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Scientists create ultraviolet light on a graphene surface

Posted By Graphene Council, The Graphene Council, Sunday, June 2, 2019
Updated: Friday, May 31, 2019

Ultraviolet light is used to kill bacteria and viruses, but UV lamps contain toxic mercury. A newly developed nanomaterial is changing that.

The nano research team led by professors Helge Weman and Bjørn-Ove Fimland at the Norwegian University of Science and Technology (NTNU)’s Department of Electronic Systems has succeeded in creating light-emitting diodes, or LEDs, from a nanomaterial that emits ultraviolet light (Nano Letters, "GaN/AlGaN Nanocolumn Ultraviolet Light-Emitting Diode Using Double-Layer Graphene as Substrate and Transparent Electrode").It is the first time anyone has created ultraviolet light on a graphene surface.

“We’ve shown that it’s possible, which is really exciting,” says PhD candidate Ida Marie Høiaas, who has been working on the project with Andreas Liudi Mulyo, who is also a PhD candidate.
“We’ve created a new electronic component that has the potential to become a commercial product. It’s non-toxic and could turn out to be cheaper, and more stable and durable than today’s fluorescent lamps. If we succeed in making the diodes efficient and much cheaper, it’s easy to imagine this equipment becoming commonplace in people’s homes. That would increase the market potential considerably,” Høiaas says.

Dangerous – but useful

Although it’s important to protect ourselves from too much exposure to the sun’s UV radiation, ultraviolet light also has very useful properties. This applies especially to UV light with short wavelengths of 100-280 nanometres, called UVC light, which is especially useful for its ability to destroy bacteria and viruses. Fortunately, the dangerous UVC rays from the sun are trapped by the ozone layer and oxygen and don’t reach the Earth. But it is possible to create UVC light, which can be used to clean surfaces and hospital equipment, or to purify water and air.

The problem today is that many UVC lamps contain mercury. The UN’s Minamata Convention, which went into effect in 2017, sets out measures to phase out mercury mining and reduce mercury use. The convention was named for a Japanese fishing village where the population was poisoned by mercury emissions from a factory in the 1950s.

Building on graphene

A layer of graphene placed on glass forms the substrate for the researchers’ new diode that generates UV light.

Graphene is a super-strong and ultra-thin crystalline material consisting of a single layer of carbon atoms. Researchers have succeeded in growing nanowires of aluminium gallium nitride (AlGaN) on the graphene lattice.

The process takes place in a high temperature vacuum chamber where aluminium and gallium atoms are deposited or grown directly on the graphene substrate – with high precision and in the presence of nitrogen plasma. This process is known as molecular beam epitaxy (MBE) and is conducted in Japan, where the NTNU research team collaborates with Professor Katsumi Kishino at Sophia University in Tokyo.

Let there be light

After growing the sample, it is transported to the NTNU NanoLab where the researchers make metal contacts of gold and nickel on the graphene and nanowires. When power is sent from the graphene and through the nanowires, they emit UV light. Graphene is transparent to light of all wavelengths, and the light emitted from the nanowires shines through the graphene and glass.

“It’s exciting to be able to combine nanomaterials this way and create functioning LEDs, says Høiaas.
An analysis has calculated that the market for UVC products will increase by NOK 6 billion, or roughly US $700 million between now and 2023. The growing demand for such products and the phase- out of mercury are expected to yield an annual market increase of almost 40 per cent.

Concurrently with her PhD research at NTNU, Høiaas is working with the same technology on an industrial platform for CrayoNano. The company is a spinoff of NTNU’s nano research environment.

Use less electricity more cheaply

UVC LEDs that can replace fluorescent bulbs are already on the market, but CrayoNano’s goal is to create far more energy-efficient and cheaper diodes. According to the company, one reason that today’s UV LEDs are expensive is that the substrate is made of costly aluminium nitride. Graphene is cheaper to manufacture and requires less material for the LED diode.
Høiaas believes that the technology needs to be improved quite a bit before the process developed at NTNU can be scaled up to industrial production level.

Among the issues that need to be addressed are conductivity and energy efficiency, more advanced nanowire structures and shorter wavelengths to create UVC light. CrayoNano has made progress, but results documenting their progress have not yet been published. “CrayoNano’s goal is to commercialize the technology sometime in 2022,” says Høiaas.

Tags:  Bjørn-Ove Fimland  CrayoNano AS  Graphene  Helge Weman  nanomaterials  Norwegian University of Science and Technology  ultraviolet 

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AGM signs distribution agreement with CAME srl

Posted By Graphene Council, The Graphene Council, Friday, May 31, 2019

Applied Graphene Materials (AGM) announced it has signed a distribution agreement with CAME Srl, Italy, a leading international chemical distribution business. The agreement extends AGM's commercial reach directly into the Italian coatings and chemicals sectors. CAME, based in Milan, also represents a wide range of international supply partners throughout Europe and the Middle East. Its customer base includes many organisations in the coatings, adhesives and lubricants markets, making it an ideal distribution partner for AGM in the Italian market within its key target sectors.

AGM and CAME have been engaged in early market development over the last 18 months and the agreement represents a major commitment from both companies to exploit AGM's exciting graphene technology.

Adrian Potts, AGM CEO commented:

"It is an absolute priority for AGM to maximise its global exploitation plans. We are pleased with growing industry recognition of the benefits of our Genable® graphene dispersion technologies. These are proving to be ideally suited to anti-corrosion and barrier performance in coatings and are generating increasing commercial traction in the sector. We are gaining significant momentum in Italy with a growing number of target accounts. Complementary to this is our strategy of establishing a highly credible and technically reactive distribution network to effectively broaden our sales footprint. CAME are ideal partners for AGM and having worked with them over recent months, we are confident they will provide an excellent route to market for AGM products."

Verena Cepparulo, CAME Managing Director:

"We have followed the development of AGM's Genable® dispersion technology and see its great potential, particularly in the area of anti-corrosion performance. AGM has demonstrated they now have a strong product base, supported by a highly experienced and skilled technical support team, and we are very excited by the opportunity to be part of their ambitious growth plans. We have already undertaken our own market research and see significant potential within the Italian market".

Tags:  Adrian Potts  Applied Graphene Materials  CAME srl  coatings  Corrosion  Graphene  Verena Cepparulo 

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How to enlarge 2D materials as single crystals?

Posted By Graphene Council, The Graphene Council, Friday, May 31, 2019

What makes something a crystal? When all of its atoms are arranged in accordance with specific mathematical rules, we call the material a single crystal. Like the natural world has its unique symmetry just as snowflakes or honeycombs, the atomic world of crystals is designed by its own structure and symmetry. This material structure has a profound effect on its physical properties as well. Specifically, single crystals play an important role in inducing material's intrinsic properties to its full extent. Faced with the coming end of the miniaturization process that the silicon-based integrated circuit has allowed up to this point, huge efforts have been dedicated to find a single crystalline replacement for silicon.


In search for the transistor of the future, two-dimensional (2D) materials, especially graphene have been the subject of intense research around the world. Being thin and flexible as a result of being only a single layer of atoms, this 2D version of carbon even features unprecedented electricity and heat conductivity. However, the last decade's efforts for graphene transistors have been held up by physical restraints graphene allows no control over electricity flow due to the lack of band gap. Then, what about other 2D materials? A number of interesting 2D materials have been reported to have similar or even superior properties. Still, the lack of understanding in creating ideal experimental conditions for large-area 2D materials has limited their maximum size to just a few mm 2.

Scientists at the Center for Multidimensional Carbon Material (CMCM) within the Institute for Basic Science (IBS) (located in the Ulsan National Institute of Science and Technology (UNIST)) have presented a novel approach to synthesize large-scale of silicon wafer size, single crystalline 2D materials. Prof. Feng Ding and Ms. Leining Zhang in collaboration with their colleagues in Peking University, China and other institutes have found a substrate with a lower order of symmetry than that of a 2D material that facilitates the synthesis of single crystalline 2D materials in a large area. "It was critical to find the right balance of rotational symmetries between a substrate and a 2D material," notes Prof. Feng Ding, one of corresponding authors of this study. The researchers successfully synthesized hBN single crystals of 10*10 cm2 by using a new substrate: a surface nearby Cu (110) that has a lower symmetry of (1) than hBN with (3).

Then, why does symmetry matters? Symmetry, in particular rotational symmetry, describes how many times a certain shape fits on to itself during a full rotation of 360 degrees. The most efficient method to synthesize large-area and single crystals of 2D materials is to arrange layers over layers of small single crystals and grow them upon a substrate. In this epitaxial growth, it is quite challenging to ensure all of the single crystals are aligned in a single direction. Orientation of the crystals is often affected by the underlying substrate. By theoretical analysis, the IBS scientists found that an hBN island (or a group of hBN atoms forming a single triangle shape) has two equivalent alignments on the Cu(111) surface that has a very high symmetry of (6). "It was a common view that a substrate with high symmetry may lead to the growth of materials with a high symmetry. It seemed to make sense intuitively, but this study found it is incorrect," says Ms. Leining Zhang, the first author of the study.

Previously, various substrates such as Cu(111) have been used to synthesize single crystalline hBN in a large area, but none of them were successful. Every effort ended with hBN islands aligning along in several different directions on the surfaces. Convinced by the fact that the key to achieve unidirectional alignment is to reduce the symmetry of the substrate, the researchers made tremendous efforts to obtain vicinal surfaces of a Cu(110) orientation; a surface obtained by cutting a Cu(110) with a small tilt angle. It is like forming physical steps on Cu. As a hBN island tends to place in parallel to the edge of each step, it gets only one preferred alignment. The small tilt angle lowers the symmetry of the surface as well.

They eventually found that a class of vicinal surfaces of Cu (110) can be used to support the growth of hBN with perfect alignment. On a carefully selected substrate with the lowest symmetry or the surface will repeat itself only after a 360degree rotation, hBN has only one preferred direction of alignment. The research team of Prof. Kaihui Liu in Peking University, has developed a unique method to anneal a large Cu foil, up to 10*10 cm2, into a single crystal with the vicinal Cu (110) surface and, with it, they have achieved the synthesis of hBN single crystals of same size.

Besides flexibility and ultrathin thickness, emerging 2D materials can present extraordinary properties when they get enlarged as single crystals. "This study provides a general guideline for the experimental synthesis of various 2D materials. Besides the hBN, many other 2D materials could be synthesized with the large area single crystalline substrates with low symmetry," says Prof. Feng Ding. Notably, hBN is the most representative 2D insulator, which is different from the conductive 2D materials, such as graphene, and 2D semiconductors, such as molybdenum disulfide (MoS2). The vertical stacking of various types of 2D materials, such as hBN, graphene and MoS2, would lead to a large number of new materials with exceptional properties and can be used for numerous applications, such as high-performance electronics, sensors, or wearable electronics."

Tags:  2D materials  Center for Multidimensional Carbon Material  Feng Ding  Graphene  Kaihui Liu  Peking University  Semiconductors 

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Manipulating atoms one at a time with an electron beam

Posted By Graphene Council, The Graphene Council, Thursday, May 30, 2019
Updated: Friday, May 24, 2019

The ultimate degree of control for engineering would be the ability to create and manipulate materials at the most basic level, fabricating devices atom by atom with precise control.

Now, scientists at MIT, the University of Vienna, and several other institutions have taken a step in that direction, developing a method that can reposition atoms with a highly focused electron beam and control their exact location and bonding orientation. The finding could ultimately lead to new ways of making quantum computing devices or sensors, and usher in a new age of “atomic engineering,” they say.

The advance is described in the journal Science Advances, in a paper by MIT professor of nuclear science and engineering Ju Li, graduate student Cong Su, Professor Toma Susi of the University of Vienna, and 13 others at MIT, the University of Vienna, Oak Ridge National Laboratory, and in China, Ecuador, and Denmark.

“We’re using a lot of the tools of nanotechnology,” explains Li, who holds a joint appointment in materials science and engineering. But in the new research, those tools are being used to control processes that are yet an order of magnitude smaller. “The goal is to control one to a few hundred atoms, to control their positions, control their charge state, and control their electronic and nuclear spin states,” he says.

While others have previously manipulated the positions of individual atoms, even creating a neat circle of atoms on a surface, that process involved picking up individual atoms on the needle-like tip of a scanning tunneling microscope and then dropping them in position, a relatively slow mechanical process. The new process manipulates atoms using a relativistic electron beam in a scanning transmission electron microscope (STEM), so it can be fully electronically controlled by magnetic lenses and requires no mechanical moving parts. That makes the process potentially much faster, and thus could lead to practical applications.

Using electronic controls and artificial intelligence, “we think we can eventually manipulate atoms at microsecond timescales,” Li says. “That’s many orders of magnitude faster than we can manipulate them now with mechanical probes. Also, it should be possible to have many electron beams working simultaneously on the same piece of material.”

“This is an exciting new paradigm for atom manipulation,” Susi says.

Computer chips are typically made by “doping” a silicon crystal with other atoms needed to confer specific electrical properties, thus creating “defects’ in the material — regions that do not preserve the perfectly orderly crystalline structure of the silicon. But that process is scattershot, Li explains, so there’s no way of controlling with atomic precision where those dopant atoms go. The new system allows for exact positioning, he says.

The same electron beam can be used for knocking an atom both out of one position and into another, and then “reading” the new position to verify that the atom ended up where it was meant to, Li says. While the positioning is essentially determined by probabilities and is not 100 percent accurate, the ability to determine the actual position makes it possible to select out only those that ended up in the right configuration.

Atomic soccer

The power of the very narrowly focused electron beam, about as wide as an atom, knocks an atom out of its position, and by selecting the exact angle of the beam, the researchers can determine where it is most likely to end up. “We want to use the beam to knock out atoms and essentially to play atomic soccer,” dribbling the atoms across the graphene field to their intended “goal” position, he says.

“Like soccer, it’s not deterministic, but you can control the probabilities,” he says. “Like soccer, you’re always trying to move toward the goal.”

In the team’s experiments, they primarily used phosphorus atoms, a commonly used dopant, in a sheet of graphene, a two-dimensional sheet of carbon atoms arranged in a honeycomb pattern. The phosphorus atoms end up substituting for carbon atoms in parts of that pattern, thus altering the material’s electronic, optical, and other properties in ways that can be predicted if the positions of those atoms are known.

Ultimately, the goal is to move multiple atoms in complex ways. “We hope to use the electron beam to basically move these dopants, so we could make a pyramid, or some defect complex, where we can state precisely where each atom sits,” Li says.

This is the first time electronically distinct dopant atoms have been manipulated in graphene. “Although we’ve worked with silicon impurities before, phosphorus is both potentially more interesting for its electrical and magnetic properties, but as we’ve now discovered, also behaves in surprisingly different ways. Each element may hold new surprises and possibilities,” Susi adds.

The system requires precise control of the beam angle and energy. “Sometimes we have unwanted outcomes if we’re not careful,” he says. For example, sometimes a carbon atom that was intended to stay in position “just leaves,” and sometimes the phosphorus atom gets locked into position in the lattice, and “then no matter how we change the beam angle, we cannot affect its position. We have to find another ball.”

Theoretical framework
In addition to detailed experimental testing and observation of the effects of different angles and positions of the beams and graphene, the team also devised a theoretical basis to predict the effects, called primary knock-on space formalism, that tracks the momentum of the “soccer ball.” “We did these experiments and also gave a theoretical framework on how to control this process,” Li says.

The cascade of effects that results from the initial beam takes place over multiple time scales, Li says, which made the observations and analysis tricky to carry out. The actual initial collision of the relativistic electron (moving at about 45 percent of the speed of light) with an atom takes place on a scale of zeptoseconds — trillionths of a billionth of a second — but the resulting movement and collisions of atoms in the lattice unfolds over time scales of picoseconds or longer — billions of times longer.

Dopant atoms such as phosphorus have a nonzero nuclear spin, which is a key property needed for quantum-based devices because that spin state is easily affected by elements of its environment such as magnetic fields. So the ability to place these atoms precisely, in terms of both position and bonding, could be a key step toward developing quantum information processing or sensing devices, Li says.

“This is an important advance in the field,” says Alex Zettl, a professor of physics at the University of California at Berkeley, who was not involved in this research. “Impurity atoms and defects in a crystal lattice are at the heart of the electronics industry. As solid-state devices get smaller, down to the nanometer size scale, it becomes increasingly important to know precisely where a single impurity atom or defect is located, and what are its atomic surroundings. An extremely challenging goal is having a scalable method to controllably manipulate or place individual atoms in desired locations, as well as predicting accurately what effect that placement will have on device performance.”

Zettl says that these researchers “have made a significant advance toward this goal. They use a moderate energy focused electron beam to coax a desirable rearrangement of atoms, and observe in real-time, at the atomic scale, what they are doing. An elegant theoretical treatise, with impressive predictive power, complements the experiments.”

Besides the leading MIT team, the international collaboration included researchers from the University of Vienna, the University of Chinese Academy of Sciences, Aarhus University in Denmark, National Polytechnical School in Ecuador, Oak Ridge National Laboratory, and Sichuan University in China. The work was supported by the National Science Foundation, the U.S. Army Research Office through MIT’s Institute for Soldier Nanotechnologies, the Austrian Science Fund, the European Research Council, the Danish Council for Independent Research, the Chinese Academy of Sciences, and the U.S. Department of Energy.

Tags:  2D materials  Alex Zettl  Electronics  Graphene  Ju Li  MIT  Toma Susi  University of California at Berkeley  University of Vienna 

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Applied Graphene Materials secures patent approval

Posted By Graphene Council, The Graphene Council, Thursday, May 30, 2019
Updated: Saturday, May 25, 2019

Applied Graphene Materials announced that the Company has received patent approval for its unique manufacturing process in the tenth out of eleven territorial applications made in 2019. 

AGM’s strategy is to ensure it has patent coverage in all of the major international territories in order to protect its technology.

This latest patent approval is in a strategically important territory for the Group and follows receipt of approval from the USA patent office in 2018.

As the Company deepens its dispersion expertise to enable the effective transfer of graphene’s unique combination of properties into customer materials, AGM continues to file patent applications for its proprietary manufacturing and dispersion processes, and products as appropriate, with a particular focus on graphene dispersions for paints and coatings.

Adrian Potts, Chief Executive Officer of Applied Graphene Materials, said:
“Our aim is to become a leading supplier of graphene globally. Receiving patent approval in another strategically important territory for AGM is an important development, as we continue to secure our competitive position in international markets where we see significant long-term commercial opportunity.”

Tags:  Adrian Potts  Applied Graphene Materials  coatings  Graphene  Paint 

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Gratomic Launches its first production of graphene from Gratomic Graphite Derived Product

Posted By Graphene Council, The Graphene Council, Thursday, May 30, 2019
Updated: Saturday, May 25, 2019

Gratomic Inc. has announced its first graphene from Gratomic Graphite derived product. Gratomic graphenes derived from Gratomic graphite mined from its Aukum Mine located in Namibia are being used to manufacture Graphene enabled conductive inks and pastes. The inks and pastes (to the best of the Company's knowledge) are amongst the most conductive carbon inks and pastes currently available within the global market place.

The Gratink product is formulated specifically to meet the needs of the printed flexible electronics and EMI shielding markets. Electromagnetic interference (EMI), sometimes referred to as radio-frequency interference (RFI) is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction.

The Gratink and paste applications based on surface modified nano graphene "enablers" offer a product for market penetration into the information technology sector that is now an important aspect of our everyday life.  

The Gratomic Gratink product delivers a functional print and coat component solution.

Due to a multiple range of potential applications including antennas, RFID tags, transistors, sensors, and wearable electronics, the development of printed conductive inks and coatings for electronic applications is growing rapidly. Currently available conductive inks exploit metal nanoparticles to realize electrical conductivity.

Traditionally, metallic nanoparticles are normally derived from silver, copper and platinum based enablers which can be expensive and easily oxidized.

The Gratink product is designed to fill a gap in both the flexible printed electronics and EMI market space where metallic nanoparticle solutions are unnecessary.

Gratink is initially available to meet customer printing and coating preference specifications for R&D purposes with orders available in one-kilo packages.

Following satisfactory customer preproduction qualification, the products can then be varied so they are suitable for printing and coating in bulk quantities formulated to specification and made available as required in 10's to 100's of kilos or tonnes.

Please note - Inks and pastes are prepared for all currently available methods of printing and coating with the exception of ink jet printing.

Sheldon Inwentash Co-CEO of Gratomic commented. "Gratomic is delighted to offer their first product of a planned product range based on the Company's graphene derived from graphite mined from its Aukum Mine."

Gratink is a collaborative development product formulated in tandem with Perpetuus Carbon Technology Wales UK and Gratomic Inc.

***

Are you interested in developing graphene enhanced products or applications?

Find a suitable application partner / supplier through The Graphene Council 

Tags:  coatings  Graphene  Graphite  Gratomic  nanoparticles  Perpetuus Carbon Technologies  Sensors  Sheldon Inwentash 

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UK's National Grid Verifies Viability of Graphene Composite Application

Posted By Graphene Council, The Graphene Council, Tuesday, May 21, 2019
Updated: Monday, May 20, 2019
Haydale plc has been working with the UK's National Grid to calculate the benefit case of its Composite Transition Piece (CTP), using a method developed by National Grid and verified by PwC during a previous audit. This approach provides a risk rating for the benefits. In this case the risk was assessed by National Grid as ‘low’, meaning that National Grid can have a high level of confidence in the results it will achieve.

There are around 300 locations on the National Transmission System in the UK where gas pipes pass through reinforced concrete walls, for example into valve pits. Currently, several types of seal are used to prevent contamination by water or soil, but when these seals fail technicians face a major task to fix the problem.

National Grid has found that Haydale’s CTP represents a huge step forward in safety and efficiency, solving a major problem for the national gas transmission network at a reduced cost over the system’s life-time. The solution allows easy access to transition pipes at pit wall transitions for inspection and maintenance. Working in conjunction with National Grid, the innovative CTP seal units can be used to plug the gap between the pipe and the wall. It means that technicians can easily remove the unit and check the pipe for corrosion or damage. The CTP can then be replaced quickly in one simple operation.

Financially, the benefits of installing a CTP are significant especially when viewed over the entire design life of the unit. Taking less time to inspect the pit wall area with a CTP fitted means that just under £230k could be saved over a design life of 50 years per unit installed. This is comparing an inspection using the traditional methods with the composite solution.

In addition to the cost benefits, National Grid estimates that 700 fewer hours of ‘at risk’ activities will be needed for each CTP during its design life. Working on the pit wall requires technicians to work inside a pit which may be several meters deep. Benefits can be tracked after the first inspection and continue for the entire design life of 50 years per unit, this can subsequently be extended further following a simple replacement of the seal around the CTP.

There are also environmental benefits and National Grid have calculated that the new approach will save 12 tonnes of carbon equivalent (CO2e) for each CTP over its 50-year lifespan. This is determined by examining tasks such as excavating soil to expose the pit wall and generator power needed on site for the duration of the works

Two key compressor sites have already undergone large-scale works where National Grid have utilised the new CTPs. In total, eight new CTPs have been pre-fabricated and will be installed during the construction of the pit wall, further reducing installation costs. These units, along with one that was installed as part of the original trial, will start to provide benefits after their first inspections.

David Banks, Chairman at Haydale, commented: “With 9 CTPs planned for installation by the end of 2019, we look forward to seeing the benefits realised by National Grid. We look forward to continuing our work with the utilities industry, where the benefit of both composite materials and graphene are now being appreciated.”

Keith Broadbent, CEO at Haydale, commented: “Haydale is pleased to be working with National Grid on this system which is a huge step forward in safety and efficiency for the gas network. With £228,000 average savings per CTP design life and 700 fewer hours carrying out ‘at risk’ activities for each CTP over 50-year period, it is clear to see the benefit that the system offers to the customer.We look forward to working with gas infrastructure owners worldwide who can also benefit from
the product.”

Paul Ogden, Senior Civil Engineer at National Grid, commented: “Over a six-year period, National Grid expects to install about 60 CTPs on the National Transmission System. This will significantly improve safety as well as creating savings of up to £5 million in the next five to 10 years.”

Tags:  composites  David Banks  Graphene  Haydale  Keith Broadbent  National Grid  Paul Ogden 

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Flexible, transparent monolayer graphene device for power generation and storage

Posted By Graphene Council, The Graphene Council, Wednesday, May 15, 2019
Updated: Tuesday, May 14, 2019
Researchers at Daegu Gyeongbuk Institute of Science and Technology developed single-layer graphene based multifunctional transparent devices that are expected to be used as electronics and skin-attachable devices with power generation and self-charging capability (ACS Applied Materials & Interfaces, "Single-Layer Graphene-Based Transparent and Flexible Multifunctional Electronics for Self-Charging Power and Touch-Sensing Systems").

Senior Researcher Changsoon Choi's team actively used single-layered graphene film as electrodes in order to develop transparent devices. Due to its excellent electrical conductivity and light and thin characteristics, single-layered graphene film is perfect for electronics that require batteries.

By using high-molecule nano-mat that contains semisolid electrolyte, the research team succeeded in increasing transparency (maximum of 77.4%) to see landscape and letters clearly.

Furthermore, the research team designed structure for electronic devices to be self-charging and storing by inserting energy storage panel inside the upper layer of power devices and energy conversion panel inside the lower panel. They even succeeded in manufacturing electronics with touch-sensing systems by adding a touch sensor right below the energy storage panel of the upper layer.

Senior Researcher Changsoon Choi in the Smart Textile Research Group, the co-author of this paper, said that "We decided to start this research because we were amazed by transparent smartphones appearing in movies. While there are still long ways to go for commercialization due to high production costs, we will do our best to advance this technology further as we made this success in the transparent energy storage field that has not had any visible research performances."

Tags:  Batteries  Changsoon Choi  Daegu Gyeongbuk Institute of Science and Technolog  Graphene  nanomaterials 

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How to purify water with graphene

Posted By Graphene Council, The Graphene Council, Wednesday, May 15, 2019
Updated: Wednesday, May 1, 2019
Scientists from the National University of Science and Technology "MISIS" together with their colleagues from Derzhavin Tambov State University and Saratov Chernyshevsky State University have figured out that graphene is capable of purifying water, making it drinkable, without further chlorination. "Capturing" bacterial cells, it forms flakes that can be easily extracted from the water. Graphene separated by ultrasound can be reused. The article on the research is published in Materials Science & Engineering C.

Graphene and graphene oxide (a more stable version of the material in colloidal solutions) are carbon nanostructures that are extremely promising for Biomedicine. For example, it can be used for targeted drug delivery on graphene "scales" and for tumor imaging. Another interesting property of graphene and graphene oxide is the ability to destroy bacterial cells, even without the additional use of antibiotic drugs.

Scientists from the National University of Science and Technology "MISIS" together with their colleagues from Derzhavin Tambov State University and Saratov Chernyshevsky State University have conducted an experiment, injecting graphene oxide into solutions (nutrient medium and the saline) containing E.coli. Under the terms of the experiment, saline "simulated" water, and the nutrient medium simulated human body medium. The results showed that the graphene oxide along with the living and the destroyed bacteria form flakes inside the solutions. The resulting mass can be easily extracted, making water almost completely free of bacteria. If the extracted mass is then treated with ultrasound, graphene can be separated and reused.

"As working solutions, we chose a nutrient medium for the cultivation of bacteria (it is to the natural habitat of bacteria), as well as ordinary saline, which is used for injections. As a tested bacterial culture, E. coli modified with a luminescent agent was used to facilitate visualization of the experiments, was used", Aleksandr Gusev, one of the authors, Associate Professor of NUST MISIS Department of Functional Nanosystems and High-Temperature Materials, comments.

Graphene oxide was added to the nutrient solution in different concentrations - 0.0025 g/l, 0, 025 g/l, 0.25 g/l and 2.5 g/l. As it turned out, even at a minimum concentration of graphene oxide in saline (water), the observed antibacterial effect was significantly higher than in the nutrient medium (human body). Scientists believe that this indicates not a mechanical, but a biochemical nature of the mechanism of action, that is, since there are far fewer nutrients in the saline solution, the bacteria moved more actively and was "captured" by the scales of graphene oxide more often.

According to the fluorescent test data, confirmed by laser confocal microscopy and scanning electron microscopy, at 2.5 g/l concentration of graphene oxide, the number of bacteria decreased several times compared to the control group and became close to zero.

While it is not yet known exactly how the further destruction of bacteria occurs, researchers believe that graphene oxide provokes the formation of free radicals that are harmful to bacteria.

According to scientists, if such a purification system is used for water, it will be possible to avoid additional chlorination. There are other advantages: decontamination with graphene oxide has a low cost, in addition, this technology is easy to scale to the format of large urban wastewater treatment plants.

Tags:  Aleksandr Gusev  Derzhavin Tambov State University  Graphene  National University of Science and Technology  Saratov Chernyshevsky State University  water purification 

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Gratomic Announces Signing of a Definitive Graphite Concentrate Sales Agreement and Exclusive Marketing Agent for Continental Europe

Posted By Graphene Council, The Graphene Council, Tuesday, May 14, 2019

Gratomic announces the entering into of a definitive off take agreement for graphite concentrate to be produced from its Aukam Graphite mine in Namibia.

As part of the Graphite Concentrate sales Agreement (Sales Agreement), Gratomic has appointed Phu Sumika ("PSK") as its exclusive marketing agent, in continental Europe, for the sale of graphite concentrate to the refractory, lubricant and battery Markets.

Pursuant to the Sales Agreement, PSK will purchase up to 7,500 Dry Metric Tonnes annually, for a period of five years from the date commercial production commences at Aukam. The contract contemplates the sales of graphitic product ranging from 80% Carbon to 99.9% Carbon at prices ranging between US$500-US$2800 per Metric Tonne (depending on grade, moisture content and industry use).

Gratomic is satisfied with the high value range of product pricing for the selected markets. Gratomic has delivered PSK with samples grading 92%, 97%, 99% and 99.9% over the past 3 months for testing in a verity of end uses. The results now positively match buyer specifications and will qualify the sales agreement for deliveries going forward.

Aukam Production Update

Gratomic has recently consulted with a processing expert in Toronto and has been able to produce several batches of Battery Grade Graphite grading over 99.9% the Company is currently compiling a budget to integrate the suggestive plant adjustment onto its processing circuit within the next 3 months. This will allow the company to commence with the production and sale of battery grade Graphite targeted towards the rapidly growing battery industry mainly being dominated by the increase of demand for electric vehicles worldwide.

In addition Gratomic expects the delivery of the final components of its Aukam processing plant within the next 49 days, this will complete the construction of the first phase of our Processing facility and bring it up to a 3 metric tonne per hour Processing Capacity.

The company continues its focus on further developing and commercializing its Graphene Processing capacity in wales through its partnership with Perpetuus carbon technologies and anticipates soft launching its Gratomic fuel efficient tire in the summer. Gratomic has recently prepared an additional 2 tonnes of Graphite concentrate which it will be shipping to wales in the coming days for converting into high quality Graphenes targeted for the use and development of several high value Graphene applications.

Gratomic's CO-CEO Arno Brand stated, "The entering into of the sales agreement and exclusive marketing agreement with Phu Sumika is the culmination of several years of work, Gratomic is now well positioned and ready to monetize its operations through graphite sales. We thank our loyal shareholders for their support throughout  the years and their contributions in helping us in commercialize the Aukam Mine"

Tags:  Arno Brand  Battery  Graphene  Graphite  Gratomic 

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