3. Where does your imagination take you?
Figure 1.1:
Preface
Is nanotechnology the gateway to the
future for human beings on Earth?
4
4. Figure 1.3: Arnold Schwarzenegger’s character
mentions nanotechnology in “The Terminator 3”
movie.
“…its arsenal includes
nanotechnological
transjectors…It can control other
machines.”
Figure 1.2: A nanocar made from a single
molecule.
Emergence
5
6. Millimetre scale (1 m = 1000 mm)
ant and flea
• 5 mm
• 3mm
• 1mm
http://www.nation
alinsectweek.co.u
k/resources/buzz
_ant_06.pdf
www.nanotec.org.uk/report/chapter2.pdf
http://commons.wiki
media.org/wiki/File:D
rosophila_melanoga
ster_-
_front_(aka).jpg
7. Micrometre scale (1 mm = 1000 µm)
eye of a fruit fly and a red blood cell
• 400 µm
• 8 µm
http://www.molbio1.princeton.edu/facility/confocal/sem/imagelist1.html
www.mta.ca/dmf/blood.htm
9. Definition
“Nanotechnology is the understanding and control of matter at
dimensions of roughly 1 to 100 nanometers, where unique
phenomena enable novel applications.”
“Encompassing nanoscale science, engineering and technology,
nanotechnology involves imaging, measuring, modeling, and
manipulating matter at this length scale.”
National Nanotechnology Initiative, 2007
7
10. What is nano?
• Nanotechnology is science, engineering, and technology conducted at the nanoscale
(about 1 to 100 nanometers)
• Nano can refer to technologies, materials, particles, objects – we are focusing on
nanomaterials as these are already being used in workplaces more widely
• A sheet of paper is about 100,000 nanometers thick, a human hair is around 80,000-
100,000 nanometers wide
The Scale of the Universe video
Human hair and a sheet of
paper
12. Types of nanomaterials
• Nanomaterials can…
• occur naturally
• be produced by human activity
either as a product of another
activity
• on purpose (engineered)
• Our focus: engineered nanomaterials as
these are designed and integrated into
products because of the specific
characteristics of the nanomaterial
References:
https://nanohub.org/groups/gng/training_materials
(Introduction to Nanomaterials and Occupational
Health)
Images:
http://www.everychina.com/m-rubber-nano-zinc-oxide
http://img.docstoccdn.com/thumb/orig/76747818.png
http://www.nanodic.com/carbon/Fullerene/1_resize.jpg
http://www.carbonallotropes.com/39-122-thickbox/single-
wall-carbon-nanotubes.jpg
http://www.icbpharma.pl/techno_slow.html
Date, location
13. Why are nanomaterials used?
• At nano-scale,
• the material properties change - melting
point, fluorescence, electrical
conductivity, and chemical reactivity
• Surface size is larger so a greater
amount of the material comes into
contact with surrounding materials and
increases reactivity
• Nanomaterial properties can be ‘tuned’ by
varying the size of the particle (e.g. changing
the fluorescence colour so a particle can be
identified)
• Their complexity offers a variety of functions
to products
14. Examples of nanomaterials in
products
• Examples:
• Amorphous silica fume (nano-silica) in Ultra High
Performance Concrete – this silica is normally
thought to have the same human risk factors as
non‐nano non‐toxic silica dust
• Nano platinum or palladium in vehicle catalytic
converters - higher surface area to volume of
particle gives increased reactivity and therefore
increased efficiency
• Crystalline silica fume is used as an additive in
paints or coatings, giving e.g. self-cleaning
characteristics – it has a needle-like structure and
sharp edges so is very toxic and is known to
cause silicosis upon occupational exposure
Date, location
18. 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)
19. Different approaches to nanotechnology
Nanotechnologies can be:
• Top-down
• Two approaches used in producing nanotechnology systems. Top-
down method is used by computer chip manufacturers.
– Etching a block of material down to the desired shape
– Chips and processors
• Bottom-Up Approach:
• The bottom-up approach to nanomanufacturing is analogous to the
way biological systems are made. In biology, cells grow tissue,
organs, plants, hair, etc. through the process of self assembly. This
approach is now being studied in nanotechnology.
• Bottom-up
– Building materials atom by atom
– Nanoparticles such as C60, carbon nanotubes, quantum dots
– The top-down method is used by computer chip manufacturers.
The producers of chips begin the process with large bulk silicon
wafers and then manufacture the devices on top of them through
a series of printing, layering, doping and removal steps that
ultimately lead to a functional device. The printing is done
through a reduction process called photolithography. This
process has evolved since the 1960s, into one that is now
printing line width dimensions at the nanometer scale.
25. 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
31. Nanomaterials can be categorized into four types:
(1) Inorganic-based Nanomaterials: Metal and metal oxide
nanomaterials like Ag, Cu, Fe, ZnO
(2) Carbon-based Nanomaterials:Graphene, Carbon nanotubes,
carbon fiber
(3) Organic-based Nanomaterials: Formed from organic materials
excluding carbon materials, for instance, dendrimers, cyclodextrin,
liposome, and micelle
(4) Composite-based Nanomaterials: Combination of metal-
based, metal oxide-based, carbon-based, and/or organic-based
nanomaterials, and these nanomaterials have complicated structures
like a metal-organic framework
32. 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
