Editorial: Nanotechnology: The Rubber (Finally) Meets the Road

By Paul Nesdore
January/February 2008

Starting from less than front-page applications like non-absorbent
clothing (spill red wine on your necktie and it runs right off ),
water-free auto windshields (no need for wipers), and airbag sensors,
nanotechnology is beginning to fulfill its promises in many areas; and
the world of gases is no exception.

An excellent example of the nano-gas connection is the work being done
by Applied Nanotech (ANI)*, a company I have been talking with for a
number of years about their cutting-edge research and products. My
initial conversation, over a year ago, with Dr. Zvi Yaniv, President
and COO of ANI, was concerning CO2 and O2 sensors used inside of
shipping containers to detect whether a human was concealed. Recently,
ANI released information on their ongoing foray into the nanoworld
[See News, this issue, page 6] where a further development is taking
place with their PhotoScrub(R) product, a thin film coating on a
flexible fiberglass cloth that decomposes organic pollutants at the
molecular level in gases and liquids.

The principle of PhotoScrub is based on the catalytic effect of UV
light on titanium oxide, TiO2. While this phenomenon was known
earlier, by introducing nanophase material as ANI did and creating
crystalline columns of TiO2 , the surface area is significantly
increased making the catalytic effect much stronger. Because of this,
Dr. Yaniv explains, "We will be able to destroy larger organisms."

The principle is that when UV light impinges on the surface, a
disassociation occurs with organic molecules consisting of carbon,
hydrogen, and oxygen, resulting in water and carbon dioxide. "Also, it
should be noted, that if you can monitor the water and the amount of
CO2 created, it becomes a good sensor," explains Yaniv.

The application to homeland security is important. Among other
pathogens, this process can also destroy anthrax. PhotoScrub was
tested with actual anthrax (not a surrogate) with excellent results.
Tests showed a 99.4% reduction of anthrax spores in less than 20
minutes in a laboratory HVAC setup. Phase II of ANI's work on
PhotoScrub will involve the creation of a unit that can be installed
in air ducts of HVAC systems.

Another interesting project that ANI is involved in relates to the
ionization process based on electron emission from carbon nanotubes
(CNT). "Several years ago we were the first in the world to provide an
electron source based on CNT," relays Yaniv. The history of CNT and
ionization goes back about 10 years ago, when as Yaniv explains,
advancement was stymied because everyone believed you needed a very
high vacuum to produce the emissions. Now ANI has shown, that is not
necessary.

Sionex Corporation is partnering with ANI to replace a radioactive ion
source in a particular Sionex detection device using electron emission
from CNT. Chief Scientist at Sionex, Dr. Erkinjon Nazarov explains,
"The project is the result of applying sound fundamental scientific
principles to very sound high technology. The result is the stable
production of ions, both positive and negative, at atmospheric
pressure without the need for a radioactive source, conventional
plasma, or corona discharge technologies."The elimination of the
radioactive source is especially important to Homeland Security,
reducing the potential proliferation of radioactive materials that
could be used in "dirty bombs."

Future applications are many, perhaps most importantly, detectors.
"With the ionized particles, you can attract them, differentiate by
mass; you can differentiate by electrical charge--and suddenly you have
a beautiful nano-mechanism for sensing," quotes Yaniv.

So where is nanotechnology headed now? Yaniv looks at the development
of nano-science as "enormous." "It will be in facilitating products,
not pure 'nano-products.' Yaniv even expands this further. "Is there a
product that does not use natural science (physics, chemistry,
biology, mathematics) on the market?" Nanotechnology he explains, is
just natural science

Paul Nesdore

*ANI is a wholly owned subsidiary of Nano-Proprietary Inc. ANI
contact: Lauren Johnson at 512-339-5020 or
ljohn...@appliednanotech.net

http://www.gasesmag.com/articles.asp?pid=22

Carbon Nanotubes of DNA

File Format: Microsoft Powerpoint
A DNA scaffold molecule provides the address for precise localization.
The realization of a SWNT FET in a test tube promotes self-assembly.

http://www.eng.buffalo.edu/Courses/ee240/studentprojects/spr2007/grou...

Biophysicist / Biochemist

Applied Nanotech, Inc., (Austin TX) is looking for a Biophysicist /
Biochemist to help start a project in DNA electronics, sensors or
similar applications. This could include using DNA scaffolding for
self-assembly of devices or systems. Will require building a team,
which may include collaborative efforts with university or other
organizations or companies. Require writing proposals to help acquire
funding support.

Education: PhD or equivalent required. Candidate should demonstrate
good verbal and written command of the English language. US citizen or
Green Card desired. Please send resumes to
Jsopt...@appliednanotech.net

http://www.nano-proprietary.com/ANI/EmploymentANI.asp

The next frontier for information processing may lie at the interface
of nanoelectronics and biotechnology.

DNA scaffolding
Special report: Minnesota's Digital Dynasty

An interdisciplinary team led by electrical and computer engineering
professor Richard Kiehl is exploring the use of DNA as a programmable
scaffolding for the self-assembly of nanoscale electronic components.
As a model for fabricating and designing semiconductor devices and
circuits, DNA offers two key advantages: size scale and
programmability.

Most industry experts believe that within the next 10 to 15 years the
ability to scale down conventional technologies will reach its limit.
At that point, the operating principles of conventional devices--and
the techniques used to fabricate them--will break down. The basic
elements of the DNA molecule are at just the right scale, says Kiehl.

Self-assembly uses bio-recognition, a natural process in which one
molecule is attracted to and binds with another to form small
structures. In the case of DNA, the attraction can be programmed so
that the molecules will spontaneously assemble in solution to achieve
a desired result.

"It's possible to synthesize small versions of DNA molecules in the
laboratory and program in whatever code you want," says Kiehl. "And
because the two strands of DNA have complementary codes that match up,
you can design one strand of DNA in a certain way so it will match
another strand and assemble a nanoscale structure this way."

The matched segments form a scaffolding on which nanoparticles are
affixed at highly selective attachment points. It's an approach that
offers the programmability and precision needed for assembling
electronic circuitry on the nanoscale.

"We have to make a real paradigm shift," Kiehl says. "Not only do we
have to keep improving performance, but we also must look at the kinds
of devices we can make at those scales and how we want to use them to
process information."

To that end, the researchers are turning to the human brain for
inspiration. They envision devices whose electrical characteristics
resemble those of neuron-like electrical waveforms in the brain. Like
certain regions of the brain, the devices would process information
based on pattern recognition rather than on individual bits of
information. It's a more sophisticated level of information processing
than can be achieved using conventional computers.

Kiehl predicts there will be a wide range of applications for this
technology, including signal processing, communications systems, and
computer systems. "The higher end of this [work] will be things that
computers can't do very well today because the operations they use are
too restrictive. One is the ability to recognize a pattern, such as
identifying a letter as being an 'A' or a 'B', or being able to
identify a face.

"It won't be just making things faster and faster in the conventional
way," he says. "It will really be opening up new ways to process
information in machines."

http://www.it.umn.edu/news/inventing/2000_Fall/nano_dnascaffold.html

3/26/2007 7:10:17 AM
US Department of Defense grant gives $6M to team of 9 scholars for the
study of quantum electronic arrays

The U.S. Department of Defense (DoD) has awarded a team of nine
scholars from six universities a grant of $6 million over five years
to exploit precise biological assembly techniques for the study of
quantum physics in nanoparticle arrays. This research will produce a
fundamental understanding of quantum electronic systems that could
impact future electronics.

Leading the effort is electrical and computer engineering professor
Richard Kiehl of the University of Minnesota, who has wide experience
in investigating the potential of novel fabrication techniques,
physical structures and architectures for electronics. Kiehl has
brought together a multidisciplinary team to develop biological
strategies combining DNA, proteins and peptides with chemical
synthesis techniques to construct arrays of nanoparticles and to
systematically characterize the resulting quantum electronic systems.

Interactions between precisely arranged nanoparticles could lead to
exotic quantum physics, as well as to new mechanisms for computing,
signal processing and sensing. But even basic studies of such
nanoparticle arrays have been hampered by the need to fabricate test
structures with extreme control and precision. "By exploiting biology
to precisely control size, spacing and composition in the arrays, we
will be able to examine electronic, magnetic and optical interactions
at much smaller scales than before," said Kiehl. "Our project blends
some really fascinating science at the edges of biology, chemistry,
materials science and physics. And, I'm excited about the chance to
impact how electronic circuits could be engineered in the future."

The team members are UCLA professors Yu Huang (materials science),
Kang Wang (electrical engineering) and Todd Yeates (biochemistry); New
York University professors Andrew Kent (physics) and Nadrian Seeman
(chemistry); University of Texas at Austin professor Allan MacDonald
(physics); University of Pennsylvania professor Christopher Murray
(chemistry & materials science); and Columbia University professor
Colin Nuckolls (chemistry).

Kiehl and Seeman have previously collaborated in the first
demonstrations of metallic nanoparticle self-assembly by DNA
scaffolding, which will be central to this project. Seeman will
exploit DNA nanotechnology to construct 2-D and 3-D scaffolding, while
Huang and Yeates will use peptides and proteins to make nanoparticle
clusters for assembly onto the scaffolding. Murray and Nuckolls will
synthesize metallic and magnetic nanoparticles with organic shells
that will self-assemble onto the scaffolding and control the
interparticle coupling. Kent, Kiehl and Wang will carry out
experiments to characterize the electronic, magnetic and optical
properties of the arrays. MacDonald will provide theoretical guidance
for the studies and analysis of the experimental results.

The award was made by the Army Research Office (Marc Ulrich, research
topic chief) and is one of 36 recently made under the highly
competitive DoD Multidisciplinary University Research Initiative
(MURI).

http://nanotechwire.com/news.asp?nid=4466&ntid=&pg=51

I followed Seeman's stuff a bit here on Nanalyze Forums:
http://www.nanalyze.com/forums/topic.asp?TOPIC_ID=1156

NANS - his company was ~$1 then - it is now a shell and sits at $0.012
http://finance.yahoo.com/q?s=NANS.OB

Annual Report - NANS - 8-Jan-2008

ITEM 6. MANAGEMENT'S DISCUSSION AND ANALYSIS OR PLAN OF OPERATION

The following information should be read in conjunction with the
consolidated financial statements and notes thereto appearing
elsewhere in this Form 10-KSB. We have determined on December 1, 2007
to cease operations immediately and, at the request of our principal
creditor appointed a director designated by such creditor to our Board
of Directors. Immediately following such appointment, our existing
directors resigned effective immediately and terminated their
association with us. Accordingly, such creditor may be deemed to
control us at the date of the filing of this Report. As a result of
our cessation of operations and the termination of the License
Agreement, we became a "blank check" or "shell company" whose sole
purpose at this time is to locate and consummate a merger or
acquisition with a private entity.
------

Certainly not greatly encouraging! Looks like the future is in the
hands of the DOD grants and perhaps ANI - who knows!! I'm looking
forward to my first DNA TV ;-)

Graphene Ribbons - Slim carbon strips show promise as semiconductors

Bethany Halford
January 28, 2008
 Volume 86, Number 04    p. 15

TYING TOGETHER materials science and chemistry, scientists have
developed a chemical method for making carbon ribbons less than 10 nm
wide and just one atom thick (Science, DOI: 10.1126/science.1150878).
The semiconducting properties of these so-called graphene nanoribbons
make them promising materials for electronics applications.

To create the graphene ribbons, Hongjie Dai and colleagues at Stanford
University first chemically exfoliate graphite, loosening individual
layers of graphene by giving the graphite a 60-second bath in 3%
hydrogen in argon gas at 1,000 °C. They then "tear" the graphene into
strips by sonicating the material in solution. Previously, scientists
used lithographic patterning to cut graphene into ribbons. But Dai's
chemical method yields narrower ribbons with far smoother edges.

Rodney S. Ruoff, a nanoengineering professor at the University of
Texas, Austin, says the work is exciting. "It is surprising that such
fine ribbons could result from processing through use of ultrasound,"
he notes, "so there is some underlying mechanics of a fairly selective
propagation of 'cracks' or 'tears'" in the exfoliated graphene.

Dai's effort represents a "significant leap" in graphene research,
according to Andre Geim, a physics professor at England's University
of Manchester. The new work, he says, shows "one needs to make ribbons
only a couple of times narrower than were previously reported to make
a qualitative change in characteristics and reach a good transistor
action required for integrated circuit applications."

To that end, Dai says the slim nanoribbons have useful properties at
room temperature that make them promising electronic components for
field-effect transistors and sensors. Furthermore, all the nanoribbons
that were less than 10 nm wide were semiconducting, unlike their
carbon nanotube cousins, which exist as a mix of semiconducting and
metallic materials.

Dai says that the electronic performance of nanoribbon-based devices
still needs further investigation. In the meantime, he says, the
nanoribbons "will provide an experimental test bed for studies of many
fundamental electrical, spectroscopic, and spin properties predicted
for these materials."

http://pubs.acs.org/cen/news/86/i04/8604notw7.html

Glorious Graphene - the next nano wonder material

January 18th, 2008

[SNIPS]
Graphene exhibits the highest electronic quality among all known
materials, a profound discovery that occurred less than 4 years ago.
Although theorists have known of graphene for over 60 years, the
community has been delighted to be able to confirm the materials
remarkable electronic properties. New insights continue to be
published on a monthly basis in leading scientific publications such
as Nature and Science. In doing so, advanced research groups both in
academia and industry are making graphene a major part of their
technology portfolio, migrating away from III-V semiconductors,
nanowires and carbon nanotubes. Structurally, graphene is similar to a
carbon nanotube, both made up of a single sheet of carbon atoms.
.......

To summarize, I am bullish on graphene. I foresee the following play:

1. Technology heavy weights such as IBM, HP, GE and DARPA will begin
(some already have) to establish serious efforts in targeting
synthesis of wafer scale graphene and development of high performance
devices (continue up to 2012).

2. Graphene IP applications will exponentially increase, comparable to
CNT numbers. Issued patents based on "graphene"=14 compared to
"CNT"=448 (continue up to 2016).

3. The VC community will take note and begin directing capital to
startups together with an increased SBIR call for graphene based
solutions (beginning between 2009-2011).

4. Large cap companies such as Samsung, Intel and Hitatchi and cash
rich startups will acquire or license enabling IP from academia and
startups that entered in the early stages (beginning between
2012-2015).

5. Highly capitalized development houses and foundries such as
SEMATECH, IMEC and LETI will be the first to integrate graphene on Si
(beginning between 2014-2017).

6. Small- and mid-cap corporations will begin commercialization of low
volume discrete graphene based devices such as sensors and RF
components (beginning 2015).

7. Semiconductor manufacturers will then adopted and transfer the
technology into their products (beginning 2019).

http://www.nanotech-now.com/columns/?article=160

Ref:
The Pavlovsky US patent 6,819,034:
http://tinyurl.com/yhdlhr
[SNIP]
Carbon flake is a carbon material with a graphitic structure. It can
be as thin as one or more layers of sp.sup.2 -bonded carbon atoms
(graphite layers), and can be very long in two other dimensions. The
length of a flake can be on the order of microns, whereas the
thickness is on the order of nanometer or tens of nanometers. Thus,
the aspect ratio for this material is very high. A flake, by its
nature, is a system of ordered or turbostratic graphite layers. Carbon
flakes fall into a class of nanostructured carbon materials. The
flakes can be grown by several methods that fall into the following
categories: 1. DC Glow Discharge. This method involves a direct
current glow discharge between two electrodes in a gas environment.
The plasma between the two electrodes is of the order of 1000.degree.
C. or higher. This method produces carbon flakes along with other
types of carbon materials such as carbon nanotubes. This method is
used for depositing directly onto a substrate. 2. Thermal CVD
(Chemical Vapor Deposition) Method. In this method, a carbon precursor
gas and a substrate are heated to a temperature of 600.degree. C. and
higher while thermal decomposition of the precursor is observed. The
substrate has a catalyst on the working surface, which gives rise to
growing carbon structures like carbon nanotubes and carbon flakes. A
bias voltage can be used to make carbon nanostructures grow straight.
This method is used for depositing directly onto a substrate.
******

IOW - the flakes ARE graphene! The word 'graphene' does not appear,
unfortunately - that article would then have noted '15' patents rather
than '14'! But have no doubts - GRAPHENE it is.

NPI=The Great Graphene Company

Solar/CNTs/Paintable/NPI?

Posted: January 18, 2008

STAR grantee develops potentially inexpensive nanotube solar
technology

(Nanowerk News) Somenath Mitra, along with researchers at the New
Jersey Institute of Technology (NJIT), has developed a potentially
cheap solar technology which can be painted or printed on flexible
plastic sheets. The benefits could be enormous to the consumer,
producer, and the environment. And while it may seem like something
out of science fiction, it's quickly becoming a reality. According to
Mitra it's actually a relatively simple process.

Dr. Mitra is a former STAR (EPA's 'Science to Achieve Results' grant
program) grantee who has an extensive background dealing in
nanotechnology. As a STAR researcher Mitra worked to develop sensing
systems that drew heavily on the nanoscale properties of carbon
nanotubes. This project led to better understanding of carbon nanotube
self-assembly and function. He has now worked to bring carbon
nanotubes into the world of solar technology. Solar technology, along
with most forms of renewable energy, requires expensive and energy-
intensive infrastructure. Mitra's technology, however, diverges from
standard photovoltaic cells which are silicon-based. Instead it
creates organic solar cells from polymers, a simpler and more
affordable alternative.

When sunlight hits these organic solar cells positive and negative
charges are created. The cell, as Mitra and his team at NJIT designed
it, is able to separate these charges to create a current. It contains
carbon nanotube complexes as well as another type of carbon molecule
called a fullerene. When the sunlight hits the polymer the fullerenes
are able to grab the excited electrons and the nanotubes conduct them,
thus creating a sustained current. The technology has endless
possibilities once you realize that the nanotubes can be turned into a
paint. "Once you develop a paint," Mitra says, "you can make a large
area into a solar panel very easily." This will be applicable to the
exterior wall of a building, a rooftop, or even a car. Mitra goes on,
"Imagine some day driving in your hybrid car with a solar panel
painted on the roof, which is producing electricity to drive the
engine." The cells are simple, inexpensive to make, and incredibly
energy-efficient. The technology is still in its developmental phases
and far from the market. But it is an extremely promising and hopeful
direction for renewable energy.
Source: EPA

http://www.nanowerk.com/news/newsid=4134.php

Why did we get slammed today Don?

News -  January 11, 2008
E-noses Could Make Diseases Something to Sniff at
Diagnosing illnesses could be as easy as breathing.

By Emily Anthes

THE NOSE KNOWS: Bill Hanson of the University of Pennsylvania uses an
electronic nose to analyze exhaled breath for possible disease.

Ancient medical practitioners plied their trade by trusting their
noses. They knew that diabetes could make a patient's breath smell
sweet and that a wound emitting a foul odor was infected. These early
doctors, lacking today's sophisticated technology, often relied on
their sense of smell to diagnose illness.

Technology is now turning this ancient art into a modern science.
Engineers are developing electronic versions of the human nose that
will allow doctors, ever in search of less-invasive techniques, to tap
into what the nose knows about the human body.

"The sense of smell has been used as a medical diagnostic tool for
thousands of years," says Bill Hanson, an anesthesiologist and
critical care specialist at the University of Pennsylvania in
Philadelphia, who has studied whether odor can be used to diagnose an
ailment. "Both diseases and bacteria that cause diseases have
individual and unique odors. You can walk into a patient's room and
know immediately in some cases that the patient has such and such
bacteria just because of the odor."

The "odor signatures" of disease arise through one of several
mechanisms. Bacteria, like all living organisms, give off unique
mixtures of gases; bacterial infections may be diagnosed by the
characteristic scents of these gases. Alternately, nonbacterial
disorders, such as diabetes, may prompt biochemical changes that alter
the smell of a patient's body. But many of these odors may be tough
for the humans to detect and identify.

"The difference between normal breath and diseased breath may be very
subtle," says David Walt, a chemist at Tufts University in Boston who
designs chemical sensors and devices.

Enter the electronic nose", an emerging technology that can
distinguish these subtle differences. There are a variety of
electronic e-nose models, all of which consist of an array of
olfactory sensors that are activated in unique patterns when exposed
to different aromas; software identifies each odor and its source by
analyzing the patterns. (The human" brain uses this same pattern-
recognition process to identify smells.)

Though the technology was originally designed for other tasks, such as
sniffing out chemical leaks or detecting food spoilage, research is
increasingly revealing its diagnostic potential. Physicians can
effectively identify potential lung cancer patients, for instance, by
"smelling" their breath.

"When you have an exhaled breath, there are all sorts of volatile
organic compounds that are produced," says Serpil Erzurum, a
pulmonologist at Cleveland Clinic and co-author of a 2005 study on the
use of electronic noses to help diagnose lung cancer. "Those compounds
are a result of metabolism and, when you have cancer, metabolism
changes and the volatile organic compounds are altered. The changes
are detectable by an electronic nose."

Hanson showed that the technology is useful for diagnosing chronic
sinusitis and pneumonia, and other researchers proved that the noses
can distinguish asthmatic patients from healthy ones.

And the noses don't just analyze breath. Some can also sniff out
infections in urine, blood and other bodily fluids. A team of British
scientists, for instance, used electronic noses to pinpoint antibiotic-
resistant bacteria in the nasal swabs of hospital patients.

Combine these feats with the fact that artificial noses are faster,
cheaper and less invasive than many other diagnostic tests, and it is
easy to understand why physicians find the technology appealing.
Erzurum says it could make a dramatic difference in the success of
treatments, paving the way for early detection of lung cancer and
other diseases.

"Some of the newer nose technologies are very portable," Hanson says.
"They're suitable to being taken to the bedside and being handheld.
You can imagine a patient breathing into one of these and getting a
fast, inexpensive answer to a question you might have."

Scientists who have tested the noses envision a time in the not-too-
distant future when a patient with, say, the sniffles can go to the
doctor, breathe into an electronic nose, and know in a matter of
minutes whether he or she has a sinus infection and needs antibiotics.

But Walt says there is still a long way to go before this scenario
becomes a reality. "I've yet to be convinced,'' he says, "that there's
[now] a working version of an artificial nose out there that can
consistently do this."

Though far from perfect, Hanson says, the current technology can be
used as a screening tool to flag patients who should undergo more
advanced testing.

A number of companies manufacture electronic noses that detect
explosives and other dangerous compounds, but the technology is not
yet widely used in medicine. The Food and Drug Administration (FDA)
has approved an electronic nose that can detect urinary tract
infections, but has yet to approve one for breath analysis or other
medical uses.

"It's a field that's simmering," Hanson says. "It's just waiting for
somebody with deep pockets to come up with the money and focused
effort to develop these noses commercially."

http://www.sciam.com/article.cfm?id=electronic-noses-could-make-disea...

I have high hopes for NPI's nanonose:

http://www.nano-proprietary.com/PDFs/EXPO.PAS_Handout1.pdf
"Breath health monitors"

NPI Patents/Filings:
http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=...
http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=...

Combo of two nanotech approaches may provide more efficient solar
cells

January 9th, 2008 - 2:32 pm

Washington, January 9 (ANI): Combination of two nanotechnology
procedures one involving thin films of metal oxide nanoparticles doped
with other elements, and the other employing quantum dots or nanosize
crystals that strongly absorb visible light may significantly enhance
solar cells efficiency in converting sunlight into electricity,
suggests an international team of researchers.

Both doping and quantum dot sensitisation extend the visible light
absorption of the metal oxide materials.

Lead researcher Jin Zhang, professor of chemistry at the University of
California, Santa Cruz, says that the combination of the two
approaches produces better solar cell materials than either one alone
does.

His team which includes researchers from California, Mexico, and China
created a thin film doped with nitrogen and sensitised with quantum
dots. The new nanocomposite materials functioning was greater than the
sum of its two individual components, they found.

"We have discovered a new strategy that could be very useful for
enhancing the photo response and conversion efficiency of solar cells
based on nanomaterials," Zhang said.

"We initially thought that the best we might do is get results as good
as the sum of the two, and maybe if we didn't make this right, we'd
get something worse. But surprisingly, these materials were much
better," he added.

Zhang believes that the nanocomposite material may provide not only
solar cells with enhanced efficiency, but also a state-of-the-art
photoelectrochemical cell that will use energy generated from sunlight
to split water and produce hydrogen fuel.

He also feels that their nanocomposite material may potentially be
useful in devices for converting carbon dioxide into hydrocarbon
fuels, such as methane.

"I'm very excited because this work is preliminary and there's a lot
of optimizing we can do now. We have three materials-or three
parameters-that we can play with to make the energy levels just
right," Zhang said.

He revealed that his team has been trying to manipulate materials so
that when sunlight strikes them, the free electrons generated could
easily move from one energy level to another, or jump across the
different materials, and be efficiently converted to electricity.

"What we're doing is essentially 'band-gap engineering.' We're
manipulating the energy levels of the nanocomposite material so the
electrons can work more efficiently for electricity generation. If our
model is correct, we're making a good case for this kind of strategy,"
Zhang said.

The research teams work has been reported in the Journal of Physical
Chemistry. (ANI)

http://www.thaindian.com/newsportal/health/combo-of-two-nanotech-appr...

Graphene makes movement easy for electrons

07 Jan 2008
Researchers at The University of Manchester have found that electrons
move more easily in graphene than all other materials, including gold,
silicon, gallium arsenide and carbon nanotubes.

The work has implications for the future development of ultra-high
frequency transistors and wiring in electronic circuits - and
academics say their findings have singled graphene out as the "best
possible" material for electronic applications.

With a high electronic quality - measured at around 200,000 cm2/Vs and
more than 100 times higher than for silicon - researchers believe
graphene has the potential to improve upon the capabilities of current
semiconductors and open up exciting new possibilities. These include
ultra-high frequency detectors required for full-body security
scanners, which would make people transparent by operating at
terahertz (THz) frequencies.

The research is reported in the latest issue of the American Physical
Society's journal Physical Review Letters, and has been carried out in
conjunction with The Institute for Microelectronics Technology in
Russia, The University of Nijmegen in the Netherlands and The
Department of Physics at Michigan Technological University in the
United States.

"The search is on for materials with higher electronic quality or
intrinsic mobility, which should improve the existing applications and
open up new ones," said Professor Andre Geim, one of the paper's
authors and director of The University of Manchester's Centre for
Mesoscience and Nanotechnology.

"Graphene exhibits the highest electronic quality among all known
materials - higher than copper, gold, silicon, gallium arsenide,
carbon nanotubes, and anything we know. It is the only material where
electrons at room temperature can move thousands of interatomic
distances without scattering.

"We knew that it could be a long distances and longer than for
silicon, but before our latest work we did not know, nor expected,
that graphene could beat carbon nanotubes or the record holder Indium
antimonide (InSb). Our work singles it out as the best possible
material for electronic applications.

"Our findings mean it is worth investing even more effort to develop
the material into viable products.

"Neither graphene nor carbon nanotubes can hope to compete with
silicon for about another 20 years. The advantage of graphene is that
it still holds a lot of promise, which must be investigated.

"The major problems for nanotubes do not exist for graphene. It does
have its own problems but they seem doable at least, unlike those for
nanotubes, which seemed impossible a few years ago and remain
impossible now.

"Whatever comes out as applications, the physics is extremely rich and
one can be sure that graphene is here to stay as long as silicon or
gallium arsenide, with many more interesting effects to be found.
Higher mobility will be a powerful facilitator."

Geim believes graphene-based devices like chemical gas sensors and THz
sources and detectors could begin to materialise within three to five
years.

Prof Geim added: "Our work puts fundamental limits on what can be
potentially done by using graphene. Previously, researchers speculated
that the sky was the limit for graphene's electronic quality. Now we
know this limit accurately enough. It is not endless but sky-high."
Notes for editors

Prof Andre Geim is available for interview.

A copy of the paper, 'Giant Intrinsic Carrier Mobilities in Graphene
and Its Bilayer' is available on request.

Please contact Alex Waddington, Media Relations Officer, The
University of Manchester, 0161 275 8387 or
alex.wadding...@manchester.ac.uk for more information.

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