Presenting their findings today 5 august 2014 in the journal Nanotechnology the researchers have demonstrated the material's superior performance compared to commercially available carbon graphene and carbon nanotubes.
and also had a higher amount of storage compared to graphene and carbon nanotubes as reported in previous studies.
Research on two-dimensional materials started with graphene, a material made of a single layer of carbon atoms.
analyse and improve ultra-thin layers by working with graphene. This know-how has now been applied to other ultra-thin materials."
#Surprise discovery could see graphene used to improve health (Phys. org) chance discovery about the'wonder material'graphene already exciting scientists because of its potential uses in electronics,
Researchers from Monash University have discovered that graphene oxide sheets can change structure to become liquid crystal droplets spontaneously and without any specialist equipment.
With graphene droplets now easy to produce, researchers say this opens up possibilities for its use in drug delivery and disease detection.
build on existing knowledge about graphene. One of the thinnest and strongest materials known to man,
graphene is a 2d sheet of carbon just one atom Thick with a'honeycomb'structure the'wonder material'is 100 times stronger than steel, highly conductive and flexible.
because graphene droplets change their structure in response to the presence of an external magnetic field,
"In contrast, graphene doesn't contain any magnetic properties. This combined with the fact that we have proved it can be changed into liquid crystal simply
"Usually atomisers and mechanical equipment are needed to change graphene into a spherical form. In this case all the team did was to put the graphene sheets in a solution to process it for industrial use.
Under certain PH conditions they found that graphene behaves like a polymer-changing shape by itself.
First author of the paper, Ms Rachel Tkacz from the Faculty of engineering, said the surprise discovery happened during routine tests."
"To be able to spontaneously change the structure of graphene from single sheets to a spherical assembly is hugely significant.
"Now we know that graphene-based assemblies can spontaneously change shape under certain conditions, we can apply this knowledge to see
This provides us with crucial information about the organisation of graphene sheets, enabling us to recognise these unique structures,
and Monash University and was the first linkage grant for graphene research in Australia s
#Nanoscale details of electrochemical reactions in electric vehicle battery materials Using a new method to track the electrochemical reactions in a common electric vehicle battery material under operating conditions,
#Existence of two-dimensional nanomaterial silicene questioned Sometimes scientific findings can shake the foundations of what was held once to be true causing us to step back
A recent study at the U s. Department of energy's Argonne National Laboratory has called into question the existence of silicene thought to be one of the world's newest and hottest two-dimensional nanomaterials.
#Graphene and related materials promise cheap flexible printed cameras Dr Felice Torrisi University Lecturer in Graphene technology has been awarded a Young International Researchers'Fellowship from the National Science Foundation
of China to look at how graphene and two-dimensional materials could enable printed and flexible eyes.
Graphene the ultimate thin membrane along with a wide range of two-dimensional (2d)- crystals (e g. hexagonal Boron nitride (h-BN) Molybdenum Disulfide (Mos2) and Tungsten Disulfide (WS2)) have changed radically the landscape
For example graphene is highly conductive flexible and transparent and it is superior to conductive polymers in terms of cost stability and performance;
In 2012 Drs Felice Torrisi Tawfique Hasan and Professor Andrea Ferrari at the Cambridge Graphene Centre invented a graphene ink
The graphene-based ink enables cost-effective printed electronics on plastic. Felice explains: Other conductive inks are made from precious metals such as silver
and process whereas graphene is both cheap environmentally stable and does not require much processing after printing.
and centrifugation process to unveil graphene potential in inks and coating for printed electronicsover the last two years Dr Torrisi
and the team at the Cambridge Graphene Centre have been looking to formulate a set of inks based on various 2d crystals setting a new platform for printed electronics.
based on graphene and 2d crystal-inks. The optical response of the printed 2d crystal inks combined with their flexibility on plastic substrate
#Cost-effective solvothermal synthesis of heteroatom (S or N)- doped graphene developed A research team led by group leader Yung-Eun Sung has announced that they have developed cost-effective technology to synthesize sulfur-doped and nitrogen-doped graphenes
and cost effectiveness processes that can produce heteroatom (S or N)- doped graphenes. Moreover these materials enhance the performance of secondary batteries
and nitrogen-doped graphenes by using a simple, single-step solvothermal method. These heteroatom-doped graphene exhibited high surface areas and high contents of heteroatoms.
In addition, the lithium-ion batteries that had applied modified graphenes to it, exhibited a higher capacity than the theoretical capacity of graphite
which was used previously in lithium-ion batteries. It presented high chemical stability which resulted in no capacity degradation in charge and discharge experiments.
The heteroatom-doped graphenes suggest the potential to be employed as an effective, alternative chemical material by demonstrating performance comparable to that of the expensive platinum catalyst used for the cathode of fuel cell batteries.
These atom-thin sheets including the famed super material graphene feature exceptional and untapped mechanical and electronic properties.
The team virtually examined this exotic phase transition in graphene boron nitride molybdenum disulfide and graphane all promising monolayer materials.
Within the honeycomb-like lattices of monolayers like graphene boron nitride and graphane the atoms rapidly vibrate in place.
In the case of graphene boron nitride and graphane the backbone of the perfect crystalline lattice distorted toward isolated hexagonal rings.
The soft mode distortion ended up breaking graphene boron nitride and molybdenum disulfide. As the monolayers were strained the energetic cost of changing the bond lengths became significantly weaker in other words under enough stress the emergent soft mode encourages the atoms to rearrange themselves into unstable configurations.
Our work demonstrates that the soft mode failure mechanism is not unique to graphene and suggests it might be an intrinsic feature of monolayer materials Isaacs said.
and exploit graphene and its cousins Isaacs said. For example we've been working with Columbia experimentalists who use a technique called'nanoindentation'to experimentally measure some of
Making graphene from plastic? Graphene is gaining heated attention dubbed a wonder material with great conductivity flexibility and durability.
However graphene is hard to come by due to the fact that its manufacturing process is complicated and mass production not possible.
Recently a domestic research team developed a carbon material without artificial defects commonly found during the production process of graphene
while maintaining its original characteristics. The newly developed material can be used as a substitute for graphene in solar cells and semiconductor chips.
Further the developed process is based on the continuous and mass-produced process of carbon fiber making it much easier for full-scale commercialization.
along with Dr. Seok-In Na at Chonbuk National University and Dr. Byoung Gak Kim at KRICT synthesized carbon nanosheets similar to graphene using polymer
To manufacture high quality graphene in large volume the CVD (chemical vapor deposition)* method is used widely.
and move the manufactured graphene to another board such as a solar cell substrate. In this process the quality quickly degrades as it is prone to wrinkles or cracks.
It is a method of manufacturing graphene on the board of metal film that serves as a catalyst.
and graphene has to be transported to another board. The research team developed carbon nanosheet in a two-step process which consists of coating the substrate with a plymer solution and heating.
Considering that the existing process consists of 8 steps to manufacture graphene the new method makes it much simpler.
since the new process bypasses the steps that are prone to formation of defects such as elimination of the metal substrate or transfer of graphene to another board.
The final product is as effective as graphene. Dr. Han Ik Joh at KIST said It is expected to be applied for commercialization of transparent and conductive 2d carbon materials without difficulty
Nam first had the idea for using Shrinky Dinks plastic to assemble nanomaterials after seeing a microfluidics device that used channels made of shrinking plastic.
who also serves the president of Fullerene, Carbon nanotubes, and Graphene research Society of Japan. Single-walled carbon nanotube (SWNT
which can be considered as a seamlesscylinder formed by rolling a piece of graphene, may be either metallic
or semiconducting depending on the manner of rolling denoted as (n m)( or the'chirality').'Relying on the fantastic structure and property, especially the extremely high mobility for both electrons and holes,
and graphene for additional resources and detailed road mapping for ITRS as promising technologies targeting commercial demonstration in the next 10-15 year horizon.
#Lab unzips nanotubes into ribbons by shooting them at a target (Phys. org) Carbon nanotubes unzipped into graphene nanoribbons by a chemical process invented at Rice university are finding use in all kinds of projects
One-step chemical-free clean and high-quality graphene nanoribbons can be produced using our method. They're potential candidates for next-generation electronic materials he said.
Like tiny submarines these versatile nanocarriers can navigate in the watery environment surrounding cells and transport their guest molecules through the membrane of living cells to sequentially deliver their cargo.
For practical applications these nanocarriers are highly desirable explains Francisco Raymo professor of chemistry in the University of Miami College of Arts and Sciences and lead investigator of this project.
The new nanocarriers are15 nanometers in diameter. They are made supramolecular constructs up of building blocks called amphiphilic polymers.
These nanocarriers hold the guest molecules within the confines of their water-insoluble interior and use their water-soluble exterior to travel through an aqueous environment.
#Smart gating nanochannels for confined water developed Confined water exists widely and plays important roles in natural environments, particularly inside biological nanochannels.
Professor Lei Jiang and his group from State Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, set out to study this unified bionic frontier.
After several years of innovative research, they developed a series of biomimetic nanochannels, delivered a strategy for the design
and construction of smart nanochannels and applied the nanochannels in energy conversion systems. The author thought the inner surface property was the base for confined transportation.
entitled"Construction of biomimetic smart nanochannels for confined water",was published in National Science Review. Nature has inspired always greatly technology, engineering and significant inventions.
They also studied confined water existing in nanochannel, which included the construction and application of bio-inspired nanochannels.
In this review Prof. Jiang expatiated the confined water that exists in one-dimensional micro/nano composite structures in detail, particularly inside biological nanochannels.
Using these nanochannels as inspiration, they provided a strategy for the design and construction of biomimetic smart nanochannels.
Importantly, they have applied the abiotic analogs to energy conversion systems. The confined water, that is water confined in micro-or mesopores,
not only plays an important role in maintaining the existence and development of living organisms, but also concerns the sustainable development of human society.
However if it is parallel to the target upon impact the nanotube will unzip resulting in a 2d graphene nanoribbon.
Unzipping carbon nanotubes to create 2d graphene nanoribbons is very useful in nanoscience but until now it has typically been achieved with chemical contaminants that leave back contaminants.
By demonstrating for the first time that nanotubes can be unzipped quickly through mechanical means the new study offers a clean-cut a clean chemical-free way to produce high-quality graphene nanoribbons.
As the researchers explained graphene nanoribbons have certain advantages over both nanotubes and graphene that make them attractive for applications.
Graphene nanoribbons are good candidates for active materials in electronics being the channel of field-effect transistors coauthor Dr. Robert Vajtai at Rice university told Phys. org.
They are superior to carbon nanotubes as their bandgap is more predictable. Also they are superior to graphene itself as graphene has no bandgap
but making a nanometer scale narrow stripe of it opens the bandgap because of quantum confinement so it is a semiconductor.
Hybrid nanotube-graphene material promises to simplify manufacturing More information: Sehmus Ozden et al. Unzipping Carbon nanotubes at High Impact.
#Super-stretchable yarn is made of graphene A simple, scalable method of making strong, stretchable graphene oxide fibers that are scrolled easily into yarns
and have strengths approaching that of Kevlar is possible, according to Penn State and Shinshu University, Japan, researchers."
"We found this graphene oxide fiber was very strong, much better than other carbon fibers,"said Mauricio Terrones, professor of physics, chemistry and materials science and engineering, Penn State."
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. The researchers believe that the material lends itself to many kinds of highly sensitive sensors.
The researchers made a thin film of graphene oxide by chemically exfoliating graphite into graphene flakes,
"said physicist Oleg Gang who led the study at the Center for Functional Nanomaterials (CFN) at the U s. Department of energy's Brookhaven National Laboratory.
One the seamless connection between graphene covered copper foil and carbon nanotubes enhances the active material-current collector contact integrity
For criminals to circumvent the process they would have to somehow find out which nanomaterials were added to a product to create its unique thermal signature then add the right mix of nanoparticles to their own counterfeit product to recreate it no easy feat.
#Bending helps to control nanomaterials A new remedy has been found to tackle the difficulty of controlling layered nanomaterials.
The group investigated the Van der waals nanomaterials which consist of stacked and loosely bound two-dimensional atomic layers.
Proposed graphene cardboard has highly tunable properties More information: P. Koskinen I. Fampiou A. Ramasubramaniam Density-Functional Tight-Binding Simulations of Curvature-Controlled Layer Decoupling and Band-Gap Tuning in Bilayer Mos2 Physical Review
dull grey wafers that graduate student Andrew Westover and Assistant professor of Mechanical engineering Cary Pint have made in Vanderbilt's Nanomaterials
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 electrolyte paste in a battery.
"Combining nanoporous material with the polymer electrolyte bonds the layers together tighter than superglue.""The use of silicon in structural supercapacitors is suited best for consumer electronics and solar cells,
This one packs an interconnected network of graphene and carbon nanotubes so tightly that it stores energy comparable to some thin-film lithium batteriesn area where batteries have held traditionally a large advantage.
A solution containing acid-oxidized single-wall nanotubes graphene oxide and ethylenediamine which promotes synthesis and dopes graphene with nitrogen is pumped through a flexible narrow reinforced tube called a capillary column and heated in an oven for six hours.
Sheets of graphene one to a few atoms thick and aligned single-walled carbon nanotubes self-assemble into an interconnected prorous network that run the length of the fiber.
The arrangement provides huge amounts of accessible surface area96 square meters per gram of hybrid fiberor the transport and storage of charges.
High-performance low-cost ultracapacitors built with graphene and carbon nanotubes More information: Paper: Scalable synthesis of hierarchically structured carbon nanotuberaphene fibres for capacitive energy storage dx. doi. org/10.1038/nnano. 2014.9 n
#Graphene photonics breakthrough promises fast-speed low-cost communications Swinburne researchers have developed a high-quality continuous graphene oxide thin film that shows potential for ultrafast telecommunications.
Graphene is derived from carbon, the fourth most abundant element on earth. It has many useful properties,
To create the thin film the researchers spin coated graphene oxide solution to a glass surface.
Using a laser as a pen they created microstructures on the graphene oxide film to tune the nonlinearity of the material."
The new MIT technology could enable very high-speed inertial imaging as cells flow through a channel. he suspended nanochannel technology pioneered by the Manalis group is remarkable
as they flow through the nanochannels. analislab is also using the new technique to study how cellsdensities change as they pass through constrictions.
It may be used to create alloy nanomaterials for solar cells, heterogeneous catalysts for a variety of chemical reactions, and energy storage devices."
New nanomaterials will boost renewable energy More information:""Soft Landing of Bare Nanoparticles with Controlled Size, Composition, and Morphology."
#Researchers Reveal Why Black Phosphorus May Surpass Graphene In a newly published study, researchers from the Pohang University of Science and Technology detail how they were able to turn black phosphorus into a superior conductor that can be mass produced for electronic and optoelectronics devices.
a layered form of carbon atoms constructed to resemble honeycomb, called graphene. Graphene was heralded globally as a wonder-material thanks to the work of two British scientists who won the Nobel prize for Physics for their research on it.
Graphene is extremely thin and has remarkable attributes. It is stronger than steel yet many times lighter
more conductive than copper and more flexible than rubber. All these properties combined make it a tremendous conductor of heat and electricity.
graphene has no band gap. Stepping stones to a Unique Statea material band gap is fundamental to determining its electrical conductivity.
Graphene has a band gap of zero in its natural state, however, and so acts like a conductor;
Like graphene, BP is a semiconductor and also cheap to mass produce. The one big difference between the two is BP natural band gap
therefore we tuned BP band gap to resemble the natural state of graphene, a unique state of matter that is different from conventional semiconductors. he potential for this new improved form of black phosphorus is beyond anything the Korean team hoped for,
#Pillared Graphene structures Gain Strength, Toughness and Ductility In a newly published study, scientists from Rice university reveal that putting nanotube pillars between sheets of graphene could create hybrid structures with a unique balance of strength, toughness
Carbon nanomaterials are common now as flat sheets, nanotubes and spheres, and theye being eyed for use as building blocks in hybrid structures with unique properties for electronics,
particularly between carbon nanotubes and graphene, would affect the final hybrid properties in all directions. They found that introducing junctions would add extra flexibility
when compared with materials made of layered graphene. Their results appear this week in the journal Carbon.
graphene is a rolled out sheet of the same. Both are super-strong and excel at transmitting electrons and heat.
the way the atoms are arranged can influence all those properties. ome labs are actively trying to make these materials or measure properties like the strength of single nanotubes and graphene sheets,
and quantitatively predict the properties of hybrid versions of graphene and nanotubes. These hybrid structures impart new properties
and functionality that are absent in their parent structures graphene and nanotubes. To that end the lab assembled three-dimensional computer models of illared graphene nanostructures, akin to the boron nitride structures modeled in a previous study to analyze heat transfer between layers. his time we were interested in a comprehensive understanding of the elastic and inelastic properties
of 3-D carbon materials to test their mechanical strength and deformation mechanisms, Shahsavari said. e compared our 3-D hybrid structures with the properties of 2-D stacked graphene sheets and 1-D carbon nanotubes.
Layered sheets of graphene keep their properties in-plane, but exhibit little stiffness or thermal conductance from sheet to sheet,
he said. But pillared graphene models showed far better strength and stiffness and a 42 percent improvement in out-of-plane ductility,
the ability to deform under stress without breaking. The latter allows pillared graphene to exhibit remarkable toughness along out-of-plane directions, a feature that is not possible in 2-D stacked graphene sheets or 1-D carbon nanotubes,
Shahsavari said. The researchers calculated how the atomsinherent energies force hexagons to take on or lose atoms to neighboring rings,
Turning the nanotubes in a way that forced wrinkles in the graphene sheets added further flexibility and shear compliance,
That leads to the notion the hybrids can be tuned to fail under particular circumstances. his is the first time anyone has created such a comprehensive atomistic ensto look at the junction-mediated properties of 3-D carbon nanomaterials
#Graphene"Decorated"With Lithium Becomes a Superconductor Graphene is a conductor unlike anything seen before.
nobody had been able to make graphene behave as a superconductor, until now. An international research team from Canada and Germany has been able to demonstrate that graphene can be made to behave as a superconductor
when it doped with lithium atoms. The researchers believe that this new property could lead to a new generation of superconducting nanoscale devices.
Graphene is not naturally a superconductor, and neither is its three-dimensional sourceraphite. However, it was demonstrated a decade ago that graphite could be induced into behaving like a superconductor.
it should be with graphene, right? Other research groups believed so and developed computer models demonstrating that combining graphene with lithium might do the trick.
Lithium, they predicted, could contribute a lot of phonons to the graphene electrons. In a research paper available on arxiv, the researchers demonstrated in physical experiments that the computer models were indeed correct in their predictions.
Andrea Damascelli at the University of British Colombia in Vancouver, together with collaborators in Europe, grew layers of graphene on silicon-carbide substrates,
then deposited lithium atoms onto the graphene in a vacuum at 8 K, creating a version of graphene known as ecoratedgraphene.
In the testing and measuring of their material the researchers found that the electrons slowed down as they travelled through the lattice,
which they believe to be the result of enhanced electronhonon coupling. The key observation was increased that this number of coupled pairs led to superconductivity,
#Graphene and Perovskite Lead to Inexpensive and Highly Efficient Solar cells Perovskite is the new buzzword in photovoltaics.
And graphene is the buzzword for just about every other high-tech application, including photovoltaics. Now researchers at Hong kong Polytechnic University have combined these two materials to make a semitransparent solar cell capable of power conversion efficiencies around 12 percent, a significant improvement over the roughly 7-percent efficiency of traditional
and the graphene acts as the transparent electrode material. Graphene has long been pursued as a potential replacement for indium tin oxide (ITO) as a transparent electrode material for displays.
Here again, graphene transparency, high conductivity, and potentially low cost seemed attractive to the researchers. The researchers improved on the conductivity of the graphene by coating it with a thin layer of a polymer that also served as an adhesion layer to the perovskite active layer during the lamination process.
The researchers were able to improve the energy conversion capability of the solar cells by employing a multi-layer chemical vapor deposition process in
which the graphene formed the top transparent electrodes. This approach maintained the transparency of the electrodes
while increasing their sheet resistance. A big concern for the researchers was lowering costs. They claim that their solar cells cost less than US$. 06/watt,
because the mechanical flexibility of the graphene enables the possibility of roll-to-roll processing o
#Graphene and Perovskite Lead to Inexpensive and Highly Efficient Solar cells Perovskite is the new buzzword in photovoltaics.
And graphene is the buzzword for just about every other high-tech application, including photovoltaics. Now researchers at Hong kong Polytechnic University have combined these two materials to make a semitransparent solar cell capable of power conversion efficiencies around 12 percent, a significant improvement over the roughly 7-percent efficiency of traditional
and the graphene acts as the transparent electrode material. Graphene has long been pursued as a potential replacement for indium tin oxide (ITO) as a transparent electrode material for displays.
Here again, graphene transparency, high conductivity, and potentially low cost seemed attractive to the researchers. The researchers improved on the conductivity of the graphene by coating it with a thin layer of a polymer that also served as an adhesion layer to the perovskite active layer during the lamination process.
The researchers were able to improve the energy conversion capability of the solar cells by employing a multi-layer chemical vapor deposition process in
which the graphene formed the top transparent electrodes. This approach maintained the transparency of the electrodes
while increasing their sheet resistance. A big concern for the researchers was lowering costs. They claim that their solar cells cost less than US$. 06/watt,
because the mechanical flexibility of the graphene enables the possibility of roll-to-roll processing i
#Graphene's Killer App? Measuring Electrical resistance Graphene merits in electronic devices and as a light bulb coating are still being debated.
But new results suggest the atom-thick carbon sheet has one clear advantage: precise but practical calibrations of electrical resistance.
Researchers have suspected long that the unique behavior of electrons in graphene, namely the big spacing between electron energy levels when the material is exposed to a magnetic field,
In August, Jan-Theodoor Janssen at the UK National Physical Laboratory and colleagues reported a way to build a graphene resistance standard that can operate at a higher temperature and lower magnetic field.
The french team constructed its resistance device from a high-quality sheet of graphene grown on a silicon carbide wafer.
The temperature the graphene device operates at is high enough that a lab could accurately measure resistance without needing liquid helium as a refrigerant. hese results support graphene as the material of choice for the next generation of easy-to-use, helium-free,
Graphene could also help bring about the realization of a simplified ampere, one of the seven SI base units.
which is also investigating graphene potential as a resistance standard. f we are to make watt balances available to everyone,
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