Tugas nanotechnology

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Nanoteknologi

Introduction
The Nature of Nanotechnology

Definitions of nanotechnology are
easy to find, but hard to agree on.
 Most of literature simply say
that nanotechnology considers
materials and architectures on
the nanoscale
 In some of the definitions it is
stated that nanotechnology
dealings mainly with structures
in the region between 1 and
100 nm.
 In any case, the dimension
plays the dominant role.
What is Nanotechnology?

Most of the currently known nano-effects are still deeply rooted in nanoscience, that is we
cannot speak at all of a technology. A careful differentiation will be put forward, not just
between science and technology, but also with the usual intermediate step, called
(nano)engineering. The development of a technique from a scientific finding never happens
in a single step.
From Nanoscience to Nanotechnology
Nanoscience, nanoengineering and
nanotechnology are represented
by three steps following each
other. Each step contains several of
very many possible examples,
which will help to realize how
nanoscience develops into
nanotechnology.

Structured Surfaced
It has long been known that
structured surfaces change the
physical and chemical properties of
the corresponding material. Two
property changes dominate the
interest in structured surfaces are:
 Change in wettability
 Change in optical properties
Technologies on the Nanoscales
Sketch of the gas–liquid–solid three-phase system.
(a) Water droplet on a smooth surface resulting in small contact
angles y
(b) On a nanostructured surface with increased y value
(c) On a bimodal micro/nano structured surface with the
largest contact angle.

Since the 1980s a slew of new instruments and manufacturing processes have emerged that
enable scientists and engineers to see that is, measure and manipulate at the nanolevel. It is
because of these that nanoengineering is emerging as a commercial endeavor.
Nanotool and Nanomanufacturing
Top-down manufacturing processes
 Products are designed using macrolevel
materials. To put it perhaps a little crudely,
one whittles away at the material until nano-
level features can be achieved.
 While the whittling process is, of course, as
old, even perhaps older, as mankind, this
process does not inherently produce
nanoscale structures.
 Its ability to do so depends on the material
being used and especially on the tools being
used. Much of the commercial nanotechnology
today can be traced back to better tools that
“sculpt” at the nanoscale.
Bottoms-up approaches
 products and materials are created one molecule at a
time.
 Nanotechnologists are practical people and must make
do with the current generation of manufacturing
technology, which is not especially bottoms up in
nature.
 Also, manufacturing one molecule (or atom) at a time
can sometimes be as painfully slow as it sounds, yet
again another drag on the potential for real business
opportunities.

Application of
Nanotechnology
Photovoltaic Manufacturing

Nanotech & Energy
Nanotechnology Could make energy
supply lean, green and mean
-Headline of the article on
azanano.com website-
 The energy industry has a crisis all its own, however, often
presented as a shortage of energy. The portrayal is based primarily
on the theory that much of our energy comes from fossil fuels and
that we are quickly running out of those fuels.
 Presenting the opportunities for nanotechnology in the energy
sector as largely defined by supposedly dwindling petroleum
reserves is likely to lead to an underestimation of the
opportunities and perhaps to misunderstandings about what
those opportunities actually are.
 Instead, not so much that nanotechnology can help us provide new
and better sources of energy, although, in fact, this is the case, but
rather that nanotechnology can provide us with new ways to
concentrate energy and deliver it to the places where it is needed
are the key word.
Scientific View

Nanotech & Energy
Position of
Opurtunity in
Value Chain
Likely Contribution of Nanotechnology
Extraction Nano-enabled enhancements can lead to reductions in the cost of extracting fuels from
fossil deposits thereby increasing the available reserves.
Nanocatalysts and Nano-enhanced drills are two areas where there is some obvious
potential.
Nanoengineering may also provide better ways of harnessing renewable energy
sources, especially better materials for windmills, solar power collectors, etc.
Transformation It is all about generating useful power from raw energy, simply making more efficient/
less polluting hydrocarbon fuels from raw fuels using nanocatalysts, for example.
Electricity appears to be the most useful form of power known and it is important to
remember that its all about how to generate electricity.
Storage Electricity is stored in batteries and nanotechnology is certainly making contributions
to enabling more efficient battery technology.

Nanotech & Energy
Position of
Opurtunity in
Value Chain
Likely Contribution of Nanotechnology
Distribution Long-haul transport of electricity is not outstandingly efficient and there is much
room for improvement.
Highly conductive nanomaterials, especially carbon nanotubes, offer hope for the
future here.
Usage by
Consumer
Nanomaterials can help in a number of ways to reduce the costs of energy at the
consumer level.
Better insulation using nanomaterials, Additives to fuel oil that make them
produce more energy per unit volume or mass, High-efficiency heating systems
using nanomaterials is yet another.
Nanosensors could also play an important role in conserving energy in buildings,
by providing finely tuned power monitoring and control.

Impact Nanotechnology on Energy Sector
Based on the technology directions currently being taken by both R&D
efforts and corporate commercialization programs, it seems
reasonable to assume that the impact can be categorized into five
reasonably well defined headings:
 The nano-enhanced fossil fuel sector
 Fuel cells and the nanoengineered hydrogen economy
 Nanosolar power
 The nano-enhanced electricity grid of the future
 Nanopower for the pervasive communications network

Nanosolar Power
Like fuel cells, solar power has
been on the verge of solving our
energy problems for a long time,
but somehow has never managed
to actually do so. This is because
solar power fact that it based on
inexpensive, but low energy density
fuels, so by the time it is delivered
to the customer they are quite
expensive. The promise of
nanotechnology in this cases is that
it will make solar power much
cheaper to do useful work.

Nanosolar Power
There are actually (at least) Two possible ways in which people have
proposed harnessing the power of the sun:
Passive solar
 Passive solar heating involves two main elements: south facing glass and a
thermal mass to absorb, store, and distribute heat.
 It seems possible that nanotechnology could make a contribution here with
better materials to improve both aspects of a passive solar power heating
system.
 Passive solar has proved quite effective, although it is not a system that can
be easily retrofitted, because much of its effectiveness lies in the basic
design of the home or other building.

Nanosolar Power
Photovoltaic (PV) systems
 Systems that come in various shapes and sizes that create
electricity through the photovoltaic effect, which is a physical
phenomenon in which electrons are freed from materials by
bombarding them with photons. In this case the photons are
coming from the sun.
 Photovoltaic systems have been around for quite some time
and have found a number of niche applications, although they
never seem to have lived up to the lofty expectations of some
of their backers. Several companies are researching how
nanoengineeredmaterials can reduce the cost of photovoltaic
systems.

Photovoltaic (PV) System
As we have already know, the fuel for PV is
free, but the capital costs of the PV system are
high and the efficiencies are low, so to obtain
large quantities of power a considerable
amount of real estate is taken up with solar
panels. As a result of these undeniable facts
about solar, the prospects for solar energy have
often been dismissed by analysts, who also
note that the improvements in cost and
efficiency of PV have not changed much in 30
years. Nanotechnology, however, may be able
to waken PV from its slumber.

Photovoltaic (PV) System Mechanism of Generation
The solar cell is composed of a P-type semiconductor and an N-type semiconductor.
Solar light hitting the cell produces two types of electrons, negatively and positively
charged electrons in the semiconductors. Negatively charged (-) electrons gather
around the N-type semiconductor while positively charged (+) electrons gather
around the P-type semiconductor. When you connect loads such as a light bulb,
electric current flows between the two electrodes.

Photovoltaic (PV) System Mechanism of Generation
Voltage and Current of PV
cell ( I-V Curve )

Photovoltaic (PV) System Various Type of PV
Types and Convension
Efficiensy of Solar Cell

 Crystal cell (Single
crystal
 Poly crystalline
Silicon)

Surface of PV cell

Use insolation efficiently
and reduce materials

Buried Contact Solar Cell

Photovoltaic (PV) System Fabrication Methode
How to make PV’s Silicon

Single Crystal Silicon
Production Process

Poly Crystalline Silicon
Production Process

From Ingot to Module

From Ingot to Module (Continue)

Belt Furnace

Photovoltaic (PV) System Installation
Solar Home System (SHS) as Example

Photovoltaic (PV) System The Characteristics
Adventages
 Clean
Solar energy is a clean energy. It emits
very small
amount of carbon gases or sulfur
oxides.
 Infinite
Solar energy is infinite and
permanent.
Disadventages
 Volatile in output
The amount of sunlight varies according to
seasons and weather. Therefore, generating
electric power to meet the demand anytime is
impossible.
 Low in power density
Regardless of the vast solar energy coming down
to the earth, power density in sunlight can be as
low as 1,000 watts/m2. Acquisition of vast
amount of energy needs vast surface area of the
solar cell.

Photovoltaic (PV) System Future Development
Advance Photon Management
Advances and improvements in efficiency involve materials that are applied externally to the cell, allowing
them to be developed independently without impacting cell designs that are highly optimized. This
decoupling is important because strategies and materials can be used in different technologies. Specific
topics within this area, in order of increasing complexity are as follows.
 Antireflection Coatings
Multi-layer or nanostructured antireflection coatings can extend photon collection both across the
spectrum and at diffuse angles beyond normal incidence.
 Increasing the Path Length through the Absorber.
Texturing, microstructures, or nanostructure-based on plasmonics divert photons coming normal to
the surface to more oblique angles, increasing the path lengths of these photons through the absorber
and, thus, the probability of absorption.
 Optical field enhancement
Plasmonic enhancement of the optical field in the vicinity of a metal nanoparticle is used to increase
optical absorption and hence carrier generation.

 Downshifting
This is the process of converting high-energy UV and blue photons, and downconverting their
energy to the middle of the visible spectrum where quantum efficiency values typically
approach 100%.
 Downconversion
Often called photon splitting, this is the process of transforming one high energy photon into
two photons that still have sufficient energy to create electron-hole pairs.
 Upconversion
This is the reverse process whereby two low energy photons are combined to produce one high
energy photon that is capable of generating an electron-hole pair
These last two processes are a very long way from being practical, but provide perhaps the best
opportunity to truly surpass the S-Q limit by altering the solar spectrum to produce a photon
distribution that is more aligned with the requirements of a single junction device.

Can Glass be Replaced?
This is a simple but critical question. A detailed analysis of thin film
manufacturing suggested that under optimal conditions manufacturing costs
could be reduced. It is not realistic to expect costs to be any lower for any
technology that requires the use of glass and a transparent conducting oxide.
A low cost, light-weight alternative that provides the same level of
transparency, protection, and thermal stability would be nothing short of
revolutionary. A positive answer to this question is essential if technologies
such as OPV and DSC are to become cost-competitive for principal power
generation.

Tugas nanotechnology

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