#Graphene reinvents the future For many scientists the discovery of one-atom-thick sheets of graphene is hugely significant something with the potential to affect just about every aspect of human activity and endeavour.
Graphene is hidden inside graphite an ore that has not been particularly sought after in the past. But a few years ago it revealed a secret.
At the molecular level it is a unique two-dimensional molecule: an electrically conductive latticelike layer just one carbon atom thick.
Graphene has usually cautious physicists and chemists itching with excitement mesmerised by the possibilities starting to take shape from flexible electronics embedded into clothing to biomedicine (imagine synthetic nerve cells) vastly superior forms of energy storage (tiny
But despite the extraordinary potential for graphene's properties the stumbling block has been to get it into a useable form.
Professor Li has invented a cost-effective and scalable way to split graphite into microscopic graphene sheets and dissolve them in water.
From this he has developed two new graphene technology platforms the starting points for developing commercial applications. One is a graphene gel that works as a supercapacitor electrode
and the second is a 3-D porous graphene foam. The graphene gel provides the same functionality as porous carbon a material currently sourced from coconut husks for use in supercapacitors and other energy conversion and storage technologies but with vastly enhanced performance.
Supercapacitors have an expanding range of applications as their capabilities increase from powering computer memory backup to powering electric vehicles.
Professor Li's team has also been able to give graphene a more functional 3-D form by engineering it into an elastic graphene foam that retains its extraordinary qualities.
Professor Li likened his developments to having invented bricks and said it was time to bring in architects
#Competition for graphene: Researchers demonstrate ultrafast charge transfer in new family of 2-D semiconductors A new argument has just been added to the growing case for graphene being bumped off its pedestal as the next big thing in the high-tech world by the two-dimensional semiconductors
known as MX2 materials. An international collaboration of researchers led by a scientist with the U s. Department of energy (DOE)' s Lawrence Berkeley National Laboratory (Berkeley Lab) has reported the first experimental observation of ultrafast charge transfer in photo-excited
These 2d semiconductors feature the same hexagonal"honeycombed"structure as graphene and superfast electrical conductance,
but, unlike graphene, they have natural energy bandgaps. This facilitates their application in transistors and other electronic devices because
unlike graphene, their electrical conductance can be switched off.""Combining different MX2 layers together allows one to control their physical properties,
#Scientists fabricate defect-free graphene set record reversible capacity for Co3o4 anode in Li-ion batteries Graphene has already been demonstrated to be useful in Li-ion batteries,
despite the fact that the graphene used often contains defects. Large-scale fabrication of graphene that is chemically pure, structurally uniform,
and size-tunable for battery applications has remained so far elusive. Now in a new study, scientists have developed a method to fabricate defect-free graphene (df-G) without any trace of structural damage.
Wrapping a large sheet of negatively charged df-G around a positively charged Co3o4 creates a very promising anode for high-performance Li-ion batteries.
current methods to fabricate high-quality graphene fall into two categories: mechanical approaches and chemical approaches. While mechanical cleavage provides high-quality graphene,
its low yield makes it insufficient for large-scale production. Chemical approaches, on the other hand, can produce bulk quantities
which causes the layers to expand away from each other to form graphene nanosheets that could later be cooled
because when a single graphene sheet is wrapped around a bundle of Co3o4 particles, the Co3o4 particles are prevented from becoming pulverized
whereas anodes with an imperfect graphene layer rapidly decrease with cycling. The large size of the graphene plays a key role in the performance
because a larger size provides a higher cycling stability of the nanosized anode materials by improving their mechanical integrity.
#Graphene rubber bands could stretch limits of current healthcare New research published today in the journal ACS Nano identifies a new type of sensor that can monitor body movements
Now researchers from the University of Surrey and Trinity college Dublin have treated for the first time common elastic bands with graphene to create a flexible sensor that is sensitive enough for medical use
By fusing this material with graphene -which imparts an electromechanical response on movement the team discovered that the material can be used as a sensor to measure a patient's breathing heart rate
but our graphene-infused rubber bands could really help to revolutionise remote healthcare said Dr Alan Dalton from the University of Surrey.
#New graphene framework bridges gap between traditional capacitors batteries Researchers at the California Nanosystems Institute (CNSI) at UCLA have set the stage for a watershed in mobile energy storage by using a special graphene material
The material, called a holey graphene framework, has perforated a three-dimensional structure characterized by tiny holes;
In their study, published online August 8 in the journal Nature Communications, the CNSI researchers led by Duan used a highly interconnected 3d holey graphene framework as the electrode material to create an EC with unprecedented performance.
Graphene research on the cusp of new energy capabilities (Phys. org) There remains a lot to learn on the frontiers of solar power research particularly
Under the guidance of Canada Research Chair in Materials science with Synchrotron radiation Dr. Alexander Moewes University of Saskatchewan researcher Adrian Hunt spent his Phd investigating graphene oxide a cutting-edge material that he hopes will shape the future
To understand graphene oxide it is best to start with pure graphene which is a single-layer sheet of carbon atoms in a honeycomb lattice that was made first in 2004 by Andre Geim
All of this makes graphene a great candidate for solar cells. In particular its transparency and conductivity mean that it solves two problems of solar cells:
whereas graphene could be very cheap. Carbon is said abundant Hunt. Although graphene is a great conductor it is not very good at collecting the electrical current produced inside the solar cell
which is why researchers like Hunt are investigating ways to modify graphene to make it more useful.
Graphene oxide the focus of Hunt's Phd work has forced oxygen into the carbon lattice which makes it much less conductive but more transparent and a better charge collector.
Whether or not it will solve the solar panel problem is yet to be seen and researchers in the field are building up their understanding of how the new material works.
and SGM beamlines at the Canadian Light source as well as a Beamline 8. 0. 1 at the Advanced Light source Hunt set out to learn more about how oxide groups attached to the graphene lattice changed it
and how in particular they interacted with charge-carrying graphene atoms. Graphene oxide is fairly chaotic. You don't get a nice simple structure that you can model really easily but
I wanted to model graphene oxide and understand the interplay of these parts. Previous models had seemed simplistic to Hunt
and he wanted a model that would reflect graphene oxide's true complexity. Each different part of the graphene oxide has a unique electronic signature.
Using the synchrotron Hunt could measure where electrons were on the graphene and how the different oxide groups modified that.
He showed that previous models were incorrect which he hopes will help improve understanding of the effects of small shifts in oxidization.
Moreover he studied how graphene oxide decays. Some of the oxide groups are not stable and can group together to tear the lattice;
others can react to make water. If graphene oxide device has water in it and it is heated up the water can actually burn the graphene oxide and produce carbon dioxide.
It's a pitfall that could be important to understand in the development of long-lasting solar cells where sun could provide risky heat into the equation.
More research like this will be the key to harnessing graphene for solar power as Hunt explains.
There's this complicated chain of interreactions that can happen over time and each one of those steps needs to be addressed
Super-stretchable yarn is made of graphene More information: Hunt Adrian Ernst Z. Kurmaev and Alex Moewes.
A Re evaluation of How Functional Groups Modify the Electronic Structure of Graphene oxide. Advanced Materials (2014.
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,
#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
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').
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.
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,
One the seamless connection between graphene covered copper foil and carbon nanotubes enhances the active material-current collector contact integrity
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 Bandgap Tuning in Bilayer Mos2 Physical Review Letters
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.
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."
#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
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,
#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,
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