| Aerographene (14) |  |
| Aggregated diamond nanorod (27) | |
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| Carbon nanobud (6) | |
| Carbon nanomaterial (20) | |
| Fullerene (68) | |
| Graphene (2548) | |
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| Nanochannel glass material (17) | |
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| Nanoporous material (7) | |
that technology uses electrically conducting inks made from a pure-carbon material called graphene, which is basically the same stuff as the walls of carbon nanotubes
This technique, made possible through the use of graphene, results in extremely fast response times of tenths of a second,
These nanoelectronic graphene vapor sensors can be embedded completely in a microgas chromatography system which is the gold standard for vapor analysis,
Molybdenum disulfide isn t quite as flat as graphene the atom-thick form of pure carbon
When viewed from above it looks like graphene with rows of ordered hexagons. But seen from the side three distinct layers are revealed with sulfur atoms in their own planes above and below the molybdenum.
#Hybrid#dots#offer cheaper way to run fuel cells Last year chemist James Tour made graphene quantum dots from coal.
Now his team has combined the dots with tiny sheets of graphene. The result is a hybrid material that could make it much cheaper to generate energy with fuel cells.
The lab discovered boiling down a solution of graphene quantum dots (GQDS) and graphene oxide sheets (exfoliated from common graphite) yielded self-assembling nanoscale platelets that could then be treated with nitrogen and boron.
and excellent conductivity between GQDS provided by the graphene base. The boron and nitrogen collectively add more catalytically active sites to the material than either element would add alone. he GQDS add to the system an enormous amount of edge
which permits the chemistry of oxygen reduction one of the two needed reactions for operation in a fuel celltour says. he graphene provides the conductive matrix required.
and extraordinarily useful. he team s discovery comes after nearly a century of failed attempts by other labs to compress separate carbon-containing molecules like liquid benzene into an ordered diamondlike nanomaterial. e used the large
necessary to make these diamond nanothreads under more practical conditions. he nanothread also may be the first member of a new class of diamond-like nanomaterials based on a strong tetrahedral core. ur discovery that we can use the natural
and therefore less-polluting vehicles. ne of our wildest dreams for the nanomaterials we are developing is that they could be used to make the super-strong lightweight cables that would make possible the construction of a pace elevatorwhich so far has existed only as a science-fiction ideabadding says.
#Canâ graphene transform an apple into a doughnut? ETH Zurich rightoriginal Studyposted by Barbara Vonarburg-ETH Zurich on September 25 2014 More than 50 years ago a Russian physicist predicted that it s possible to transform from one topography to another.
and now researchers have used a double layer of graphene to demonstrate that it is indeed possible. e were able to prove the existence of a Lifshitz transitionsays Anastasia Varlet a doctoral candidate at ETH Zurich who was part of the research team that made the discovery.
nevertheless the researchers have achieved exactly that by using a double layer of graphene. The Lifshitz transition does not apply to objects in our normal environment;
when experimenting with the double layer of graphene: at a low water level there are three independent but equivalent lakes.
and initially the ETH team was had unaware it found the material that others had been looking for. e observed something strange in our measurements with the graphene sandwich construction that we were not able to explainsays Varlet.
To produce the sandwich construction Varlet enclosed the double layer of graphene in two layers of boron nitride a material otherwise used for lubrication
when added to a standard polymer-fullerene mixture. ullerene a small carbon molecule is one of the standard materials used in polymer solar cellslu says. asically in polymer solar cells we have a polymer as electron donor
and fullerene as electron acceptor to allow charge separation. n their work the researchers added another polymer into the device resulting in solar cells with two polymers and one fullerene.
when an optimal amount of PID2 was added the highest ever for solar cells made up of two types of polymers with fullerene
In order for a current to be generated by the solar cell electrons must be transferred from polymer to fullerene within the device.
But the difference between electron energy levels for the standard polymer-fullerene is large enough that electron transfer between them is difficult.
The detector which is interconnected based on the carbon atoms in graphene can sense light over an unusually broad range of wavelengths including terahertz waves between infrared
#Test keeps graphene pure enough for electronics Rice university rightoriginal Studyposted by Mike Williams-Rice on August 18 2014it s easy to accidentally introduce impurities to graphene
They expect the finding to be important to manufacturers considering the use of graphene in electronic devices.
Even a single molecule of a foreign substance can contaminate graphene enough to affect its electrical and optical properties says Junichiro Kono of Rice university.
The researchers used it as a substrate for graphene. Hitting the combined material with femtosecond pulses from a near-infrared laser prompted the indium phosphide to emit terahertz back through the graphene.
Imperfections as small as a stray oxygen molecule on the graphene were picked up by a spectrometer. he change in the terahertz signal due to adsorption of molecules is remarkablekono says. ot just the intensity
but also the waveform of emitted terahertz radiation totally and dynamically changes in response to molecular adsorption and desorption.
and changes over time. he laser gradually removes oxygen molecules from the graphene changing its density
The experiment involved growing pristine graphene via chemical vapor deposition and transferring it to an indium phosphide substrate.
Laser pulses generated coherent bursts of terahertz radiation through a built-in surface electric field of the indium phosphide substrate that changed due to charge transfer between the graphene and the contaminating molecules.
or any future device designs using graphene we have to take into account the influence of the surroundingssays Kono.
Graphene in a vacuum or sandwiched between noncontaminating layers would probably be stable but exposure to air would contaminate it he says.
and Masayoshi Tonouchi at Osaka s Institute of Laser Engineering are continuing to collaborate on a project to measure the terahertz conductivity of graphene on various substrates says Kono.
This technique made possible through the use of graphene results in extremely fast response times of tenths of a second as opposed to the tens or hundreds of seconds typical in existing technology.
These nanoelectronic graphene vapor sensors can be embedded completely in a microgas chromatography system which is the gold standard for vapor analysis the researchers say.
#Stretchy, bendy, stronger-than-ever graphene fiber Researchers have created a simple and scalable method of making strong,
stretchable graphene oxide fibers that are scrolled easily into yarns and have strengths approaching that of Kevlar. This method opens up multiple possibilities for useful products.
For instance, removing oxygen from the graphene oxide fiber results in a fiber with high electrical conductivity. Adding silver nanorods to the graphene film would increase the conductivity to the same as copper,
which could make it a much lighter weight replacement for copper transmission lines. In addition, the researchers believe that the material lends itself to many kinds of highly sensitive sensors. e found this graphene oxide fiber was very strong
much better than other carbon fibers, says Mauricio Terrones, professor of physics, chemistry and materials science and engineering,
GRAPHENE SLURRY FILM The researchers made a thin film of graphene oxide by chemically exfoliating graphite into graphene flakes,
He and graduate student Andrew Westover have built small aferdevices in the Nanomaterials and Energy Devices Laboratory there. ndrew has managed to make our dream of structural energy storage materials into a realitysays Pint.
and then coated with a protective ultrathin graphene-like layer of carbon. Sandwiched between the two electrodes is a polymer film that acts as a reservoir of charged ions similar to the role of the electrolyte paste in a battery.
and solidifies it forms an extremely strong mechanical bond. he biggest problem with designing load-bearing supercaps is preventing them from delaminatingsays Westover. ombining nanoporous material with the polymer electrolyte bonds the layers together tighter than superglue. he use
and bacteria that create a protective web of cellulose. ith this in mind cellulose nanomaterials are inherently renewable sustainable biodegradable and carbon-neutral like the sources from
#Car paint with graphene gets ice off radar domes Rice university rightoriginal Studyposted by Mike Williams-Rice on December 18 2013ribbons of ultrathin graphene combined with polyurethane paint meant for cars can keep ice off of sensitive military
because they re very poor conductors. nter graphene the single-atom-thick sheet of carbon that both conducts electricity and because it s so thin allows radio frequencies to pass unhindered.
Spray-on deicing material that incorporates graphene nanoribbons would be lighter cheaper and more effective than current methods Tour says.
when (Lockheed martin engineer) Vladimir Volman saw a presentation by Yu Zhu a postdoc in my lab at the timehe says. olman had calculated that one could pass a current through a graphene film less than 100 nanometers thick
and Volman recognized the potential. ristine graphene transmits electricity ballistically and would not produce enough heat to melt ice
but graphene nanoribbons (GNRS) unzipped from multiwalled carbon nanotubes in a chemical process invented by the Tour group in 2009 do the job nicely he says.
#From coal, cheap quantum dots in one step Chemists have discovered how to reduce three kinds of coal into graphene quantum dots (GQDS) that could be used for medical imaging as well as sensing electronic and photovoltaic applications.
In quantum dots microscopic discs of atom-thick graphene oxide band gaps are responsible for their fluorescence and can be tuned by changing the dots'##size.
That involved crushing the coal and bathing it in acid solutions to break the bonds that hold the tiny graphene domains together. ou can'##t just take a piece of graphene
and silicon for electronicssays nanoscientist Chad A. Mirkin. he precise placement of atoms within a well-defined lattice defines these high-quality crystals. ow we can do the same with nanomaterials
research group developed the ecipefor using nanomaterials as atoms DNA as bonds and a little heat to form tiny crystals.
engineers turned to atomically thin graphene. James Hone a mechanical engineering professor at Columbia University who co-led the project says the work emonstrates an application of graphene that cannot be achieved using conventional materials.
And it s an important first step in advancing wireless signal processing and designing ultrathin efficient cell phones. ur devices are much smaller than any other sources of radio signals
The combination of these properties makes graphene an ideal material for nanoelectromechanical systems (NEMS) which are scaled-down versions of the microelectromechanical systems (MEMS) used widely for sensing of vibration and acceleration.
In this new study published in Nature Nanotechnology the team took advantage of graphene s mechanical tretchabilityto tune the output frequency of their custom oscillator creating a nanomechanical version of an electronic component known as a voltage controlled oscillator (VCO.
The team built a graphene NEMS whose frequency was about 100 megahertz which lies right in the middle of the FM radio band (87.7 to 108 MHZ).
They used low-frequency musical signals (both pure tones and songs from an iphone) to modulate the 100 MHZ carrier signal from the graphene
While graphene NEMS will not be used to replace conventional radio transmitters they have many applications in wireless signal processing. ue to the continuous shrinking of electrical circuits known as Moore s Law today s cell phones have more computing
and their frequency can be tuned over a wide range because of graphene s tremendous mechanical strength. here is a long way to go toward actual applications in this areanotes Hone ut this work is an important first step.
and Shepard groups are now working on improving the performance of the graphene oscillators to have lower noise.
At the same time they are also trying to demonstrate integration of graphene NEMS with silicon integrated circuits making the oscillator design even more compact.
and stabilize the sulfur the researchers used amylopectin a polysaccharide that s a main component of corn starch. he corn starch can effectively wrap the graphene oxide-sulfide composite through the hydrogen bonding to confine the polysulfide among the carbon layerssays Hao Chen
what would happensays Pint. ypically researchers grow graphene from silicon-carbide materials at temperatures in excess of 1400 degrees Celsius.
But at lower temperatures 600 to 700 degrees Celsius we certainly didn t expect graphene-like material growth. hen the researchers pulled the porous silicon out of the furnace they found that it had turned from orange to purple or black.
but it was coated by a layer of graphene a few nanometers thick. They tested the coated material
And when they used it to make supercapacitors they found that the graphene coating improved energy densities by over two orders of magnitude compared to those made from uncoated porous silicon and significantly better than commercial supercapacitors.
The graphene layer acts as an atomically thin protective coating. Pint and his group argue that this approach isn t limited to graphene. he ability to engineer surfaces with atomically thin layers of materials combined with the control achieved in designing porous materials opens opportunities for a number of different applications beyond energy storagehe
says. espite the excellent device performance we achieved our goal wasn t to create devices with record performancesays Pint. t was to develop a road map for integrated energy storage.
By adding modified single-atom-thick graphene nanoribbons (GNRS) to thermoplastic polyurethane (TPU) the team at Rice made it 1000 times harder for gas molecules to escape Tour says.
The researchers acknowledge that a solid two-dimensional sheet of graphene might be the perfect barrier to gas
but the production of graphene in such bulk quantities is not yet practical Tour says. But graphene nanoribbons are already there.
Tour s breakthrough nzippingtechnique for turning multiwalled carbon nanotubes into GNRS first revealed in Nature in 2009 has been licensed for industrial production. hese are being produced in bulk
But the overlapping 200-to 300-nanometer-wide ribbons dispersed so well that they were nearly as effective as large-sheet graphene in containing gas molecules.
The GNRS geometry makes them far better than graphene sheets for processing into composites Tour says.
The Air force Research Laboratory through the University Technology Corp. the Office of Naval Research MURI graphene program and the Air force Office of Scientific research MURI program supported the research.
#At super high temps, white graphene stops rust Atomically thin sheets of hexagonal boron nitride (h-BN) have the handy benefit of protecting
They also grew h-BN on graphene and found they could transfer sheets of h-BN to copper
and other types of nanomaterials. he most interesting aspect of this work is the ability to combine top down techniques of jet printing with â##bottom upâ##processes of self-assembly in a way that opens up new capabilities
in lithographyâ##applicable to soft and hard materials alikerogers says. he opportunities are in forming patterned structures of nanomaterials to enable their integration into real devices.
Scientists at Cornell and Germany s University of Ulm had been making graphene a two-dimensional sheet of carbon atoms in a chicken wire crystal formation on copper foils in a quartz furnace.
They noticed some uckon the graphene and upon further inspection found it to be composed of the elements of everyday glass silicon and oxygen.
This produced the glass layer on the would-be pure graphene. The work that describes direct imaging of this thin glass was published first in January 2012 in Nano Letters
the researchers sandwiched it between layers of reduced graphene oxide and two current collectors to form a supercapacitor.
#Compact graphene device could shrink supercapacitors Monash University rightoriginal Studyposted by Emily Walker-Monash on August 5 2013monash U. AUS)# A new strategy to engineer graphene-based supercapacitors could make them viable
Graphene which is formed when graphite is broken down into layers one atom thick is very strong chemically stable and an excellent conductor of electricity.
To make their uniquely compact electrode Li s team exploited an adaptive graphene gel film they had developed previously.
They used liquid electrolytes#generally the conductor in traditional supercapacitors#to control the spacing between graphene sheets on the subnanometer scale.
maintaining the minute space between the graphene sheets and conducting electricity. Unlike in traditional#hard#porous carbon where space is wasted with unnecessarily large pores density is maximized without compromising porosity in Li s electrode.
#We have created a macroscopic graphene material that is a step beyond what has been achieved previously. It is almost at the stage of moving from the lab to commercial development#Li says.
##Solar steam kills germs while off the grid RICE (US) A new sterilization system uses nanomaterials to convert 80 percent of the energy in sunlight into heat,
#Graphene#s jagged edge can easily slice cells Brown University right Original Study Posted by Kevin Stacey-Brown on July 10 2013brown (US) the jagged edges of tiny graphene sheets
After the membrane is pierced an entire graphene sheet can be pulled inside the cell where it may disrupt normal function.
The new insight may be helpful in finding ways to minimize the potential toxicity of graphene says Agnes Kane chair of the pathology and laboratory medicine department at Brown and one of the study s authors.
Discovered about a decade ago graphene is a sheet of carbon just one atom thick.
and material scientists at Brown aimed at understanding the toxic potential of a wide variety of nanomaterials.
Their work on graphene started with some seemingly contradictory findings. Oddly shaped flakes Preliminary research by Kane s biology group had shown that graphene sheets can indeed enter cells
but it wasn clear how they got there. Huajian Gao professor of engineering tried to explain those results using powerful computer simulations
His models which simulate interactions between graphene and cell membranes at the molecular level suggested that it would be quite rare for a microsheet to pierce a cell.
The problem turned out to be that those initial simulations assumed a perfectly square piece of graphene.
In reality graphene sheets are rarely so pristine. When graphene is exfoliated or peeled away from thicker chunks of graphite the sheets come off in oddly shaped flakes with jagged protrusions called asperities.
When Gao reran his simulations with asperities included the sheets were able to pierce the membrane much more easily.
She placed human lung skin and immune cells in Petri dishes along with graphene microsheets. Electron microscope images confirmed that graphene entered the cells starting at rough edges and corners.
The experiments showed that even fairly large graphene sheets of up to 10 micrometers could be internalized completely by a cell.
The engineers and the material scientists can analyze and describe these materials in great detail Kane says.
what happens once a graphene sheet gets inside the cell. But Kane says this initial study provides an important start in understanding the potential for graphene toxicity.
This is about the safe design of nanomaterials she says. Theye man-made materials so we should be able to be clever
and make them safer. Other contributors to the study were Brown graduate students Yinfeng Li (now a professor at Shanghai Jiao Tong University) Hongyan Yuan and Megan Creighton.
#Graphene ribbons improve lithium ion batteries Anodes for lithium ion batteries built with ribbons of graphene perform better, tests show.
Rice university chemist James Tour and colleagues, who developed a method for unzipping nanotubes into graphene nanoribbons (GNRS),
figured out how to make graphene nanoribbons in bulk and are moving toward commercial applications. One area ripe for improvement is the humble battery.
In the new experiments, the Rice lab mixed graphene nanoribbons and tin oxide particles about 10 nanometers wide in a slurry with a cellulose gum binder and a bit of water, spread it on a current collector
##Quilted graphene is also super strong COLUMBIA U. US) Graphene, even if stitched together from many small crystalline grains,
Graphene consists of a single atomic layer of carbon, arranged in a honeycomb lattice. ur first Science paper,
in 2008, studied the strength graphene can achieve if it has no defectsts intrinsic strength,
pristine graphene exists only in very small areas. Large-area sheets required for applications must contain many small grains connected at grain boundaries,
reports on the strength of large-area graphene films grown using chemical vapor deposition (CVD), and wee excited to say that graphene is back and stronger than ever.
The study verifies that commonly used methods for postprocessing CVD-grown graphene weaken grain boundaries
resulting in the extremely low strength seen in previous studies. The team developed a new process that prevents any damage of graphene during transfer. e substituted a different etchant
and were able to create test samples without harming the graphene, notes the paper lead author, Gwan-Hyoung Lee,
a postdoctoral fellow in the Hone lab. ur findings clearly correct the mistaken consensus that grain boundaries of graphene are weak.
This is great news because graphene offers such a plethora of opportunities both for fundamental scientific research and industrial applications.
In its perfect crystalline form, graphene (a one-atom-thick carbon layer) is the strongest material ever measured
as the team reported in 2008o strong that, as Hone observes, t would take an elephant, balanced on a pencil,
to break through a sheet of graphene the thickness of Saran wrap. For the first study, the team obtained small, structurally perfect flakes of graphene by mechanical exfoliation,
or mechanical peeling, from a crystal of graphite. But exfoliation is a time-consuming process that will never be practical for any of the many potential applications of graphene that require industrial mass production. httpv://www. youtube. com/watch?
v=VSPWRC6RCVY Why so weak? Currently, scientists can grow sheets of graphene as large as a television screen by using chemical vapor deposition (CVD), in
which single layers of graphene are grown on copper substrates in a high-temperature furnace. One of the first applications of graphene may be as a conducting layer in flexible displays. ut CVD graphene is titchedtogether from many small crystalline grainsike a quiltt grain boundaries that contain defects
in the atomic structure, Kysar explains. hese grain boundaries can severely limit the strength of large-area graphene
if they break much more easily than the perfect crystal lattice, and so there has been intense interest in understanding how strong they can be.
The team wanted to discover what was making CVD graphene so weak. In studying the processing techniques used to create their samples for testing,
they found that the chemical most commonly used to remove the copper substrate also causes damage to the graphene,
severely degrading its strength. Their experiments demonstrated that CVD graphene with large grains is exactly as strong as exfoliated graphene,
showing that its crystal lattice is just as perfect. And, more surprisingly, their experiments also showed that CVD graphene with small grains
even when tested right at a grain boundary, is about 90 percent as strong as the ideal crystal. his is an exciting result for the future of graphene,
because it provides experimental evidence that the exceptional strength it possesses at the atomic scale can persist all the way up to samples inches
Strong, large-area graphene can be used for a wide variety of applications such as flexible electronics and strengthening componentsotentially,
a science fiction idea of a space elevator that could connect an orbiting satellite to Earth by a long cord that might consist of sheets of CVD graphene,
since graphene (and its cousin material, carbon nanotubes) is the only material with the high strength-to-weight ratio required for this kind of hypothetical application.
The team is excited also about studying 2d materials like graphene. ery little is known about the effects of grain boundaries in 2d materials
This is due to all the atoms in graphene being surface atoms, so surface damage that would normally not degrade the strength of 3d materials can completely destroy the strength of 2d materials. owever with appropriate processing that avoids surface damage,
especially graphene, can be nearly as strong as the perfect, defect-free structure. The Air force Office of Scientific research and the National Science Foundation supported the research c
but within 40 years neurons made from nanomaterials could enable humans to survive even the most horrendous accident,
predicts in his#blogthat expected advances in molecular nanotechnology will one day enable us to replace brain cells with damage-resistant nanomaterials that process thoughts faster than today s biological brains.##
A daily pill would supply nanomaterials and instructions for nanobots to form new neurons and position them next to existing brain cells to be replaced.
##The scientists believe that using super-thin#graphene sheets could make the process even more efficient, making synthetic gas less of a concept and more of a reality.
substituting a super capacitor made from advanced carbon fiber-based nanomaterials that can be integrated into the body panels of the vehicle.
and roof panels are made of nanomaterial (see image below) that replaces the electric batteries used by conventional EVS.
A new nanomaterial recently invented does the seemingly impossible: It hides things from touch. Just a thin layer of this amazing polymer will hide anything under it from being perceived by your sense of touch.
#Researchers discover 3d material that behaves like graphene This illustration depicts fast-moving, massless electrons inside cadmium arsenide.
and Berkeley Lab have found that cadmium arsenide could yield practical devices with the same extraordinary electronic properties as 2d graphene.
There is a quest to find graphene-like materials that are three-dimensional and thus much easier to craft into practical devices.
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