Transcript and Nanotechnology

Introduction to Nanotechnology
Dr. Kamal K. Taha
Associate Professor of Physical Chemistry
Dean CAIS
U of B
Definition
 Nanotechnology,
shortened
to
“nanotech”, is the study of the
controlling of matter on an atomic
and molecular scale. Generally
nanotechnology deals with structures
sized between 1 to 100 nanometer in
at least one dimension and involve
developing materials or devices
within that size.
How small is Nano - small?
Units in nanometers (µm)
Compared to Human Hair
A Human Hair is about 100,000µm wide
At small size physical observation simply
changes. It is no longer governed by the
classical picture.
Nano-structures & Sensitivity
 As objects are scaled down the
ratio of the surface to volume
increases sharply. This makes
surface
effects
more
pronounced.
 Isolated small size electrode will
possesses high sensitivity due to
non-linearity effects.
Chemical Synthesis
LOW temperature methods Hydrothermal
chemical growth of ZnO
Different Nano-structrures Obtained by
controlling the reaction parameters
Nanotechnology spans many Areas
Information
Technology
Biotechnology
Mechanical
Mechanical
Eng.
Engineering
&
/
Robotics
Transportation
Advance
Materials &
Textiles
NANOTECHNOLOGY
National
Security &
Defense
Energy &
Environment
Aerospace
Medicine /
Health
Food and
Agriculture
Nanosized Iron for Groundwater Remediation:
Smaller sized iron particles More complete reduction
of chlorinated hydrocarbons
Absorbents for selective removal of pollutants
• Teabag catalysts for de-stenching
• Use high surface area Cu-ZnO catalysts to
absorb S - compounds
Treatment &
Remediation
End-of-pipe management and
cleanup of pollution
Iron Treatment Walls…
Used in groundwater treatment for many
years.
Iron chemically reduces organic and
inorganic environmental contaminants.
Currently involves granular or “microscale”
iron ( 50 mm or 50,000 nm).
and Nanotechnology
Nanosized iron enhances the reaction.
Enhanced further by coupling with other
metals (Fe/Pd)* on the nanoscale.
Nano Fe0 is more reactive and effective than
the microscale.
Smaller size makes it more flexible -penetrates difficult to access areas.
* Elliot and Zhang ES&T 2001, 35, 4922-4926
“Sense and Shoot”
Approach to Pollution
Treatment
Dual role of ZnO semicondouctor
film as a sensor and photocatalyst
Nanosized zinc oxide (ZnO) “senses” organic
pollutants indicated by change in visible emission
signal.
The ZnO “shoots” the pollutants via
photocatalytic oxidation to form more
environmentally benign compounds.
>300 nm
UV
Sensing capability means that the energyconsuming oxidation stage only occurs when the
pollutants present.
Multifunctionality and “smartness” is highly
desirable for environmental applications.
Kamat, P.V, et al. J.Phys.Chem. B 2002, 106,788-794.
Drug Delivery
Targeting Ligands
Liposome's
Governments Expenditure in Nanotech.
 Western Europe
 Japan
 U. S. A.
 Asia
: USD 669 Million
: USD 810 Million
: USD 774 Million
: USD 800 Million
Acknowledgements
 TOKTEN-Sudan;
 Dr. Omer Nor;
 Institute for Technical Research –NCR
 Omdurman Ahlia University
 Future university
 University of Elneelain