Nanotechnology:
From synthesis toApplications
Dr. Ashraf Elsayed
Associate Professor of Microbial Genetics
Botany Department, Faculty of Science, Mansoura University
2.
Nanoscience is thestudy of phenomena and manipulation of
materials at atomic, molecular and macromolecular scales,
where properties differ significantly from those at a larger scale
(novel properties).
Nanotechnologies are the design, characterisation,
production and application of structures, devices and systems
by controlling shape and size at nanometre scale.
Nanostructure is the Structure with at least one dimension
< 100 nm
Nanotechnology
3.
Meter- One thousandmillimeter .(103
mm)
Millimeter- One thousandth of meter.(10-3
m)
Micron: a micron is a millionth of a meter (10-
6
m) (or) one thousandth of millimeter
Nanometer: one thousandth of a micron (10–9
m)
(or) a billionth of a meter. ie.,one billion
nanometers in a meter.
What is a nanometer?
Why “Nano” isInteresting
• Particles are:
- small
– High surface-to-volume ratio
– React differently
– Act differently (new properties)
– Interact with light differently
– Are on the scale of small biological structures
10.
What make technologyat the nano-
scale different from technology at the
macro-scale?
11.
Volume to surfacearea 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)
12.
Nanomaterials have arelatively larger surface area when
compared to the same mass of material produced in a larger form.
Nano particles can make materials more chemically reactive and
affect their strength or electrical properties.
At the nanoscale, the physical, chemical, and biological
properties of materials differ in fundamental and valuable ways
from the properties of individual atoms and molecules or bulk
matter
13.
Optical Properties
Surface PlasmonResonance
– Interaction of light with metallic nanoparticle surfaces
– Coupling of free electrons and incident light
– Localized coherent oscillation of electrons
– Optical properties of nanostructures; depends on size, shape,
composition, and environment
• Nano-particles
• Nano-fibers
•Nano-tubes
• Nano-fluidies
Based on the size and shape, the Nano materials are
classified into:
Nanostructures or Nanomaterials
17.
Nanoparticles are classifiedinto two groups:
1. organic and 2. inorganic ones.
Organic nanoparticles consist of carbon nanoparticles
Inorganic nanoparticles contain:
•Magnetic nanoparticles
•Noble metal nanoparticles (like gold and silver)
•Semi-conductor nanoparticles (like titanium oxide and zinc
oxide)
Editor's Notes
#13 Schematic illustrating a localized surface plasmon on a metal
nanoparticle.
Figure that illustrates relationships between shape, architecture,
and composition (from top to bottom) on the optical properties of metal
nanoparticles (Au nanorods, nanoshells, and nanocages, respectively).
