Graphene’s magic is in the defects


Graphene's magic is in the defects
NYU researchers discovered how to predict the sensitivity of graphene electrodes — potentially paving the way to industrial-scale production of the ultra-small sensors: The density of intentionally introduced point defects is directly …more

A team of researchers at the New York University Tandon School of Engineering and NYU Center for Neural Science has solved a longstanding puzzle of how to build ultra-sensitive, ultra-small electrochemical sensors with homogenous and predictable properties by discovering how to engineer graphene structure on an atomic level.

Finely tuned electrochemical sensors (also referred to as electrodes) that are as small as biological cells are prized for medical diagnostics and environmental monitoring systems. Demand has spurred efforts to develop nanoengineered carbon-based electrodes, which offer unmatched electronic, thermal, and mechanical properties. Yet these efforts have long been stymied by the lack of quantitative principles to guide the precise engineering of the sensitivity to biochemical molecules.

Davood Shahrjerdi, an assistant professor of electrical and computer engineering at NYU Tandon, and Roozbeh Kiani, an assistant professor of neural science and psychology at the Center for Neural Science, Faculty of Arts and Science, have revealed the relationship between various structural defects in and the sensitivity of the electrodes made of it. This discovery opens the door for the precise engineering and industrial-scale production of homogeneous arrays of graphene electrodes. The researchers detail their study in a paper published today in the journal Advanced Materials.

Graphene is a single, atom-thin sheet of carbon. There is a traditional consensus that structural defects in graphene can generally enhance the sensitivity of electrodes constructed from it.  However, a firm understanding of the relationship between various structural defects and the sensitivity has long eluded researchers. This information is particularly vital for tuning the density of different defects in graphene in order to achieve a desired level of sensitivity.

“Until now, achieving a desired sensitivity effect was akin to voodoo or alchemy—oftentimes, we weren’t sure why a certain approach yielded a more or less sensitive electrode,” Shahrjerdi said. “By systematically studying the influence of various types and densities of material defects on the electrode’s sensitivity, we created a physics-based microscopic model that replaces superstition with scientific insight.”

In a surprise finding, the researchers discovered that only one group of defects in graphene’s structure—point defects—significantly impacts electrode sensitivity, which increases linearly with the average density of these defects, within a certain range. “If we optimize these point defects in number and density, we can create an electrode that is up to 20 times more sensitive than conventional electrodes,” Kiani explained.

These findings stand to impact both the fabrication of and applications for graphene-based electrodes. Today’s carbon-based electrodes are calibrated for sensitivity post-fabrication, a time-consuming process that hampers large-scale production, but the researchers’ findings will allow for the precise engineering of the sensitivity during the material synthesis, thereby enabling industrial-scale production of carbon-based electrodes with reliable and reproducible sensitivity.

Currently, carbon-based electrodes are impractical for any application that requires a dense array of sensors: The results are unreliable due to large variations of the electrode-to-electrode within the array. These new findings will enable the use of ultra-small carbon-based electrodes with homogeneous and extraordinarily high sensitivities in next-generation neural probes and multiplexed “lab-on-a-chip” platforms for medical diagnostics and drug development, and they may replace optical methods for measuring biological samples including DNA.

Scientists Have Found a Way to Use Graphene As… Hair Dye


That sounds awesome and expensive.

Graphene is definitely a wonder material – you can use it to make filthy water drinkable, feed it to spiders to make the strongest material on Earth, or hit it with a bullet to turn it into diamond.

main article image

You know, just everyday stuff.

The newest application for graphene isn’t quite as world-changing, but it’s still pretty amazing – making ‘chemical free’ black hair dye.

The researchers behind this feat claim that it’s a less damaging way to colour hair, which makes sense when you understand how regular hair dye works.

The outside of the hair, called the cuticle, is made of cells that overlap in a scale-like way.

(Jae Hong Ji, et al/Wikimedia)

When you dye the hair, you actually have to open those scales with chemical compounds in order to deposit the dye inside.

“Your hair is covered in these cuticle scales like the scales of a fish, and people have to use ammonia or organic amines to lift the scales and allow dye molecules to get inside a lot quicker,” says senior author Jiaxing Huang, a materials scientist at Northwestern University.

This is why the more the hair is dyed, the more damage it can potentially do, leaving your locks dry and brittle.

Enter everyone’s favourite: graphene.

Instead of penetrating the hair, graphene actually just coats it, in the same way that wash-out dyes do. But the difference is that the graphene hair colour stays in long enough to be considered permanent – at least 30 washes.

What makes it possible is the thin sheet-like structure of the wonder material.

“Imagine a piece of paper. A business card is very rigid and doesn’t flex by itself. But if you take a much bigger sheet of newspaper – if you still can find one nowadays – it can bend easily. This makes graphene sheets a good coating material,” Huang says.

When comparing graphene to other temporary hair dye particles, such as carbon black or iron oxide, there’s basically no competition, according to the team.

“It’s similar to the difference between a wet paper towel and a tennis ball,” he said.

“The paper towel is going to wrap and stick much better. The ball-like particles are much more easily removed with shampoo.”

At this point you may be thinking about how expensive graphene is, and you’re totally right. But while it’s hard and pricey to make high-quality graphene for scientific purposes, some of it could be cheap enough to end up as hair dye.

“You can have graphene that is too lousy for higher-end electronic applications, but it’s perfectly okay for this,” says Huang.

“I think that this could happen a lot sooner than many of the other proposed applications.”

It works, so when will you be seeing graphene hair dye on your supermarket shelves?

Although the team is super excited about it, it’s important to note that it’s still definitely in the research phase. But it’s definitely an interesting way of using our most exciting wonder material.

“This is an idea that was inspired by curiosity. It was very fun to do, but it didn’t sound very big and noble when we started working on it,” Huang says.

“But after we deep-dived into studying hair dyes, we realized that, wow, this is actually not at all a small problem. And it’s one that graphene could really help to solve.”

This New Graphene Invention Makes Filthy Seawater Drinkable in One Simple Step


2.1 billion people still don’t have safe drinking water.

Using a type of graphene called Graphair, scientists from Australia have created a water filter that can make highly polluted seawater drinkable after just one pass.

The technology could be used to cheaply provide safe drinking water to regions of the world without access to it.

“Almost a third of the world’s population, some 2.1 billion people, don’t have clean and safe drinking water,” said lead author Dong Han Seo.

“As a result, millions – mostly children – die from diseases associated with inadequate water supply, sanitation and hygiene every year. In Graphair we’ve found a perfect filter for water purification.

“It can replace the complex, time consuming and multi-stage processes currently needed with a single step.”

Developed by researchers at the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Graphair is a form of graphene made out of soybean oil.

Graphene – a one-atom-thick, ultrastrong carbon material – might be touted as a supermaterial, but it’s been relatively expensive to produce, which has been limiting its use in broader applications.

Graphair is cheaper and simpler to produce than more traditional graphene manufacturing methods, while retaining the properties of graphene.

One of those properties is hydrophobia – graphene repels water.

To turn it into a filter, the researchers developed a graphene film with microscopic nanochannels; these allow the water through, but stop larger pollutants with larger molecules.

Then the team overlaid their new film on a typical, commercial-grade water filtration membrane to do some tests.

When used by itself, a water filtration membrane becomes coated with contaminants, blocking the pores that allow the water through. The researchers found that during their tests using highly polluted Sydney Harbour water, a normal water filter’s filtration rate halved without the graphene film.

Then the Graphair was added to the filter. The team found that the combination filter screened out more contaminants – 99 percent of them – faster than the conventional filter. And it continued to work even when coated with pollutants, the researchers said.

This eliminates a step from other filtration methods – removing the contaminants from the water before passing it through the membrane to prevent them from coating it.

This is a similar result to one found last year, where minuscule pores in a graphene filter were able to prevent salt from seawater from passing through – and allow water through faster.

“This technology can create clean drinking water, regardless of how dirty it is, in a single step,” Seo said.

“All that’s needed is heat, our graphene, a membrane filter, and a small water pump. We’re hoping to commence field trials in a developing world community next year.”

Eventually, they believe that the technology could be used for household and even town-based water filtration, as well as seawater and industrial wastewater treatment.

This Might Be The Strongest And Lightest Material on Earth


10 times stronger than steel, with only 5 percent of its density.

For years, researchers have known that carbon, when arranged in a certain way, can be very strong.

Case in point: graphene. Graphene, which was heretofore, the strongest material known to man, is made from an extremely thin sheet of carbon atoms arranged in two dimensions.

But there’s one drawback: while notable for its thinness and unique electrical properties, it’s very difficult to create useful, three-dimensional materials out of graphene.

In January last year, a team of MIT researchers discovered that taking small flakes of graphene and fusing them following a mesh-like structure not only retains the material’s strength, but the graphene also remains porous.

Based on experiments conducted on 3D printed models, researchers have determined that this material, with its distinct geometry, is actually stronger than graphene – making it 10 times stronger than steel, with only 5 percent of its density.

The discovery of a material that is extremely strong but exceptionally lightweight will have numerous applications.

As MIT reports:

“The new findings show that the crucial aspect of the new 3-D forms has more to do with their unusual geometrical configuration than with the material itself, which suggests that similar strong, lightweight materials could be made from a variety of materials by creating similar geometric features.”

Below you can see a simulation results of compression (top left and i) and tensile (bottom left and ii) tests on 3D graphene:

“You could either use the real graphene material or use the geometry we discovered with other materials, like polymers or metals,” said Markus Buehler, head of MIT’s Department of Civil and Environmental Engineering (CEE), and the McAfee Professor of Engineering.

“You can replace the material itself with anything. The geometry is the dominant factor. It’s something that has the potential to transfer to many things.”

Construction may prove to be easier, given that the material used will now be significantly lighter. Because of its porous nature, it may also be applied to filtration systems.

This research, said Huajian Gao, a professor of engineering at Brown University, who was not involved in this work, “shows a promising direction of bringing the strength of 2D materials and the power of material architecture design together”.

Has Nanotechnology Already Reached Its Limit?


Article Image

What’s the Latest Development?

Professor Mike Kelly at Cambridge University’s Centre for Advanced Photonics and Electronics has stunned a budding nanotechnology industry by saying that structures with a diameter of three nanometres or less cannot be mass-produced. “This statement raises a major question concerning the billions of dollars that are poured into nanotechnology each year in the hope that the latest technology developed in the lab can make the transition to a manufactured product on the market,” according to Phys Org.

What’s the Big Idea?

Nanotechnology is built on the ability to control and manipulate matter at the atomic and molecular level and has already had far reaching applications including helping drugs to be delivered into patients’ bodies, improving food packaging and increasing the efficiency of solar panels. It is a budding industry that, given recent success in the laboratory—the 2010 Nobel Prize was given to two scientists for their experiments with graphene, an extremely tough one-atom-think nanostructure—holds large commercial potential.

The ‘Miracle Material’ Strikes Again. Graphene Can Turn CO2 Into Liquid Fuel


IN BRIEF
  • Scientists have discovered that “doping” graphene with nitrogen allows it to be an efficient electrocatalyst which can convert environmentally harmful CO2 into useful fuels.
  • The technology is far from being ready for large scale application, yet the research is useful in the development of new catalysts that could provide a variety of useful applications in the future.

EFFECTIVE ELECTROCATALYST

Graphene is quickly becoming a Swiss Army knife of materials when it comes to the ever expanding applications. It can radically change our world with its fascinating applications in medicine and electronics. Now, this wonder material just got more wonderful. Researchers from Rice University expanded graphene’s electricity-wielding capabilities: it can now convert carbon dioxide (CO2) into liquid fuels.

Specifically, the researchers discovered that nanometer nitrogen-doped graphene quantum dots (NGQDs) can be electrocatalysts that trigger CO2 electroreduction into high-energy liquid fuels — creating ethylene and ethanol. They describe the process in a study published in Nature Communications

“Carbon is typically not a catalyst,” said lead researcher Pulickel Ajayan, and graphene is largely made up of carbon. So they had to add nitrogen atoms into the graphene dots, which trigger chemical reactions as a response to electric current and carbon dioxide — although exactly how it works is still a mystery. “So it’s been a puzzle, and though people have written a lot of papers in the last five to 10 years on doped and defective carbon being catalytic, the puzzle is not really solved,” said Ajavan.

Credits: Ajayan Group/Rice University
 

A FUEL TOOL KIT

NGQDs seem to be really good electrocatalysts, capable of performing as well as copper. It can reduce the level of released CO2 by 90%, with 45% converted into small amounts of ethylene and ethanol. It produces fuels and can lower CO2, and it can sustain this for a substantial amount of time.

Once explored and realized, electrocatalysts like NGQDs could be developed into a potential fuel source while at the same time reducing the amount of CO2 that enters the atmosphere. There’s still much to be done before commercialization of such a product and the Rice researchers know it.

“I think what we found is fundamentally interesting, because it provides an efficient pathway to screen new types of catalysts to convert carbon dioxide to higher-value products,” Ajayan said. NGQDs won’t find their way into real-world applications just yet, especially since prescribed industry practice uses thermal catalysis and not electrocatalysis to create fuel, as they scale better.

“For that reason, companies probably won’t use it any time soon for large-scale production,” said Ajayan. “But electrocatalysis can be easily done in the lab, and we showed it will be useful in the development of new catalysts.” Ajayan’s team will continue their research.

Graphene can turn CO2 into liquid fluid.


IN BRIEF
  • Scientists have discovered that “doping” graphene with nitrogen allows it to be an efficient electrocatalyst which can convert environmentally harmful CO2 into useful fuels.
  • The technology is far from being ready for large scale application, yet the research is useful in the development of new catalysts that could provide a variety of useful applications in the future.

EFFECTIVE ELECTROCATALYST

Graphene is quickly becoming a Swiss Army knife of materials when it comes to the ever expanding applications. It can radically change our world with its fascinating applications in medicine and electronics. Now, this wonder material just got more wonderful. Researchers from Rice University expanded graphene’s electricity-wielding capabilities: it can now convert carbon dioxide (CO2) into liquid fuels.

Specifically, the researchers discovered that nanometer nitrogen-doped graphene quantum dots (NGQDs) can be electrocatalysts that trigger CO2 electroreduction into high-energy liquid fuels — creating ethylene and ethanol. They describe the process in a study published in Nature Communications

“Carbon is typically not a catalyst,” said lead researcher Pulickel Ajayan, and graphene is largely made up of carbon. So they had to add nitrogen atoms into the graphene dots, which trigger chemical reactions as a response to electric current and carbon dioxide — although exactly how it works is still a mystery. “So it’s been a puzzle, and though people have written a lot of papers in the last five to 10 years on doped and defective carbon being catalytic, the puzzle is not really solved,” said Ajavan.

Credits: Ajayan Group/Rice University

A FUEL TOOL KIT

NGQDs seem to be really good electrocatalysts, capable of performing as well as copper. It can reduce the level of released CO2 by 90%, with 45% converted into small amounts of ethylene and ethanol. It produces fuels and can lower CO2, and it can sustain this for a substantial amount of time.

Once explored and realized, electrocatalysts like NGQDs could be developed into a potential fuel source while at the same time reducing the amount of CO2 that enters the atmosphere. There’s still much to be done before commercialization of such a product and the Rice researchers know it.

“I think what we found is fundamentally interesting, because it provides an efficient pathway to screen new types of catalysts to convert carbon dioxide to higher-value products,” Ajayan said. NGQDs won’t find their way into real-world applications just yet, especially since prescribed industry practice uses thermal catalysis and not electrocatalysis to create fuel, as they scale better.

“For that reason, companies probably won’t use it any time soon for large-scale production,” said Ajayan. “But electrocatalysis can be easily done in the lab, and we showed it will be useful in the development of new catalysts.” Ajayan’s team will continue their research.

The secret behind makes Graphene the strongest material in the world


Graphene the strongest material in the world so a sheet of graphene as thin as Cling film could hold the weight of an elephant

Graphene the strongest material in the world so a sheet of graphene as thin as Cling film could hold the weight of an elephant

Graphene the strongest material in the world !! and It is about 200 times stronger than steel by weight So A sheet of graphene as thin as Cling film could hold the weight of an elephant. In fact, according to one calculation, an elephant would need to balance precariously on the end of a pencil to break through that same sheet. The secret lay in graphene atomic building it an abundant mineral which is an allotrope of carbon that is made up of very tightly bonded carbon atoms organised into a hexagonal lattice very thin atomic thickness (of 0.345Nm).

The secret behind makes Graphene the strongest material in the world:

Most materials are hundreds of times strong without defects in atomic arrangements make it disrupted, Defects can dramatically weaken a material. When stressed, the material breaks at the defect – can imagine it as a chain breaks at its weakest link ( this weakest link come from defects in atomic arrangements ).
But Graphene has perfect atomic arrangements because it made by CVD ( Chemical Vapor Deposition ) it fewer defects and make it atom-scale as net of hexagonal and hexagonal one of strong shapes in nature so find bees build own home in this shape in honeycomb and shape strong in nanoscale material, Graphene gets ultimately the strength of a material comes down to the strength with which two neighbouring atoms are stuck together. The electrical attraction between carbon atoms is very strong and that is the source of strength for both graphene and diamond.

Graphene is the strongest material ever tested, with an intrinsic Tensile strength of 130 GPa and a Young’s modulus (stiffness) of 1 TPa (150000000 psi) so it expect to see it’s poised to cast a wide shadow over the future of business, graphene used as a layer in bulletproof vests, armor, aircraft skin, etc . and certainly not replacing copper flashing on roofs, cladding on cookware, etc.

Graphene a new material just one atom thick produced by nanotechnology it very strong, flexible nearly transparent and inventors of it get Noble Prize from appreciation this achievement, Graphene appearance make a revolution in materials human that known it!

Graphene is hailed as a miracle material with the potential to revolutionize products and processes across industries from consumer electronics to biomedicine.

 

Table strengths of strong materials in the world appear Graphene stronger than diamond many times (source wikipedia : Ultimate tensile strength )

Table strengths of strong materials in the world appear Graphene stronger than diamond many times (source wikipedia : Ultimate tensile strength )

 

Strongest material in the world:

In the past diamond is the most strongest material human know so when scientists put measure to test material hardness it get number from 10 degrees of diamond strength and it called ” Mohs scale of mineral hardness ” for example steel have 4 degrees and diamond have 10 the top degree in Mohs scale so human use diamond cut the strong things like rocks using saw with diamond blade because if use steel only will erosion this blades so fast and became useless, but in 2003 new material appear stronger than diamond (more 45 time stronger than diamond) and have other super features change a lot of human knowledge and because the ideal material for the future it’s Graphene !

Graphene in atomic scale looks like Diamond but structuration more organized so graphene more strong

Graphene in atomic scale looks like Diamond but structuration more organized so graphene more strong

The secret behind Graphene strength:

When looking in diamond by electron microscope find it consist of carbon atoms arranged together graphene also consist of carbon atoms only and in atomic scale looks like Diamond but it structure more organized so graphene more strong than diamond and every graphene molecule creates from six atoms arranged in look like honeycomb structure this structure make it more strong and stability .

Story of  invention Graphene :

Graphene new material and first measurably produced and isolated in the lab in 2003 , although a lot of scientists have theorized about graphene for decades before that .
Graphene invented by two Russian scientists Andre Geim and Konstantin Novoselov working in University of Manchester and won the Nobel Prize in Physics in 2010 “for groundbreaking experiments regarding the two-dimensional material graphene” , this appreciated them efforts came after many years from invent Graphene because in the first a lot of people don’t know value of Graphene and reason of that very high of cost of product Graphene in first days of invented Graphene cost of product very small piece size as human hair cost about 1000$ but after that cost of product graphene became less and less open door to make more experiments to know more about Graphene features and enter Graphene in new uses and applications.

 

 

 

 

Graphene uses :

1- Safety & Bulletproof :

Graphene bulletproof can stop bullet easily because graphene 200 times stronger than steel

Graphene bulletproof can stop bullet easily because graphene 200 times stronger than steel

Graphene the strongest material human was known so making it an ideal ingredient to armor for army and police forces, Professor Jae-Hwang Lee at the University of Massachusetts-Amherst devised a new miniature ballistics test to test graphene’s mettle. They used a laser pulse to superheat gold filaments until they vaporised, acting like gunpowder to fire a micrometre-size glass bullet into 10 to 100 sheets of graphene at 3 kilometers per second – about three times the speed of a bullet fired from an M16 rifle.

2- Planes :

Graphene plane will have super features and use less fuel

Graphene plane will have super features and use less fuel

Aero industry usually searching for strong and light materials and Graphene have this feature so a lot of future planes design depended in Graphene to give plane body more strong and graphene more good feature it transparent so some Graphene planes designed to make very wide windows and transparent wall and roof to give chance for passengers to see panoramic view of sky and get special feeling can’t test it before !
Graphene will make planes more light and less weight so make it use less fuel in sure that good from all environment ( planes make about 13% of world pollution ) and make the ticket cheaper to clients.

3- Space :

In space any crack in spaceship or space capsule can cause disaster because it makes to losing air, Oxygen and ensure that meaning deadly accident, so graphene one of best materials to space because of it strong and light weight give more advantage because it makes tool more light and strong to face very rough conditions in space.

 

Graphene will make mechanical parts more strong and stay more working

Graphene will make mechanical parts more strong and stay more working

4- Mechanical parts :

Any machine built from parts and every part have life expectancy depend on it strength and corrosion face it and when to grow it strength make life expectancy grow up also so when to use graphene to make mechanic parts have more long life and can do more tasks, Graphene also fighting corrosion by  graphene painting that paint stay than any other paints and excellent to face corrosion because of this strength .

5- Building materials :

A lot of research try to make it in many materials to give it more strong or cover it by graphene to save it from scratch or broken Graphene also fighting corrosion by ( Graphene Painting ) that paint stay than any other paints and excellent to face corrosion because of this strength.

6- Medical :

Graphene used to make biosensors because of its attractive electrical conductivity properties and its large surface to volume ratio and Graphene biosensor is better than ELISA . Graphene-based material have less permeable than other materials it very useful to infection control because all doctors suffering from permeability of medical gloves and the same problem face who use condoms because of materials ” often latex and vinyl ” permeable to water and blood  ” It can’t notice it by naked eye because it very small parts but can cause a lot of diseases ” so it can infection dangerous diseases like HIV , Bill & Melinda Gates Foundation has even donated $100,000 to the University of Manchester to help fund development of graphene-based material use in condoms and gloves have less permeable than other materials , and the first prize in the Bill and Melinda Gates Foundation condom design competition went to the Manchester-based inventors of graphene may be looked upon in the future as the beginning of it all.

7- Electronics :

Graphene flexible OLED and AMOLED display will come soon in many mobiles

Graphene flexible OLED and AMOLED display will come soon in many mobiles

Researchers and scientists find graphene the best material to replace Indium Tin Oxide (ITO) because it increasingly becomes expensive due to depletion of rare metal indium, ITO is often used to make transparent conductive coatings for displays such as liquid crystal displays, flat panel displays, plasma displays, touchscreen . and graphene have more advantages like flexibility ” ITO extremely lacks the flexibility and broken easily ” so graphene build flexible screen and many types of screen like OLED ,AMOLED, and it more bright colors and have less consumption power .

Graphene also used product future electronics parts like CPU , RAM , flash memory … etc because graphene have good feature make it competition the conventional semiconductor like silicon , and graphene the world’s thinnest material – we know graphene is a single layer of carbon atoms arranged in a honeycomb-shaped lattice in atomic scale so make it the ideal material in nanotechnology .

8- Nanotechnology :

Carbon NanoTubes (CNTs) have many used like Electronics parts ,  Biomedical , Electrical circuits , Electrical cables and wires , Actuators , Paper batteries , Solar cells and Hydrogen storage , and it usually made from graphene sheet that “roll up” make the nanotube. Graphene will replace copper in nano sutures because electrical resistance in 40-nanometer-wide nanoribbons of epitaxial graphene changes in discrete steps. The ribbons’ conductance exceeds predictions by a factor of 10. The ribbons can act more like optical waveguides or quantum dots, allowing electrons to flow smoothly along the ribbon edges. In copper, resistance increases in proportion to length as electrons encounter impurities.

9- Chemical :

Graphene has the high surface area that can be exploited especially in drugs or another chemical interactive delivery applications. Also, graphene can be surface modified with relative ease and made to bind into specific drug and can be used as drug delivery vehicles, Nano-materials graphene-based used as catalyst alternative to platinum in cell fuel  because it very expensive and have another problem platinum is very rarely material in the earth so make big scale fuel cell manufacturing impossible and make it more cheap and affordable .

Solar Panels

Solar Panels

10- Power and electricity :

A lot of efforts in to develop electronics devices batteries like mobiles , tablets , laptop ..etc to stay more , graphene material entered in new designs to make graphene battery that give more power and charging in less time , graphene enter also in solar panel design, raising its efficiency to an absolutely staggering 60% .

 

– See more at: http://www.graphene-uses.com/the-secret-behind-makes-graphene-the-strongest-material-in-the-world/?gclid=COylgubo684CFU8faAodpGMPIw#sthash.DbvyyTiy.dpuf

Graphene, the finest filter


Graphene, the finest filter

Graphene can simplify production of heavy water and help clean nuclear waste by filtering different isotopes of hydrogen, University of Manchester research indicates.

Writing in Science, a team led by Sir Andre Geim demonstrated that using membranes made from graphene can act as a sieve, separating protons – nuclei of hydrogen – from heavier nuclei of hydrogen isotope deuterium.

The process could mean producing for could be ten times less energy intensive, simpler and cheaper using graphene.

One of the hydrogen isotopes, deuterium, is widely used in analytical and chemical tracing technologies and, also, as heavy water required in thousands of tons for operation of stations.

The heaviest isotope, tritium, is radioactive and needs to be safely removed as a byproduct of electricity generation at nuclear fission plants. Future nuclear technology is based on fusion of the two heavy isotopes.

The current separation technologies for production of heavy water are extremely energy intensive, and have presented a major scientific and industrial problem. Now graphene promises do so efficiently.

Researchers tested whether deuterons – nuclei of deuterium – can pass through graphene and its sister material . They fully expected deuterons to easily pass through, as existing theory did not predict any difference in permeation for both isotopes.

The researchers were surprised to find that deuterons were not only effectively sieved out by their one atom thick membranes, but were sieved with a high separation efficiency.

The discovery makes monolayers of graphene and boron nitride attractive as separation membranes to enrich mixtures of deuterium and tritium.

Furthermore, the researchers showed that the separation is fully scalable. Using chemical-vapor-deposited (CVD) graphene, they built centimetre-sized devices to effectively pump out hydrogen from a mixture of deuterium and hydrogen.

Dr Marcelo Lozada-Hidalgo, University of Manchester postdoctoral researcher and first author of the paper, said: “This is really the first membrane shown to distinguish between subatomic particles, all at room temperature.

“Now that we showed that it is a fully scalable technology, we hope it will quickly find its way to real applications.”

Professor Irina Grigorieva, who co-authored the research, said: “We were stunned to see that a membrane can be used to separate .

“It is a really simple set up. We hope to see applications of these filters not only in analytical and chemical tracing technologies but also in helping to clean nuclear waste from radioactive tritium.”

Diamond nanothread rivals graphene as the next big wonder material


Now scientists want to build a space elevator out of it.

For some time now, graphene has been the wonder material that scientists have been most excited about using: as it develops, it promises to transform everything from night-vision goggles to energy storage. Now researchers across the globe think they’ve come up with a material to rival it: diamond nanothread.

The clues are in the name. This potentially revolutionary, next-generation material is partly made from diamond and is incredibly thin as well as incredibly strong. Technically speaking, we’re looking at a type of carbon (like graphene) taking the form of a one-dimensional diamond crystal that’s topped with hydrogen. To create the material, benzene molecules were stacked together and pressurised.

It’s too early to say how diamond nanothread could be used – right now scientists are still at the research and simulation stage – but one of the appeals of a material like this is its versatility. And a team of scientists working at the Queensland University of Technology (QUT) in Australia has been looking into the properties of diamond nanothread and think it might be more versatile and robust than originally believed.

In fact, it could be developed to be rigid in some places and flexible in others,MIT Technology Review reports. Thanks to some large-scale molecular dynamics simulations, the Australian researchers were able to create a form of diamond nanothread with built-in hinges that would allow it to fold and bend. In other words, this new super material could be made as brittle as uncooked spaghetti or as flexible as the cooked variety.

The next step is to test diamond nanothread in real-world scenarios rather than simulations.

“[The material’s] highly tunable ductility together with its ultra-light density and high Young’s modulus makes diamond nanothread ideal for creation of extremely strong three-dimensional nano-architectures,” the team writes in the paper, published online at arXiv.org. Young’s modulus refers to a material’s tendency to return to its original shape after being put under pressure.

“It is as if an incredible jeweller has strung together the smallest possible diamonds into a long miniature necklace,” Pennsylvania State University researcher John Badding said last year when the diamond nanothread material was first discovered. “Because this thread is diamond at heart, we expect that it will prove to be extraordinarily stiff, extraordinarily strong, and extraordinarily useful.”

As Gizmodo reports, the wonder material may one day be used to finally make space elevators a reality. We still need to figure out how to mass-produce this material, and test how well it’s going to stand up in various conditions, but new research is showing just how promising diamond nanothreads can be.

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