introduction to nanoparticals along with properties and synthesis

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2. K.K.WAGH COLLEGE OF AGRICULTURAL
BIOTECHNOLOGY,NASHIK-03
(Affiliated to Mahatma Phule krushi vidyapith,rahuri)
TITLE - INTRODUCTION TO NANOPARTICALS
PRESENTED BY-
Apsunde Ganesh.N.
(BTN-2014/03)
UNDER GUIDENCE OF-
Prof.S.A.Patil
(Dept.of Agriculture Microbiology) 2

3. Contents
1. Introduction
2. Definition
3. History
4. Properties
4.1 variation in properties
5. Synthesis
5.1 Sol-gel
5.2 Ion implantation
6. Applications
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4. 1.Introduction
Nanoparticles are particles between 1 and 100 nanometres
(nm) in size with a surrounding interfacial layer. The
interfacial layer is an integral part of nanoscale matter,
fundamentally affecting all of its properties. The
interfacial layer typically consists of ions, inorganic and
organic molecules. Organic molecules coating inorganic
nanoparticles are known as stabilizers, capping and
surface ligands, or passivating agents. In nanotechnology,
a particle is defined as a small object that behaves as a
whole unit with respect to its transport and properties.
Particles are further classified according to diameter.
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5. 2.Definition
 A nanoparticle (or nanopowder or nanocluster or
nanocrystal) is a microscopic particle with at least one
dimension less than 100 nm.
 The term "nanoparticle" is not usually applied to
individual molecules; it usually refers to in organic
materials.
 Ultrafine particles are the same as nanoparticles and
between 1 and 100 nm in size, as opposed to fine
particles are sized between 100 and 2,500 nm, and coarse
particles cover a range between 2,500 and 10,000 nm
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6. 3.History
Although nanoparticles are associated with modern
science, they have a long history. Nanoparticles were
used by artisans as far back as Rome in the fourth
century in the famous Lycurgus cup made of dichroic
glass as well as the ninth century in Mesopotamia for
creating a glittering effect on the surface of pots.In
modern times, pottery from the Middle Ages and
Renaissance often retains a distinct gold- or copper-
colored metallic glitter. This luster is caused by a
metallic film that was applied to the transparent
surface of a glazing. The luster can still be visible if
the film has resisted atmospheric oxidation and other
weathering.
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7. 4.Properties
 Nanoparticles are of great scientific interest as they
are, in effect, a bridge between bulk materials and
atomic or molecular structures.
 A bulk material should have constant physical
properties regardless of its size, but at the nano-scale
size-dependent properties are often observed.
 Thus, the properties of materials change as their size
approaches the nanoscale and as the percentage of the
surface in relation to the percentage of the volume of
a material becomes significant 7

8.  For bulk materials larger than one micrometer (or micron),
the percentage of the surface is insignificant in relation to
the volume in the bulk of the material
 The interesting and sometimes unexpected properties of
nanoparticles are therefore largely due to the large surface
area of the material, which dominates the contributions
made by the small bulk of the material.
 Nanoparticles often possess unexpected optical properties
as they are small enough to confine their electrons and
produce quantum effects
EX.gold nanoparticles appear deep-red to black in sol.
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9.  Nanoparticles of yellow gold and grey silicon are
red in color & Gold nanoparticles melt at much
lower temperatures (~300 °C for 2.5 nm size)
 Semiconductor nanoparticle (quantum dot) of lead
sulfide with complete passivation by oleic acid,
oleyl amine and hydroxyl ligands (size ~5nm)
 A prototype nanoparticle of semi-solid nature is
the liposome. Various types of liposome
nanoparticles are currently used clinically as
delivery systems for anticancer drugs and
vaccines.
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10.  Nanoparticles of yellow gold and grey silicon are
red in color & Gold nanoparticles melt at much
lower temperatures (~300 °C for 2.5 nm size)
 Semiconductor nanoparticle (quantum dot) of lead
sulfide with complete passivation by oleic acid,
oleyl amine and hydroxyl ligands (size ~5nm)
 A prototype nanoparticle of semi-solid nature is
the liposome. Various types of liposome
nanoparticles are currently used clinically as
delivery systems for anticancer drugs and
vaccines.
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11. Nanoparticles are unique because of their large surface area
and this dominates the contributions made by the small bulk
of the material. Zinc oxide particles have been found to
have superior UV blocking properties compared to its bulk
substitute. This is one of the reasons why it is often used in
the preparation of sunscreen lotions.
 Nanoparticles are important scientific tools that have been
and are being explored in various biotechnological,
pharmacological and pure technological uses. They are a
link between bulk materials and atomic or molecular
structures.
 Nanoparticals absorb greater amount of solar radiation
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12. 1 kg of particles of 1 mm3 has the same surface area
as 1 mg of particles of 1 nm3
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13. 4.1.Variation in properties
 The chemical processing and synthesis of high-
performance technological components for the private,
industrial, and military sectors requires the use of high-
purity ceramics
 condensed bodies formed from fine powders, the irregular
particle sizes and shapes in a typical powder often lead to
non-uniform packing morphologies that result in packing
density variations in the powder compact.
 Uncontrolled agglomeration of powders due to attractive
van der Waals forces can also give rise to microstructural
heterogeneity
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14. In addition, any fluctuations in packing density in the
compact as it is prepared for the kiln are often amplified
during the sintering process, yielding inhomogeneous
densification.
Some pores and other structural defects associated with
density variations have been shown to play a detrimental
role in the sintering process by growing and thus limiting
end-point densities.
 The containment of a uniformly dispersed assembly of
strongly interacting particles in suspension requires total
control over interparticle forces. Monodisperse
nanoparticles and colloids provide this potential.
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15. Monodisperse powders of colloidal silica, for example, may
therefore be stabilized sufficiently to ensure a high degree
of order in the colloidal crystal or polycrystalline colloidal
solid that results from aggregation.
The degree of order appears to be limited by the time and
space allowed for longer-range correlations to be
established.
Such defective polycrystalline colloidal structures would
appear to be the basic elements of submicrometer colloidal
materials science and, therefore, provide the first step in
developing a more rigorous understanding of the
mechanisms involved in microstructural evolution in high
performance materials and components. 15

16. 5.Synthesis
 There are several methods for creating nanoparticles,
including
-Gas condensation
-Attrition
-Chemical precipitation
-Ion implantation
-Pyrolysis
-Hydrothermal synthesis
 In attrition, macro- or micro-scale particles are ground in a
ball mill, a planetary ball mill, or other size-reducing
mechanism. The resulting particles are air classified to
recover nanoparticles 16

17.  In pyrolysis, a vaporous precursor (liquid or gas) is forced
through an orifice at high pressure and burned. The resulting
solid (a version of soot) is air classified to recover oxide
particles from by-product gases.
Traditional pyrolysis often results in aggregates and
agglomerates rather than single primary particles.
A thermal plasma can deliver the energy to vaporize small
micrometer-size particles
The thermal plasma temperatures are in the order of 10,000
K, so that solid powder easily evaporates. Nanoparticles are
formed upon cooling while exiting the plasma region.
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18.  The main types of the thermal plasma torches used to
produce nanoparticles are dc plasma jet, dc arc plasma, and
radio frequency (RF) induction plasmas.
In the arc plasma reactors, the energy necessary for
evaporation and reaction is provided by an electric arc
formed between the anode and the cathode.
i. For example, silica sand can be vaporized with an arc
plasma at atmospheric pressure, or thin aluminum wires
can be vaporized by exploding wire method. The
resulting mixture of plasma gas and silica vapour can be
rapidly cooled by quenching with oxygen, thus ensuring
the quality of the fumed silica produced.
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19. 5.1. Material Processing by Sol-Gel Method
Introduction
 The sol-gel process is very long known since the late 1800s.
The versatility of the technique has been rediscovered in the
early 1970s when glasses where produced without high
temperature melting processes.
 Sol-gel is a chemical solution process used to make ceramic
and glass materials in the form of thin films, fibers or
powders.
 A sol is a colloidal (the dispersed phase is so small that
gravitational forces do not exist; only Van der Waals forces
and surface charges are present) or molecular suspension of
solid particles of ions in a solvent. 19

20. Sol-gel Processing
 The sol-gel process is a wet-chemical technique that uses
either a chemical solution (sol short for solution) or
colloidal particles (sol for nanoscale particle) to produce an
integrated network (gel).
 Metal alkoxides and metal chlorides are typical precursors.
They undergo hydrolysis and polycondensation reactions to
form a colloid, a system composed of nanoparticles
dispersed in a solvent.The sol evolves then towards the
formation of an inorganic continuous network containing a
liquid phase (gel).
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21.  Formation of a metal oxide involves connecting the metal
centers with oxo (M-O-M) or hydroxo (M-OH-M)
bridges, therefore generating metal-oxo or metal-hydroxo
polymers in solution.
 After a drying process, the liquid phase is removed from
the gel. Then, a thermal treatment (calcination) may be
performed in order to favor further polycondensation and
enhance mechanical properties.
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22. 5.2 Ion implantation
 Ion implantation is low-temperature process by
which ions of one element are accelerated into a solid
target, thereby changing the physical, chemical, or
electrical properties of the target.
 Ion implantation is used in semiconductor device
fabrication and in metal finishing, as well as in materials
science research.
 The ions can alter the elemental composition of the target
(if the ions differ in composition from the target) if they
stop and remain in the target. 22

23. General principle
 Ion implantation equipment typically consists of an ion
source, where ions of the desired element are produced,
an accelerator, where the ions are electrostatically
accelerated to a high energy, and a target chamber, where
the ions impinge on a target, which is the material to be
implanted. Thus ion implantation is a special case of
particle radiation.
 Each ion is typically a single atom or molecule, and thus the
actual amount of material implanted in the target is the
integral over time of the ion current. This amount is called
the dose. 23

24. The currents supplied by implanters are typically small
(microamperes), and thus the dose which can be implanted
in a reasonable amount of time is small. Therefore, ion
implantation finds application in cases where the amount of
chemical change required is small.
Typical ion energies are in the range of 10 to 500 keV (1,600
to 80,000 aJ). Energies in the range 1 to 10 keV (160 to
1,600 aJ) can be used, but result in a penetration of only a
few nanometers or less.
Energies lower than this result in very little damage to the
target, and fall under the designation ion beam deposition.
Higher energies can also be used: accelerators capable of 5
MeV (800,000 aJ) are common. 24

25. An ion implantation system at LAAS technological facility in Toulouse, France.
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26. 6. Applications
Nanoparticle Applications in Medicine
• The use of polymeric micelle nanoparticles to liver drugs to
tumors.
• The use of polymer coated iron oxide nanoparticle to break up
clusters of bacteria, possibly allowing more effective treatment
of chronic bacterial infections.
• The surface change of protein filled nanoparticles has been
shown to affect the ability of the nanoparticle to stimulate
immune responses. Researchers are thinking that these
nanoparticles may be used in inhalable vaccines.
• chemotherapy drugs attached to nanodiamonds to treat brain
tumors. 26

27. Nanoparticle Applications in Manufacturing and
Materials
• Silicate nanoparticles can be used to provide a barrier to
gasses (for example oxygen), or moisture in a plastic film
used for packaging. This could slow down the process of
spoiling or drying out in food.
• Zinc oxide nanoparticles can be dispersed in industrial
coatings to protect wood, plastic, and textiles from
exposure to UV rays.
• Silicon dioxide crystalline nanoparticles can be used to fill
gaps between carbon fibers, thereby strengthening tennis
racquets.
• Silver nanoparticles in fabric are used to kill bacteria,
making clothing odor-resistant. 27

28. Nanoparticle Applications and the Environment
• Researchers are using photocatalytic copper tungsten
oxide nanoparticles to break down oil into biodegradable
compounds. The nanoparticles are in a grid that provides
high surface area for the reaction, is activated by sunlight
and can work in water, making them useful for cleaning up
oil spills.
• Researchers are using gold nanoparticles embedded in a
porous manganese oxide as a room temperature catalyst to
breakdown volatile organic pollutants in air.
• Iron nanoparticles are being used to clean up carbon
tetrachloride pollution in ground water
• Iron oxide nanoparticles are being used to clean arsenic
from water wells. 28

29. References
https://en.wikipedia.org/wiki/Nanoparticle
https://www.slideshare.net/DanishKurien/nanopart
icles
https://www.sciencedaily.com/terms/nanoparticle.
htm
https://www.nature.com/subjects/nanoparticles
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