#Self-Cleaning Woolen Fabrics Produced in Iran Woolen products are very good sources for the growth of bacteria and microorganisms due to their protein structure,
#More efficient process to produce graphene developed by Ben-Gurion University researchers Abstract: Ben-Gurion University of the Negev (BGU) and University of Western australia researchers have developed a new process to develop few-layer graphene for use in energy storage and other material applications that is faster,
potentially scalable and surmounts some of the current graphene production limitations. Graphene is a thin atomic layer of graphite (used in pencils) with numerous properties that could be valuable in a variety of applications,
including medicine, electronics and energy. Discovered only 11 years ago, graphene is one of the strongest materials in the world, highly conductive, flexible, and transparent.
However, current methods for production currently require toxic chemicals and lengthy and cumbersome processes that result in low yield that is not scalable for commercial applications.
The new revolutionary one-step high-yield generation process is detailed in the latest issue of Carbon,
and has succeeded in synthesizing few-layer (4-5) graphene in higher yields. It involves a novel optical system (originally invented by BGU Profs.
#Scientists print low cost radio frequency antenna with graphene ink (Nanowerk News) Scientists have moved graphene--the incredibly strong and conductive single-atom-thick sheet of carbon--a significant step along the path
Researchers from the University of Manchester, together with BGT Materials Limited, a graphene manufacturer in the United kingdom, have printed a radio frequency antenna using compressed graphene ink.
from AIP Publishing("Binder-free highly conductive graphene laminate for low cost printed radio frequency applications")."These scanning electron microscope images show the graphene ink after it was deposited
and after it was compressed (b). Compression makes the graphene nanoflakes more dense, which improves the electrical conductivity of the laminate.
/University of Manchester) The study demonstrates that printable graphene is now ready for commercial use in low-cost radio frequency applications,
"The point is that graphene is no longer just a scientific wonder. It will bring many new applications to our daily life very soon,"added Kostya S. Novoselov, from the School of Physics and Astronomy at the University of Manchester, who coordinated the project.
Graphene Gets Inked Since graphene was isolated first and tested in 2004, researchers have striven to make practical use of its amazing electrical and mechanical properties.
One of the first commercial products manufactured from graphene was conductive ink, which can be used to print circuits and other electronic components.
Graphene ink is generally low cost and mechanically flexible advantages it has over other types of conductive ink,
graphene flakes are mixed with a solvent, and sometimes a binder like ethyl cellulose is added to help the ink stick.
and the resulting"graphene laminate"was also almost two times more conductive than previous graphene ink made with a binder.
and More The researchers tested their compressed graphene laminate by printing a graphene antenna onto a piece of paper.
"Graphene based RFID tags can significantly reduce the cost thanks to a much simpler process and lower material cost,
The University of Manchester and BGT Materials Limited team has plans to further develop graphene enabled RFID tags,
and ultra-strong and lightweight structure, graphene has potential for many applications in electronics, energy, the environment,
Now a team of Northwestern University researchers has found a way to print three-dimensional structures with graphene nanoflakes.
The fast and efficient method could open up new opportunities for using graphene printed scaffolds regenerative engineering and other electronic or medical applications.
and her postdoctoral fellow Adam Jakus, the team developed a novel graphene-based ink that can be used to print large, robust 3-D structures."
"People have tried to print graphene before, "Shah said.""But it's been a mostly polymer composite with graphene making up less than 20 percent of the volume."
"With a volume so meager, those inks are unable to maintain many of graphene's celebrated properties.
But adding higher volumes of graphene flakes to the mix in these ink systems typically results in printed structures too brittle and fragile to manipulate.
Shah's ink is the best of both worlds. At 60-70 percent graphene, it preserves the material's unique properties,
including its electrical conductivity. And it's flexible and robust enough to print robust macroscopic structures.
the graphene flakes are mixed with a biocompatible elastomer and quickly evaporating solvents.""It's a liquid ink,
"Supported by a Google Gift and a Mccormick Research Catalyst Award, the research is described in the paper"Three-dimensional Printing Of high-Content Graphene Scaffolds for Electronic and Biomedical Applications","published in the April
An expert in biomaterials, Shah said 3-D printed graphene scaffolds could play a role in tissue engineering and regenerative medicine as well as in electronic devices.
and graphene's electrical conductivity most likely contributed to the scaffold's biological success."Cells conduct electricity inherently--especially neurons,
"The graphene-based ink directly follows work that Shah and her graduate student Alexandra Rutz completed earlier in the year to develop more cell-compatible, water-based, printable gels.
The new findings using a layer of one-atom-thick graphene deposited on top of a similar 2-D layer of a material called hexagonal boron nitride (hbn) are published in the journal Nano Letters("Tunable Lightatter
The hybrid material blocks light when a particular voltage is applied to the graphene while allowing a special kind of emission and propagation, called yperbolicity,
Light interaction with graphene produces particles called plasmons while light interacting with hbn produces phonons.
The properties of the graphene allow precise control over light, while hbn provides very strong confinement and guidance of the light.
says, his work represents significant progress on understanding tunable interactions of light in graphene-hbn.
The work is retty criticalfor providing the understanding needed to develop optoelectronic or photonic devices based on graphene and hbn,
Researchers measure graphene vibrations (Nanowerk News) An international research group led by scientists at the National Institute of Standards
and Technology's (NIST) Center for Nanoscale Science and Technology has developed a method for measuring crystal vibrations in graphene.
Understanding these vibrations is a critical step toward controlling future technologies based on graphene, a one-atom thick form of carbon.
Tunneling electrons from a scanning tunneling microscope tip excites phonons in graphene. The image shows the graphene lattice with blue arrows indicating the motion direction of that carbon atoms for one of the low energy phonon modes in graphene.
Image: Wyrick/NIST) They report their findings in the June 19, 2015, issue of Physical Review Letters("Strong Asymmetric Charge Carrier Dependence in Inelastic Electron Tunneling Spectroscopy of Graphene Phonons").
"Carbon atoms in graphene sheets are arranged in a regularly repeating honeycomb-like latticea two-dimensional crystal. Like other crystals,
The team was able to map all the graphene phonons this way, and their findings agreed well with their Georgia Tech collaborators'theoretical predictions.
when we switched the graphene charge carrier from holes to electronspositive to negative charges, "says Stroscio."
Image courtesy of Chongwu Zhou and Bilu Liu) The demand for a silicon material aided the discovery of graphene, a single layer of graphite
#Graphene flexes its electronic muscles Flexing graphene may be the most basic way to control its electrical properties, according to calculations by theoretical physicists at Rice university and in Russia.
and predictable in nanocones and should apply equally to other forms of graphene. The researchers discovered it may be possible to access
which the electronic properties of a sheet of graphene can be manipulated simply by twisting it a certain way.
The work will be of interest to those considering graphene elements in flexible touchscreens or memories that store bits by controlling electric dipole moments of carbon atoms
Perfect graphene an atom-thick sheet of carbon is a conductor, as its atomselectrical charges balance each other out across the plane.
But curvature in graphene compresses the electron clouds of the bonds on the concave side and stretches them on the convex side,
The researchers who published their results this month in the American Chemical Society Journal of Physical chemistry Letters discovered they could calculate the flexoelectric effect of graphene rolled into a cone of any size and length.
The researchers used density functional theory to compute dipole moments for individual atoms in a graphene lattice
and then figure out their cumulative effect They suggested their technique could be used to calculate the effect for graphene in other more complex shapes, like wrinkled sheets or distorted fullerenes,
several of which they also analyzed. hile the dipole moment is zero for flat graphene or cylindrical nanotubes,
Carbon nanotubes, seamless cylinders of graphene, do not display a total dipole moment, he said. While not zero, the vector-induced moments cancel each other out.
#Transition from 3 to 2 dimensions increases conduction Scientists from the MIPT Department of Molecular and Chemical Physics have described for the first time the behavior of electrons in a previously unstudied analogue of graphene, two-dimensional niobium telluride,
Andrei Geim and Konstantin Novoselov received the Nobel prize for their research on graphene, the most well-known among them.
For example, graphene is transparent, conducts current better than copper and has good thermal conductivity. Scientists believe that other types of two-dimensional materials may possess even more exotic properties.
#For faster, larger graphene add a liquid layer (Nanowerk News) Millimetre-sized crystals of high-quality graphene can be made in minutes instead of hours using a new scalable technique,
In just 15 minutes the method can produce large graphene crystals around 2-3 millimetres in size that it would take up to 19 hours to produce using current chemical vapour deposition (CVD) techniques in
which carbon in gas reacts with, for example, copper to form graphene. False colour image comparing graphene created on a pristine platinum surface with graphene created on the liquid layer of platinum silicide.
Image: University of Oxford) Graphene promises to be a'wonder material'for building new technologies because of its combination of strength, flexibility, electrical properties,
and chemical resistance. But this promise will only be realised if it can be produced cost-effectively on a commercial scale.
so that carbon atoms in methane gas brushing the surface are inclined more to form large flakes of graphene.
"Innovative substrate engineering for high quality 2d nanomaterials")'Not only can we make millimetre-sized graphene flakes in minutes
but this graphene is of a comparable quality to anything other methods are able to produce,
'Because it is allowed to grow naturally in single graphene crystals there are none of the grain boundaries that can adversely affect the mechanical and electrical properties of the material.'
and larger-scale graphene production for applications where very high quality graphene is needed.''Size-wise the new approach compares favourably with the common'Scotch tape method,'in
which a piece of tape is used to peel graphene fragments off a chunk of graphite,
But with the liquid layer of platinum silicide the researchers show that graphene crystals of 2-3 millimetres can be produced in minutes.
Out of all the techniques currently used to make different types of graphene CVD is the most promising for scaling up into a cost-effective industrial process.
with a thicker liquid layer to insulate it the graphene might not have to be removed from the substrate before it can be used-a costly
'This is a proof of principle study that shows that high-quality graphene, in the form of a single layer of carbon atoms, can be made to the size
and scale up this technique to produce flakes of graphene in large wafer-sized sheets. This invention adds to the growing patent portfolio of nanomaterials and their production technologies from Professor Nicole Grobert's Nanomaterials By design Group.
#An easy, scalable and direct method for synthesizing graphene in silicon microelectronics (Nanowerk News) In the last decade,
graphene has been studied intensively for its unique optical, mechanical, electrical and structural properties. The one-atom-thick carbon sheets could revolutionize the way electronic devices are manufactured
As a potential contact electrode and interconnection material, wafer-scale graphene could be an essential component in microelectronic circuits,
but most graphene fabrication methods are not compatible with silicon microelectronics, thus blocking graphene's leap from potential wonder material to actual profit-maker.
Now researchers from Korea University in Seoul, have developed an easy and microelectronics-compatible method to grow graphene
and have synthesized successfully wafer-scale (four inches in diameter), high-quality, multi-layer graphene on silicon substrates.
The method is based on an ion implantation technique, a process in which ions are accelerated under an electrical field and smashed into a semiconductor.
In a paper published this week in the journal Applied Physics Letters("Wafer-scale synthesis of multi-layer graphene by high-temperature carbon ion implantation"),from AIP Publishing
which takes graphene a step closer to commercial applications in silicon microelectronics. Wafer-scale (4 inch in diameter) synthesis of multi-layer graphene using high-temperature carbon ion implantation on nickel/Sio2/silicon.
Image: J. Kim/Korea University, Korea)" For integrating graphene into advanced silicon microelectronics, large-area graphene free of wrinkles, tears and residues must be deposited on silicon wafers at low temperatures,
which cannot be achieved with conventional graphene synthesis techniques as they often require high temperatures, "said Jihyun Kim, the team leader and a professor in the Department of Chemical and Biological engineering at Korea University."
"Our work shows that the carbon ion implantation technique has great potential for the direct synthesis of wafer-scale graphene for integrated circuit technologies."
graphene is considered now the thinnest, lightest and strongest material in the world. Graphene is completely flexible and transparent
while being inexpensive and nontoxic, and it can conduct electricity as well as copper, carrying electrons with almost no resistance even at room temperature, a property known as ballistic transport.
Graphene's unique optical, mechanical and electrical properties have lead to the one-atom-thick form of carbon being heralded as the next generation material for faster, smaller, cheaper and less power-hungry electronics."
"In silicon microelectronics, graphene is a potential contact electrode and an interconnection material linking semiconductor devices to form the desired electrical circuits,
"Thus, although the conventional graphene fabrication method of chemical vapor deposition is used widely for the large-area synthesis of graphene on copper and nickel films,
000 degrees Celsius and a subsequent transfer process of the graphene from the metallic film to the silicon."
"The transferred graphene on the target substrate often contains cracks, wrinkles and contaminants,"said Kim."
"Thus, we are motivated to develop a transfer-free method to directly synthesize high quality, multilayer graphene in silicon microelectronics."
The process is followed then by high temperature activation annealing (about 600 to 900 degrees Celsius) to form a honeycomb lattice of carbon atoms, a typical microscopic structure of graphene.
multi-layer graphene by varying the ambient pressure, ambient gas, temperature and time during the treatment.
allowing us to obtain graphene as large as the size of the silicon wafer over 300 millimeters in diameter,
and to control the thickness of the graphene for manufacturing production n
#Degrading BPA with visible light and a new hybrid nanoparticle photocatalyst Over the course of the last half century, BPA has gone from miracle to menace.
Toward Developing High-performance Graphene-Based Architectures for Energy storage devices"."The conundrum researchers have faced in developing miniature energy storage devices,
graphene, a conductive polymer and carbon nanotubes, which are atom-thick latticelike networks of carbon formed into cylinders.
Graphene, made from single atom-thick layers of graphite, was a suitable candidate due its electronic performance
The graphene in liquid form was mixed with the conductive polymer and reduced to solid and the carbon nanotubes carefully inserted between the graphene layers to form a self-assembled flat-packed,
or sophisticated equipment. ur graphene-based flexible composite is highly conductive, lightweight, is able to fold like a roll
if a GST layer were sandwiched between two thin graphite layers or even between two layers of graphene.
The sheets of cross-linked carbon atoms of which graphene is comprised fulfil the necessary requirements. The physicists in Ralph Ernstorfers group now want to experiment further with precisely these sandwiches of different materials.
Thats what Northeastern physicists Swastik Kar and Srinivas Sridhar found during their four-year project to modify graphene, a stronger-than-steel infinitesimally thin lattice of tightly packed carbon atoms.
the addition of boron and nitrogen to graphenes carbon to connote the conductivity necessary to produce an electrical insulator.
including those that are made with graphene electrodes a
#Nivolumab helps fight Cancerous Lung Tumors A trial has suggested that a therapy for lung cancer has the ability to double the life expectancy in patients.
#Graphene Filaments Provide Tunable On-Chip Light source Graphene Filaments Provide Tunable On-Chip Light Sourcenew YORK, June 15,
Researchers from the U s. and South korea collaborated to develop an on-chip visible light source using filaments made of graphene.
They attached small strips of graphene to metal electrodes, suspended the strips above a silicon substrate,
and graphene-based on-chip optical communications.""Schematic illustration of electrically biased suspended graphene and light emission from the center of the suspended graphene.
The ability of graphene to achieve such high temperatures without melting the substrate or the metal electrodes is due to another interesting property:
graphene becomes a much poorer conductor of heat. High temperatures are confined to a small ot spotin the center."
"At the highest temperatures, the electron temperature is much higher than that of acoustic vibrational modes of the graphene lattice,
as compared to graphene on a solid substrate.""By measuring the spectrum of the light emitted from the graphene,
the team was able to show that graphene was reaching temperatures of above 2500°Celsius,
hot enough to glow brightly.""The visible light from atomically thin graphene is so intense that it is visible even to the naked eye,
without any additional magnification,"said Young Duck Kim, a postdoctoral research scientist at Columbia. An optical image, top,
which the team discovered was due to interference between the light emitted directly from the graphene
and light reflecting off the silicon substrate and passing back through the graphene.""This is only possible
because graphene is transparent, unlike any conventional filament, and allows us to tune the emission spectrum by changing the distance to the substrate,
The team also demonstrated the scalability of their technique by realizing large-scale arrays of graphene light emitters grown with a chemical vapor deposition (CVD) process."
but using it in its pure form graphene and at its ultimate size limit one atom thick,
#Boron Turns Graphene into Blue light Emitter FRANKFURT, Germany, July 14, 2015 Chemists at Goethe University Frankfurt have developed a new class of organic luminescent materials through the targeted introduction of boron
atoms into graphene. The compounds exhibit an intense blue fluorescence and, consequently, are of interest for use as organic LEDS (OLEDS).
Within graphene, benzene rings are fused to form a honeycomb structure. Sections of this structure, referred to as nanographenes or polycyclic aromatic hydrocarbons (PAHS), play an integral role in organic electronics.
Hertz and Wagner anticipate that such materials like the graphene flakes they developed will be particularly suitable for use in portable electronic devices,
#Scientists Make Friction Disappear By Coating Diamonds With Graphene Diamonds are already one of the hardest natural substances known to science.
But combine them with graphene, and diamond nanoparticles are also incredibly slippery, which can be useful
When the diamond nanoparticles came in contact with the thin sheets of graphene (carbon that's only an atom thick) the graphene rolled up around the diamond nanoparticles,
It's specifically the interaction between graphene and diamond that makes the superlubricity possible right now,
including those that are made with graphene electrodes
#Gold Nano-Spirals Could Protect Against Identity Theft Most other investigators who have studied the remarkable properties of microscopic spirals have done so by arranging discrete nanoparticles in a spiral pattern:
#Laser-induced graphene'super'for electronics: Flexible 3-D supercapacitors tested Rice university scientists advanced their recent development of laser-induced graphene (LIG) by producing
and testing stacked, three-dimensional supercapacitors, energy storage devices that are important for portable, flexible electronics. The Rice lab of chemist James Tour discovered last year that firing a laser at an inexpensive polymer burned off other elements and left a film of porous graphene, the much-studied atom-thick
An electron microscope image shows the cross section of laser-induced graphene burned into both sides of a polyimide substrate.
since their work to make vertically aligned supercapacitors with laser-induced graphene on both sides of a polymer sheet.
But the graphene retains its ability to move electrons quickly and gives it the quick charge
#Defying the Achilles heel of'wonder material'graphene: Resilience to extreme conditions Researchers from the University of Exeter have discovered that Graphexeter--a material adapted from the'wonder material'graphene--can withstand prolonged exposure to both high temperature and humidity.
The research showed that the material could withstand relative humidity of up to 100 per cent at room temperature for 25 days as well as temperatures of up to 150c--or as high as 620c in vacuum.
The superior stability of Graphexeter as compared to graphene was unexpected since the molecules used to make Graphexeter (that is Fecl3) simply melt in air at room temperature.
At just one atom thick graphene is the thinnest substance capable of conducting electricity. It is very flexible
and engineers to adapt graphene for flexible electronics. This has been a challenge because of its sheet resistance
#Researchers use oxides to flip graphene conductivity A team of researchers from the University of Pennsylvania;
By demonstrating a new way to change the amount of electrons that reside in a given region within a piece of graphene they have a proof-of-principle in making the fundamental building blocks of semiconductor devices using the 2-D material.
Moreover their method enables this value to be tuned through the application of an electric field meaning graphene circuit elements made in this way could one day be rewired dynamically without physically altering the device.
Chemically doping graphene to achieve p -and n-type version of the material is possible but it means sacrificing some of its unique electrical properties.
but manufacturing and placing the necessary electrodes negates the advantages graphene's form factor provides.
We've come up with a non-destructive reversible way of doping Rappe said that doesn't involve any physical changes to the graphene.
The team's technique involves depositing a layer of graphene so it rests on but doesn't bond to a second material:
Here we have graphene standing by on the surface of the oxide but not binding to it.
or gaining electrons the graphene says'I can hold the electrons for you and they'll be right nearby.'
Because the lithium niobate domains can dictate the properties Shim said different regions of graphene can take on different character depending on the nature of the domain underneath.
That allows as we have demonstrated a simple means of creating a p-n junction or even an array of p-n junctions on a single flake of graphene.
Such an ability should facilitate advances in graphene that might be analogous to what p-n junctions and complementary circuitry has done for the current state-of-the-art semiconductor electronics.
What's even more exciting are the enabling of optoelectronics using graphene and the possibility of waveguiding lensing and periodically manipulating electrons confined in an atomically thin material.
and the charge carrier density of the graphene suspended over it. And because the oxide polarization can be altered easily the type
and extent of supported graphene doping can be altered along with it. You could come along with a tip that produces a certain electric field
and the graphene's charge density would reflect that change. You could make the graphene over that region p-type
or n-type and if you change your mind you can erase it and start again.
#Graphene quantum dot LEDS Graphene is a 2d carbon nanomaterial with many fascinating properties that can enable to creation of next-generation electronics.
However, it is known that graphene is not applicable to optical devices due to its lack of an electronic band gap.
The three-part structures consist of a base of graphene followed by atomic layers of either molybdenum disulfide (Mos2
#Graphene: Magnetic sensor 100 times more sensitive than silicon equivalent Scientists have created a graphene-based magnetic sensor 100 times more sensitive than an equivalent device based on silicon.
Bosch has long been involved in sensor technology, notably in the automotive sector. In 2008, the company expanded beyond its pressure, acceleration and gyroscopic motion sensors, to geomagnetic, temperature, humidity,
Interested in whether graphene could enable new applications and improved sensor performance, Bosch has been investigating the use of the two-dimensional material in its pressure,
Roelver cautioned that graphene-based sensor applications will require 5-10 years before they can compete with established technologies.
It is high carrier mobility that makes graphene useful in such applications, and the results achieved by the Bosch-led team confirm this.
Comparing and contrasting materials, Roelver in his Graphene Week presentation showed that the worst case graphene scenarios roughly match a silicon reference.
In short, graphene provides for a high-performance magnetic sensor with low power and footprint requirements. In terms of hard numbers
stressing that Bosch takes graphene very seriously indeed as a future commercial technology y
#First hospital light fixture to kill bacteria safely, continuously becomes commercially available in North america Indigo-Clean#is a light fixture manufactured through an exclusive licensing agreement with the University of Strathclyde in Glasgow, Scotland,
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