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A new 'periodic table' for nanomaterials

Posted By Graphene Council, The Graphene Council, Monday, February 18, 2019

The approach was developed by Daniel Packwood of Kyoto University's Institute for Integrated Cell-Material Sciences (iCeMS) and Taro Hitosugi of the Tokyo Institute of Technology. It involves connecting the chemical properties of molecules with the nanostructures that form as a result of their interaction. A machine learning technique generates data that is then used to develop a diagram that categorizes different molecules according to the nano-sized shapes they form. This approach could help materials scientists identify the appropriate molecules to use in order to synthesize target nanomaterials.

Fabricating nanomaterials using a bottom-up approach requires finding 'precursor molecules' that interact and align correctly with each other as they self-assemble. But it's been a major challenge knowing how precursor molecules will interact and what shapes they will form.

Bottom-up fabrication of graphene nanoribbons is receiving much attention due to their potential use in electronics, tissue engineering, construction, and bio-imaging. One way to synthesise them is by using bianthracene precursor molecules that have bromine 'functional' groups attached to them. The bromine groups interact with a copper substrate to form nano-sized chains. When these chains are heated, they turn into graphene nanoribbons.

Packwood and Hitosugi tested their simulator using this method for building graphene nanoribbons.

Data was input into the model about the chemical properties of a variety of molecules that can be attached to bianthracene to 'functionalize' it and facilitate its interaction with copper. The data went through a series of processes that ultimately led to the formation of a 'dendrogram'.

This showed that attaching hydrogen molecules to bianthracene led to the development of strong one-dimensional nano-chains. Fluorine, bromine, chlorine, amidogen, and vinyl functional groups led to the formation of moderately strong nano-chains. Trifluoromethyl and methyl functional groups led to the formation of weak one-dimensional islands of molecules, and hydroxide and aldehyde groups led to the formation of strong two-dimensional tile-shaped islands.

The information produced in the dendogram changed based on the temperature data provided. The above categories apply when the interactions are conducted at -73°C. The results changed with warmer temperatures. The researchers recommend applying the data at low temperatures where the effect of the functional groups' chemical properties on nano-shapes are most clear.

The technique can be applied to other substrates and precursor molecules. The researchers describe their method as analogous to the periodic table of chemical elements, which groups atoms based on how they bond to each other. "However, in order to truly prove that the dendrograms or other informatics-based approaches can be as valuable to materials science as the periodic table, we must incorporate them in a real bottom-up nanomaterial fabrication experiment," the researchers conclude in their study. "We are currently pursuing this direction in our laboratories."

Tags:  Daniel Packwood  Graphene  Graphene Nanoribbons  Kyoto University  nanomaterials  Taro Hitosugi  Tokyo Institute of Technology 

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Laser-induced graphene gets tough

Posted By Graphene Council, The Graphene Council, Monday, February 18, 2019
Updated: Monday, February 18, 2019
Laser-induced graphene (LIG), a flaky foam of the atom-thick carbon, has many interesting properties on its own but gains new powers as part of a composite.

The labs of Rice University chemist James Tour and Christopher Arnusch, a professor at Ben-Gurion University of the Negev in Israel, introduced a batch of LIG composites in the American Chemical Society journal ACS Nano that put the material’s capabilities into more robust packages.

By infusing LIG with plastic, rubber, cement, wax or other materials, the lab made composites with a wide range of possible applications. These new composites could be used in wearable electronics, in heat therapy, in water treatment, in anti-icing and deicing work, in creating antimicrobial surfaces and even in making resistive random-access memory devices.

The Tour lab first made LIG in 2014 when it used a commercial laser to burn the surface of a thin sheet of common plastic, polyimide. The laser’s heat turned a sliver of the material into flakes of interconnected graphene. The one-step process made much more of the material, and at far less expense, than through traditional chemical vapor deposition.

Since then, the Rice lab and others have expanded their investigation of LIG. Last year, the Rice researchers created graphene foam for sculpting 3D objects.

“LIG is a great material, but it’s not mechanically robust,” said Tour, who co-authored an overview of laser-induced graphene developments in the Accounts of Chemical Research journal last year. “You can bend it and flex it, but you can’t rub your hand across it. It’ll shear off. If you do what’s called a Scotch tape test on it, lots of it gets removed. But when you put it into a composite structure, it really toughens up.”

To make the composites, the researchers poured or hot-pressed a thin layer of the second material over LIG attached to polyimide. When the liquid hardened, they pulled the polyimide away from the back for reuse, leaving the embedded, connected graphene flakes behind.

Soft composites can be used for active electronics in flexible clothing, Tour said, while harder composites make excellent superhydrophobic (water-avoiding) materials. When a voltage is applied, the 20-micron-thick layer of LIG kills bacteria on the surface, making toughened versions of the material suitable for antibacterial applications.

Composites made with liquid additives are best at preserving LIG flakes’ connectivity. In the lab, they heated quickly and reliably when voltage was applied. That should give the material potential use as a deicing or anti-icing coating, as a flexible heating pad for treating injuries or in garments that heat up on demand.

“You just pour it in, and now you transfer all the beautiful aspects of LIG into a material that’s highly robust,” Tour said.

Rice graduate students Duy Xuan Luong and Kaichun Yang and former postdoctoral researcher Jongwon Yoon, now a senior researcher at the Korea Basic Science Institute, are co-lead authors of the paper. Co-authors are former Rice postdoctoral researcher Swatantra Singh, now at the Indian Institute of Technology Bombay, and Rice graduate student Tuo Wang. Tour is the T.T. and W.F. Chao Chair in Chemistry as well as a professor of computer science and of materials science and nanoengineering at Rice.

The Air Force Office of Scientific Research and the United States-Israel Binational Science Foundation supported the research.

Tags:  Christopher Arnusch  Graphene  James Tour  Lasers  Rice University 

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Waterproof graphene electronic circuits

Posted By Graphene Council, The Graphene Council, Thursday, February 14, 2019
Updated: Thursday, February 14, 2019
Water molecules distort the electrical resistance of graphene, but a team of European researchers has discovered that when this two-dimensional material is integrated with the metal of a circuit, contact resistance is not impaired by humidity. This finding will help to develop new sensors –the interface between circuits and the real world– with a significant cost reduction.

The many applications of graphene, an atomically-thin sheet of carbon atoms with extraordinary conductivity and mechanical properties, include the manufacture of sensors. These transform environmental parameters into electrical signals that can be processed and measured with a computer.

Due to their two-dimensional structure, graphene-based sensors are extremely sensitive and promise good performance at low manufacturing cost in the next years.
To achieve this, graphene needs to make efficient electrical contacts when integrated with a conventional electronic circuit. Such proper contacts are crucial in any sensor and significantly affect its performance.

But a problem arises: graphene is sensitive to humidity, to the water molecules in the surrounding air that are adsorbed onto its surface. H2O molecules change the electrical resistance of this carbon material, which introduces a false signal into the sensor.

However, Swedish scientists have found that when graphene binds to the metal of electronic circuits, the contact resistance (the part of a material's total resistance due to imperfect contact at the interface) is not affected by moisture.

“This will make life easier for sensor designers, since they won't have to worry about humidity influencing the contacts, just the influence on the graphene itself,” explains Arne Quellmalz, a PhD student at KTH Royal Institute of Technology (Sweden) and the main researcher of the research.

The study, published in the journal ACS Applied Materials & Interfaces, has been carried out experimentally using graphene together with gold metallization and silica substrates in transmission line model test structures, as well as computer simulations.

“By combining graphene with conventional electronics, you can take advantage of both the unique properties of graphene and the low cost of conventional integrated circuits.” says Quellmalz, “One way of combining these two technologies is to place the graphene on top of finished electronics, rather than depositing the metal on top the graphene sheet.”

As part of the European CO2-DETECT project, the authors are applying this new approach to create the first prototypes of graphene-based sensors. More specifically, the purpose is to measure carbon dioxide (CO2), the main greenhouse gas, by means of optical detection of mid-infrared light and at lower costs than with other technologies.

Tags:  2D materials  Arne Quellmalz  Electronics  Graphene  KTH Royal Institute of Technology 

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Scientists Probe into the Effect of Graphene on Light-wave Interaction

Posted By Graphene Council, The Graphene Council, Wednesday, February 13, 2019
Updated: Wednesday, February 13, 2019
Two-dimensional (2D) nanomaterials are helping facilitate nanostructure science. Their outstanding nonlinear optical properties like enhanced two-photon absorption and absorption saturation make new applications possible in laser technologies, optical computing and telecommunications. 

Nowadays, ongoing wave mixing studies in 2D materials mainly focus on harmonic generation. Four-wave mixing in near infrared was recently carried out on a graphene monolayer, and revealed a third-order nonlinear susceptibility χ(3) value, which is about 7 orders of magnitude larger than in bulk insulators like silica and BK7 glass, 3-5 orders larger than in bulk semiconductors like silicon, germanium, cadmium and zinc chalcogenides, metal oxides, and 10 times larger than in thin plasmonic gold films and nanoparticles.

Most recently, an even larger value was obtained in graphene nanoribbons at mid-infrared frequencies close to the transverse plasmon resonance. 

Despite these not yet abundant but impressive advances of phase conjugation in graphene, the effect of 2D materials on Stimulated Brillouin scattering (SBS) remains overlooked. Due to its fundamental importance in laser and fiber telecommunications, the effect currently attracts theoretical considerations concerning bulk and composite semiconductor materials, including practical designs. 

Recently, a collaborative study led by Prof. Dr. WANG Jun at Laboratory of Micro-Nano Optoelectronic Materials and Devices, Key Laboratory of Materials for High-Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, investigated the character of SBS of low-concentration graphene nanoparticle suspensions in N-methyl-2-pyrrolidone (NMP) and water. 

They found a strong SBS quenching effect which was attributed to the interference of density gratings formed in the liquid by electrostriction and thermal expansion forces (see Fig. 1).

Established linear dependences of SBS threshold on graphene absorption coefficient (i.e., concentration) can be used for the detection of small nanomaterial quantities in liquid media down to 5×10-8g·cm-3. 

Computer simulations of the Brillouin gain factor show the efficiency of different thermodynamic, electrooptic and photoacoustic parameters in the SBS quenching. The role of density and compressibility, which change as a result of carbon vapor bubble formation, is found to be decisive in leading to dramatic changes of refractive index, electrostrictive and acoustic damping coefficients. 

The effect can give tools to bubble nanosecond dynamics studies and a method of SBS suppression in optical composites applicable in laser technologies and optical telecommunication networks. 

This study, entitled "Stimulated Brillouin scattering in dispersed graphene" has been published online in Optics Express on Dec. 18, 2018. 

This work was supported by the Chinese National Natural Science Foundation, the Strategic Priority Research Program of CAS, the Key Research Program of Frontier Science of CAS, the Program of Shanghai Academic Research Leader and President’s International Fellowship Initiative of CAS.  

Tags:  2D materials  Graphene 

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Haydale in Collaborative SMART Expertise Programme on Applications of Functionalised Micro & Nano Materials

Posted By Graphene Council, The Graphene Council, Tuesday, February 12, 2019

Haydale is pleased to announce that it is working alongside Swansea University, GTS Flexibles, Alliance Labels, Tectonic International, ScreenTec, Alliance Labels, Malvern Panalytical and the English Institute of Sport on a Welsh Government SMART Expertise Program. The programme, funded by the Welsh Government as part of its European Development Fund, is intended to benefit industry in Wales through the development of new concepts and advanced functionalised inks using Haydale’s advanced materials.

Combining expertise from across the consortium, the programme will see the creation of a product pipeline for the scale up to volume production of Applications of Functionalised Micro & Nano Materials, also known as the AFM2 Product Pipeline. This is designed to speed up the process required to take products from proof of concept into volume and profitable products. With a focus on market pull, the AFM2 Product Pipeline will turn a demand driven idea into a bench prototype followed by pilot production for market and customer evaluation.

The first examples to shape this pipeline development will be provided by the English Institute of Sport (EIS), Tectonic and GTS Flexibles, with an intention to generate a steady feed of new concepts into the pipeline to ensure its sustainability beyond the project.
 
As previously announced, Haydale, in collaboration with WCPC, has developed and refined a range of proprietary printing inks utilising its functionalised graphene for the development of advanced wearable technology to be embedded into a range of apparel for elite athletes in training for the 2020 Olympic and Paralympic Games. The functionalised inks fulfil a range of functions in sensing and conditioning, combined with ease of printing for use in the rapidly growing wearable technology market. 
 
Professor Tim Claypole MBE, Director, the Welsh Centre for Printing and Coating, Swansea University, said: “This is a really exciting project which will take innovative concepts manufactured by printing of advanced functional materials and rapidly transitioned them from proof of concept into volume, profitable products. It will drive more applications for inks containing the unique functionalised nano carbons created by the Haydale Plasma Functionalisation process.”
 
Keith Broadbent, Haydale COO, said: “The close relationship with our colleagues at WCPC is now bearing fruit with a range of robust, stable, high performing functionalised inks and coatings emerging from extensive development work and finding applications in wearable technology, printed sensors and thermal management.”

Tags:  Alliance Labels  Graphene  GTS Flexibles  Haydale  Malvern Panalytical  ScreenTec  Swansea University  Tectonic International 

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Coating for metals rapidly heals over scratches and scrapes to prevent corrosion

Posted By Graphene Council, The Graphene Council, Wednesday, February 6, 2019
Updated: Wednesday, February 6, 2019
It’s hard to believe that a tiny crack could take down a gigantic metal structure. But sometimes bridges collapse, pipelines rupture and fuselages detach from airplanes due to hard-to-detect corrosion in tiny cracks, scratches and dents.

A Northwestern University team has developed a new coating strategy for metal that self-heals within seconds when scratched, scraped or cracked. The novel material could prevent these tiny defects from turning into localized corrosion, which can cause major structures to fail.

“Localized corrosion is extremely dangerous,” said Jiaxing Huang, who led the research. “It is hard to prevent, hard to predict and hard to detect, but it can lead to catastrophic failure.” 

When damaged by scratches and cracks, Huang’s patent-pending system readily flows and reconnects to rapidly heal right before the eyes. The researchers demonstrated that the material can heal repeatedly — even after scratching the exact same spot nearly 200 times in a row.

The study was published today (Jan. 28) in Research, the first Science Partner Journal recently launched by the American Association for the Advancement of Science (AAAS) in collaboration with the China Association for Science and Technology (CAST). Huang is a professor of materials science and engineering in Northwestern’s McCormick School of Engineering.

While a few self-healing coatings already exist, those systems typically work for nanometer- to micron-sized damages. To develop a coating that can heal larger scratches in the millimeter-scale, Huang and his team looked to fluid. 

“When a boat cuts through water, the water goes right back together,” Huang said. “The ‘cut’ quickly heals because water flows readily. We were inspired to realize that fluids, such as oils, are the ultimate self-healing system.”

But common oils flows too readily, Huang noted. So he and his team needed to develop a system with contradicting properties: fluidic enough to flow automatically but not so fluidic that it drips off the metal’s surface. 

The team met the challenge by creating a network of lightweight particles — in this case graphene capsules — to thicken the oil. The network fixes the oil coating, keeping it from dripping. But when the network is damaged by a crack or scratch, it releases the oil to flow readily and reconnect. Huang said the material can be made with any hollow, lightweight particle — not just graphene.

“The particles essentially immobilize the oil film,” Huang said. “So it stays in place.”

The coating not only sticks, but it sticks well — even underwater and in harsh chemical environments, such as acid baths. Huang imagines that it could be painted onto bridges and boats that are naturally submerged underwater as well as metal structures near leaked or spilled highly corrosive fluids. The coating can also withstand strong turbulence and stick to sharp corners without budging. When brushed onto a surface from underwater, the coating goes on evenly without trapping tiny bubbles of air or moisture that often lead to pin holes and corrosion. 

“Self-healing microcapsule-thickened oil barrier coatings” was supported by the Office of Naval Research (ONR N000141612838). Graduate student Alane Lim and Chenlong Cui, a former member of Huang’s research group, served as the paper’s co-first authors.

Tags:  Graphene  Jiaxing Huang  Northwestern University 

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Large, stable pieces of graphene produced with unique edge pattern

Posted By Graphene Council, The Graphene Council, Wednesday, February 6, 2019
Updated: Wednesday, February 6, 2019

Graphene is a promising material for use in nanoelectronics. Its electronic properties depend greatly, however, on how the edges of the carbon layer are formed. Zigzag patterns are particularly interesting in this respect, but until now it has been virtually impossible to create edges with a pattern like this. Chemists and physicists at FAU have now succeeded in producing stable nanographene with a zigzag edge.

Not only that, the method they used was even comparatively simple. Their research, conducted within the framework of collaborative research centre 953  – Synthetic Carbon Allotropes funded by the German Research Foundation (DFG), has now been published in the journal Nature Communications*.

Bay, fjord, cove, armchair and zigzag – when chemists use terms such as these, it is clear that they are referring to nanographene. More specifically, the shape taken by the edges of nanographene, i.e. small fragments of graphene. Graphene consists of a single-layered carbon structure, where each carbon atom is surrounded by three others. This creates a pattern reminiscent of a honeycomb, with atoms in each of the corners. Nanographene is a promising candidate for use in the field of microelectronics, taking over from silicon which is used today and bringing microelectronics down to the nano scale.

The electronic properties of the material depend greatly on its shape, size and above all, periphery, in other words how the edges are structured. A zigzag periphery is particularly suitable, as in this case the electrons, which act as charge carriers, are more mobile than in other edge structures. This means that using pieces of zigzag-shaped graphene in nanoelectronic components may allow higher frequencies for switches.

The problem currently faced by materials scientists who want to research only zigzag nanographene is that this form makes the compounds rather unstable, and unable to be produced in a controlled manner. This is a prerequisite, however, if the electronic properties are to be investigated in detail.

The team of researchers led by PD Dr. Konstantin Amsharov from the Chair of Organic Chemistry II have now succeeded in doing just that. Not only have they discovered a straightforward method for synthesising zigzag nanographene, their procedure delivers a yield of close to one hundred percent and is suitable for large scale production. They have already produced a technically relevant quantity in the laboratory.

First of all, the FAU researchers produce preliminary molecules, which they then fitt together in a honeycomb formation over several cycles, in a process known as cyclisation. In the end, graphene fragments are produced from staggered rows of honeycombs or four-limbed stars surrounding a central point of four graphene honeycombs, with the sought-after zigzag pattern to their edges. Why is this method able to produce stable zigzag nanographene? The explanation lies in the fact that the product crystallises directly even during synthesis. In their solid state, the molecules are not in contact with oxygen. In solution, however, oxidation causes the structures to disintegrate quickly.

This approach allows scientists to produce large pieces of graphene, whilst maintaining control over their shape and periphery. This breakthrough in graphene research means that scientists should soon be able to produce and research a variety of interesting nanographene structures, a crucial step towards finally being able to use the material in nanoelectronic components.

Tags:  Friedrich–Alexander University  Graphene  Konstantin Amsharov  nanoelectronics  nanographene 

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Engineers develop novel strategy for designing semiconductor nanoparticles for wide-ranging applications

Posted By Graphene Council, The Graphene Council, Tuesday, February 5, 2019
Updated: Tuesday, February 5, 2019
Two-dimensional (2D) transition metal dichalcogenides (TMDs) nanomaterials such as molybdenite (MoS2), which possess a similar structure as graphene, have been donned the materials of the future for their wide range of potential applications in biomedicine, sensors, catalysts, photodetectors and energy storage devices.

The smaller counterpart of 2D TMDs, also known as TMD quantum dots (QDs) further accentuate the optical and electronic properties of TMDs, and are highly exploitable for catalytic and biomedical applications. However, TMD QDs is hardly used in applications as the synthesis of TMD QDs remains challenging.

Now, engineers from the National University of Singapore (NUS) have developed a cost-effective and scalable strategy to synthesise TMD QDs. The new strategy also allows the properties of TMD QDs to be engineered specifically for different applications, thereby making a leap forward in helping to realise the potential of TMD QDs.

Bottom-up strategy to synthesise TMD QDs

Current synthesis of TMD nanomaterials rely on a top-down approach where TMD mineral ores are collected and broken down from millimetre to nanometre scale via physical or chemical means. This method, while effective in synthesising TMD nanomaterials with precision, is low in scalability and costly as separating the fragments of nanomaterials by size requires multiple purification processes. Using the same method to produce TMD QDs of a consistent size is also extremely difficult due to their minute size.

To overcome this challenge, a team of engineers from the Department of Chemical and Biomolecular Engineering at NUS Faculty of Engineering developed a novel bottom-up synthesis strategy that can consistently construct TMD QDs of a specific size, a cheaper and more scalable method than the conventional top-down approach. The TMD QDs are synthesised by reacting transition metal oxides or chlorides with chalogen precursors under mild aqueous and room temperature conditions. Using the bottom-up approach, the team successfully synthesised a small library of seven TMD QDs and were able to alter their electronic and optical properties accordingly.

Associate Professor David Leong from the Department of Chemical and Biomolecular Engineering at NUS Faculty of Engineering led the development of this new synthesis method. He explained, “Using the bottom-up approach to synthesise TMD QDs is like constructing a building from scratch using concrete, steel and glass component; it gives us full control over the design and features of the building. Similarly, this bottom-up approach allows us to vary the ratio of transition metal ions and chalcogen ions in the reaction to synthesise the TMD QDs with the properties we desire. In addition, through our bottom-up approach, we are able to synthesise new TMD QDs that are not found naturally. They may have new properties that can lead to newer applications.”

Applying TMD QDs in cancer therapy and beyond

The team of NUS engineers then synthesised MoS2 QDs to demonstrate proof-of-concept biomedical applications. Through their experiments, the team showed that the defect properties of MoS2 QDs can be engineered with precision using the bottom-up approach to generate varying levels of oxidative stress, and can therefore be used for photodynamic therapy, an emerging cancer therapy.

“Photodynamic therapy currently utilises photosensitive organic compounds that produce oxidative stress to kill cancer cells. These organic compounds can remain in the body for a few days and patients receiving this kind of photodynamic therapy are advised against unnecessary exposure to bright light. TMD QDs such as MoS2 QDs may offer a safer alternative to these organic compounds as some transition metals like Mo are themselves essential minerals and can be quickly metabolised after the photodynamic treatment. We will conduct further tests to verify this.” Assoc Prof Leong added.

The potential of TMD QDs, however, goes far beyond just biomedical applications. Moving forward, the team is working on expanding its library of TMD QDs using the bottom-up strategy, and to optimise them for other applications such as the next generation TV and electronic device screens, advanced electronics components and even solar cells.

Tags:  2D materials  Graphene 

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Gratomic and TODAQ announce supply chain partnership to track commercial graphene from source to end consumer on the TODA protocol

Posted By Graphene Council, The Graphene Council, Monday, February 4, 2019
Updated: Thursday, January 31, 2019
Gratomic Inc. and TODAQ Holdings are pleased to announce that they have entered into a memorandum of understanding describing the terms of a supply chain partnership to put Gratomic's supply chain and products on the TODA Protocol.

"The market for tires requires products that deliver fuel efficiency, safe handling, and extended wear.  Integrating Gratomic's operations and products onto the TODA-as-a-service ("TaaS") platform with TODAQ as a partner allows us to deliver the desired product efficiently and effectively into the customers hands, with the peace of mind of knowing what they own has been monitored from the raw material source through to the finished product,"said Gratomic's Chairman and co-CEO Sheldon Inwentash.

The project will focus on providing incontrovertible proof of provenance in respect of Gratomic's graphite supply and consequent synthesis of commercial nano engineered graphene products throughout the global graphene marketplace down to the end consumer. 

"We're pleased to add Gratomic as our mining partner alongside our other pharmaceutical and energy supply chain projects. TODAQ is looking forward to adding efficiency and security with scale to Gratomic's operations, providing a brand multiplier that adds confidence to products carrying liberated nano engineered graphene from Gratomic's dedicated graphite source, and of course addressing the potential for forgeries and fakes that can become a constant source of leakage," said Sung Soo Park, TODAQ Managing Director in Seoul.

The project will be rolled out in stages over 2019 as Gratomic brings its end products to market starting with first proof of concepts and staging to commercial delivery of its fuel efficient tire in collaboration with its development partner, Perpetuus Carbon Technologies.  

"Our Graphite mine in Namibia delivers some of the highest quality exceptionally friable graphite for ease of commercial processing. A methodology for monitoring which graphite source is processed into a specific product is a game changer," said Arno Brand, Gratomic's co-CEO.

It is expected that the complete project will span multiple continents with peer-to-peer cross-border settlement of transactions in less than a minute, and aim to efficiently demonstrate results that can commercially scale up looking into 2020. Later phases will also aim to include value-added trade finance services on the TaaS platform.

"The TODA Protocol ensures individual ownership of your own data and TODAQ is here to enable secure and efficient international trade and commoditize the settlement of value. The beauty of this project is that once a customer buys graphene ultra-efficient tires, they own that digital asset and embedded proof of the tire, without requiring any other intermediary including the mine, processor, manufacturing company, retail source or even TODAQ," said TODAQ CEO, Hassan Khan.

Tags:  Graphene  Gratomic  TODAQ Holdings 

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Women in Graphene Career Development Day

Posted By Graphene Council, The Graphene Council, Monday, February 4, 2019
Updated: Monday, February 4, 2019

The "Women In Graphene" initiative within the Graphene Flagship has been set up to help support women and create a more gender diverse scientific community. It aims to connect women working in graphene through biannual meetings and peer to peer support.



Many industries are faced with problems when it comes to gender equality. For example, 99% of female chemists experience a lack of progression in their sector, according to evidence given by the Royal Society of Chemistry (RSC).

The Graphene Flagship, one of our Future & Emerging Technologies (FET) Flagships will host a two day programme – the Women in Graphene Career Development Day – with seminars and workshops aiming to encourage diversity within this field’s community.

This will take place at the National Graphene Institute at the University of Manchester, UK between 11 and 12 February 2019 to coincide with the International Day of Women and Girls in STEM (science, technology, engineering and maths) with the objective of establishing a peer-to-peer support network and reoccurring bi-annual meetings.

NOTICE: THIS EVENT IS NOW FULLY BOOKED!


Tags:  Graphene  The Graphene Flagship 

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Leading Supplier to Composites Companies Adds Graphene to Its Portfolio

Posted By Dexter Johnson, IEEE Spectrum, Friday, February 1, 2019

 

 

As an association trying to support and promote the use of graphene over the last half-decade, The Graphene Council has rightly focused on the interests and developments of the graphene research community as well as those companies marketing graphene materials. In addition, the Council has also sought to serve as an educational platform to help inform other vertical industries about the impact graphene can make on their businesses.

The Graphene Council recently got a boost to its knowledge base on how graphene is perceived by its largest commercial market: composites. Composites Onethe leading supplier in North America of materials and solutions to advanced composites manufacturers, recently joined The Graphene Council as a corporate member. Composites One positions itself as a team of composites experts that can provide insights on the latest advanced materials ranging from advanced fibers, to high-performance thermosets and thermoplastic systems, prepregs, and specialty core materials. The Graphene Council believes Composites One's expertise should reinforce its own knowledge that can then be distributed throughout our community.

To start this knowledge sharing, we took the opportunity to ask Jason Gibson, the Chief Applications Engineer at Composites One, a little bit about their business, how they came to graphene and what kind of outlook the company has for graphene in the composites market.

Q: Could you tell us a bit more about Composites One business, i.e. what kind of composites are you making and for what applications?

A: As North America’s leading provider of solutions for advanced composites manufacturers, Composites One stands ready to assist you, whatever your needs. We utilize the broadest portfolio of advanced raw materials to build comprehensive solutions, bringing you multiple options to meet your needs. Composites One supports our offering with strong technical expertise, along with local service and storage for reduced lead times. We are uniquely capable of handling complex requirements.

Our network of 41 stocking centers throughout the U.S. and Canada, including AS9120 and prepreg freezer locations, along with local delivery on our own fleet of trucks, ensures that your products are there when you need them. All of this is supported by a dedicated team of advanced composites specialists and our 80+ local technical sales representatives.

Q: What are some of the more advanced materials that Composites One has investigated for possibly integrating into your composite offerings?

A: From advanced fibers, to high-performance thermoset and thermoplastic systems, prepregs, specialty core materials, and ancillary products, we have the broadest product offering in the industry.   Our Advanced Composites product managers are specialists in epoxy resin, prepreg, carbon fiber, high performance core, and many other advanced composites solutions.

Q: What made you consider using graphene as a material for your composites, i.e. have you seen other composite manufacturers employing the material, or is it simple due diligence for all emerging materials?

A: We have seen graphene enhance many of the physical properties across the portfolio of resin systems we distribute.  Specifically, we've seen improved toughness, modulus and strength improvements allowing us to fill the needs of engineers and designers at many of our customers.  Composites One focuses on evaluating and distributing cutting edge products that allow us to help our customers meet their goals of improved products.

Q: Can you outline the process by which you would need to test to see if graphene, or any other new material, could be, or should be, integrated into your composites?

A: Composites One works in partnership with our suppliers, industry organizations and academic resources to vet and validate many nano-particles, including graphene.  We maintain a portfolio of diverse nano-particle products that enable us to provide objective solutions to our customers' needs.  This allows us to focus on an optimized solution based on the unique requirements of our customer.

Q: Based on your initial impressions of graphene, where are you expecting the material to fit into your product offerings?

A: We offer graphene in masterbatch form in multiple resin platforms, but focused mainly in our epoxy offerings.  Loadings can vary depending on the desired end results, and offering the masterbatch in the resin side of the epoxy allows for alternative hardening and additive solutions.  We have seen these products have success in multiple markets including sports and recreation, oil and gas, automotive and aerospace.

Q: At this point, what seems to be the issues that remain unclear about graphene, i.e. industry standards, how it will actually integrate into your composites, etc.?

A: Implementing these products into an industrial manufacturing process can be difficult.  Composites One has extensive experience in the process-ability of the nanoparticle enhancements we offer.  We do this in order to help our customers get over the usual hurdle of incorporating it into their manufacturing process.  It can be difficult to implement these solutions and our breadth and depth of experience in this product lines allows us to partner with our customers and help them move forward with minimal difficulties.

Tags:  composites  Composites One  masterbatches  prepregs  thermosets 

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Materials design center receives $25 million grant

Posted By Graphene Council, The Graphene Council, Thursday, January 31, 2019
After spending the past five years solidifying Chicago as a hub for high-tech materials innovation, the second phase of the Chicago-based Center for Hierarchical Materials Design (CHiMaD) has been selected for funding. The National Institute of Standards and Technology (NIST) granted the multi-institutional, Chicago-based center an additional $25 million over the next five years.

CHiMaD is hosted by Northwestern University, with partners that include the University of Chicago, Argonne National Laboratory, QuesTek Innovations and ASM Materials Education Foundation. NIST is also a major collaborator with more than 50 investigators involved in CHiMaD research.

CHiMaD’s mission is to develop a new generation of computational tools, databases and experimental techniques that will enable the design of novel materials to address major societal challenges. The center is also transferring these tools and techniques to industry as well as training the next generation of materials innovators.

“CHiMaD’s central goal is to realize the promise of the Materials Genome Initiative,” said Peter Voorhees, the Frank C. Engelhart Professor of Materials Science and Engineering in Northwestern’s McCormick School of Engineering and one of the center’s three co-directors. “We are designing new materials, ranging from polymers for nanoelectronics to high-temperature metal alloys with the aim to facilitate a faster industrial design cycle of these materials while lowering manufacturing costs. We will also continue to enhance one of the world’s largest public domain collections of materials data that is at the core of our materials design effort.

Gregory B. Olson, the Walter P. Murphy Professor of Materials Science and Engineering at Northwestern and co-director for the center, said: “Building on the Materials Genome infrastructure established in our first five years, we look forward to demonstrating a general methodology of computational materials design by applying our fundamental databases to the creation of novel, high-performance materials for applications ranging from electronics to space travel.”

“CHiMaD brings together the intellectual heft of two major universities in the area of materials design innovation — a national laboratory with deep expertise in materials and advanced computing, a startup company at the forefront of computational materials design, and the processing, characterization and development prowess of NIST,” said Juan de Pablo, the Liew Family Professor in Molecular Engineering and the Vice President for National Laboratories at the University of Chicago and co-director for the center. He continued, “By forming meaningful partnerships with leading companies that rely on fast design cycles to bring products to market at an accelerated pace, CHiMaD has established itself as a national and international thought center for materials innovation at the forefront of technology. The next phase of CHiMaD promises to result in exciting new discoveries that will rapidly find their way into products.” 

Designing materials employs physical theory, advanced computer models, vast materials properties databases and complex computations to accelerate the design of a new material with specific properties for a particular application. Since it launched in 2014, nearly 300 CHiMaD and NIST investigators have developed new materials for batteries, precision nanofabrication, electronics, inks for 3D printing, and structures to withstand extreme environments and more.

CHiMaD specifically focuses on the creation of novel “hierarchical materials,” which exploit distinct structural details at various scales — from the atomic on up — to achieve special, enhanced properties. An example in nature of a hierarchical material is bone, a composite of mineral and protein at the molecular level assembled into microscopic fibrils that in turn are assembled into hollow fibers and on up to the highly complex material that is “bone.” 

CHiMaD works to advance the national Materials Genome Initiative, which aims to accelerate the pace of new materials discovery by combining theoretical, computational and experimental science. Techniques for designing materials have the potential to revolutionize the development of new advanced materials, which in turn have created whole industries. It’s estimated that the average time from laboratory discovery of a new material to its first commercial use can take up to 20 years. The Materials Genome Initiative aims to halve that.

Tags:  Center for Hierarchical Materials Design  CHiMaD  National Institute of Standards and Technology  NIST 

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Promising steps towards large scale production of graphene nanoribbons for electronics

Posted By Graphene Council, The Graphene Council, Thursday, January 31, 2019
Two-dimensional sheets of graphene in the form of ribbons a few tens of nanometers across have unique properties that are highly interesting for use in future electronics. Researchers have now for the first time fully characterised nanoribbons grown in both the two possible configurations on the same wafer with a clear route towards upscaling the production.

Graphene in the form of nanoribbons show so called ballistic transport, which means that the material does not heat up when a current flow through it. This opens up an interesting path towards high speed, low power nanoelectronics. The nanoribbon form may also let graphene behave more like a semiconductor, which is the type of material found in transistors and diodes. The properties of graphene nanoribbons are closely related to the precise structure of the edges of the ribbon. Also, the symmetry of the graphene structure lets the edges take two different configurations, so called zigzag and armchair, depending on the direction of the long respective short edge of the ribbon.

The nanoribbons were grown in two directions along ridges on the substrate. This way both the zigzag- and armchair-edge varieties form and can be studied at the same time. The positions of the atoms in the graphene layer as well as the zig zag edge can be seen from the scanning tunneling microscopy image (Å stands for Ångström, 0.1 nanometers).

The nanoribbons were grown on a template made of silicon carbide under well controlled conditions and thoroughly characterised by a research team from MAX IV Laboratory, Technische Universität Chemnitz, Leibniz Universität Hannover, and Linköping University. The template has ridges running in two different crystallographic directions to let both the armchair and zig-zag varieties of graphene nanoribbons form. The result is a predictable growth of high-quality graphene nanoribbons which have a homogeneity over a millimeter scale and a well-controlled edge structure.

One of the new findings is that the researchers were able to show ballistic transport in the bulk of the nanoribbon. This was possible due to extremely challenging four probe experiments performed at a length scale below 100 nm by the group in Chemnitz, says Alexei Zakharov, one of the authors.

The electrical characterization also shows that the resistance is many times higher in the so called armchair configuration of the ribbon, as opposed to the lower resistance zig-zag form obtained. This hints to a possible band gap opening in the armchair nanoribbons, making them semiconducting. The process used for preparing the template for nanoribbon growth is readily scalable. This means that it would work well for development into the large-scale production of graphene nanoribbons needed to make them a good candidate for a future material in the electronics industry.

So far, we have been looking at nanoribbons which are 30–40 nanometers wide. It’s challenging to make nanoribbons that are 10 nanometers or less, but they would have very interesting electrical properties, and there´s a plan to do that. Then we will also study them at the MAXPEEM beamline, says Zakharov.

The measurements performed at the MAXPEEM beamline was done with a technique not requiring X-rays. The beamline will go into its commissioning phase this spring and will start welcoming users this year.

Tags:  2d materials  Graphene  graphene production 

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Open-source automated chemical vapor deposition system for the production of two-dimensional nanomaterials

Posted By Graphene Council, The Graphene Council, Wednesday, January 30, 2019
Updated: Tuesday, January 29, 2019
A research group at Boise State University led by Assistant Professor David Estrada of the Micron School of Materials Science and Engineering has released the open-source design of a chemical vapor deposition (CVD) system for two-dimensional (2D) materials growth, an advance which could lower the barrier of entry into 2D materials research and expedite 2D materials discovery and translation from the benchtop to the market.

2-dimensional materials are a class of materials that are one to a few atoms thick. The pioneering work of Nobel Laureates Andre Geim and Konstantin Novoselov in isolating and measuring the physical properties of graphene – a 2D form of carbon arranged in a hexagonal crystal structure - ignited the field of 2D materials research

While 2D materials can be obtained from bulk van der Waals crystals (e.g. graphite and MoS2) using a micromechanical cleavage approach enabled by adhesive tapes, the community quickly realized that unlocking the full potential of 2D materials would require advanced manufacturing methods compatible with the semiconductor industry’s infrastructure.

Chemical vapor deposition is a promising approach for scalable synthesis of 2D materials – but automated commercial systems can be cost prohibitive for some research groups and startup companies. In such situations students are often tasked with building custom furnaces, which can be burdensome and time consuming. While there is value in such endeavors, this can limit productivity and increase time to degree completion.

A recent trend in the scientific community has been to develop open-source hardware and software to reduce equipment cost and expedite scientific discovery. Advances in open-source 3-dimensional printing and microcontrollers have resulted in freely available designs of scientific equipment ranging from test tube holders, potentiostats, syringe pumps and microscopes. Estrada and his colleagues have now added a variable pressure chemical vapor deposition system to the inventory of open-source scientific equipment.

“As a graduate student I was fortunate enough that my advisor was able to purchase a commercial chemical vapor deposition system which greatly impacted our ability to quickly grow carbon nanotubes and graphene. This was critical to advancing our scientific investigations,” said Estrada. “When I read scientific articles I am intrigued with the use of the phrase “custom-built furnace” as I now realize how much time and effort graduate students invest in such endeavors.”

The design and qualification of the furnace was accomplished by lead authors Dale Brown, a former Micron School of Materials Science and Engineering graduate student, and Clinical Assistant faculty member Lizandra Godwin, with assistance from the other co-authors. The results of their variable pressure CVD system have been published in PLoS One ("Open-source automated chemical vapor deposition system for the production of two- dimensional nanomaterials") and include the parts list, software drivers, assembly instructions and programs for automated control of synthesis procedures. Using this furnace, the team has demonstrated the growth of graphene, graphene foam, tungsten disulfide and tungsten disulfide – graphene heterostructures.

“Our goal in publishing this design is to alleviate the burden of designing and constructing CVD systems for the early stage graduate student,” said Godwin. “If we can save even a semester of time for a graduate student this can have a significant impact on their time to graduation and their ability to focus on research and advancing the field.”

“We hope others in the community can improve on our design by incorporating open-source software for automated control of 2D materials synthesis,” said Estrada. “Such an improvement could further reduce the barrier to entry for 2D materials research.”

Tags:  2D materials  Boise State University  CVD  Graphene 

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Properties of ‘wonder material’ graphene change in humid conditions

Posted By Graphene Council, The Graphene Council, Tuesday, January 29, 2019
Updated: Friday, January 25, 2019

The ‘wonder material’, which is made from carbon and was discovered in 2004, is hailed for many of its extraordinary characteristics including being stronger than steel, more conductive than copper, light, flexible and transparent.



This study, published in the journal Physical Review B, shows that in bi-layer graphene, which is two sheets of one atom thick carbon stacked together, water seeps between the layers in a humid environment.

The properties of graphene significantly depend on how these carbon layers interact with each other and when water enters in between it can modify the interaction.

The researchers found the water forms an atomically thin layer at 22 per cent relative humidity and separates graphene layers at over 50 per cent relative humidity.

This suggests that layered graphene could exhibit very different properties in a humid place such as Manchester, UK, where average relative humidity is over 80 per cent every month of the year, compared to a dry place such as Tucson, Arizona, where relative humidity is 13 per cent on afternoons in May but rises to 65 per cent on January mornings. So, in Tucson the properties will vary according to the time of the year.

Graphene, both layered and single layer, potentially has a huge number of uses but the results of this study could impact how the material can be used in real-life applications.

Humidity needs to be recorded

Lead author Dr Yiwei Sun, from Queen Mary's School of Engineering and Materials Science, said: “The critical points, 22 per cent and 50 per cent relative humidity, are very common conditions in daily life and these points can be easily crossed. Hence, many of the extraordinary properties of graphene could be modified by water in between graphene layers.”

He added: “Some graphene-based devices may function to their full capability in dry places while others may do so in humid places. We suggest all experiments on 2D materials should in future record the relative humidity.”

The researchers suggest humidity is also likely to have an impact on other layered materials such as boron nitride (sheets made of boron and nitrogen) and Molybdenum disulphide (sheets made of molybdenum and sulphur).

The study was carried out because it was known that graphite, a material also made from carbon, loses its excellent lubricating ability in low humidity conditions, such as aboard aeroplanes at high altitude, which was reported during the Second World War, or in outer space, as reported by NASA in the 1970s.

It was believed that the water in between layers of graphite is crucial to its behaviour and now the same effect has been shown to affect layered graphene.  

Tags:  2D  Bi-layer graphene  Graphene  water  Yiwei Sun 

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Nanotech Energy, the UCLA Energy Incubator and Holder of First Patent for Graphene Announces Profound Achievement in Production of High Quality Graphene Based Materials

Posted By Graphene Council, The Graphene Council, Tuesday, January 29, 2019
Updated: Tuesday, January 29, 2019
Nanotech Energy, a leading supplier of graphene, graphene oxide and graphene super batteries, announced today that it has cleared a monumental hurdle in the production of high-quality graphene-based materials. The first patent for Graphene, now exclusively licensed to Nanotech Energy, was filed in 2002 by Dr. Richard Kaner, Nanotech co-founder and UCLA professor of Chemistry and of Materials Science and Engineering.

Through its proprietary technology, Nanotech Energy is now able to produce graphene with an unsurpassed surface area of over 2,500 meters squared per gram, almost the theoretical limit. A second version of graphene with a surface area of 2,000 to 2,200 meters squared per gram, measured by methylene blue adsorption is available for purchase based on downstream application, while the other version of over 2,500 meters squared per gram is being used only for Nanotech’s downstream products.

Graphene is a single layer of carbon with a theoretical surface area limit of slightly over 2,600 meters squared per gram. The surface area determines how many electrons can be stored and, in turn, how much energy can be stored in batteries and supercapacitors. Without the large surface area, graphene loses most of its superlatives and behaves just like graphite.

Jack Kavanaugh, Nanotech founder and CEO said, ”Nanotech Energy has created a remarkable technology that reaches the boundaries of superior energy density, power density, cycle life and, most importantly, safety. It’s an exciting time for the company and the industry.”

Dr. Maher El-Kady added “it’s widely accepted that the properties of graphene vary depending on the number of layers. The high surface area of our graphene has potential to dramatically transform the graphene industry. We already produce super-batteries, supercapacitors, conductive inks and conductive epoxies with unprecedented performance and have responsibly extended our leads in each of those arenas by making them all safer.”

Dr. Kaner further added, “After tests have demonstrated that almost all graphene sold today is really thin layer graphite and not graphene, this is a major step forward to be able to scale real graphene with a surface area (over 2500 m 2 /g) that approaches the theoretical limit.”

Tags:  Batteries  Graphene  graphene oxide  Nanotech Energy 

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Creating a roadmap for 2-D materials

Posted By Graphene Council, The Graphene Council, Monday, January 28, 2019
Updated: Monday, January 28, 2019


The rapid growth of research on 2-D materials – materials such as graphene and others that are a single or few atoms thick – is fueled by the hope of developing better performing sensors for health and environment, more economical solar energy, and higher performing and more energy efficient electronics than is possible with current silicon electronics.



Technical roadmaps, such as the International Technology Roadmap for Semiconductors (ITRS), first published in 1998, serve as guides for future advances in a particular field and provide a means for organizations to plan for investments in new technology.

An invited article in the December online edition of the journal 2-D Materials provides a roadmap for the synthesis of electronic-grade two-dimensional materials for future electronic and sensing applications. Led by Penn State, with contributions from five additional universities and national laboratories, the roadmap addresses the grand challenges in 2-D materials with useful electronic or photonic properties, and the outlook for U.S. advances in the field.

"This article is a review of where we currently are in regard to the synthesis of 2-D materials and our thoughts on the top research priorities that need to be addressed to achieve electronic grade 2-D materials," said Joshua Robinson, associate professor of materials science and engineering, whose Ph.D. students Natalie Briggs and Shruti Subramanian are co-lead authors on the report titled "A Roadmap for Electronic Grade 2-Dimensional Materials," published online today, Jan. 17.

The authors divided the paper into four parts: Grand Challenges, which are the technology drivers, such as the internet of things; Synthesis, the techniques and theories required to grow close to perfect 2-D materials; Materials Engineering, which is fine tuning the properties of 2-D and composite materials; and finally, Outlook, which is the future of electronic devices when silicon technology reaches an inevitable roadblock.

"To put our roadmap together, we reached out to experts in various subfields, such as different synthesis approaches, defect engineering and computational theory," said Briggs of the two-year project. "We asked them to talk about the key fundamental challenges and the steps required to address these challenges in their area of expertise."

Robinson added, "This is the first roadmap focused on 2-D synthesis for electronic applications and there are still a lot of open questions. We want to bring some of those topics into the light."

A list of the twenty authors and their affiliations can be found online in the open access article in 2-D Materials.

Tags:  2D materials  Graphene  International Technology Roadmap for Semiconductor 

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Graphene and related materials safety: human health and the environment

Posted By Graphene Council, The Graphene Council, Monday, January 28, 2019
Updated: Friday, January 25, 2019

As the drive to commercialise graphene continues, it is important that all safety aspects are thoroughly researched and understood. The Graphene Flagship project has a dedicated Work Package studying the impact of graphene and related materials on our health, as well as their environmental impact. This enables safety by design to become a core part of innovation.



Researches and companies are currently using a range of materials such as few layered graphene, graphene oxide and heterostructures. The first step to assess the toxicology is to fully characterise these materials. This work overviews the production and characterisation methods, and considers different materials, which biological effects depend on their inherent properties.

"One of the key messages is that this family of materials has varying properties, thus displaying varying biological effects. It is important to emphasize the need not only for a systematic analysis of well-characterized graphene-based materials, but also the importance of using standardised in vitro or in vivo assays for the safety assessment," says Bengt Fadeel, lead author of this paper working at Graphene Flagship partner Karolinska Institutet, Sweden.

"This review correlates the physicochemical characteristics of graphene and related materials to the biological effects. A classification based on lateral dimensions, number of layers and carbon-to-oxygen ratio allows us to describe the parameters that can alter graphene's toxicology. This can orient future development and use of these materials," explains Alberto Bianco, from Graphene Flagship partner CNRS, France and deputy leader of the Graphene Flagship Work Package on Health and Environment.

The paper gives a comprehensive overview of all aspects of graphene health and environmental impact, focussing on the potential interactions of graphene-based materials with key target organs including immune system, skin, lungs, cardiovascular system, gastrointestinal system, central nervous system, reproductive system, as well as a wide range of other organisms including bacteria, algae, plants, invertebrates, and vertebrates in various ecosystems.

"One cannot draw conclusions from previous work on other carbon-based materials such as carbon nanotubes and extrapolate to graphene. Graphene-based materials are less cytotoxic when compared to carbon nanotubes and graphene oxide is readily degradable by cells of the immune system," comments Fadeel.

Andrea C. Ferrari, Science and Technology Officer of the Graphene Flagship and Chair of its Management Panel added that "understanding any potential Health and Environmental impacts of graphene and related materials has been at the core of all Graphene Flagship activities since day one. This review provides a solid guide for the safe use of these materials, a key step towards their widespread utilization as targeted by our innovation and technology roadmap."

Tags:  Graphene  graphene oxide  Healthcare  The Graphene Flagship 

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Drilling speed increased by 20% – yet another upgrade in the oil & gas sector made possible by graphene nanotubes

Posted By Graphene Council, The Graphene Council, Friday, January 25, 2019
Updated: Friday, January 25, 2019

56% of drilling tool failures in the oil extraction industry are caused by low durability of the rubber stator – one of the most important elements in a screw drill. In China, annual losses from the failure of drilling tools are estimated to be more than $40,000 per oil well. Equipment manufacturers are thus always looking for ways to improve the rubber used in screw drilling tools, to reduce these financial losses for oil-extracting companies.

One of the largest Chinese producers of PDM drilling tools, Orient Energy & Technology Ltd., has completed laboratory testing of nitrile butadiene rubber (NBR) containing TUBALL graphene nanotubes, produced by OCSiAl. Just 1.7 wt.% of graphene nanotube concentrate introduced into NBR was found to increase the tensile modulus by 30%.

“Improving the modulus of elasticity is the most valuable advantage of graphene nanotubes in our industry, because that leads to a 30% increase in output torque of our products. With that, the drilling speed can also be increased by more than 20%, resulting in a shortened drilling cycle, reduced energy consumption and less environmental pollution, greatly improving China’s drilling technology,” said Mr. Hu, a rubber engineer at Orient Energy & Technology. At the same time, the graphene nanotubes result in a reduction of abrasion by 20% without increasing the Mooney viscosity of rubber, whereas other additives such as multi wall carbon nanotubes increase viscosity, which is unacceptable for injecting.



Graphene nanotubes are one of the allotropic forms of carbon, where each tube can be considered to be a rolled-up sheet of graphene. This universal additive is already on duty protecting the oil & gas industry, where it is widely applied as a conductive additive in fiberglass pipes for permanent and uniform conductivity, as well as 15% reinforcement. Another example is anti-static fiberglass tanks for storing and transporting easily combustible materials, where these nanotubes ensure permanent and stable resistivity of less than 10^6 Ω·cm, without “hot spots” and independent of humidity.

Orient Energy & Technology is continuing to test TUBALL graphene nanotubes, in particular by studying their effects on other types of rubber, such as HNBR and FKM. Meanwhile, the first industrial prototype of a TUBALL-enhanced NBR stator for a screw drill is undergoing industrial trials.

Tags:  Carbon Nanotubes  Graphene  TUBALL 

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Gratomic to Launch New Graphene Ultra Efficient Tires

Posted By Graphene Council, The Graphene Council, Thursday, January 24, 2019
Updated: Thursday, January 24, 2019

Gratomic Inc. a vertically integrated graphite to graphenes, advanced materials company is pleased to announce the development of Gratomic's new Graphene Ultra Fuel Efficient Tires (GUET) with certification and terrain testing targeted for completion in Q3, 2019.

"Purely from a demand perspective, we have been pulled into a market which represents a very large opportunity for Gratomic. Simply put, our customers want what we have; high quality graphene. Not only are Hybrid Graphene enhanced tires fuel efficient, but they can also demonstrate better handling and longer life" commented Gratomic's Chairman and Co-CEO Sheldon Inwentash. "The GUET tire market represents a very large vertical for Gratomic which the Company will be vigorously pursuing in 2019, and beyond."

Gratomic recognizes the automotive tire market is large and is expected to grow to 2.5 billion tires by 2022. Gratomic looks to penetrate and disrupt the traditional means of tire production by providing graphene enabled GUET tires. To date, the global tire market has recognized that employing graphenes within tire treads, walls and the inner linings can make tires lighter, provide better grip and reduce rolling resistance to an extent that is not possible with existing tire compounds. On average, this would require 20 to 25 grams of graphene per tire. However, for the Industry, specification consistency and scaleability of supply have been limiting factors and to date have been the biggest constraints in commercializing Graphene.

Attributed to the right combination of geology at the mine and our processing partner, Gratomic strongly believes it can satisfy the supply demand of quality graphenes required for what the Company believes is the growing market demand for a new age economy tire. Gratomic is confident in its ability to deliver consistent quality and quantities of Graphenes to end users.

Gratomic has been able to achieve this through a unique collaboration agreement with its development partner Perpetuus Carbon Technologies who currently supplies substantial quantities of surface modified graphenes on a monthly basis to the tire industry through its Patented Plasma Process.

Ian Walters Director - Perpetuus Carbon Technologies Limited stated:

"Perpetuus' investigative analysis and characterization has concluded that the Graphenes derived from the Gratomic mine are highly friable, more so than any other graphite tested for purpose by the Perpetuus Labs. The liberated graphenes when functionalized have demonstrated excellent processability. Initial application in a host of end uses has demonstrated excellent suitability for a range of products. Most noteworthy are the excellent results generated when the Hybrid Graphenes are included in elastomers for tire construction. Perpetuus looks forward to working with Gratomic to launch probably the first range of Graphene enabled ultra fuel efficient tires."

Employing its dedicated facility for the patented Perpetuus plasma method Gratomic post plasma processing produces graphenes (less than 10 layers) of a high purity (CK 99.10%) derived from its Graphite Mine in Namibia.

Tags:  Automotive tyres  Graphene  Gratomic  Perpetuus  Tires 

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Graphene Technology to Deice Aircraft Enters $1.30 Billion Deicing Market, Time Saving, More Efficient & Less Toxic

Posted By Graphene Council, The Graphene Council, Wednesday, January 23, 2019

Mr. Tom Donaldson, President, Signet International Holdings, Inc., the parent company of Signet Graphene Technologies, Inc. (SGT), announced recently that the company has executed a contract with Florida International University (FIU) to further the development and commercialization of a new deicing technology enhanced by graphene, the revolutionary carbon-based nanotechnology.

Adhesion of ice to the surfaces of aircraft in inclement weather severely compromises aircraft aerodynamic performance. Time-consuming airport deicing operations are performed for safety, causing extensive flight delays for travelers and a heavy financial burden for the airline industry. Airport Lifestyle magazine notes that the average cost of deicing a passenger aircraft is over $7,000 per coating.

A team of engineers at Florida International University headed up by Professor Arvind Agarwal, PhD, Chair of Mechanical and Materials Engineering and his team in Plasma Forming Laboratory: Ms Jenniffer Bustillos, Dr. Cheng Zhang and Dr. Benjamin Boesl have developed a graphene foam−polymer composite with superior deicing efficiency and strength. A patent for the technology will be issued on Jan. 22, 2019.

The graphene-foam polymer composite provides lightweight coatings and free-standing components with heating abilities, with exceptional thermal stability. The graphene reinforcement also increases the tensile strength of the polymer coating on the aircraft and reduces the impact of nasty toxic chemical runoff seeping into the ground and water.

The patent application entitled, “Three Dimensional Graphene Foam Reinforced Composite Coating & Deicing Systems Therefrom,” was a result of research conducted by a grant from the U.S. Army Research Office. Signet Graphene Technologies, Inc., intends to further develop the technology and make it ready for mass production. This invention is expected to have a major impact on the aircraft deicing market, which, according to Opus Materials Technologies, the U.S. spends over $1.30 billion in deicing fluids alone.

“This contract marks the first of an exciting ongoing relationship with FIU,” says Donaldson. “This invention is the solution to a very practical problem in air transportation. Critically low temperature conditions are the reasons delays are imminent, costing the airlines and travelers time and money. Although our focus is on time and safety in the airline industry, we are discovering an abundance of uses for this technology. In fact, we are exploring applied applications in solving icing conditions from icy steps; turbine blades and their mechanics, helicopter rotor blades; even private home uses and other subzero problems.”

“It is a pleasure to be associated with FIU,” says Ernest Letiziano, CEO, SIGN. “We were looking for applied use of graphene that can be made available to the public quickly; this invention is the answer to efficiency and toxic waste. The Army Grant technology has been achieved; we will take it from here.”

Tags:  Florida International University  Graphene  Signet Graphene Technologies 

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The ‘Holey graphene’ membrane has been elected ‘Molecule of the year 2018’ by the C&EN journal

Posted By Graphene Council, The Graphene Council, Wednesday, January 16, 2019
Updated: Wednesday, January 16, 2019

Readers of the journal of the American Chemical Society have elected this graphene membrane with pores controlled at the atomic scale as the best molecule of 2018. This structure was presented in Science in a joint article by researchers from the ICN2, the CiQUS and the DIPC.

The porous graphene membrane synthesized by researchers from the Institut Català de Nanociència i Nanotecnologia (ICN2, a center of BIST and CSIC), the Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and The Donostia International Physics Center (DIPC) has been elected as the molecule of the year by the readers of C&EN magazine of the American Chemical Society with 58% of the votes among 8 international candidates.

Science magazine published this milestone in April in a work directed by the ICN2 Group Leader ICREA Prof. Aitor Mugarza and CiQUS IP Dr. Diego Peña. The article explained the potential of this precious material for applications in electronics, filters and sensors. The results of this study, whose first author is Dr. César Moreno from the ICN2, conducted with the molecule synthesized at CiQUS by Dr. Manuel Vilas Varela made possible the application for a patent.

The presence of pores in graphene pores whose size, shape and density can be tuned with atomic precision at the nanoscale can modify its basic structure and make it suitable as a selective filter for extremely small substances, from greenhouse gases to salt, to biomolecules. In addition, graphene becomes a semiconductor when the space between pores is reduced to a few atoms, opening the door for its use in electronic applications, where it could be used to replace the bulkier, more rigid silicon components used today.

Applied in conjunction, these two properties are predicted to allow the development of combined filter and sensor devices which will not only sort for specific molecules, but will alternatively block or monitor their passage though the nanopores using an electric field.

The resulting graphene exhibits electrical properties akin to those of silicon which can also act as a highly-selective molecular sieve. Applied in conjunction, these two properties are predicted to allow the development of combined filter and sensor devices which will not only sort for specific molecules, but will alternatively block or monitor their passage though the nanopores using an electric field.

Tags:  Graphene 

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Graphene hits the right note at high frequencies

Posted By Graphene Council, The Graphene Council, Tuesday, January 15, 2019

Graphene holds the potential to deliver a new generation of ultrafast electronic devices. Current silicon technology can achieve clock rates – a measure of how fast devices can switch – of several hundred gigahertz (GHz). Graphene could achieve clock rates up to a thousand times faster, propelling electronics into the terahertz (THz) range. But, until now, graphene’s ability to convert oscillating electromagnetic signals into higher frequency modes has been just a theoretical prediction.


Now researchers from the Helmholtz Zentrum DresdenRossendorf (HZDR) and University of Duisburg-Essen (UDE), in collaboration with the director of the Max Planck Institute for Polymer Research (MPI-P) Mischa Bonn and other researchers, have shown that graphene can covert high frequency gigahertz signals into the terahertz range [Hafez et al., Nature (2018)].

“We have been able to provide the first direct proof of frequency multiplication from gigahertz to terahertz in a graphene monolayer and to generate electronic signals in the terahertz range with remarkable efficiency,” explain Michael Gensch of HZDR and Dmitry Turchinovich of UDE.

Using the novel superconducting accelerator TELBE terahertz radiation source at HZDR’s ELBE Center for High-Power Radiation Sources, the researchers bombarded chemical vapor deposition (CVD)-produced graphene with electromagnetic pulses in the frequency range 300–680 GHz. As previous theoretical calculations have predicted, the results show that graphene is able to convert these pulses into signals with three, five, or seven times the initial frequency, reaching the terahertz range.

“We were not only able to demonstrate a long-predicted effect in graphene experimentally for the first time, but also to understand it quantitatively at the same time,” points out Turchinovich.

By doping the graphene, the researchers created a high proportion of free electrons or a so-called Fermi liquid. When an external oscillating field excites these free electrons, rather like a normal liquid, they heat up and share their energy with surrounding electrons. The hot electrons form a vapor-like state, just like an evaporating liquid. When the hot Fermi vapor phase cools, it returns to its liquid form extremely quickly. The transition back and forth between these vapor and liquid phases in graphene induces a corresponding change in its conductivity. This very rapid oscillation in conductivity drives the frequency multiplication effect.

“In theory, [this] should allow clock rates up to a thousand times faster than today’s silicon-based electronics,” say Gensch and Turchinovich.

The conversion efficiency of graphene is at least 7–18 orders of magnitude more efficient than other electronic materials, the researchers point out. Since the effect has been demonstrated with mass-produced CVD graphene, they believe there are no real obstacles to overcome other than the engineering challenge of integrating graphene into circuits.

“Our discovery is groundbreaking,” says Bonn. “We have demonstrated that carbon-based electronics can operate extremely efficiently at ultrafast rates. Ultrafast hybrid components made of graphene and traditional semiconductors are also now conceivable.”

Nathalie Vermeulen, professor in the Brussels Photonics group (B-PHOT) at Vrije Universiteit Brussel (VUB) in Belgium, agrees that the work is a major breakthrough.

“The nonlinear-optical physics of graphene is an insufficiently understood field, with experimental results often differing from theoretical predictions,” she says. “These new insights, however, shine new light on the nonlinear-optical behavior of graphene in the terahertz regime.”

The researchers’ experimental findings are clearly supported by corresponding theory, Vermeulen adds, which is very convincing.

“It is not often that major advances in fundamental scientific understanding and practical applications go hand in hand, but I believe it is the case here,” she says. “The demonstration of such efficient high-harmonic terahertz generation at room temperature is very powerful and paves the way for concrete application possibilities.”

The advance could extend the functionality of graphene transistors into high-frequency optoelectronic applications and opens up the possibility of similar behavior in other two-dimensional Dirac materials. Marc Dignam of Queen’s University in Canada is also positive about the technological innovations that the demonstration of monolayer graphene’s nonlinear response to terahertz fields could open up.

“The experiments are performed at room temperature in air and, given the relatively short scattering time, it is evident that harmonic generation will occur for relatively moderate field amplitudes, even in samples that are not particularly pristine,” he points out. “This indicates that such harmonic generation could find its way into future devices, once higher-efficiency guiding structures, such as waveguides, are employed.”

He believes that the key to the success of the work is the low-noise, multi-cycle terahertz source (TELBE) used by the researchers. However, Dignam is less convinced by the team’s theoretical explanation of graphene’s nonlinear response. No doubt these exciting results will spur further microscopic theoretical investigations examining carrier dynamics in graphene in more detail.

Tags:  CVD  Electronics  Graphene  graphene production  Terahertz 

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Bellwether Specialty Chemical Company Leads the Way in Graphene

Posted By Dexter Johnson, IEEE Spectrum, Monday, January 14, 2019

Back a decade-and-a-half ago when the term “nanotechnology” was first garnering interest from the investment community, the UK-based specialty chemical company Thomas Swan had already launched into producing single-walled carbon nanotubes (SWCNTs) on a commercial scale. Having an established chemical company like Thomas Swan engaging commercially in nanomaterials provided a kind of imprimatur of respect that nanomaterials and nanotechnology were for real and not just some lab experiment.

Now Thomas Swan has added to their portfolio of nanomaterials by offering graphene and the two-dimensional version of the insulator boron nitride. This move, in its own way, provides another imprimatur that graphene and its commercial aspirations are for real and that the marketplace will need to take greater notice.

Thomas Swan has now joined The Graphene Council as a Corporate Member and with this new membership we took the opportunity to talk to Michael Edwards, the Business Director of Advanced materials at Thomas Swan, to get some further insight into why the company has entered the graphene business, how that business relates to their SWCNT business and how the company expects to see their graphene business as well as the market in general develop in the near future.

Q: Thomas Swan was one of the first established specialty chemical companies that got involved the manufacturing and development of nanomaterials, going back to your involvement in single-walled carbon nanotubes (SWCNTs) and now with graphene. What has been the reasoning that led Thomas Swan to enter these business lines so early?

A: It's always bee the vision of Harry Swan, to be honest with you. Harry is the owner of our business. He's the fourth generation of Swan. His initial involvement in the business was with carbon nanotubes, and subsequently, advanced materials.

We feel that it's an extension to the chemicals business. It provides leverage into different markets. Carbon nanotubes and subsequently graphene and now more recently, boron nitride, it is more the same; it's an extension of the business unit and a continuation of wanting to be at the forefront of technology.

Q: As mentioned, Thomas Swan has long been a producer of SWCNTs. What have you learned from your SWCNTs business that informs your graphene business? What are the differences between those two lines of business and what are their synergies?

A: What we learned from the CNT business was not to be too optimistic about forecasts. There's a lot of hype with new technology as the Gartner hype curve suggests. There are a lot of innovative start-up companies, some with a lot of early investment who are prepared to lead you down their vision of the end-goal. We've spent probably more than £10 million in investment in the two technologies over the last 10 years. We have capability for production, in volume that we can start immediately.

What we've learned is to be a little bit more patient with those new markets, understand the breadths and depths of them, and know that you have to talk to world leading manufacturers as well as innovators in order to get your overall perspective and product correct.  

The synergies are in the characterization that you need to do. You need to have a different type of person scientifically between chemistry and materials. That was a good learning. In a sense carbon nanotubes and graphene are the same, but carbon nanotubes and graphene require a different approach to the chemicals business that we have. We have had to form a dedicated team but can still call on expertise in the areas of production, QA, Logistics, etc.

We need to have a different business development outlook instead of having established account management principles and long-term customer relationships, we need to use modern-day marketing methods such as lead generation, closing leads, social media tools and pipeline management, but all the while understanding a lot more about your end customers' application as business development has always been done

Graphene and carbon nanotubes are different in the respect that whilst they are both supply chain materials, graphene is far more of an additive than carbon nanotubes appears to be. In a sense, it's further down the food chain. You've got a diagram in the Graphene Council Bulk Graphene Report, which I use extensively, which shows the various different types of graphene.

Graphene tends to be a lot more difficult and it's more of an additive. You're getting far less benefit in graphene than you appear to be getting in carbon nanotubes unless you go to the right-hand side of that form and you reach what I call utopia, which is trying to meet that pristine, graphene defect-free perfect product.

Q: Could you give a bit more background on the type of graphene you're producing? The manufacturing process you employ, the markets you target for your graphene products?

A: We have an exclusive licensee for Trinity College Dublin's liquid-phase exfoliation, high-shear method. We manufacture using liquid phase exfoliation, but we have extended that to our own patents using homogenizers, which have a slightly different method of liquid-phase exfoliation.

We have a version of the technology in which we're up to tens-of-kilograms towards hundreds-of-kilograms production capacity with manufacturing capability today of few layer graphene, multilayer graphene. Using our scaled up technology adopting homogenization, we have graphene nanoplatelets with a capacity today up to about 20 tons. The beauty of this technology, and they're both patented and licensed to us, is that it's a linear scale up. We can quite readily move up to thousands of tons capability on the graphene nanoplatelets.

The areas that we're targeting are composites, lubricants, inks, coatings, and we're doing early work in battery technology. Also, since we have boron nitride, we are working hard in barrier coatings and thermal interface coatings as well. We offer both solutions in that area. With SWCNT’s we can address the semiconductor memory and battery chemistry areas also. 

Q: Thomas Swan also manufactures other two-dimensional materials, namely molybdenum disulfide (a semiconductor) and boron nitride (an insulator), correct? Are you making heterogeneous materials with these other 2D materials?

A: We haven't really done a lot of work with molybdenum disulfide. Part of that is because—this goes back to that chain of command of graphene products—that tends to be a semiconductor. You tend to need to have your business development team focused on a different market. 

The boron nitride that we're working on, as I said, fits quite neatly alongside graphene. Often we can sell our powders dispersion or masterbatches as boron nitride or graphene. It gives us the flexibility to talk to customers. That's basically the way that we're going to market.

Q: How far do you see your company moving up the value chain of 2D materials? Will the company consider making devices with the materials you are producing? Where would the company draw the line in moving up the value chain?

A: Well, the company itself is mainly a performance chemicals company, toll- manufacturing and now advanced materials company. The extent to which I think we’ll move up the value chain probably will stop at masterbatches, inks and maybe coatings,. Based on the fact that we've got a global reach with major global corporates, our preferred approach is to work with these guys’ R&D teams, and we will get put right back in our place if we try to overextend. 

We sit in the value chain, we provide good value, we have a very strong manufacturing ethos with capability for operations and distribution outlets around the globe already in place. I believe we know where we fit in our value chain and it will extend no further than what I've mentioned.

Having said that, and going back to the question about what technology we have, we have just patented a technology, which allows us to do a bottom-up process. We’ll be able to talk more about that in the next month-or-so. However, we have filed the patent and it's a process that allows us to use our current processing technology. Furthermore, it allows us to produce some forms of functionalized graphene. There will be news on this over the next couple of months in terms of each detail and our marketing strategy.

I believe, as we move up the application chain, we add more value to our customers potential. It will certainly add to our base product road map, but we always try to add more to our service to our customers by offering them an option, utilizing the strengths of our R&D team here. Potentially it's a good solution because we've already trialed this with our production technique. It's another string to our bow.

Q: What do you see for the future of graphene’s commercial interests, i.e. a reduction of the number of applications or an increase, market consolidation for both producers and buyers, etc.?

A: I think it's a rationalisation more than anything. I think there will be a commodity graphene area, which is looking at areas such as tyres and carbon black in that space as well as asphalt/concrete where you'll really need to get high volume producers who are capable of getting the price down significantly.

There will also be that niche middle ground where we will palce ourselves, adding value to a customer’s product, trying to get 10% to 20% improvement on one or two parameters of that product to give them access to the market, and therefore you'll have be influential in their overall value proposition.

It's that high-end electronics defect-limited, single-sheet graphene which is going into the electronics field. To some extent, that's also where our single-wall carbon nanotubes may end up is in that electronics field where you're adding some value. Maybe even in batteries. That will get a little bit smarter. I believe therefore there are three distinct categories and the definition of those various graphene subsets probably help in that definition.

We won't be a huge volume manufacturer, typically hundreds to thousands tonnes annually, but our technology might well lend itself to helping our customers in their specific niches.

You can already see some of our competition linking themselves to mines, and talking about really high volume. I think there’s room for a few of these companies, but we probably won't play in that area.

Q: At this point, do you believe that a lack of standards poses a real limiting factor the commercial expansion of graphene?

A: I think the recent definition is helping clarify the situation. I think a lack of standards is always a problem, and it prevents major players doing anything more than dipping their toe in the water. I absolutely agree that  standards will help drive the market. I believe it will help define both product and applications far more clearly.

Tags:  Bulk Graphene Pricing Report  Graphene  Michael Edwards  SWCNT  Thomas Swan 

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UVA researchers devise method for converting retired Li-ion anodes to graphene and GO

Posted By Terrance Barkan, Saturday, December 29, 2018

Researchers at the University of Virginia (UVA) have devised a process for converting retired Li-ion battery anodes to graphene and graphene oxide (GO). A paper on the work is published in the ACS journal Nano Letters.

Schematic illustration of the proposed smart fabrication of graphene and graphene oxide from end-of-life batteries. Zhang et al.

… accompanying the booming expansion of the Li-ion battery market, a tremendous amount of batteries retire every year and most of them are disposed of in landfills, which not only causes severe waste of precious sources but also induces hazardous soil contamination due to the plastic components and toxic electrolytes. So far, only 1% of end-of-life Li-ion batteries have been recycled. Apparently, it is an urgent necessity to develop effective battery recycling techniques. 

… A rational strategy to simultaneously solve the environmental issues from waste batteries and graphite mining is to fabricate graphene directly from end-of-life battery anodes.

 

… Here, graphite powders from end-of-life Li-ion battery anodes were used to fabricate graphene.

—Zhang et al.

Graphite powders collected from end-of-life Li-ion batteries exhibited irregular expansion because of the lithium-ion intercalation and deintercalation in the anode graphite during battery charge/discharge. 

Such lattice expansion of graphite can be considered as a prefabrication of graphene because it weakened the van der Waals bonds and facilitated the exfoliation. 

—Zhang et al.

 

This “prefabrication” process facilitates both chemical and physical exfoliations of the graphite. Comparing with the graphene oxide derived from pristine, untreated graphite, the graphene oxide from anode graphite exhibited excellent homogeneity and electrochemical properties. 

The lithiation aided pre-expansion enabled 4 times enhancement of graphene productivity by shear mixing, the researchers found. 

The graphene fabrication was seamlessly inserted into the currently used battery recycling streamline in which acid treatment was found to further swell the graphite lattice, pushing up the graphene productivity to 83.7% (10 times higher than that of pristine graphite powders).

Tags:  Batteries  Graphene  graphene oxide  Li-ion  Li-ion batteries  UVA 

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