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High-safety, flexible and scalable Zn//MnO2 rechargeable planar micro-batteries

Posted By Graphene Council, The Graphene Council, Thursday, July 18, 2019
Updated: Monday, July 15, 2019
Increasing development of micro-scale electronics has stimulated demand of the corresponding micro-scale power sources, especially for micro-batteries (MBs). However, complex manufacturing process and poor flexibility of the traditional stacked batteries have hindered their practical applications.

Planar MBs have recently garnered great attention due to their simple miniaturization, facile serial/parallel integration and capability of working without separator membranes. Furthermore, planar geometry has extremely short ion diffusion pathway, which is attributed to full integration of printed electronics on a single substrate. Also, in order to get rid of the safety issues induced by the flammable organic electrolyte, the aqueous electrolyte, characterized by intrinsic nonflammability, high ionic conductivity, and nontoxicity, is a promising candidate for large-scale wearable and flexible MB applications. As the consequence, various printing techniques have been used for fabricating planar aqueous MBs. "In particular, screen printing can effectively control the precise pattern design with adjustable rheology of the inks, and is very promising for large-scale application." The author said.

In a new article published in Beijing-based National Science Review, Zhong-Shuai Wu at Dalian Institute of Chemical Physics, Chinese Academy of Sciences, constructed aqueous rechargeable planar Zn//MnO2 batteries by an applicable and cost-effective screen printing strategy. "The planar Zn//MnO2 micro-batteries, free of separators, were manufactured by directly printing the zinc ink as the anode and γ-MnO2 ink as the cathode, high-quality graphene ink as metal-free current collectors, working in environmentally benign neutral aqueous electrolytes of 2 M ZnSO4 and 0.5 M MnSO4." The author stated. Diverse shapes of Zn//MnO2 MBs were fabricated onto different substrates, implying the potential for widespread applications.

The planar separator-free Zn//MnO2 MBs, tested in neutral aqueous electrolyte, deliver high volumetric capacity of 19.3 mAh/cm3 (corresponding to 393 mAh/g), at 7.5 mA/cm3, and notable volumetric energy density of 17.3 mWh/cm3, outperforming lithium thin-film batteries (<=10 mWh/cm3). Moreover, The Zn//MnO2 planar MBs present long-term cyclability, holding high capacity retention of 83.9% after 1300 times at 5 C, superior to stacked Zn//MnO2 MBs reported. Also, Zn//MnO2 planar MBs exhibit exceptional flexibility without observable capacity decay under serious deformation, and remarkable serial and parallel integration of constructing bipolar cells with high voltage and capacity output.

This satisfactory result will open numerous intriguing opportunities in various applications of intelligent, printed and miniaturized electronics. Also, this work will inspire scientists working in nanotechnology, chemistry, material science and energy storage, and may have significant impact on both future technological development of planar micro-scale energy-storage devices and research of graphene based materials.

Tags:  Batteries  Dalian Institute of Chemical Physics  Energy Storage  Graphene  Zhong-Shuai Wu 

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AGM advances applications for water based anti-corrosion coatings

Posted By Graphene Council, The Graphene Council, Thursday, July 18, 2019
Updated: Monday, July 15, 2019

Applied Graphene Materials, the producer of specialty graphene materials, has announced it has achieved significant technological progress (patent pending) on the deployment of graphene into water-based coatings to enhance their barrier properties.

Water-based coating development remains a focus for industry formulators.

This push is driven by the continuing tightening of regulations brought in to lessen the detrimental impact that solvent- based coatings have on both worker health and the environment. As the technology for water-based coatings continues to evolve, one of the key challenges that remains is to significantly improve their anti-corrosion performance. In doing so, this will fully extend their use away from decorative applications into broader industrial protective coatings.

Over recent years AGM has proven the outstanding barrier and anti-corrosion performance gains possible by incorporating graphene into solvent-based coating systems using its Genable® dispersion technology. This has been demonstrated with several commercial products reaching industrial end-user markets. However, effective incorporation of graphene into water-based systems has previously proven more problematic due to interrelated issues around materials compatibility and film formation.

This water-based breakthrough is again based on AGM's platform Genable® technology, a range of master dispersions that are designed to facilitate the easy incorporation of graphene into coating formulations and existing processes. Genable® dispersions are fully scalable industrial products and, based on initial findings, the addition levels required to significantly enhance anti-corrosion performance in water-based systems are low enough to ensure commercial viability, even in light industrial applications.

Adrian Potts, CEO of Applied Graphene Materials, said:
"A key driver for coatings developers to upgrade their product formulations is increasing regulatory pressure to improve the environmental impact and safety of their products. This is why AGM is working to replicate the success we have already achieved with the incorporation of our Genable® products into solvent-based products with its incorporation into water-based products. We are delighted to be able to present significant technological progress to our customers, reaffirming AGM as the leader in the development of cutting-edge graphene applications tailored to add significant value for paints and coatings manufacturers."

While the findings being shared publicly are in a commercial acrylic DTM (Direct-to-Metal) coating, AGM believes that water-based Genable® technology could, with considered formulating, equally well be adopted into epoxy chemistries and likewise into more complex formulated primer systems.



AGM remains the industry leader for graphene exploitation into the global paints and coatings industry, boasting a highly experienced formulations and applications team, supported by a well-equipped product development and characterisation laboratory and production capability for consistent manufacturing.

Tags:  Adrian Potts  Applied Graphene Materials  Coatings  Corrosion  Graphene 

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Leading Graphene Innovator Sees Graphene Market at a Tipping Point

Posted By Dexter Johnson, IEEE Spectrum, Wednesday, July 17, 2019

The Global Graphene Group (G3) has a 17-year relationship with graphene since Dr. Bor Jang, cofounder of Nanotek Instruments, Inc., discovered graphene in 2002.

Today, the G3 organization currently consists of three groupings of companies. First, there is Nanotek Instruments that holds the over three hundred patents the company has filed since its inception in 1997.

Another of the three branches involves graphene production and this branch includes Angstron Materials Group and Taiwan Graphene Company. Angstron Materials is involved in producing graphene intermediates and thermal interface materials. Taiwan Graphene Company produces graphene oxide and graphene powder.

The third branch of the corporate structure of G3 involves the company’s energy storage interests. This includes two companies: Honeycomb Battery Company and Angstron Energy Company. Angstron Energy produces both a high-energy silicon anode and a graphene-enabled cathode. Honeycomb Battery is focused on producing lithium-sulfur batteries, non-flammable electrolytes and next-generation lithium battery technologies.

G3 recently became a member of The Graphene Council and we took the opportunity to talk to the company’s representatives, including Dr. Jang. Here is our discussion.

Q: The Global Graphene Group (G3) has an interesting pedigree, being a holding company for Angstron Materials, Nanotek Instruments and Honeycomb Battery. Could you provide a bit of background of how the company came to be and how the various companies that make it up create an overall strategy for the commercialization of graphene?

A: In order to properly answer this question, we would like to tell a brief story about a 17-year relationship with graphene.

Dr. Bor Jang founded Nanotek Instruments Inc. in 1997 and over the past two decades, researchers at Nanotek have developed a broad array of nanomaterials and energy storage and conversion technologies.

A significant accomplishment of Nanotek researchers is the fact that Dr. Jang’s research team discovered/invented graphene in 2002, two years before Drs. A. Geim and K. Novoselov published their first paper on graphene in 2004 [Science 306, 666–669 (October 2004)]. Drs. Geim and Novoselov won the 2010 Nobel Physics Prize for their work on graphene.

There is no doubt that Drs. Geim and Novoselov have made highly significant contributions to graphene science and, as such, well-deserve this Nobel Prize. However, it is important for Graphene Council’s members and associates to recognize that Nanotek researchers had submitted three (3) US patent applications and delivered a lecture on graphene before October 2004 when that milestone paper was published. This fact is evidenced in the following:

  • B. Z. Jang and W. C. Huang, “Nano-scaled Graphene Plates,” US Patent Application No. 10/274,473 (submitted on 10/21/2002); now U.S. Pat. No. 7,071,258 (issued 07/04/2006).
  • B. Z. Jang, et al. “Process for Producing Nano-scaled Graphene Plates,” U.S. Patent Application No. 10/858,814 (06/03/2004).
  • Bor Z. Jang, “Nanocomposite compositions for hydrogen storage and methods for supplying hydrogen to fuel cells,” US Pat. Appl. No. 10/910,521 (08/03/2004); now US Pat. No. 7,186,474 (03/06/2007).
  • W. Schwalm, M. Schwalm, and B. Z. Jang, “Local Density of States for Nanoscale Graphene Fragments,” Am. Phy. Soc. Paper No. C1.157, 03/2004, Montreal, Canada.

(In March 2004, Dr. Jang and his colleagues (Drs. W. Schwalm, M. Schwalm, and J. Wagner) presented a paper at the American Physical Society’s Annual Meeting in Montreal, Canada that discussed the density of state function and related electronic properties of graphene.)

Contrary to the common misconception in the graphene space that the liquid phase exfoliation method was developed in 2008 by a Dublin College team (Hernandez, Y. et al. “High-yield production of graphene by liquid-phase exfoliation of graphite,” Nature Nanotechnology, 3, 563–568 (2008)), Dr. Zhamu/Dr. Jang’s research team at Nanotek developed this method and filed a patent application in 2007.

This provides an effective way of producing pristine graphene directly from graphite without chemical intercalation or oxidation [A. Zhamu, et al., “Method of Producing Exfoliated Graphite, Flexible Graphite, and Nano-Scaled Graphene Plates,” US Patent Application No. 11/800,728 (05/08/2007); now US Patent No. 7,824,651 (11/02/2010)].

Between 2002 and 2007, the Nanotek teams also developed other important graphene production processes, including chemical oxidation, supercritical fluid exfoliation, and electrochemical exfoliation.

Supported by significant IP on several different graphene production processes and graphene applications in composites, thermal management, supercapacitor, and batteries, etc., Drs. Zhamu and Jang decided to co-found Angstron Materials, Inc. in 2007 to begin to scale-up of selected graphene production processes and certain graphene application products.

Subsequently, after many years of development, prototyping, and mass production efforts and establishment of a vast IP portfolio, we found the timing was right for us to establish several business units for more effective commercialization of vastly different products for different industries.

Taiwan Graphene Company (TGC) was founded in 2015 as a leading producer of single-layer graphene oxide, graphene-based nano-intermediates and non-energy-focused application products. Angstron Energy Company (AEC) was founded in 2015 as producer of lithium battery anode and cathode materials. Honeycomb Battery Company (HBC) was also founded in 2015 as a developer and producer of next-generation safe and long-lasting lithium metal batteries, including quasi-solid state battery, lithium-sulfur battery, and lithium-air battery. Angstron Materials was assigned as a research and development company for development of new processes and products. Nanotek remains as the IP-holding company. As suggested by our investors, we also decided to position all five organizations under one umbrella – Global Graphene Group (G3).

Q: How are you marketing graphene at this point, i.e. are you selling graphene raw materials, master batches, etc.? Or are you developing products that incorporate graphene, specifically for Li-ion batteries? Are there other applications you’re pursuing in addition to energy storage?

A: Our Taiwan Graphene Co. (TGC) is selling graphene in powder and dispersion forms, masterbatches for composites, thermal management products, etc. Angstron Energy Co. (AEC) is selling graphene-enabled Si anode materials and graphene-enhanced cathode materials for the lithium-ion battery industry. Honeycomb Battery Company (HBC) is poised to commercialize lithium metal protection technology, non-flammable electrolytes, graphene-enabled sulfur and selenium cathodes, and graphene-enhanced current collectors for next-generation lithium batteries.

Q: What production methods do you use to make your graphene? How has this production avenue determined the applications for your material?

A: We use a combination of improved chemical oxidation process, liquid phase exfoliation, and other proprietary processes, which G3 invented. We have found that different applications require the use of different graphene types produced by different processes.

Q: What have you discovered to be the biggest challenges for your commercialization of graphene and how have you overcome them?

A: We see the greatest challenge to commercialization that it takes time to qualify the application of graphene into various products. We have relationships with several large OEMs in different markets working with our graphene. It just takes time to go through the qualification process.

Q: What direction do you see for the company in the future? Do you see the company moving further up the value chain to the point where all your graphene production is used internally?

A: The future is to grow. We’re targeting to reach $600m+ in annual sales within the next five years between the combination of products in our value chain and graphene raw materials.

Q: What do you think we can expect in the commercialization of graphene over the next 5 to 10 years?

A: Several major applications (so-called killer applications) of graphene are expected to emerge soon. We will see exponential growth as customers integrate graphene into their products to a point where large expansions of graphene manufacturing are necessary. The challenge will be keeping up with the demand.

Tags:  batteries  discovery  graphene  Nobel Prize 

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Haydale graphene-enhanced composite tooling and automotive body panels

Posted By Graphene Council, The Graphene Council, Wednesday, July 17, 2019

Haydale announces that its graphene-enhanced prepreg has now been incorporated in the composite tooling and automotive body panels of the new 'BAC Mono R', which made its debut at Goodwood Festival of Speed.


Briggs Automotive Company (BAC), working alongside both Haydale and Pentaxia, has built the lightweight BAC Mono R body using Haydale’s graphene-enhanced carbon composite materials.

The component parts have been formed using Haydale’s graphene-enhanced tooling materials. The outcome of the process for manufacturing the body parts is a full visual carbon material which can be lacquered or painted as required. Utilisation of graphene-enhanced tooling materials offers the potential for significant improvements in the following aspects:

  • The coefficient of thermal expansion (CTE) – is more closely matched when using composite tooling. A key issue with the use of metal tooling is a significant mismatch in (CTE)
  • The need for superior quality – higher dimensional stability tooling is increasing the demand for composite tooling
  • Current composite tools also suffer from a finite life - wearing of the tool surfaces and microcracking. The use of graphene has the potential to increase the life of the tools

Keith Broadbent, CEO at Haydale, commented: “In the development of this project, Haydale has improved the supply chain and cycle times as well as enabling BAC to reduce weight and increase performance of the material. Whilst this outcome has focused on the automotive sector, the knowledge and improvements made provide a wider opportunity for tooling materials across several markets, particularly where there are throughput constraints.”

Ian Briggs, Design Director at Briggs Automotive Company, added:

“BAC is forever an innovator, and being able to release a new car fully incorporating the use of graphene is just another example of how we’re pushing the boundaries. Niche vehicle manufacturers are of paramount importance in the automotive industry, acting as stepping stones for mass-market production technology – and after the overwhelming success of our R&D project with Haydale and Pentaxia, Mono R could well be a stepping stone for graphene-enhanced composite body panels and tooling reaching the wider automotive industry in the near future.”

Tags:  Briggs Automotive Company  Graphene  Haydale  Ian Briggs  Keith Broadbent 

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Laser-induced graphene composites are eminently wearable

Posted By Graphene Council, The Graphene Council, Monday, June 24, 2019
Graphene has a unique combination of properties that is ideal for next-generation electronics, including mechanical flexibility, high electrical conductivity, and chemical stability. The burgeoning field of wearable electronics – 'smart' fabrics with invisibly integrated energy harvesting, energy storage, electronics and sensor systems – benefits from graphene in numerous ways. Graphene materials, be they pristine or composites, will lead to smaller high-capacity and fast-charging supercapacitors, completely flexible and even rollable electronics and energy-storage devices, and transparent batteries.

To realize the commercial potential of graphene, it is necessary to develop reliable, cost-effective and facile processes for the industry-scale fabrication of graphene-based devices.

One possible route is inkjet printing, already extensively demonstrated with conductive metal nanoparticle inks. Although liquid-phase graphene dispersions have been demonstrated, researchers are still struggling with sophisticated inkjet printing technologies that allow efficient and reliable mass production of high-quality graphene patterns for practical applications.

A novel solution comes from the team at Joseph Wang's Laboratory for Nanobioelectronics at UC San Diego. Reporting their findings in Advanced Materials Technologies ("Laser-Induced Graphene Composites for Printed, Stretchable, and Wearable Electronics"), they demonstrate the synthesis of high-performance stretchable graphene ink using a facile, scalable, and low-cost laser induction method for the synthesis of the graphene component.

As a proof-of-concept, the researchers fabricated a stretchable micro-supercapacitor (S-MSC) demonstrating the highest capacitance reported for a graphene-based highly stretchable MSC to date. This also is the first example of using laser-induced graphene in the form for a powder preparation of graphene-based inks and subsequently for use in screen-printing of S-MSC.

Back in 2014, researchers at Rice University created flexible, patterned sheets of multilayer graphene from a cheap polymer by burning it with a computer-controlled laser, a technique they called laser-induced graphene (LIG). This high-yield and low-cost graphene synthesis process works in air at room temperature and eliminates the need for hot furnaces and controlled environments, and it makes graphene that is suitable for electronics or energy storage.

"LIG can be prepared from a few polymeric substances, such as Kapton polyimide and polyetherimide, as well as various sustainable biomasses, including wood, lignin, cloth, paper, or hydrothermal carbons," Farshad Tehrani, the paper's first author. "On the other hand, LIG has considerably enhanced dispersion in typical solvent and binders due to its inherently abundant defects and surface functional groups."

He points out that the team's novel method, while maintaining the distinct advantages of the direct-written LIG, unlocks untapped potentials of the LIG material in several areas:

Mechanical stretchability: In this study, the inherently brittle and mechanically fragile LIG electrodes are turned into a mechanically robust, highly stretchable electrodes, with the new ink attractive for diverse wearable electronic devices.

Enhanced electrochemical performance: The areal capacitance of the team's S-MSC has far surpassed that of direct-written laser LIG and has produced the highest areal capacitance reported for highly stretchable supercapacitors.

Customized composite formulations: The basic ink formulation is compatible with a wide range of compositions using the LIG as an attractive conductive filler.

Substrate versatility: Unlike direct-laser writing, which is limited to polymeric substrates and several biomasses, the LIG ink can be printed on almost any stretchable and non stretchable substrate, such as polymeric substrates, fabrics, or textiles.

"During the development of our new supercapacitor, we discovered a specific synergic effect between polymeric binders poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) mixed with Polyurethane (PU), PEDOT:PSS-PU and graphene sheets in producing exceptional electromechanical performances," adds Fernando Soto, a co-author of the paper. "We realized that when both sides of the graphene sheets are thoroughly covered with the conductive/elastic PEDOT:PSS/PU polymer, it results in a robust composite that withstands severe shear stresses during stretching."

"Not only that, but it also maintains above 85% of its electrochemical performance such as its charge storing capacitance properties, composite conductivity and electrochemical stability at high charge-discharge cycles," he adds.

In developing wearable electronic devices, researchers need to deal with a range of issues where stretchability and mechanical performance of the device is as important as its electronic properties such as conductivity, charge storage properties and, generally, its high electrochemical performance.

Rather than focusing on one of these specific problems, the team's work addresses a series of challenges that include high mechanical and electrochemical performance while keeping the costs at their lowest possible point for realistic commercialization scenarios.

"From the design to the implementation stages of our study, the primary focus has been devoted to scalability, versatility and cost efficiency of a high performance platform that can potentially spark further innovations using nanocomposite materials in the field of wearable electronics," notes Tehrani.

The next stages of the team's work in this area of wearable applications will see the integration of these high-performance S-MSCs with batteries and energy harvesting systems such as biofuel cells, triboelectrics, and piezoelectrics.

Tags:  Farshad Tehrani  Graphene  Joseph Wang  nanocomposites  nanoelectronics  Sensors  UC San Diego 

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Operational Update on Commercial Graphene Facility

Posted By Graphene Council, The Graphene Council, Tuesday, June 18, 2019
Updated: Saturday, June 15, 2019

NanoXplore Inc. has recently provided an operational update on its new 10,000 metric ton/year commercial graphene facility in Ville St-Laurent (Montréal), Québec, including:

- New Graphene Facility Construction Project Update;
- Capital Expenditures (“CapEx”) Update;
- Operating Expenditures (“Opex”) Update; and
- Graphene Sales Update.

Mr. Rocco Marinaccio, Chief Operational Officer of NanoXplore, commented:

“We are delighted to report on the Corporation’s first significant operational steps in solidifying the commercialization of graphene. The operations team has been working diligently to ensure that the project remains on time and within budget. I am happy to announce that we have achieved this goal to date.

We are now fully engaged and focused on the project’s execution that will further demonstrate that our technology is scalable and economically viable in comparison to other carbon-based additives. As originally scheduled, we plan to commission the new facility at the end of this calendar year and execute our Phase One objective (4,000 metric tons/year) by calendar Q1, 2020”.

New Graphene Facility Construction Project Update  

NanoXplore’s new graphene production facility (located at 4500 Thimens Blvd, Ville St-Laurent, Montréal, Québec) will be housed within an existing 70,000 square foot building. The Corporation has ordered all major long lead time equipment for Phase One (4,000 metric tons/year) development with expected delivery scheduled for the end of calendar Q4 of this year.

All main equipment is being manufactured in America and Europe by reputable companies and all engineering related to these purchases has been completed. No further major equipment purchases will be needed. The detailed engineering related to electrical and mechanical for the major equipment has been completed and remains on-going for other components within the facility. The procurement has been completed for all major equipment and NanoXplore has awarded contracts for the construction and automation of the new facility. The new graphene plant will be a fully automated production plant that will enable a connected and flexible manufacturing system. 

CapEx Update 


NanoXplore anticipates CapEx (capital expenditure) to be 10% less than originally estimated. The overall development for Phase One (4,000 metric tons/year) of the new facility is expected to be on time and under the original planned budget. More specifically, the construction process has already commenced, as indicated above, installation and commissioning of the new plant is expected to begin during calendar Q4 of this year and all primary costs have been contracted and accounted for. The Corporation expects Phase One (4,000 metric tons/year), of a two-phase 10,000 metric tons/year production project, to be fully operational during calendar Q1 of 2020.   

Opex Update

NanoXplore’s Operations team has been working diligently to ensure that continual improvements are implemented during the facility’s project development. The new graphene facility layout has been finalized and fully optimized. This optimization will allow the Corporation to add an additional graphene production line without the need of expanding the new facility as originally contemplated. Furthermore, significant developments in manufacturing efficiencies have bolstered single line graphene production output from 2,000 metric tons/year to 4,000 metric tons/year, doubling single line production capacity. This improvement was a result of a vigorous twelve-month R&D and engineering project that has been successfully tested and implemented at the Corporation’s current production facility. These results were further validated through additional testing on the new facility’s equipment at the suppliers’ locations in the US and in Canada.  

The Operations team has also made significant improvements towards reducing the Corporation’s input costs to produce graphene. We are now able to produce high-quality graphene using small natural flake graphite (-150 mesh). Small natural flake graphite is substantially cheaper than large flake graphite (+80 mesh). Large flake graphite is the current graphite of choice for the Lithium Ion battery market. NanoXplore’s ability to move away from larger flake higher demand will not only dramatically reduce input costs, but will also help the Corporation secure a more readily available graphite supply, significantly reducing future supply risks.

Tags:  Graphene  NanoXplore  Rocco Marinaccio 

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Scientists create ultraviolet light on a graphene surface

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

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

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

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

Dangerous – but useful

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

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

Building on graphene

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

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

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

Let there be light

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

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

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

Use less electricity more cheaply

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

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

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

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AGM signs distribution agreement with CAME srl

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

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

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

Adrian Potts, AGM CEO commented:

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

Verena Cepparulo, CAME Managing Director:

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

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

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How to enlarge 2D materials as single crystals?

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

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


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

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

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

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

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

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

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

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Manipulating atoms one at a time with an electron beam

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

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

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

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

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

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

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

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

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

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

Atomic soccer

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

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

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

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

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

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

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

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

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

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

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

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

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

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Applied Graphene Materials secures patent approval

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

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

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

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

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

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

Tags:  Adrian Potts  Applied Graphene Materials  coatings  Graphene  Paint 

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

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

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

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

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

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

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

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

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

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

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

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

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

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

***

Are you interested in developing graphene enhanced products or applications?

Find a suitable application partner / supplier through The Graphene Council 

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

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UK's National Grid Verifies Viability of Graphene Composite Application

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

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

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

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

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

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

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

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

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

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

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

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Flexible, transparent monolayer graphene device for power generation and storage

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

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

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

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

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

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

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How to purify water with graphene

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Aukam Production Update

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

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

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

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

Tags:  Arno Brand  Battery  Graphene  Graphite  Gratomic 

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Grolltex Ships ‘World’s Smallest Graphene Strain Sensor’ to Large European Partner

Posted By Graphene Council, The Graphene Council, Tuesday, May 14, 2019
Grolltex, has shipped the first version of its patented single atom thick strain sensor to a large European sensor maker partner. The company calls this sensor device, ‘the smallest, most sensitive sensor in the world’ as the base sensing material is only one atom thick and the sensor performance is such that it is capable of measuring the contractive strength of individual heart cells called ‘cardiomyocytes’, providing an important parameter on heart cell health.

“Our strain sensor is very versatile because it is small, flexible, robust and with a gauge factor of up to 1300, it is incredibly sensitive. This means it can be used in a wide variety of applications”, said Jeff Draa, Grolltex CEO. “For example, it can be layered into the skins of airplanes to sense micro stress in the fuselage or be used as a wearable blood pressure monitor in a skin patch configuration. The prototype we delivered to our European partner was designed to measure any environmental pressure or strain that a silicon microchip might experience while sitting in its packaging. This can be important information for many defense or autonomous vehicle related device designs”.

Grolltex, short for ‘graphene-rolling-technologies’, is the largest commercial producer of single layer or electronics grade graphene in North America. The company is lately focusing more of its efforts on servicing sensor markets in the life science and biology areas and seeing continually more adoption of graphene as a sensing material for such uses as DNA sequencing and new drug discovery. Monolayer graphene films are today seen as the most promising futuristic sensing materials for their combination of surface to volume ratio (the film is only one atom thick) and its conductivity (the most conductive substance known at room temperature). 

“For advanced sensor makers that operate at the nano-scale, there is no better material to design your device with than single layer graphene”, said Draa. “The applications and devices that our customers are designing with this material are enabling many previously unobtainable measurements and single layer graphene is now available and affordable for industrialization”. Grolltex makes the raw materials for nano-sensing as well as designing specific sensor devices and packaging for many critical, next generation applications. “We are seeing an explosion of activity in the micro-sensing world as sensor makers are picking up on the versatility and measurement performance benefits of this single atom thick material”.

Tags:  Graphene  Grolltex  Jeff Draa  Nanosensors  sensors 

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Join the Graphene Flagship Core 3 Project

Posted By Graphene Council, The Graphene Council, Friday, May 10, 2019



The Graphene Flagship is looking for new partners to bring specific industrial and technology transfer competences or capabilities that complement the present consortium in the next core project. 

We are seeking partners with the following expertise:

  • MRAM tools developer to leverage solutions for GRM-spintronic stacks
  • Exposure and risk assessment of GRMs for occupational health
  • Clinical translation of GRM-based therapeutic medical devices for the central nervous system
  • Component manufacturer for GRM-based networking devices and interconnects 
  • Developer of GRM-based laser systems and instrumentation for coherent Raman imaging
  • Manufacturing and modification of GRM-based fibres, yarns and textiles
  • Automotive company with expertise in development of fuel cells for cars
  • Industrial GRM-based supercapacitors manufacturer
  • Manufacturer of GRM-based anticorrosion coatings
  • Developer of GRM-based pressure sensors for health monitoring in automotive applications
  • Manufacturer to deliver a ready-to-reach-the-market sports car with enhanced functionalities based on GRM/Carbon Fibre Reinforced Polymer composites
  • GRM-based composites manufacturer
  • Preparation of large GRM-based multifunctional pipes by filament winding
  • Formulation of low viscosity epoxy resins incorporating GRMs for aerostructures manufactured by infusion technologies


The selected new partners will be incorporated in the scientific and technological Work Packages of the third Core Project under the Horizon 2020 phase of the Graphene Flagship that will run during 1 April 2020 – 31 March 2023.

The addition of new partners to the Graphene Flagship consortium is subject to the approval of the required contract amendment by the Graphene Flagship General Assembly and, at a later stage, the European Commission.

Tags:  Graphene  Graphene Flagship 

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Graphene sponge helps lithium sulphur batteries reach new potential

Posted By Graphene Council, The Graphene Council, Friday, May 3, 2019
Updated: Wednesday, May 1, 2019
To meet the demands of an electric future, new battery technologies will be essential. One option is lithium sulphur batteries, which offer a theoretical energy density more than five times that of lithium ion batteries. Researchers at Chalmers University of Technology, Sweden, recently unveiled a promising breakthrough for this type of battery, using a catholyte with the help of a graphene sponge.

The researchers' novel idea is a porous, sponge-like aerogel, made of reduced graphene oxide, that acts as a free-standing electrode in the battery cell and allows for better and higher utilisation of sulphur.

A traditional battery consists of four parts. First, there are two supporting electrodes coated with an active substance, which are known as an anode and a cathode. In between them is an electrolyte, generally a liquid, allowing ions to be transferred back and forth. The fourth component is a separator, which acts as a physical barrier, preventing contact between the two electrodes whilst still allowing the transfer of ions.

The researchers previously experimented with combining the cathode and electrolyte into one liquid, a so-called 'catholyte'. The concept can help save weight in the battery, as well as offer faster charging and better power capabilities. Now, with the development of the graphene aerogel, the concept has proved viable, offering some very promising results.

Taking a standard coin cell battery case, the researchers first insert a thin layer of the porous graphene aerogel.

"You take the aerogel, which is a long thin cylinder, and then you slice it - almost like a salami. You take that slice, and compress it, to fit into the battery," says Carmen Cavallo of the Department of Physics at Chalmers, and lead researcher on the study. Then, a sulphur-rich solution - the catholyte - is added to the battery. The highly porous aerogel acts as the support, soaking up the solution like a sponge.

"The porous structure of the graphene aerogel is key. It soaks up a high amount of the catholyte, giving you high enough sulphur loading to make the catholyte concept worthwhile. This kind of semi-liquid catholyte is really essential here. It allows the sulphur to cycle back and forth without any losses. It is not lost through dissolution - because it is already dissolved into the catholyte solution," says Carmen Cavallo.

Some of the catholyte solution is applied to the separator as well, in order for it to fulfil its electrolyte role. This also maximises the sulphur content of the battery.

Most batteries currently in use, in everything from mobile phones to electric cars, are lithium-ion batteries. But this type of battery is nearing its limits, so new chemistries are becoming essential for applications with higher power requirements. Lithium sulphur batteries offer several advantages, including much higher energy density. The best lithium ion batteries currently on the market operate at about 300 watt-hours per kg, with a theoretical maximum of around 350. Lithium sulphur batteries meanwhile, have a theoretical energy density of around 1000-1500 watt-hours per kg.

"Furthermore, sulphur is cheap, highly abundant, and much more environmentally friendly. Lithium sulphur batteries also have the advantage of not needing to contain any environmentally harmful fluorine, as is commonly found in lithium ion batteries," says Aleksandar Matic, Professor at Chalmers Department of Physics, who leads the research group behind the paper.

The problem with lithium sulphur batteries so far has been their instability, and consequent low cycle life. Current versions degenerate fast and have a limited life span with an impractically low number of cycles. But in testing of their new prototype, the Chalmers researchers demonstrated an 85% capacity retention after 350 cycles.

The new design avoids the two main problems with degradation of lithium sulphur batteries - one, that the sulphur dissolves into the electrolyte and is lost, and two, a 'shuttling effect', whereby sulphur molecules migrate from the cathode to the anode. In this design, these undesirable issues can be drastically reduced.

Tags:  Aleksandar Matic  Battery  Carmen Cavallo  Chalmers University of Technology  Graphene  Li-ion Batteries  Lithium 

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Decoupled graphene thanks to potassium bromide

Posted By Graphene Council, The Graphene Council, Friday, May 3, 2019
Updated: Wednesday, May 1, 2019

The use of potassium bromide in the production of graphene on a copper surface can lead to better results. When potassium bromide molecules arrange themselves between graphene and copper, it results in electronic decoupling. This alters the electrical properties of the graphene produced, bringing them closer to pure graphene, as reported by physicists from the universities of Basel, Modena and Munich in the journal ACS Nano.

Graphene consists of a layer of carbon atoms just one atom in thickness in a honeycomb pattern and is the subject of intensive worldwide research. Thanks to its high level of flexibility, combined with excellent stability and electrical conductivity, graphene has numerous promising applications – particularly in electronic components.

Molecules for decoupling

Mono-Layer Graphene is often produced via a chemical reaction on metallic surfaces in a process known as chemical vapor deposition. The graphene layer and the underlying metal are then electrically coupled, which diminishes some of the special electrical properties of graphene. For use in electronics, the graphene has to be transferred onto insulating substrates in a multistep process, during which there is a risk of damage and contamination.

In order to obtain defect-free, pure graphene, it is therefore preferable to decouple the graphene electrically from the metallic substrate and to develop a method that allows easier transfer without damage. The group led by Professor Ernst Meyer from the Department of Physics and the Swiss Nanoscience Institute (SNI) of the University of Basel is investigating ways of incorporating molecules between the graphene layer and the substrate after the chemical deposition process, which leads to this type of decoupling.

Altering electrical properties

In a study carried out by SNI doctoral student Mathias Schulzendorf, scientists have shown that potassium bromide is ideally suited to this. Potassium bromide is a soluble hydrogen bromide salt. Unlike the chemically similar compound sodium chloride, potassium bromide molecules arrange themselves between the graphene layer and the copper substrate. This was demonstrated by researchers in a variety of scanning probe microscopy studies.

Calculations performed by colleagues at the University of Modena and Reggio Emilia (Italy) explain this phenomenon: It is more energetically advantageous for the system if potassium bromide molecules arrange themselves between the graphene and copper than if they are deposited on the graphene – as happens with sodium chloride.

The researchers have shown that the intermediate layer of potassium bromide alters the electrical properties of graphene – until they correspond to those expected for free graphene. “Our work has demonstrated that the graphene and the underlying metal can be decoupled using potassium bromide, bringing us a key step closer to producing clean and defect-free graphene,” says project supervisor Dr. Thilo Glatzel, who is a member of Meyer’s team.

Tags:  Ernst Meyer  Graphene  Thilo Glatzel  Universities of Basel. Swiss Nanoscience Institute 

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New graphene-based material developed for medical implants

Posted By Graphene Council, The Graphene Council, Thursday, May 2, 2019
Updated: Wednesday, May 1, 2019
A group of scientists have developed a new material for biomedical applications by combining a graphene-based nanomaterial with Hydroxyapatite (HAp), a commonly used bioceramic in implants.

In recent years, biometallic implants have become popular as a means to repair, restructure or replace damaged or diseased parts in orthopaedic and dental procedures. Metal parts also find use in devices such as pacemakers.

However, metallic implants face several limitations and are not a permanent solution. They react with body fluids and corrode, release wear and tear debris resulting in toxins and inflammation. They also have high thermal expansion and low compressive strength causing pain and are dense and may cause reactions.

On the other hand, bioceramics do not have these limitations. HAp specifically is osteoconductive, with a bone-like porous structure offering the required scaffold for tissue re-growth. However, it is brittle and lacks the mechanical strength of metals. The problem is overcome by combining it with nanoparticles of materials such as Zirconia.

In the new research, scientists have combined HAp with graphene nanoplatelets. “Previously reported studies have focused on only structural properties of such composites without throwing light on their biological properties. We have found that combining HAp with graphene nanomaterial enhances mechanical strength, provides better in-vivo imaging and biocompatibility without changing its basic bone-like properties,” explained Dr Gautam Chandkiram, the principal investigator at University of Lucknow, while speaking to India Science Wire.

Purification of the base ceramic material is a significant primary challenge in fabricating composites. According to scientists, in the current study, highly efficient biocompatible Hydroxyapatite was successfully prepared via a microwave irradiation technique and the consequent composites was synthesised using a simple solid-state reaction method.

The process involved mixing different concentrations of graphene nanoplatelet powders and drying, crushing, sieving and ball-milling the resulting slurry. The fine composite powder was further cold-compressed and sintered at 1200 degrees Celsius to achieve the desired density.

The scientists found that the composite had adequate interfacial area between the nanoparticles, with the graphene nanoplatelets well distributed into the hydroxyapatite matrix, while exhibiting high fracture resistance. Further, structural characterization, mechanical and load bearing tests showed that the 2D nature of graphene improves the load transfer efficiency significantly.

Researchers also examined cell viability of the composite by observing metabolic activity in specific cells using a procedure known as MTT assay. They used gut tissues of Drosophila larvae and primary osteoblast cells of a rat. “The overall cell viability studies demonstrated that there is no cytotoxic effect of the composites on any cell type,” explained Dr. Gautam.

Biomaterials also find use in drug delivery and bioimaging diagnosis. “Our research on the composite found that it displays a better fluorescence behaviour as compared to pure hydroxyapatite, indicating it has a great potential in bone engineering and bioimaging bio-imaging applications as well,” he added.

Tags:  2D Materials  Gautam Chandkiram  Graphene  Medical  nanomaterials  University of Lucknow 

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Thomas Swan Advanced Materials announce exciting Graphene collaboration with Graphene Composites Ltd pioneering advanced protection against knife and gun-crime

Posted By Graphene Council, The Graphene Council, Wednesday, May 1, 2019
Thomas Swan is proud to collaborate with nano-materials technology manufacturer Graphene Composites Ltd to provide the graphene solution in their GC Shield™ armour products. The product is the result of a lengthy development collaboration between the companies together with the Centre for Process Innovation (CPI) using GNP-M grade graphene from Thomas Swan in the final application - an endorsement of the company’s ability to manufacture graphene in volume.

The GC Shield™ comes in a range of armour products providing lightweight, mobile protection to individuals and groups, plus effective protection for installation in large spaces. From a lightweight, flexible shield that is both bullet and stab-proof and can fit into a schoolbag, the GC Shield™ Plus has been successfully tested to stop multiple 7.62 x 51mm NATO M80 sniper bullets and AR-15 assault rifle M193 bullets fired at close range. The GC Shield™ Curtain can be deployed quickly, effectively and safely to provide protection in large spaces (e.g. school cafeterias, open plan areas, entrance halls).

Michael Edwards, head of the Advanced Materials Division at Thomas Swan said “It is always great to see an end-application that transfers into production demonstrating real-life applications for graphene – something that has been evasive in our market to date. As always there is a learning curve to be developed with a willing partner for a go-to market product, but we are always delighted to reach that point”.

Thomas Swan has a patented process to produce Multiple Layer (MLG) and Graphene Nanoplatelets (GNP) in volume at our facility in Consett, UK. Using our patented process of HighShear Liquid Phase Exfoliation licensed from Professor Jonathan Coleman’s work at Trinity College Dublin, we have further enhanced the process using our expertise at Thomas Swan, scaling-up to a 20T per year GNP capacity available today. We have the distinct advantage of being an established global player in the chemicals and materials business.

With manufacturing in the UK, a subsidiary company in the USA together with QA, logistics, regulatory and safety management, we are a leader in the field of 2D materials. Sandy Chen, CEO and founder of Graphene Composites said “Thomas Swan’s expertise in graphene manufacturing has been crucial to our success in developing our revolutionary armour products. Not only has the high quality and consistent manufacture made this possible but as a company, their willingness to collaborate closely with our Technical Team in our development processes has led to innovative and agile product design and development. This has enabled us to get our products market-ready much more quickly”.

Tags:  2D materials  Graphene  Graphene Composites  Jonathan Coleman  Michael Edwards  nanomaterials  Sandy Chen  Thomas Swan 

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Future Surrey research stars backed with grants totaling £1 million by EPSRC

Posted By Graphene Council, The Graphene Council, Tuesday, April 30, 2019
Updated: Friday, April 26, 2019

Surrey University has recently seen four successful New Investigator Award applications - including projects that look at new techniques to better understand the movements of plastics in our oceans, an investigation into the next generation of dental materials, a project looking to develop a game-changing carbon capture material and security protocols for future communications networks.

Predicting the fate of our plastics

Dr Thomas Bond, Lecturer from Surrey’s Department of Civil and Environmental Engineering, was granted over £260,000 to develop his research that will better predict the location of plastic litter in the environment. It is not known where 99 percent of the ocean’s plastic litter is, making it difficult to deal with this catastrophic environmental problem. Dr Bond will be looking at how different commonly used plastics behave and he will be using several experimental tests to develop methods that predict the fate of plastics polluting our waters.

Dr Bond said: “The amount of plastic litter in the environment is growing rapidly. Its presence poses a severe threat to marine and freshwater life. However, at the heart of our knowledge of plastic litter lies a black hole. I hope this project will give us a clearer picture of what happens to plastic waste in the environment. We will also investigate whether promoting sustainable types of plastics may obviate the problem of plastic litter in the environment.”

Next generation of dental material

Dr Tan Sui, Lecturer in Materials Engineering from the Department of Mechanical Engineering Sciences, was given just over £250,000 to investigate the next generation of dental materials that could be key to improving oral restorative surgeries. Together with the Universities of Bristol and Birmingham, the National Physical Laboratory and the Agency for Science, Technology and Research, Dr Sui will look to create a material that acts and performs like natural dental materials, with improved longevity.

Dr Tan Sui said: “Thanks to the advances of science and medicine we are all living longer but, unfortunately, our teeth are not faring so well. We hope this project will give us a deep understanding of novel dental materials, especially zirconia-based composites, with bioinspired functionally graded and textured microstructures -- and of how through refinement they may be durable enough to become the optimal dental restorative products.”

Carbon capture

Dr Marco Sacchi, Royal Society University Research Fellow, was awarded £230,000 to develop a computational research project that will reduce the cost and increase the efficiency of materials for carbon capture. In his project, Dr Sacchi will use Graphene, a newly discovered “miracle” material that has promising physical and thermal properties. The project will see Dr Sacchi join forces with a multidisciplinary team of chemists, nanotechnologists and physicists in industry and academia to test Graphene’s scientific boundaries and whether it can be used to entrap and treat greenhouse gases.

Dr Sacchi said: “Climate change is the biggest challenge that faces our planet today. It is an incredibly complex problem that requires teamwork from across the scientific spectrum to find sustainable solutions. We believe that by combining theoretical modelling with experimental validation, material testing and applied catalysis we will be able test the boundaries of Graphene and maximise its societal impact.”

Cybersecurity

Dr Ioana Boureanu, Lecturer in the Department of Computer Science and Surrey Centre for Cyber Security, was awarded just under £300,000 for the Automatic Verification of Complex Privacy Requirements in Unbounded-Size Secure Systems (AutoPaSS) project. AutoPaSS will develop formal methods and software-tools needed to analyse security and, especially, privacy in modern communications systems. AutoPaSS is in collaboration with industrial partners Thales and Vector GB Ltd.

Dr Boureanu said: “Today's devices execute concurrently in numerous and hyper-connected ways. So, we need reliable system-analysis techniques that capture not only cybersecurity properties but also modern connectivity. Importantly, this becomes an even bigger challenge if one needs to faithfully analyse rich privacy properties, such as anonymity and users’ untraceability. AutoPaSS will address this gap in the formal verification of 2020s' secure systems such as those driven by Internet of Things and connected, smart cars.”

Professor David Sampson, Vice-Provost, Research and Innovation, said: “These fantastic projects show that the University of Surrey is generating a wealth of bold, novel and innovative research ideas that have the potential to change everyday lives and the health of the planet. I want to congratulate our up-and-coming academics on their first steps into leading a research project. As a University, we are committed to supporting them and we wish them every success in these first steps towards an independent research career.”

Tags:  David Sampson  Engineering and Physical Sciences Research Council  Graphene  Ioana Boureanu  Marco Sacchi  Plastics  Tan Sui  Thomas Bond  University of Surrey 

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New Technique Produces Longer-lasting Lithium Batteries

Posted By Graphene Council, The Graphene Council, Monday, April 29, 2019
Updated: Friday, April 26, 2019
The grand challenge to improve energy storage and increase battery life, while ensuring safe operation, is becoming evermore critical as we become increasingly reliant on this energy source for everything from portable devices to electric vehicles. A Columbia Engineering team led by Yuan Yang, assistant professor of materials science and engineering, announced that they have developed a new method for safely prolonging battery life by inserting a nano-coating of boron nitride (BN) to stabilize solid electrolytes in lithium metal batteries. Their findings are outlined in a new study published by Joule.

While conventional lithium ion (Li-ion) batteries are currently widely used in daily life, they have low energy density, resulting in shorter battery life, and, because of the highly flammable liquid electrolyte inside them, they can short out and even catch fire. Energy density could be improved by using lithium metal to replace the graphite anode used in Li-ion batteries: lithium metal’s theoretical capacity for the amount of charge it can deliver is almost 10 times higher than that of graphite. But during lithium plating, dendrites often form and, if they penetrate the membrane separator in the middle of the battery, they can create short-circuits, raising concerns about battery safety.

“We decided to focus on solid, ceramic electrolytes. They show great promise in improving both safety and energy density, as compared with conventional, flammable electrolytes in Li-ion batteries,” says Yang. “We are particularly interested in rechargeable solid-state lithium batteries because they are promising candidates for next-generation energy storage.”

Most solid electrolytes are ceramic, and therefore non-flammable, eliminating safety concerns. In addition, solid ceramic electrolytes have a high mechanical strength that can actually suppress lithium dendrite growth, making lithium metal a coating option for battery anodes. However, most solid electrolytes are unstable against Li—they can be easily corroded by lithium metal and cannot be used in batteries.

“Lithium metal is indispensable for enhancing energy density and so it’s critical that we be able to use it as the anode for solid electrolytes,” says Qian Cheng, the paper’s lead author and a postdoctoral research scientist in the department of applied physics and applied mathematics who works in Yang's group. “To adapt these unstable solid electrolytes for real-life applications, we needed to develop a chemically and mechanically stable interface to protect these solid electrolytes against the lithium anode. It is essential that the interface not only be highly electronically insulating, but also ionically conducting in order to transport lithium ions. Plus, this interface has to be super-thin to avoid lowering the energy density of batteries.”

To address these challenges, the team worked with colleagues at Brookhaven National Lab and the City University of New York. They deposited 5~10 nm boron nitride (BN) nano-film as a protective layer to isolate the electrical contact between lithium metal and the ionic conductor (the solid electrolyte), along with a trace quantity of polymer or liquid electrolyte to infiltrate the electrode/electrolyte interface. They selected BN as a protective layer because it is chemically and mechanically stable with lithium metal, providing a high degree of electronic insulation. They designed the BN layer to have intrinsic defects, through which lithium ions can pass through, allowing it to serve as an excellent separator. In addition, BN can be readily prepared by chemical vapor deposition to form large-scale (~dm level), atomically thin scale (~nm level), and continuous films.

“While earlier studies used polymeric protection layers as thick as 200 µm, our BN protective film, at only 5~10 nm thick, is record-thin—at the limit of such protection layers—without lowering the energy density of batteries,” Cheng says. “It’s the perfect material to function as a barrier that prevents the invasion of lithium metal to solid electrolyte. Like a bullet-proof vest, we’ve developed a lithium-metal-proof ‘vest’ for unstable solid electrolytes and, with that innovation, achieved long-cycling lifetime lithium metal batteries.”

The researchers are now extending their method to a broad range of unstable solid electrolytes and further optimizing the interface. They expect to fabricate solid-state batteries with high performance and long-cycle lifetimes.
 

Tags:  Batteries  Boron Nitride  Columbia Engineering  Graphene  Li-Ion batteries  Qian Cheng  Yuan Yang 

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Modified 'white graphene' for eco-friendly energy

Posted By Graphene Council, The Graphene Council, Wednesday, April 24, 2019
Updated: Tuesday, April 23, 2019
Scientists from TPU, Germany, and the United States have found a new way to functionalize a dielectric, otherwise known as 'white graphene', i.e. hexagonal boron nitride (hBN), without destroying it or changing its properties. Thanks to the new method, the researchers synthesized a 'polymer nano carpet' with strong covalent bond on the samples.

Prof Raul Rodriguez from the TPU Research School of Chemistry & Applied Biomedical Sciences explains:

'For the first time, we have managed to covalently functionalize hexagonal boron nitride without strong chemical compositions and the introduction of new defects into the material. In fact, earlier approaches had resulted in a different material with altered properties, i.e. hydrolyzed boron nitride. In our turn, we used nanodefects existing in the material without increasing their number, and eco-friendly photopolymerization.'

One of the promising options for using the new material, according to researchers, is catalysts for splitting water in hydrogen and oxygen. With this in view, 'polymer carpets' functioned as carriers of active substances, i.e. matrices. Nickel nanoparticles were integrated into the matrix. Catalysts obtained were used for electrocatalysis. Studies showed that they could be successfully used as an alternative to expensive platinum or gold.

'One of the important challenges in catalysis is forcing the starting material to reach active centers of the catalyst. 'Polymer carpets' form a 3D structure that helps to increase the area of contact of the active centers of the catalyst with water and makes hydrogen acquisition more efficient. It is very promising for the production of environmentally friendly hydrogen fuel,' - says the scientist.

Boron nitride is a binary compound of boron and nitrogen. While, hexagonal boron nitride or 'white graphene' is a white talc-like powder with hexagonal, graphene-like lattice. It is resistant to high temperatures and chemical substances, nontoxic, has a very low coefficient of friction, and functions both as a perfect dielectric and as a good heat conductor. Boron-nitride materials are widely used in the reactions of industrial organic synthesis, in the cracking of oil, for the manufacturing of products of high-temperature technology, the production of semiconductors, means for extinguishing fires, and so on.

Previously, a number of studies were devoted to functionalization of hexagonal boron nitride. Typically, this process uses strong chemical oxidants that not only destroy the material but also significantly change its properties. The method, which TPU scientists and their foreign colleagues use, allows them to avoid this.

'Studies have shown that we obtained homogenous and durable 'polymer carpets' which can be removed from the supporting substrate and used separately. What is more, this is a fairly universal technology since for functionalization we used different monomers which allow obtaining materials with properties optimal for use in various devices,' - says Prof Raul Rodriguez.

Tags:  2D materials  Graphene  Hexagonal Boron Nitride  Raul Rodriguez  TPU Germany 

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