterizing
particle size. Zsigmondy, R. (1914). Colloids and the
Ultramicroscope. New York: J.Wiley and Sons.
Retrieved 10 May 2011.
The first observations and size measurements
of nanoparticles had been made during the first
decade of the 20th century by Richard Adolf
Zsigmondy.
Irving Langmuir
Langmuir Blodgett trough
1920: Nobel Prize in Chemistry, Irving Langmuir, winner of the 1932 Nobel Prize
in Chemistry, and Katharine B. Blodgett introduced the concept of a monolayer, a
layer of material one molecule thick.
pressuree.g., stearic acid
monolayer filmwater
hydrophilic end
hydrophobic end
A monolayer film (single layer of molecules)
Homework 1
Design an experiment
that enable us to measure
the thickness of a
monolayer of stearic acid
1959 - Richard Feynman - Nobel Prize in Physics
•“There’s plenty of room at the bottom” - an invitation
to enter a new field of physics
•Offered two $1000 prizes:
– Build an electric motor in a 1/64 inch cube
– Reduce a page of a book by a factor of 25,000;
read using an electron microscope
•1960 - engineer claimed the first prize
•1985 - graduate student wrote a page from A Tale of
Two Cities 1/160 millimeter in length using e-beam
lithography
I would like to describe a field, in which little has been done, but in which an
enormous amount can be done in principle. This field is not quite the same as
the others in that it will not tell us much of fundamental physics (in the sense of,
"What are the strange particles?") but it is more like solid-state physics in the
sense that it might tell us much of great interest about the strange phenomena
that occur in complex situations. Furthermore, a point that is most important is
that it would have an enormous number of technical applications.
What I want to talk about is the problem of manipulating and controlling things
on a small scale.
1965, Moore’s Law describes a trend of technology. It states that the number
of transistors that can be put on a single chip will double every two years.
Memristor and Graphen ?????
• Physical limitation at a 0.016 micron process
– 16 nanometers
– Smaller than this quantum effects begin
to take over, electronics becomes
unpredictable
– If Moore’s Law continues to hold, we’ll hit
16nm in 2018
1974; The Japanese scientist Norio Taniguchi of the Tokyo
University of Science used the term "nano-technology" in a 1974
conference, to describe semiconductor processes such as thin film
deposition and ion beam milling exhibiting characteristic control on
the order of a nanometer. His definition was, "'Nano-technology'
mainly consists of the processing of, separation, consolidation, and
deformation of materials by one atom or one molecule.
1974, ALD was introduced by Dr. Tuomo Suntola and co-workers in
Finland to improve the quality of ZnS films used in electroluminescent
displays.
1981, Often described as “the founding father of nanotechnology”, Eric Drexler
introduced the concept in his seminal 1981 paper in the Proceedings of the National
Academy of Sciences, which established fundamental principles of molecular
engineering and outlined development paths to advanced nanotechnologies.
GREY GOO?
The Drexler-Smalley
debate on molecular
assembly
1985: Rice University researchers Harold Kroto, Sean O’Brien,
Robert Curl, and Richard Smalley discovered the
Buckminsterfullerene (C60), more commonly known as the
buckyball, which is a molecule resembling a soccerball in shape
and composed entirely of carbon, as are graphite and diamond.
The team was awarded the 1996 Nobel Prize in Chemistry for
their roles in this discovery and that of the fullerene class of
molecules more generally.
1981, Scanning Tunnelling Microscope(STM) invented. Gerd Binning and Heinrich
Rohrer were awarded the 1986 Nobel Prize in Physics for their work. STM was a vital
tool necessary for ‘seeing’ and manipulating at the nanometre scale. The STM ‘sees’
by measuring mechanical forces of atoms, rather than by using light or electrons like
earlier microscopes.
1986, Gerd Binnig, Calvin Quate, and Christoph Gerber invented the Atomic Force
Microscope (AFM), which has the capability to view, measure, and manipulate
materials down to fractions of a nanometer in size, including measurement of
various forces intrinsic to nanomaterials.
1991:
Sumio Iijima of NEC is credited with discovering the
carbon nanotube (CNT), although there were early
observations of tubular carbon structures by others as
well. Iijima shared the Kavli Prize in Nanoscience in
2008 for this advance and other advances in the field.
CNTs exhibit extraordinary properties in terms of
strength, electrical and thermal conductivity, among
others.
1993:
Moungi Bawendi of MIT invented a method for
controlled synthesis of nanocrystals (quantum
dots), paving the way for applications ranging
from computing to biology to high-efficiency
photovoltaics and lighting. Within the next
several years, work by other researchers such
as Louis Brus and Chris Murray also contributed
methods for synthesizing quantum dots.
2000:
President Clinton launched the National Nanotechnology Initiative (NNI) to coordinate
Federal R&D efforts and promote U.S. competitiveness in nanotechnology. Congress
funded the NNI for the first time in FY2001. The NSET Subcommittee of the NSTC
was designated as the interagency group responsible for coordinating the NNI.
2004:
SUNY Albany launched the first college-level education program in nanotechnology
in the United States, theCollege of Nanoscale Science and Engineering
2004:
The European Commission adopted the Communication “Towards a European
Strategy for Nanotechnology ” COM(2004) 338, which proposed institutionalizing
European nanoscience and nanotechnology R&D efforts within an integrated and
responsible strategy, and which spurred European action plans and ongoing funding
for nanotechnology R&D.
2004:
Britain’s Royal Society and the Royal Academy of Engineering published
Nanoscience and Nanotechnologies: Opportunities and Uncertainties advocating the
need to address potential health, environmental, social, ethical, and regulatory issues
associated with nanotechnology.
2006:
James Tour and colleagues at Rice University built a nanoscale car made of
oligo(phenylene ethynylene) with alkynyl axles and four spherical C60 fullerene
(buckyball) wheels. In response to increases in temperature, the nanocar moved
about on a gold surface as a result of the buckyball wheels turning, as in a
conventional car. At temperatures above 300°C it moved around too fast for the
chemists to keep track of it!
2009:
Nadrian Seeman and colleagues at New York University created several DNA-like
robotic nanoscale assembly devices.
2010:
IBM used a silicon tip measuring only a few nanometers at its apex (similar to the
tips used in atomic force microscopes) to chisel away material from a substrate to
create a complete nanoscale 3D relief map of the world one-one-thousandth the
size of a grain of salt—in 2 minutes and 23 seconds. This activity demonstrated a
powerful patterning methodology for generating nanoscale patterns and structures
as small as 15 nanometers at greatly reduced cost and complexity, opening up new
prospects for fields such as electronics, optoelectronics, and medicine.
The first two-dimensional
material
What is Graphene?
One Man’s Junk, Another Man’s
Gold
STM piezo calibration
2D hexagonal
Van der Walls
forces
sp2
0.142 nm
0.335 nm
It was generally believed that 2D materials
were thermodynamically unstable and could
not exist.
A. K. Geim & K. S. Novoselov. The rise of graphene. Nature Materials Vol 6 183-191 (March 2007)
“The mother of all graphitic forms”
• Nanoscience is the study of phenomena and manipulation of
materials at atomic, molecular and macromolecular scales,
where properties differ significantly from those at a larger scale.
• Nanotechnologies are the design, characterisation, production
and application of structures, devices and systems by
controlling shape and size at nanometre scale.
An emerging, interdisciplinary science involving
Physics
Chemistry
Biology
Engineering
Materials Science
Computer Science
➢Nanoscience is not physics,
chemistry, engineering or biology. It is
all of them.
Interdisciplinary
Technology
New technologies and products: ~$1 trillion/year by 2015
Materials beyond chemistry: $340 B/y
Electronics: over $300 B/y
Pharmaceuticals: $180 B/y
Chemicals (catalysts): $100 B/y
Aerospace: ~$70 B/y
Tools: ~$22 B/y
New jobs: ~2 million nanotechnology workers
Nanotechnology Applications
Information Technology Energy
Medicine Consumer Goods
• Smaller, faster, more
energy efficient and
powerful computing
and other IT-based
systems
• More efficient and cost
effective technologies for
energy production− Solar cells
− Fuel cells
− Batteries
− Bio fuels
• Foods and beverages−Advanced packaging materials,
sensors, and lab-on-chips for
food quality testing
• Appliances and textiles−Stain proof, water proof and
wrinkle free textiles
• Household and cosmetics− Self-cleaning and scratch free
products, paints, and better
cosmetics
• Cancer treatment
• Bone treatment
• Drug delivery
• Appetite control
• Drug development
• Medical tools
• Diagnostic tests
• Imaging
Health Care
Making Repairs to the Body
• Nanorobots are imaginary, but nanosized delivery systems could…
– Break apart kidney stones, clear plaque from blood
vessels, ferry drugs to tumor cells
− Nanoparticles containing drugs are coated
with targeting agents (e.g. conjugated
antibodies)
− The nanoparticles circulate through the blood
vessels and reach the target cells
− Drugs are released directly into the targeted
cells
Abraxane
Drug: Paclitaxel
Chemotherapy for breast cancer
Approved in 2005 ($134 million in sales that year)*
Chemotherapeutic bound to protein nano-particle
doxorubicin
Chemotherapy agent for ovarian cancer
AmBisome
Doxil
amphotericin B
antifungal infections for cancer
patients
Targeted Drug Delivery
Nano Carriers
Thermal ablation of cancer cells assisted by nanoshells coated with metallic layer and an external
energy source – National Cancer Institute
− Nanoshells have metallic outer layer and silica core
− Selectively attracted to cancer shells either through a phenomena called enhanced
permeation retention or due to some molecules coated on the shells
− The nanoshells are heated with an external energy source killing the cancer cells
Thermal ablation of cancer cells
Health Care: Growing Tissue to Repair Hearts
• Nanofibers help heart muscle grow in the lab
– Filaments ‘instruct’ muscle to grow in orderly way
– Before that, fibers grew in random direction
Cardiac tissue grown with the help of nanofiber filaments
Health Care: Detecting Diseases Earlier
Early tumor detection,
studied in mice
Quantum dots
glow in UV light
– Injected in mice,
collect in tumors
– Could locate as
few as 10 to 100
cancer cells
The nanoscale cantilever detects the
presence and concentration of various
molecular expressions of a cancer cell – A. Majumdar, Univ. of Cal. at Berkeley
Nanotechnology offers tools and techniques for
more effective detection, diagnosis and
treatment of diseases
Detection and Diagnosis
• Lab on chips help detection and diagnosis of
diseases more efficiently
• Nanowire and cantilever lab on chips help in
early detection of cancer biomarkers
Protective nanopaint for cars
– Water and dirt repellent
– Resistant to chipping and
scratches
– Brighter colors, enhanced gloss
– In the future, could change color
and selfrepair?
Nanopaint on buildings could reduce
pollution
– When exposed to ultraviolet light,
titanium dioxide (TiO2) nanoparticles in
paint break down organic and inorganic
pollutants that wash off in the rain
– Decompose air pollution particles like
formaldehyde
Buildings as air purifiers?
Mercedes covered with tougher, shinier nanopaint
Energy
] 200 nm
Nano solar cells mixed in
plastic could be painted on
buses, roofs, clothing
– Solar becomes a cheap
energy alternative!
Grätzel cell for
photovoltaic generation
and water splitting
COLD SIDE
HOT SIDE
Thermoelectrics Devices
Power Generation
Refrigeration
I N P
I I
Cold Side
Hot Side
Dif
fus
ion
NASA Ames nanotechnology
Current CD and
DVD media have
storage scale in
micrometers
New nanomedia
1,000,000
times greater
storage density
in total
Technology: A DVD That Could
Hold a Million Movies
Nanoscience Biomimicry We’ve looked at ways scientists are attempting to mimic the
wonders of nanoscience in nature:
•sticky “feet”
•strong spider silk
•water collecting beetle backs
•self-cleaning light reflecting butterfly wings
•optical nanoscience
•and the list could go on and on.
•tough and light toucan beaks
Nano-Finger Tips Allow Geckos to Stick
http://robotics.eecs.berkeley.edu/~ronf/Gecko/index.html
Geckos Walk on Walls
A Material Stronger than Steel and More Elastic than Nylon?
For 450 million years, spiders have made silk, protein-based nanomaterials that self-assemble into fibers and sheets.
•If we figure out how to copy this nanscience feat, scientists would like to use the material to create an elevator to space.
http://www.newscientist.com/article.ns?id=dn3522
Butterfly wings are layers of nanoparticles
seperated by layers of air. The thickness of
the layers changes the colors that we see.
Living LED’s
Fluorescent patches on the wings of this
African swallowtail butterflies work in a
very similar way to high emission light
emitting diodes (LEDs).
Wings are Colorful and Hydrophobic!
•The nanostructure of
toucan beaks inspires automotive
panels that could protect
passengers in crashes.
• And inspires construction of
ultralight aircraft components.
Toucan Beaks
Toucan Beaks absorb high-energy impacts.
Living in the desert the thirsty Namib beetle collects dew to drink using nanodots on its back.
Thirsty people in Chile and Haiti
go to ridgetops to collect fog on
large sheets on ridgetops.
Thirsty ?
Lotus Effect
251793-gifmedia.mp4
Nano = Greek for dwarf (cüce, bodur)
1 nm = 10-3 mm =10-6 mm =10-9 m
1 nm =10 Å
NANO SCALE
1.27 × 107
m
ww
.ma
thw
ork
s.c
om
0.22 m 0.7 × 10-9 m
Fullerenes C60
12,756 Km22 cm 0.7 nm
10 millions times
smaller
1 billion times
smaller
ww
w.p
hysic
s.u
cr.
edu
What is Nanoscale
DNA
Close-up views at
progressive magnification
of our skinwhite blood cell
skin
atoms
nanoscale
There are enormous
length scale differences
in our universe!
At different scales
Different forces
dominate.
Different models better
explain phenomena.
Forces and Scale
cm : Gravity, Friction
mm : Gravity, Friction, Electrostatic
µm : Electrostatic, van der Waals,
Brownian
nm : Electrostatic, van der Waals,
Brownian, Quantum
Å : Quantum
At different scales Different forces dominate.
Particle Shape and The Surface
Simple geometric progression
from successive division of a
parent cube
1m
6 m2 (1 cube) →12 m2 (8 cubes) → 24 m2 (64 cubes) → 48 m2
(512 cubes) → 96 m2 (4096 cubes) → ………..
What will be the total surface area if these cubes are made to be
1 nm on a side
Volume of nanocube = (1x10-9 m)3 = (1x10-27 m3)
Surface area of nanocube = (1x10-9 m)2 x 6 = 6x10-18 m2)
Number of nanocubes per cubic meter = 1m3/(1x10-27 m3)
=1x1027 nanocubes
Total surface area =
(1x1027 nanocubes) x (6x10-18 m2)/nanocube= 6x109 m2 = 6 000
km2
The total surface area of the nanocubes is a billion
times that of the 1-m cube
Compare !!! Erzurum valley= (825 km²)
Given the same volume, the extend of the surface area depends
on the shape of material
A simple example is a sphere and a cube having the same volume
The cube has a larger surface area than the sphere
For this reason in nanoscience not only the size of a nanometerial is
important, but also its shape
The ratio between h and d determines whether a shape is like a wire or a disc
As particles get smaller, their
surface area to volume ratio gets
larger. Therefore, the ratio of
Surface atoms/Volume (bulk)
artom significantly increases.
Surface atoms/Volume atoms
One of the principal physical
differences between nanostructures
and bulk (macro) structures is that
there is a large number of
ions/atoms/species on the surface of
a nanostructure
SO WHAT?
Regardless of whether we consider a bulk material or a nanoscale material,
its pysical and chemical properties depend on a lot on its surface properties
As surface to volume ratio increases
A greater amount of a substance comes in
contact with surrounding material.
In contact with 3 atoms
In contact with 7 atomsMelting Point:
Surface atoms require less energy to
move because they are in contact with
fewer atoms of the substance.
• Manifestation of novel phenomena and properties, including
changes in:
- Physical Properties (e.g. melting point)
- Chemical Properties (e.g. reactivity)
- Electrical Properties (e.g. conductivity)
- Mechanical Properties (e.g. strength)
- Optical Properties (e.g. light emission)
Atoms and molecules that exist at the surface or at an interface are different from
the same atoms or molecules that exist in the interior of a material. This is true for
any material. Atoms and molecules at the interface have enhanced reactivity and a
greater tendency to agglomerate.
Surfaces atom and molecules are unstable, they have high surface area
Surface energy of two separate cubes is higher than
the surface energy of the two cubes agglomerated
Nanoparticles have a strong tendency to agglomerate. To avoid that,
surfactants can be used. This also explains why when nanoparticles are used
in research and industry they are often immobilised.
Surface Energy
Why a small water drop is sphere in shape?
Example of Gold Nano particle:
➢ Sphere of radius 12.5 nm contains total approx. 480,000 atoms.
surface contains approx. 48,000 atoms.
So, approx. 10% atoms are on the surface.
➢ Sphere of radius 5 nm contains total approx. 32,000 atoms.
surface contains approx. 8000 atoms.
So, approx. 25% atoms are on the surface.
Surface atoms have unused electrons – so very reactive
(can be used for catalysis)
Al13: Icosahedral rather than FCC (bulk)
• Decrease in binding energy to 2.77eV from 3.39eV
• Decrease in Al separation to 2.814A from 2.86A
In <6.5nm: face-centered cubic rather than face-centered
tetrahedral ( >6.5nm)
Mostly related with surface properties…
Au<5nm: icosahedral rather than FCC (bulk)
Structural Effect
MORE
Melting Point
Kelvin effect
Vapor pressure
Solubility
Ostwald ripening
Phase transition temperatures
Sintering temperatures…
Thermal conductivity () ↑ size↓
Electrical conductivity
Optical properties
Heat Capacity (Cv) ↑ size↓
Ferromagnetic properties
Mechanical properties
Super capacitors
..........
Chemical (catalytic) Properties
- Surface activity;
Bulk < plane surface < edge < corner
Quantum confinement results from electrons and holes being squeezed into a
dimension that approaches a critical quantum measurement, called the exciton
Bohr radius.
Quantum Confinement
For a semiconductor the
dimension should be less than the
Bohr exciton radius.
For magnetic material, the
dimension should be less than the
size of magnetic domain.
Toxicity
Nano-weapons
Grey GOO
Unknown risks
Potential Risks of Nanotechnology