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Gratomic Provides Update to Shareholders

Posted By Graphene Council, Tuesday, February 25, 2020
Gratomic Inc is pleased to provide the following update to shareholders on general operations and the issuance of mining license ML215.

Mining License Update


On the 24th of January the Company's Co-CEO, Arnoldus Brand met with the Ministry of Mines and Energy in Namibia to satisfy a request that came from the special committee that is in charge of recommending the mining license request to the Minister of Mines and Energy, to provide an update on mine development and to fulfill certain criteria required for the approval of the mining license.

The Company is happy to report that it fulfilled 100% of the required criteria during the meeting and was requested to amend the current Environmental Impact Assessment and Environmental Management Plan over EPL 3895 to include ML 215.

After meeting with the members of the special committee, the Company immediately engaged Risk-Based Solutions (RBS) CC, Consulting Arm of Foresight Group Namibia (FGN) (Pty) Ltd, to start amending the EIA and EMP to include ML215. The final submission of the amended EIA and EMP was done on the 17th of February 2020. Through this submission Gratomic has now fulfilled all requirements to satisfy the committee's requests and is now waiting to hear back from the Ministry of Mines and Energy with respect to the granting of mining licence ML215.

We would like to thank the Ministry for their co-operation and hard work to help Gratomic advance towards a mining company from a junior exploration company.

Operations Update

The Chinese manufacturing facility that is supplying the last pieces of equipment that make up the greater part of the drying circuit for the Aukam mine graphite processing plant has experienced significant delays due to the impact of the Coronavirus and has been unable to ship the equipment. The Company has been waiting for correspondence from the manufacturer on the platform designs that are required to be poured at the same time as the shipment leaves China to provide a sufficient curing period for the concrete platforms. The minimum shipping time from China to Namibia is 39 days once the equipment leaves port. We foresee further delays at both the port of China and the port of Walvis Bay given strict quarantine restrictions at both ports currently.

On the 19th of February the Company received feed-back from the manufacturer on the platform designs and confirmation that some of the staff have returned back to the factory and it is now able to proceed with shipping of the remaining equipment.

The List of Equipment from China includes the following:

Cyclone Cluster

10 m Electrical Dryer

Thickener

600 mm conveyor belt

Filter press

Slurry pumps and lines

The equipment was specifically designed and built to accommodate mass balance pull and the treatment of Aukam Graphite based on the results of our pilot testing programs.

The remainder of the equipment has already been set up on site and what remains is the arrival of this equipment to fully complete the 20,000 tonnes per year operating capacity of the processing facility.

We appreciate the patience of our shareholders during this delay.

We further sympathize with our Chinese vendors as they have been going through a difficult time.

Management Update

In an effort to reduce the Company's expenditures, the majority of Namibian staff and management has agreed to go to 50% remuneration as per SECTION 12 (6) OF THE NAMIBIAN LABOUR ACT NO 11 OF 2007 until the granting of ML215. The Canadian management team has lead by example by doing the same in an effort to preserve capital for operations.

The efforts by the Namibian team to agree to such conditions is extraordinary and shows their commitment to the success of the business.

We thank each and every one of our devoted and hard-working employees for their commitment towards the success of Gratomic as a company.

Financing Update

Gratomic further pushes to conclude its current financing as the Company moves towards fully commercializing its assets.

To date the Company has raised CAD $626,000 of up to a CAD $2.5 million-dollar issuance.

Management has excelled beyond their calling to do as much as they can to further operations along and will continue to work relentlessly to earn success.

TODA Notes Update


Further to the press release of October 17, 2019, where Gratomic announced the Supply Agreement with TODAQ Holdings ("TODAQ") to supply TODAQ with an aggregate of USD $25,000,000 of graphite, payable in TODA Notes ("TDN"), and the subsequent press release on December 20, 2019 where Gratomic received its first of two purchase orders from TODAQ, Gratomic is pleased to provide an update on the current status of TDN trading. TDN has been trading on BitForex, a digital asset exchange, with a 30-day average price and volume of approximately USD $0.24 and USD $950,000, respectively. TDN first started trading on Bitforex on November 1, 2019 at a price of USD $0.10 and a volume of USD $300,000. To follow TDN, please click the following link: https://www.bitforex.com/en/spot/tdn_btc. No TDN will be issued to the Company until the equipment arrives from China and the processing plant is in production.

Arno Brand, Co-CEO, stated: "These have been trying times for the Company as it progresses its efforts to evolve from a junior exploration company to a mining company. The achievements of those that have sacrificed their time in making it a reality will not go unnoticed. The Company is still in a very strong position as it has built its operations without having to fall on the assistance of an abusive debt transaction that will impede its profitability and damage shareholder value going forward. I am proud of our team for their patience and hard work as we wait for our mining license. I would further like to thank all the shareholders for their continued support."

Risk Factors

No mineral resources, let alone mineral reserves demonstrating economic viability and technical feasibility, have been delineated on the Aukam Property. The Company is not in a position to demonstrate or disclose any capital and/or operating costs that may be associated with satisfying the terms of the TODAQ Supply Agreement.

Gratomic wishes to emphasize that Supply Agreement is conditional on Gratomic being able to bring the Aukam project into a production phase, and for any graphite being produced to meet certain technical and mineralization requirements.

Gratomic continues to move its business towards production and as part of its business plan, expects to obtain a National Instrument 43-101 Standards of Disclosure for Mineral Projects technical report to help it ascertain the economics of Aukam. Presently the Company uses its existing pilot processing facility to produce certain amounts of graphite concentrate from accumulated surface graphite.

The Company advises that it has not based its production decision on even the existence of mineral resources let alone on a feasibility study of mineral reserves, demonstrating economic and technical viability, and, as a result, there may be an increased uncertainty of achieving any particular level of recovery of minerals or the cost of such recovery, including increased risks associated with developing a commercially mineable deposit.

The Supply Agreement provides that if Gratomic is unable to deliver graphite in accordance with the orders from Todaq, Todaq has the right to refuse to take any subsequent attempt to fulfill the order, terminate the agreement immediately, obtain substitute product from another supplier and recover from the Company any costs and expenses incurred in obtaining such substitute product or suing for damages under the contract.

Historically, such projects have a much higher risk of economic and technical failure. There is no guarantee that production will begin as anticipated or at all or that anticipated production costs will be achieved.

Failure to commence production would have a material adverse impact on the Company's ability to generate revenue and cash flow to fund operations. Failure to achieve the anticipated production costs would have a material adverse impact on the Company's cash flow and future profitability.

Steve Gray, P.Geo. has reviewed and approved the scientific and technical information in this press release and is Gratomic's "Qualified Person" as defined by National Instrument 43-101 - Standards of Disclosure for Mineral Projects.

Tags:  Arnoldus Brand  Graphene  Graphite  Gratomic 

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First Graphene signs exclusive supply agreement with Steel Blue

Posted By Graphene Council, Wednesday, February 12, 2020
First Graphene Ltd, the leading global producer of advanced graphene products, has signed an exclusive supply agreement with Steel Blue, a major global manufacturer of work boots. Under the supply agreement, Steel Blue will exclusively source graphene and any other graphite or graphene products from First Graphene over a 2-year term.

First Graphene recently partnered with Steel Blue to develop an effective manufacturing process, with graphene being incorporated successfully into thermoplastic polyurethane masterbatches, used for the production of the soles and other components of safety boots. This work was followed by wear trials and independent product testing by Viclab Pty Ltd, one of Australia’s leading NATA accredited testing facilities. The results showed an increase in abrasion and tensile strength, potentially leading to extended product life, plus enhanced heat transfer and reduction in weight.

First Graphene’s Managing Director, Craig McGuckin, explains that, “The new supply agreement highlights the confidence that Steel Blue has in our PureGRAPH® materials and in our ability to deliver large volumes of graphene over an extended period. PureGRAPH® has the ability to help our customers throughout industry transform the characteristics of existing products and materials. For example, PureGRAPH® additives are a key enabler in taking elastomers, composites, coatings and concrete to new levels of performance and we’re actively working with customers in these sectors. As a result, we anticipate that the supply agreement with Steel Blue will be the first in a growing number to be signed during 2020.”

Chief Executive Officer, at Steel Blue, Garry Johnson, commented, “Steel Blue is committed to developing innovative solutions for our customers. We’re excited by the innovations we have developed with First Graphene. We look forward to bringing exciting new safety technologies to the global work boot market.”

Tags:  Craig McGuckin  First Graphene  Garry Johnson  Graphene  Graphite  Steel Blue  Viclab Pty Ltd 

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'Superdiamond' carbon-boron cages can trap and tap into different properties

Posted By Graphene Council, Monday, January 13, 2020
A long-sought-after class of "superdiamond" carbon-based materials with tunable mechanical and electronic properties was predicted and synthesized by Carnegie's Li Zhu and Timothy Strobel. Their work is published by Science Advances.

Carbon is the fourth-most-abundant element in the universe and is fundamental to life as we know it. It is unrivaled in its ability to form stable structures, both alone and with other elements.

A material's properties are determined by how its atoms are bonded and the structural arrangements that these bonds create. For carbon-based materials, the type of bonding makes the difference between the hardness of diamond, which has three-dimensional "sp3" bonds, and the softness of graphite, which has two-dimensional "sp2" bonds, for example.

Despite the enormous diversity of carbon compounds, only a handful of three-dimensionally, sp3-bonded carbon-based materials are known, including diamond. The three-dimensional bonding structure makes these materials very attractive for many practical applications due to a range of properties including strength, hardness, and thermal conductivity.

"Aside from diamond and some of its analogs that incorporate additional elements, almost no other extended sp3 carbon materials have been created, despite numerous predictions of potentially synthesizable structures with this kind of bonding," Strobel explained. "Following a chemical principle that indicates adding boron into the structure will enhance its stability, we examined another 3D-bonded class of carbon materials called clathrates, which have a lattice structure of cages that trap other types of atoms or molecules."

Clathrates comprised of other elements and molecules are common and have been synthesized or found in nature. However, carbon-based clathrates have not been synthesized until now, despite long-standing predictions of their existence. Researchers attempted to create them for more than 50 years.

Strobel, Zhu, and their team -- Carnegie's Gustav M. Borstad, Hanyu Liu, Piotr A. Guńka, Michael Guerette, Juli-Anna Dolyniuk, Yue Meng, and Ronald Cohen, as well as Eran Greenberg and Vitali Prakapenka from the University of Chicago and Brian L. Chaloux and Albert Epshteyn from the U.S. Naval Research Laboratory -- approached the problem through a combined computational and experimental approach.

"We used advanced structure searching tools to predict the first thermodynamically stable carbon-based clathrate and then synthesized the clathrate structure, which is comprised of carbon-boron cages that trap strontium atoms, under high-pressure and high-temperature conditions," Zhu said.

The result is a 3D, carbon-based framework with diamond-like bonding that is recoverable to ambient conditions. But unlike diamond, the strontium atoms trapped in the cages make the material metallic -- meaning it conducts electricity -- with potential for superconductivity at notably high temperature.

What's more, the properties of the clathrate can change depending on the types of guest atoms within the cages.

"The trapped guest atoms interact strongly with the host cages," Strobel remarked. "Depending on the specific guest atoms present, the clathrate can be tuned from a semiconductor to a superconductor, all while maintaining robust, diamond-like bonds. Given the large number of possible substitutions, we envision an entirely new class of carbon-based materials with highly tunable properties."

"For anyone who is into -- or whose kids are into -- Pokémon, this carbon-based clathrate structure is like the Eevee of materials," joked Zhu. "Depending which element it captures, it has different abilities."

Tags:  2D materials  Carnegie Institution for Science  Electronics  Graphene  Graphite  Li Zhu  Timothy Strobel  University of Chicago 

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Accelerating Graphene’s Commercial Deployment

Posted By Graphene Council, Monday, January 13, 2020
Updated: Friday, January 10, 2020
Guest Editorial from Dr. Francis Nedvidek, Faculty of Science at the Technical University of Dresden

After initial isolation in 2004 and a decade and one-half of follow-on discovery, material research and process development, only a trickle of graphene enhanced applications have reached the market. In spite of huge progress and critical advances the so called “killer applications” have yet to appear. Commercial deployment of nanoplatelet graphene, not to mention a cohort of emerging 2D materials, face three challenges.

The first and most obvious obstacle is a consequence of graphene’s newness. Harnessing novel functionality entails painstaking searches for new recipes, non-standard ingredients and adaptation of processes, manufacturing methods and industrial infrastructure. The second hurdle relates to graphene’s assimilation into industrial scale processes and supply and distribution networks. The third challenge demands rigorous focus on the applications where customers unambiguously recognize graphene’s unique value and for which graphene-enabled solutions eclipse all contenders.

Commercial graphene-enhanced products are penetrating niche markets with formulations demonstrating cost to performance ratios decisively better than the alternatives. And the production and supply issues impeding broader commercial development of graphene-based materials - including quantity, consistency, dependability, standardized characterization, certification, traceability and purity - are being remedied. Never-the-less, the number of deployments in high-volume graphene-enhanced application remains modest.

Let’s delve deeper into why this is so; and, then explore ways to accelerate graphene’s wider-adoption.

1) Building a Better Product Using Graphene – A View from the Material Engineering Lab
Nanomaterials – to the dismay of material engineers and production plant managers - store, transport, mix and behave markedly differently from their bulk material counterparts. Not only is the graphene nano-platelet characteristically distinct from the precursor graphite, but specific flake size, topology, and nuances of compound constitution and processing particulars influence nearly every aspect of how the material performs in the final application. At best, bulk material recipes serve only - but in not all cases - as rough starting points from which to begin iterative “expeditions” into uncharted design and engineering territory. Exploiting graphene’s exemplary properties requires iteratively investigating, testing and re-evaluating formulations, modifying existing processes, and adapting contemporary production equipment.

Figure 1 - A generalized development plan for graphene material applications

2) Harnessing Graphene as Enabler

Creating a graphene-enhanced compound typically begins with selection of a specific nanoplatelet profile of lateral size, thickness, defect density, purity and topology. Functionalization, in most instances, plays a pivotal role in dispersion and therefore the molecular bonds and structures assembled within the graphene-doped host matrix which impact the properties of the final and end product. Single digit % by weight graphene concentrations (and often less than 1% by weight) are common making process precision and consistency crucial. Commercially available matrix substances (typically polymers), various bulk ingredients and chemical additives are mixed per specified quantity and according to one, or a combination of, mechanical sheer milling, ultrasonic agitation or pressurization etc., techniques. Processing duration, extrusion method and temperature are just a few of the parameters adjusted during injection molding, thermal-set molding, spin drawing, aerosol spraying, dip coating, adsorption, relief printing etc. to yield the desired end component or product. All data including recipe, ingredient concentrations, process parameters are meticulously registered both quantitatively and qualitatively. The front end of the procedure appears in the graphic of Figure 2 below.

Figure 2 – Data collection in graphene formulation discovery

The network of Figure 3 below depicts material selection, ingredient integration, processing, preparation evaluation and the filtering of outcomes cascades through a maze of options. The exercise begins with selection of the graphene supply and proceeds though to completion of a selection of final compounds or a final product. Successive attempts are sorted according to ingredient constellation, concentration level, process parameter regime etc. The outcomes most closely approaching the desired product performance and estimated per unit production cost are used for subsequent trials.

Figure 3 – Recipe discovery - a labyrinth of options

Progressive iterations eventually coalesce into a small number of potentially most suitable “material recipes and process regimes”. Further refinements culminate in material assays, sub-component samples or final product prototypes demonstrating the characteristics, behavior, supply chain ecosystem fit and benchmark economic prerequisites before undertaking scale production of the winning viable intermediate component or the end product.

3) Solve Problems & Satisfy Needs with Graphene-Enhanced Materials
A formidable assortment of options and combinations of ingredients and procedures conspire to create a graphene-enhanced product destined for use as a vehicle component, battery electrode, integrated sensor module, anticorrosion chassis coating, rubber seal or auto dashboard – or even piece of sporting gear. Formulations, masterbatches and intermediate components may be marketed/sold separately to end up in any number of downstream products and applications. The Figure 4 below displays the major product development activities according to relevant development stages.

Figure 4 - The value creation chain for a graphene-enhanced product.

The arches traversing individual upstream and downstream value creation stages represent enquiries, specification requests, test protocols, parts, components, software code and exchange of standard business documentation. This bi-directional flow of human liaisons including problem solving sessions, teleconferences, schedule update meetings and business and industry forecast exchanges ricochet between partners and among collaborators. Each link of the chain represents an enterprise bound to reconcile its own technical, operational, and logistic capabilities and economic obligations. Close and dynamic collaboration is vital in charting routes through the network promising the best chance for success of individual contributors and the end user solution.

Figure 5 below illustrates the perspective of the graphene technologists peering downstream in search of problems in need of solving. They are eager to monetize exceptional effort, personal risk, patented intellectual property and acquired know how.

Figure 5 – View from the engineering lab

Improved functionality, reduced cost of ownership, appropriate certification, higher income garnering potential etc. must render value exceeding the price in light of alternative approaches including compensation for perceived risk, switching cost or similar disadvantages. However, if the inventive engineers lack information pertaining to the end customer’s problems, needs or wants, they may not be able to precisely identify the ultimate customer or enduser.

4) Problems, Needs and Unidentified Opportunities

Customers purchasing graphene enhanced products or materials expect to enjoy or otherwise benefit from the utility generated from these graphene-enhanced products. Owing to good luck, fortuitous contacts and helpful channels via suppliers, sales agents and distribution partners, a development team can gain at least some understanding of how graphene serves the application and lends value and satisfaction to end customers. Figure 6 portrays the customer’s viewpoint.

Figure 6 – View from the customer

The benefits of graphene are diverse and varied and determined by the appraisal of the product’s functional and economic attributes by the customer and buying influencers. Cost savings, space savings, flexibility of use, physical attractiveness, prestige, ease of maintenance, product safety, peace of mind and enhanced value and finally desirability in terms of the customer’s customers are a few examples of value. An enterprise selling / delivering the value is rewarded in terms of purchase price, future repurchases, volume orders, collaborative relationships, ecosystem intelligence etc.

In the case of graphene or other novel or disruptive technologically driven innovations, any departure from standard application methods, practices or fulfillment models requires increased attention to issues not encumbering traditional or entrenched competitors – initially. Particularly for graphene, prospects with potential to disburse large orders reciprocally demand delivery quantities and lead times unattainable for shops not yet operating at industrial sale. Conversely, suppliers of ingredients, plant and equipment tend to eschew new enterprises lacking financial gravitas. Instead, innovative companies must play to their strengths: flexibility, speed and readiness to work collaboratively in revealing, inventing, testing and fine-tuning formulations and products that address the customer’s needs, mitigating the user’s problems in ways competing offers cannot. Figure 7 below summarizes how the innovator views the endeavor and the customer considers purchasing the graphene-enhanced product.

Figure 7 – Successful Innovation and the Meeting of Minds

5) Problems, Needs and Unidentified Opportunities

How does one acquire a relevant and unambiguous overview of the utility, benefit and advantages graphene products should target? Market studies offer a perspective of industry fundamentals, market size and trends, existing benchmarks and statistics. Trade shows and industry events provide information regarding the ecosystem’s competitive landscape, technological progress and future developments. However, speaking directly with customers represented by Product Managers, CTOs, Marketing Managers and Distribution Partners confers more specific and highly relevant detail. And building relationships with customer groups as well as other stakeholders proves immeasurably helpful in uncovering latent needs, unappreciated deficiencies and previously unarticulated insights.

Interactions with customers as well as upstream and downstream value chain stakeholders including suppliers, service providers and manufacturing partners typically yields highly useful information concerning production methods, process short cuts, unexpected and unexpressed potential for cost savings or unrealized means for improving product quality, logistics or utility that are normally inaccessible to laboratory denizens. Even financiers may lend assistance through discussing strategy in terms of key industry metrics, opening doors to export prospects or building bridges to large buyer consortiums and industry clusters.

Most importantly, direct interfacing and repeated interaction with value chain stakeholders - from suppliers to endusers, installers and support services – offers valuable observations and breeds trust and collaboration. A much broader and deeper reserve of know-how, skills and information may be brought to bear in seizing the maximum portion of problem space with valuable, practicable and profitable solutions, as depicted in Figure 8.

Figure 8 – Successful Innovation - a Meeting of Minds, Technology and Resources

6) Lessons Learning

Three major issues have come to light during attempts to commercialize graphene-based solutions directed at real world problems and inadequacies. Successful market innovations combine and integrate the know-how and capabilities of graphene scientists together with value chain partners to solve the customer’s problem. Value is generated and equitably distributed sufficient to incentivize all stakeholders and customers to perpetuate collaboration, production and further innovation.

Figure 9 displays the three areas where proficiency becomes vital in successfully bringing graphene-enhanced products to markets and individual customers and clients.

Figure 9 The Sweet Spot Driving Collaborative Commercially Successful Innovation

a) Technical: Solving practical problems and grasping exciting opportunities demands technically feasible, stable and scalable solutions, whether materials, formulations, compounds, components or end products.

b) Business Case: The process of delivering solutions using graphene must be economically and commercially sound and sustainable for all value creation chain contributors from the graphene supplier to the final purchaser. This holds true across contributors; viable business case must hold for each stage.

c) Stakeholders: Developing, producing and then scaling novel materials and products requires the combined interest, commitment, investment and ideas only achievable via concerted collaborative engagement and mutual reward. A team approach is essential to overcome challenges at each stage progressing from raw material to actual application and final recycling.

Graphene nanoplatelets are a substance unlike the bulk material graphite from which it is made, or like other bulk materials used in traditional product design. At an advanced level, exploiting the functional possibilities of graphene, (electrical conductivity, tensile strength, chemical affinity and compatibility with multilaminar plastic extrusion techniques, etc.) is ONLY achieved through exemplary collaboration.

7) Conclusion

Three observations are noteworthy. They allude to different ways of managing teams, dealing with uncertainty and discovering what and how products earn their worth. The journey from the lab to installation in the latest model of automobiles is a longer and more tortious path for graphene products than it has been for traditional materials. The skills threshold has been raised for business development and product management professionals orchestrating commercialization. Re-training with new conceptual tools and software aids is on the agenda for the entire team stretching from development laboratory to the end user. A refurbished and invigorated organizational dynamic will be needed to meet the challenge.

a) Graphene is a multifaceted and complex material demanding engineering ingenuity to unleash its potential. Intermediaries further down the value creation chain applying conventional equipment to fashion contemporary materials must learn to experiment, adapt, improvise and collaborate;

b) Graphene pioneers must strive via all possible means and channels to understand the process prerequisites, performance expectations and appreciated worth of innovations in the eyes of the customer, enduser but also intermediate value chain partners. The ability to deliver value to customers depends as much on uncovering and serving latent opportunities as solving salient customer urgent problems lucrative opportunities.

c) No catalogue of graphene formulations combined with common and exotic matrix materials, additives, process methods and forming techniques presently exists. Working as an extended team between vendor and customer, service provider and users along the span of the manufacturing network is vital to navigating the path toward launching commercially successful next generation of functional materials.

Tags:  2D materials  Francis Nedvidek  Graphene  Graphite  Material Engineering Lab  Nanomaterials  University of Dresden 

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Graphene Surprises Researchers Again: Strange ‘Melting’ Behavior

Posted By Graphene Council, Monday, January 6, 2020
Physicists from the Moscow Institute of Physics and Technology and the Institute for High Pressure Physics of the Russian Academy of Sciences have used computer modeling to refine the melting curve of graphite that has been studied for over 100 years, with inconsistent findings. They also found that graphene “melting” is in fact sublimation. The results of the study came out in the journal Carbon.

Graphite is a material widely used in various industries — for example in heat shields for spacecraft — so accurate data on its behavior at ultrahigh temperatures is of paramount importance. Graphite melting has been studied since the early 20th century. About 100 experiments have placed the graphite melting point at various temperatures between 3,000 and 7,000 kelvins. With a spread so large, it is unclear which number is true and can be considered the actual melting point of graphite. The values returned by different computer models are also at variance with each other.

A team of physicists from MIPT and HPPI RAS compared several computer models to try and find the matching predictions. Yuri Fomin and Vadim Brazhkin used two methods: classical molecular dynamics and ab initio molecular dynamics. The latter accounts for quantum mechanical effects, making it more accurate. The downside is that it only deals with interactions between a small number of atoms on short time scales. The researchers compared the obtained results with prior experimental and theoretical data.

Fomin and Brazhkin found the existing models to be highly inaccurate. But it turned out that comparing the results produced by different theoretical models and finding overlaps can provide an explanation for the experimental data.

As far back as 1960s, the graphite melting curve was predicted to have a maximum. Its existence points to complex liquid behavior, meaning that the structure of the liquid rapidly changes on heating or densification. The discovery of the maximum was heavily disputed, with a number of studies confirming and challenging it over and over. Fomin and Brazhkin’s results show that the liquid carbon structure undergoes changes above the melting curve of graphene. The maximum therefore has to exist.

The second part of the study is dedicated to studying the melting of graphene. No graphene melting experiments have been conducted. Previously, computer models predicted the melting point of graphene at 4,500 or 4,900 K. Two-dimensional carbon was therefore considered to have the highest melting point in the world.

“In our study, we observed a strange ‘melting’ behavior of graphene, which formed linear chains. We showed that what happens is it transitions from a solid directly into a gaseous state. This process is called sublimation,” commented Associate Professor Yuri Fomin of the Department of General Physics, MIPT. The findings enable a better understanding of phase transitions in low-dimensional materials, which are considered an important component of many technologies currently in development, in fields from electronics to medicine.

The researchers produced a more precise and unified description of how the graphite melting curve behaves, confirming a gradual structural transition in liquid carbon. Their calculations show that the melting temperature of graphene in an argon atmosphere is close to the melting temperature of graphite.

Tags:  2D materials  Graphene  Graphite  Moscow Institute of Physics and Technology  Nanotechnology  Vadim Brazhkin  Yuri Fomin 

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High-performance anode for all-solid-state Li batteries is made of Si nanoparticles

Posted By Graphene Council, Tuesday, December 31, 2019
A new study led by NIMS researchers reveals that, in solid electrolytes, a Si anode composed only of commercial Si nanoparticles prepared by spray deposition -- the method is a cost-effective, atmospheric technique -- exhibits excellent electrode performance, which has previously been observed only for film electrodes prepared by evaporation processes. This new result therefore suggests that a low-cost and large-scale production of high-capacity anodes for use in all-solid-state Li batteries is possible.

Si has a theoretical capacity of ~4,200 mAh/g, which is approximately 11 times higher than that of the graphite commonly used as the anode-active material in commercial Li-ion batteries. Replacing the traditional graphite by Si can extend significantly the driving range per charge of electric vehicles. However, its huge volume change (~300%) during lithiation and delithiation -- charge and discharge -- hinders its practical application in the batteries. In conventional liquid electrolytes, the use of polymeric binders is necessary to hold the active material particles in the electrode together and maintain their adhesion to the surface of metal current collectors. The repeated huge volume change of Si causes the particle isolation and thus leads to losing the active material, which results in a continuous capacity loss. In solid-state cells, the active material is placed between two solid components -- solid electrolyte separator layer and metal current collector --, which enables avoidance of tackling the problem -- electrical isolation of the active material --. In fact, as reported previously by the team of NIMS researchers, the sputter-deposited pure Si films delivering practical areal capacities exceeding 2.2 mAh/cm2 exhibit excellent cycling stability and high-rate discharge capabilities in solid electrolytes. Nonetheless, cost-effective and industrially scalable synthesis of the anode for all-solid-state Li batteries remains a great challenge.

The team of NIMS researchers has taken another synthesis approach toward develop the high-performance anode for all-solid-state Li batteries with commercial Si nanoparticles, and found a unique phenomenon to the nanoparticles in the solid-state cell: upon lithiation, they undergo volume expansion, structural compaction, and appreciable coalescence in the confined space between the solid electrolyte separator layer and metal current collector to form a continuous film similar to that prepared by the evaporation process. The anode composed of nanoparticles prepared by spray deposition therefore exhibits excellent electrode performance, which has previously been observed only for sputter-deposited film electrodes. The spray deposition method is a cost-effective, atmospheric technique that can be used for large-scale production. Hence, the findings will pave the way for low-cost and large-scale production of high-capacity anodes for use in all-solid-state Li batteries.

Continuing efforts by the team of NIMS researchers to improve the cyclability in the anode having the increased areal mass loading of nanoparticles are in progress to meet the requirements of electric vehicles.

Tags:  Electric Vehicle  Graphene  Graphite  Li-ion batteries  nanoparticles  National Institute for Materials Science 

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GRATOMIC RECEIVES FIRST TWO PURCHASE ORDERS FOR PRE-GRAPHENE GRAPHITE FROM TODAQ

Posted By Graphene Council, Saturday, December 21, 2019
Gratomic Inc a vertically integrated graphite to graphenes, advanced materials development company announces it has received its first two purchase orders for a total of USD 6 Million following a previously announced supply agreement on October 17, 2019 (https://gratomic.ca/gratomic-signs-deal-to-supply-graphite-to-todaq/) for an aggregate of USD $25,000,000 of graphite in an all-digital-asset deal from TODAQ STAR Program Phase 1 Corp, a subsidiary of TODAQ Holdings. The purchase orders are each for 600 tonnes of graphite valued at USD $6,000,000 solely payable in TDN at a price of USD$0.10 per TDN for an aggregate of TDN 60,000,000 that is to be delivered within 90 days.

Subsequent to the success of the initial delivery, TODAQ will place one additional order of 600 tonnes of graphite with 30 day intervals bringing the total to 1800 tonnes of graphite for USD $9,000,000 in consideration for the issuance of an aggregate of 90 million TDN. Thereafter, TODAQ will place orders on a monthly basis with the value of USD $484,848.49 based on both the purchase price for graphite and the exchange between USD and TDN applicable at the time over a period of 39 months.

The agreement marks the first steps towards a significant journey for Sovereignty Tech pioneer TODAQ, with a strategic intention towards both building its TDN rewards program and allowing cryptographic ownership of commodities so that all business, people and markets can transact quickly with security and long-term stability. Furthermore, the graphite will sit in the TDN reserve backstop as part of a diverse set of commodities to underpin the true value of deployed TDN with physical substance and utility.

No mineral resources, let alone mineral reserves demonstrating economic viability and technical feasibility, have been delineated on the Aukam Property. The Company is not in a position to demonstrate or disclose any capital and/or operating costs that may be associated with satisfying the terms of the Todaq Supply Agreement.

Gratomic wishes to emphasize that Supply Agreement is conditional on Gratomic being able to bring the Aukam project into a production phase, and for any graphite being produced to meet certain technical and mineralization requirements.

Gratomic continues to move its business towards production and as part of its business plan, expects to obtain a National Instrument 43-101 Standards of Disclosure for Mineral Projects technical report to help it ascertain the economics of Aukam. Presently the Company uses its existing pilot processing facility to produce certain amounts of graphite concentrate from accumulated surface graphite.

Risk Factors

The Company advises that it has not based its production decision on even the existence of mineral resources let alone on a feasibility study of mineral reserves, demonstrating economic and technical viability, and, as a result, there may be an increased uncertainty of achieving any particular level of recovery of minerals or the cost of such recovery, including increased risks associated with developing a commercially mineable deposit.

The Supply Agreement provides that if Gratomic is unable to deliver graphite in accordance with the orders from Todaq, Todaq has the right to refuse to take any subsequent attempt to fulfil the order, terminate the agreement immediately, obtain substitute product from another supplier and recover from the Company any costs and expenses incurred in obtaining such substitute product or suing for damages under the contract.

Historically, such projects have a much higher risk of economic and technical failure. There is no guarantee that production will begin as anticipated or at all or that anticipated production costs will be achieved.

Failure to commence production would have a material adverse impact on the Company's ability to generate revenue and cash flow to fund operations. Failure to achieve the anticipated production costs would have a material adverse impact on the Company's cash flow and future profitability.

Steve Gray, P.Geo. has reviewed, prepared and approved the scientific and technical information in this press release and is Gratomic Inc's "Qualified Person" as defined by National Instrument 43-101 - Standards of Disclosure for Mineral Projects.

Tags:  Graphene  Graphite  Gratomic  P.Geo  Steve Gray  TODAQ 

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Successful Share Purchase Plan Closes

Posted By Graphene Council, Wednesday, December 11, 2019
Advanced battery anode materials and graphene additives provider Talga Resources is pleased to advise its Share Purchase Plan (“SPP”) closed on Friday, 6 December 2019 after attracting strong participation, with demand for the SPP well in excess of the funds initially sought to be raised.

Talga has received applications under the SPP in excess of A$6.0 million. The Company had previously announced it was targeting A$3.0 million under the SPP, with the Talga Board having discretion to accept oversubscriptions above this limit.

In response to the strong shareholder support the Talga Board has decided that all eligible shareholders who applied for shares under the SPP will receive their full allocation of shares in accordance with the SPP terms and conditions.

The additional capital, beyond the initial target of A$3.0 million, will be used to enhance Talga’s financial flexibility as the Company progresses its short- and medium-term plans, including scaleup of Talnode®-C production for customer qualifications.

Talga Non-executive Chairman, Mr Terry Stinson: “Our aim with the Share Purchase Plan was to provide existing shareholders the opportunity to increase their holdings on the same terms as the recently completed institutional placement - with proceeds used towards funding the last stage of development prior to planned project funding for the Vittangi Graphite Anode Project.

The success of the SPP clearly demonstrates the continued strong support from our shareholders as we progress the execution of our vertically integrated battery anode and graphene additives business strategies. On behalf of the Company, I would like to thank shareholders for their continued support.”

In accordance with the SPP terms, the issue price of the new shares will be A$0.44 per share, being the same price as the issue of shares under the recently completed institutional placement (ASX:TLG 15 Nov 2019 and 21 Nov 2019).

The Company is working with its share registry Security Transfer Australia Pty Ltd to finalise the review of the SPP applications. New fully paid ordinary shares are expected to be issued to eligible applicants under the SPP on Friday, 13 December 2019, once processing of applications has been finalised.

Tags:  Graphene  Graphite  Talga Resources  Terry Stinson 

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Solving the mystery of carbon on ocean floor

Posted By Graphene Council, Friday, December 6, 2019
For years, researchers looking at seafloor sediments would find bits of black carbon along with organic carbon strewn across the ocean floor, but they couldn't say exactly where it originated. The challenge with studying deep marine carbon is that it is a mixture of fresh material delivered from the surface and an aged component, the origin of which had been previously unknown.

Now, a new University of Delaware study recently published in Nature Communications shows for the first time that the old carbon found on the seafloor can be directly linked to submicron graphite particles emanating from hydrothermal vents.

Identifying the sources, transport pathways and the fate of this seafloor carbon is key to understanding the dynamics of the marine carbon cycle.

The ocean acts as a reservoir for substantial amounts of both organic carbon and carbon dioxide, which can lead to ocean acidification or be converted to form organic carbon via photosynthesis. Thus, it is important to understand how carbon moves between different phases in the ocean and how it might become sequestered in the deep ocean for extremely long periods of time. This work shows that organic carbon and carbon dioxide can also be converted at vents to another form of carbon, graphite.

The study was led by Emily Estes, a former post-doctoral researcher at UD who is now a staff scientist with the International Ocean Discovery Program at Texas A&M University, and George Luther, the Maxwell P. and Mildred H. Harrington Professor of Marine Chemistry and the Francis Alison Professor in UD's College of Earth, Ocean and Environment (CEOE).

To conduct their study, the researchers used samples of nanoparticles from five different hydrothermal vent sites collected during a research expedition to the East Pacific Rise vent field in the Pacific Ocean in 2017, funded by the National Science Foundation's marine geology and geophysics program.

Estes conducted shipboard sampling of hydrothermal vent fluids and particulates during the expedition, which was led by Luther.

When they got back from the research cruise and wanted to take a deeper look at what they collected, the samples were analyzed under scanning and transmission microscopes by colleagues at the National Center for Earth and Environmental Nanotechnology Infrastructure (NanoEarth) at Virginia Tech.

Once they looked at the results, Estes noticed a large number of submicron graphite particles, similar to what would be found in an everyday lead pencil, in the samples.

While it's known that graphite can form hydrothermally in sediments, this study showed that these sub-micron particles of graphite that come out of the vents occur consistently across a range of vent environments, including both focused high temperature and low temperature venting sites.

"Even though our study is a preliminary observation of these particles, it suggests that they're probably very widespread and could be a significant source of this type of carbon to the deep ocean," said Estes.

Overlooked graphite
Previous studies may have overlooked the significance of graphite particles because of the way in which dissolved organic carbon and particulate organic carbon are measured.

Working with Andrew Wozniak, assistant professor in the School of Marine Science and Policy in CEOE, and Nicole Coffey, a master's level student in CEOE who was also on the research cruise as an undergraduate in 2017, Estes and Luther were able to show that common techniques used to measure dissolved organic carbon or particulate organic carbon also pick up graphite.

Because graphite is only made up of carbon, however, if somebody just did a generic carbon-14 measurement, they might overlook that there's hydrothermal graphite in their sample.

"Graphite is not carbon with hydrogen, oxygen, nitrogen and other elements," said Luther. "So here's an inorganic form of carbon, because it's pure carbon, that's also being measured as organic carbon, whether it's dissolved or particulate."

Finding these submicron graphite particles helps to answer a mystery that has confounded researchers with regards to dissolved organic carbon in really deep ocean environments.

"If you measure the carbon-14 age on it, it comes out to be a little bit older than you would actually expect and so there's been a mystery surrounding what the source of this old organic carbon is," said Estes. "We showed that vents emit this graphitic carbon."

Another important point of the paper is that because these graphite submicron particles are not dense and emit from the hydrothermal vents in flat sheet-like structures, they have the potential to get entrained into ocean currents and distributed far away from the vent sites. This will be important to take into consideration for future research in regards to the marine carbon cycle.

"The next steps will be trying to actually quantify how much carbon is coming out of the vents and then compare that to what we measure as dissolved organic carbon in the ocean and figure out what part of the flux it is," said Estes.

Tags:  Emily Estes  Francis Alison  George Luther  Graphene  Graphite  University of Delaware  Virginia Tech 

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Graphene in Electronic Circuits

Posted By Graphene Council, Wednesday, July 31, 2019
Updated: Tuesday, July 30, 2019
Ever since graphene was discovered in 2004, researchers around the world have been working to develop commercially scalable applications for this high-performance material.

Graphene is 100 to 300 times stronger than steel at the atomic level and has a maximum electrical current density orders of magnitude greater than that of copper, making it the strongest, thinnest and, by far, the most reliable electrically conductive material on the planet. It is, therefore, an extremely promising material for interconnects, the fundamental components that connect billions of transistors on microchips in computers and other electronic devices in the modern world.

For over two decades, interconnects have been made of copper, but that metal encounters fundamental physical limitations as electrical components that incorporate it shrink to the nanoscale. “As you reduce the dimensions of copper wires, their resistivity shoots up,” said Kaustav Banerjee, a professor in the Department of Electrical and Computer Engineering. “Resistivity is a material property that is not supposed to change, but at the nanoscale, all properties change.”

As the resistivity increases, copper wires generate more heat, reducing their current-carrying capacity. It’s a problem that poses a fundamental threat to the $500 billion semiconductor industry. Graphene has the potential to solve that and other issues. One major obstacle, though, is designing graphene micro-components that can be manufactured on-chip, on a large scale, in a commercial foundry.

“Whatever the component, be it inductors, interconnects, antennas or anything else you want to do with graphene, industry will move forward with it only if you find a way to synthesize graphene directly onto silicon wafers,” Banerjee said. He explained that all manufacturing processes related to the transistors, which are made first, are referred to as the ‘front end.’ To synthesize something at the back-end — that is, after the transistors are fabricated — you face a tight thermal budget that cannot exceed a temperature of about 500 degrees Celsius. If the silicon wafer gets too hot during the back-end processes employed to fabricate the interconnects, other elements that are already on the chip may get damaged, or some impurities may start diffusing, changing the characteristics of the transistors.

Now, after a decade-long quest to achieve graphene interconnects, Banerjee’s lab has developed a method to implement high-conductivity, nanometer-scale doped multilayer graphene (DMG) interconnects that are compatible with high-volume manufacturing of integrated circuits. A paper describing the novel process was named one of the top papers at the 2018 IEEE International Electron Devices Meeting (IEDM),  from more than 230 that were accepted for oral presentations. It also was one of only two papers included in the first annual “IEDM Highlights” section of an issue of the journal Nature Electronics.

Banerjee first proposed the idea of using doped multi-layer graphene at the 2008 IEDM conference and has been working on it ever since. In February 2017 he led the experimental realization of the idea by Chemical Vapor Deposition (CVD) of multilayer graphene at a high temperature, subsequently transferring it to a silicon chip, then patterning the multilayer graphene, followed by doping. Electrical characterization of the conductivity of DMG interconnects down to a width of 20 nanometers established the efficacy of the idea that was proposed in 2008. However, the process was not “CMOS-compatible” (the standard industrial-scale process for making integrated circuits), since the temperature of CVD processes far exceed the thermal budget of back-end processes.

To overcome this bottleneck, Banerjee’s team developed a unique pressure-assisted solid-phase diffusion method for directly synthesizing a large area of high-quality multilayer graphene on a typical dielectric substrate used in the back-end CMOS process. Solid-phase diffusion, well known in the field of metallurgy and often used to form alloys, involves applying pressure and temperature to two different materials that are in close contact so that they diffuse into each other.

Banerjee’s group employed the technique in a novel way. They began by depositing solid-phase carbon in the form of graphite powder onto a deposited layer of nickel metal of optimized thickness. Then they applied heat (300 degrees Celsius) and nominal pressure to the graphite powder to help break down the graphite. The high diffusivity of carbon in nickel allows it to pass rapidly through the metal film.

How much carbon flows through the nickel depends on its thickness and the number of grains it holds. “Grains” refer to the fact that deposited nickel is not a single-crystal metal, but rather a polycrystalline metal, meaning it has areas where two single-crystalline regions meet each other without being perfectly aligned. These areas are called grain boundaries, and external particles — in this case, the carbon atoms — easily diffuse through them. The carbon atoms then recombine on the other surface of the nickel closer to the dielectric substrate, forming multiple graphene layers.

Banerjee’s group is able to control the process conditions to produce graphene of optimal thickness. “For interconnect applications, we know how many layers of graphene are needed,” said Junkai Jiang, a Ph.D. candidate in Banerjee’s lab and lead author of the 2018 IEDM paper. “So we optimized the nickel thickness and other process parameters to obtain precisely the number of graphene layers we want at the dielectric surface. “Subsequently, we simply remove the nickel by etching so that what’s left is only very high-quality graphene — virtually the same quality as graphene grown by CVD at very high temperatures,” he continued. “Because our process involves relatively low temperatures that pose no threat to the other fabricated elements on the chip, including the transistors, we can make the interconnects right on top of them.”

UCSB has filed a provisional patent on the process, which overcomes the obstacles that, until now, have prevented graphene from replacing copper. Bottom line: graphene interconnects help to create faster, smaller, lighter, more flexible, more reliable and more cost-effective integrated circuits. Banerjee is currently in talks with industry partners interested in potentially licensing this CMOS-compatible graphene synthesis technology, which could pave the way for what would be the first 2D material to enter the mainstream semiconductor industry.

Tags:  2D materials  CVD  Graphene  Graphite  Junkai Jiang  Kaustav Banerjee  Semiconductor  UC Santa Barbara 

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