The design, characterization, and application of structures, devices, and systems by controlled manipulation of size and shape of materials at the nanometer scale (atomic, molecular, and macromolecular scale

1. Nanotechnology - Basics

2. What is Nanotechnology?
• The design, characterization, and application of structures, devices, and
systems by controlled manipulation of size and shape of materials at the
nanometer scale (atomic, molecular, and macromolecular scale) ,
• To produce materials with at least one novel/superior characteristic or
property.

3. Why Nanoscale?
•A nanometer (nm) is one thousand millionth of a
meter. People are interested in the nanoscale
because at this scale physical and chemical
properties of materials differ significantly from
those at a larger scale.

4. What is nanomaterial?
•Is defined as any material that has unique or novel
properties, due to the nanoscale ( nano metre- scale)
structuring.
•These are formed by incorporation or structuring of
nanoparticles.
•They are subdivided into nanocrystals, nanopowders, and
nanotubes: A sequence of nanoscale of C60 atoms
arranged in a long thin cylindrical structure.

5. Definition
• Most widely used definition:
• 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.

6. Nanometre scale (1 µm = 1000 nm) – viruses & DNA
• 50 – 100 nm • 2 nm
http://www.gala-instrumente.de/images/deben_
www.answers.com/topic/virus

7. What is nanomaterial?
carbon nanotubes

8. Nanostructures
• Fullerenes – e.g. carbon nanotubes and buckyballs

9. Carbon nanotubes
http://www.nano-lab.com/nanotube-imag

10. Carbon Nanotubes
• Commercially produced by companies such as Thomas Swan
• Desirable product
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11. Potential applications of carbon nanotubes
Materials & Chemistry
- Ceramic and metallic CNT composites
- Polymer CNT composites (heat conducting
polymers)
- Coatings (e.g. conductive surfaces)
- Membranes and catalysis
- Tips of Scanning Probe Microscopes (SPM)
Medicine & Life Science
- Medical diagnosis (e.g. Lab on a Chip (LOC))
- Medical applications (e.g. drug delivery)
- Chemical sensors
- Filters for water and food treatment
Electronics & ICT
- Lighting elements, CNT based field emission
displays
- Microelectronic: Single electron transistor
- Molecular computing and data storage
- Ultra-sensitive electromechanical sensors
- Micro-Electro-Mechanical Systems (MEMS)
Energy
- Hydrogen storage, energy storage (super
capacitors)
- Solar cells
- Fuel cells
- Superconductive materials

12. Carbon nanotubes
• Have raised concerns due to a superficial likeness to asbestos fibres
and extreme durability
• Potential exposures during manufacturing, processing, product use
and disposal
• Have been researched more than most manufactured nanostructures

13. Nanometre scale (1 µm = 1000 nm) – viruses & DNA
• 50 – 100 nm • 2 nm
http://www.gala-instrumente.de/images/deben_
www.answers.com/topic/virus

14. Nanostructures
• Nanoparticles

15. Nanostructures
• Quantum dots
http://www.nist.gov/public_affairs/update/quant
http://www.nanopicoftheday.org/2003Pics/QDRainbow.htm

16. Nanostructures
• Non-carbon nanotubes
• Nanowires
• Biopolymers
• Dendrimers

17. 1.1.2- What is nanomaterial?
Noble metal nanocrystals with cyclic
penta-twinned structures

18. 1.1.2- What is nanomaterial?
Naonpowder

19. •What is nanomaterial?
•Nanotubes are extremely strong mechanically
and very pure conductors of electric current.
•Applications of the nanotube
include resistors, capacitors, inductors, diodes
and transistors. ),.

20. What is nanomaterial?
•Nanomaterials are interesting because at the
small scale, materials have fundamentally
different properties than at the bulk due to
increased surface area to volume ratios.

21. What is nanomaterial?
Increased interaction and reactivity is one
of the by products of materials that are nanoscale,
which means potentially using less of the material
or that even on the nanoscale the properties are so
utterly different from that of the bulk scale.
•

22. •Nanomaterials’ Characteristics
Most of them are novel, why?
One definition of novel materials is:
(new forms of existing materials with
characteristics that differ significantly from
familiar or naturally-occurring forms.)
Nanomaterials can have one, two or three
dimensions in the nanoscale:

23. example
Category of nanomaterials
layers, multi-layers, thin films, platelets and surface
coatings. They have been developed and used for
decades, particularly in the electronics industry.
One-dimensional nanomaterials
nanowires, nanofibres made from a variety of
elements other than carbon, nanotubes and, a
subset of this group, carbon nanotubes.
Two-dimensional nanomaterials
are known as nanoparticles and include
precipitates, colloids and quantum dots (tiny
particles of semiconductor materials), and
Nanocrystalline materials
Three-dimensional nanomaterials
• Nanomaterials’ Characteristics

24. When Nanotechnology started
In some senses, nanoscience and
nanotechnologies are not new.
Chemists have been making polymers, which are
large molecules made up of nanoscale subunits, for
many decades and nanotechnologies have been
used to create the tiny features on computer chips
for the past 20 years.

25. When Nanotechnology started
However, advances in the tools that now
allow atoms and molecules to be examined
and probed with great precision have enabled
the expansion and development of
nanoscience and nanotechnologies.

26. Approaches of Nanotechnology
(growth methods ): Bottom-up or top-down?
•Bottom-up approaches seek to have smaller components
built up into more complex assemblies, while top-down
approaches seek to create nanoscale devices by using
larger, externally controlled ones to direct their assembly.
•The top-down approach often uses the traditional
workshop or micro-fabrication methods where externally
controlled tools are used to cut, mill, and shape materials
into the desired shape and order.

27. Bottom-up or top-down?
•Micropatterning techniques, such
as photolithography and inkjet printing belong to
this category.
•Bottom-up approaches, in contrast, use
the chemical properties of single molecules to
cause single-molecule components to
• (a) self-organize or self-assemble into some useful
conformation, or
•(b) rely on positional assembly.

28. Bottom-up or top-down?

29. 2- Applications of Nanotechnology:
2.1 General Applications
Examples
Application
Diagnostics, Drug delivery, Tissue engineering,
Cryonics
Medicine
Memory storage, Novel semiconductor devices,
Novel optoelectronic devices, Displays,
Quantum computers
Information and communication
Aerospace, Catalysis, Catalysis, Construction
Vehicle manufacturers
Heavy Industry
Foods, Household, Optics, Textiles, Cosmetics,
Sports
Consumer goods
Environment

30. 2.2- Environmental Applications
Check http://www.nanowerk.com/products/product.php?id=160 for more details
Examples
Application
Photocatalyst consisting of silica Nanosprings
coated with a combination of titanium dioxide
Carbon capture
Pollutants sensors that able to detect lower limits
with low cost
Sensors
Heavy metal decontaminant removes heavy metals
such as lead, cadmium, nickel, zinc, copper,
manganese and cobalt in a neutral pH environment
without using any form of sulphur .
Remediation (decontamination, oil spill
management)
Veolia Water Solutions & Technologies' ceramic
membrane modules, utilizing the CeraMem
technology platform, can be supplied with a variety
of inorganic microfiltration and ultrafiltration
membranes.
Wastewater treatment
Heat distribution e.g. ceramic-like
materials that provide sufficient reliability and
durability of the entire structure
Energy
Drinking water purification

31. Nanotechnology
What make technology at the
nanoscale different from technology
at the macroscale?

32. Volume to surface area ratio
• As objects get smaller they
have a much greater surface
area to volume ratio
2 cm cube has a
surface area of 24
cm2 and a
volume of 8 cm3
(ratio = 3:1)
10 cm cube has a
surface area of 600 cm2
and a volume of 1000
cm3 (ratio = 0.6:1)

33. Physical properties
• At very small sizes physical properties (magnetic, electric and optical)
of materials can change dramatically.

34. Applications
• Antibacterial effect of silver
www.nanotech-now.com

35. Applications
• Coatings - self-cleaning windows and stainproof clothing

36. Applications
• Microchips
•http://ion.asu.edu/cool66_IC2/cool66_ic_thumb.ht

37. Applications
• Sunscreens and cosmetics

38. Applications
• Catalysts
• Envirox™ cerium oxide
• Nanoremediation
• SAMMS technology to remove
mercury
• Paper
• photographic paper
• Filters
• nanofibres
• Toothpaste
• to remineralise teeth
• Food
• packaging
• Paint
• improved adhesion and anti-fungal
qualities/anti-graffiti
• Clothes
• non-staining and anti-radiation
• Batteries
• (Black & Decker) phosphate
nanocrystal technology
• Cleaning products

39. Why is there so much interest/concern about
nanotechnology?
• Enormous potential
• Huge gaps in knowledge concerning the possible risks
• Difficulty in detecting and removing
• Absence of regulation

40. Potentials risks associated with nanotechnology
• Adverse health effects in humans from deliberate or
accidental exposure
• Adverse effects on the environment from deliberate or
accidental exposure
• Potentially explosive properties of nanostructures
• “Grey goo”

41. Risk assessment problems
• Very difficult to detect without sophisticated equipment
• Difficult to predict how particles will behave in the environment
(dispersed/clumped)
• Small size may result in particles passing into the body more easily
(inhalation, ingestion, absorption)
• May be more reactive due to surface area to volume ratio
• Potential to adsorb toxic chemicals
• Persistence - Longevity of particles in the environment and body are
unknown