Category Archives: graphene

R.I.P. Mildred Dresselhaus, Queen of Carbon

I’ve been hearing about Mildred Dresselhaus, professor emerita (retired professor) at the Massachusetts Institute of Technology (MIT), just about as long as I’ve been researching and writing about nanotechnology (about 10 years including the work for my master’s project with the almost eight years on this blog).

She died on Monday, Feb. 20, 2017 at the age of 86 having broken through barriers for those of her gender, barriers for her subject area, and barriers for her age.

Mark Anderson in his Feb. 22, 2017 obituary for the IEEE (Institute of Electrical and Electronics Engineers) Spectrum website provides a brief overview of her extraordinary life and accomplishments,

Called the “Queen of Carbon Science,” Dresselhaus pioneered the study of carbon nanostructures at a time when studying physical and material properties of commonplace atoms like carbon was out of favor. Her visionary perspectives on the sixth atom in the periodic table—including exploring individual layers of carbon atoms (precursors to graphene), developing carbon fibers stronger than steel, and revealing new carbon structures that were ultimately developed into buckyballs and nanotubes—invigorated the field.

“Millie Dresselhaus began life as the child of poor Polish immigrants in the Bronx; by the end, she was Institute Professor Emerita, the highest distinction awarded by the MIT faculty. A physicist, materials scientist, and electrical engineer, she was known as the ‘Queen of Carbon’ because her work paved the way for much of today’s carbon-based nanotechnology,” MIT president Rafael Reif said in a prepared statement.

Friends and colleagues describe Dresselhaus as a gifted instructor as well as a tireless and inspired researcher. And her boundless generosity toward colleagues, students, and girls and women pursuing careers in science is legendary.

In 1963, Dresselhaus began her own career studying carbon by publishing a paper on graphite in the IBM Journal for Research and Development, a foundational work in the history of nanotechnology. To this day, her studies of the electronic structure of this material serve as a reference point for explorations of the electronic structure of fullerenes and carbon nanotubes. Coauthor, with her husband Gene Dresselhaus, of a leading book on carbon fibers, she began studying the laser vaporation of carbon and the “carbon clusters” that resulted. Researchers who followed her lead discovered a 60-carbon structure that was soon identified as the icosahedral “soccer ball” molecular configuration known as buckminsterfullerene, or buckyball. In 1991, Dresselhaus further suggested that fullerene could be elongated as a tube, and she outlined these imagined objects’ symmetries. Not long after, researchers announced the discovery of carbon nanotubes.

When she began her nearly half-century career at MIT, as a visiting professor, women consisted of just 4 percent of the undergraduate student population.  So Dresselhaus began working toward the improvement of living conditions for women students at the university. Through her leadership, MIT adopted an equal and joint admission process for women and men. (Previously, MIT had propounded the self-fulfilling prophecy of harboring more stringent requirements for women based on less dormitory space and perceived poorer performance.) And so promoting women in STEM—before it was ever called STEM—became one of her passions. Serving as president of the American Physical Society, she spearheaded and launched initiatives like the Committee on the Status of Women in Physics and the society’s more informal committees of visiting women physicists on campuses around the United States, which have increased the female faculty and student populations on the campuses they visit.

If you have the time, please read Anderson’s piece in its entirety.

One fact that has impressed me greatly is that Dresselhaus kept working into her eighties. I featured a paper she published in an April 27, 2012 posting at the age of 82 and she was described in the MIT write up at the time as a professor, not a professor emerita. I later featured Dresselhaus in a May 31, 2012 posting when she was awarded the Kavli Prize for Nanoscience.

It seems she worked almost to the end. Recently, GE (General Electric) posted a video “What If Scientists Were Celebrities?” starring Mildred Dresselhaus,

H/t Mark Anderson’s obituary Feb. 22, 2017 piece. The video was posted on Feb. 8, 2017.

Goodbye to the Queen of Carbon!

Detonating (exploding) your way to graphene

Physicists at Kansas State University use controlled detonation to make graphene according to a Jan. 25, 2017 news item on Nanowerk (Note: A link has been removed),

Forget chemicals, catalysts and expensive machinery — a Kansas State University team of physicists has discovered a way to mass-produce graphene with three ingredients: hydrocarbon gas, oxygen and a spark plug.

Their method is simple: Fill a chamber with acetylene or ethylene gas and oxygen. Use a vehicle spark plug to create a contained detonation. Collect the graphene that forms afterward.

Chris Sorensen, Cortelyou-Rust university distinguished professor of physics, is the lead inventor of the recently issued patent, “Process for high-yield production of graphene via detonation of carbon-containing material”. Other Kansas State University researchers involved include Arjun Nepal, postdoctoral researcher and instructor of physics, and Gajendra Prasad Singh, former visiting scientist.

For further reading here’s the Jan. 25, 2017 Kansas State University news release, which originated the news item,

“We have discovered a viable process to make graphene,” Sorensen said. “Our process has many positive properties, from the economic feasibility, the possibility for large-scale production and the lack of nasty chemicals. What might be the best property of all is that the energy required to make a gram of graphene through our process is much less than other processes because all it takes is a single spark.”

Graphene is a single atom-thick sheet of hexagonally coordinated carbon atoms, which makes it the world’s thinnest material. Since graphene was isolated in 2004, scientists have found it has valuable physical and electronic properties with many possible applications, such as more efficient rechargeable batteries or better electronics.

For Sorensen’s research team, the serendipitous path to creating graphene started when they were developing and patenting carbon soot aerosol gels. They created the gels by filling a 17-liter aluminum chamber with acetylene gas and oxygen. Using a spark plug, they created a detonation in the chamber. The soot from the detonation formed aerosol gels that looked like “black angel food cake,” Sorensen said.

But after further analysis, the researchers found that the aerosol gel was more than lookalike dark angel food cake — it was graphene.

“We made graphene by serendipity,” Sorensen said. “We didn’t plan on making graphene. We planned on making the aerosol gel and we got lucky.”

But unlike other methods of creating graphene, Sorensen’s method is simple, efficient, low-cost and scalable for industry.

Other methods of creating graphene involve “cooking” the mineral graphite with chemicals — such as sulfuric acid, sodium nitrate, potassium permanganate or hydrazine — for a long time at precisely prescribed temperatures. Additional methods involve heating hydrocarbons to 1,000 degrees Celsius in the presence of catalysts.

Such methods are energy intensive — and even dangerous — and have low yield, while Sorensen and his team’s method makes larger quantities with minimal energy and no dangerous chemicals.

“The real charm of our experiment is that we can produce graphene in the quantity of grams rather than milligrams,” Nepal said.

Now the research team — including Justin Wright, doctoral student in physics, Camp Hill, Pennsylvania — is working to improve the quality of the graphene and scale the laboratory process to an industrial level. They are upgrading some of the equipment to make it easier to get graphene from the chamber seconds — rather than minutes — after the detonation. Accessing the graphene more quickly could improve the quality of the material, Sorensen said.

The patent was issued to the Kansas State University Research Foundation, a nonprofit corporation responsible for managing technology transfer activities at the university.

I wish they’d filmed one of their graphene explosions even if it meant that all we’d get is the sight of a canister and the sound of a boom. Still, they did show a brief spark from the spark plug.

Little black graphene dress

Graphene Dress. Courtesy: intu

I don’t think there are many women who can carry off this garment. Of course that’s not the point as the dress is designed to show off its technical capabilities. A Jan. 31, 2017 news item on Nanowerk announces the little black graphene dress (lbgd?),

Science and fashion have been brought together to create the world’s most technically advanced dress, the intu Little Black Graphene Dress.

The new prototype garment showcases the future uses of the revolutionary, Nobel Prize winning material graphene and incorporating it into fashion for the first time, in the ultimate wearable tech statement garment.

A Jan. 25, 2017 National Graphene Institute at University of Manchester press release, which originated the news item, expands on the theme,

The project between intu Trafford Centre, renowned wearable tech company Cute Circuit which has made dresses for the likes of Katy Perry and Nicole Scherzinger and the National Graphene Institute at The University of Manchester, uses graphene in a number of innovative ways to create the world’s most high tech LBD – highlighting the material’s incredible properties.

The dress is complete with a graphene sensor which captures the rate in which the wearer is breathing via a contracting graphene band around the models waist, the micro LED which is featured across the bust on translucent conductive graphene responds to the sensor making the LED flash and changing colour depending on breathing rate. It marks a major step in the future uses of graphene in fashion where it is hoped the highly conductive transparent material could be used to create designs which act as screens showcasing digital imagery which could be programmed to change and updated by the wearer meaning one garment could be in any colour hue or design.

The 3D printed graphene filament shows the intricate structural detail of graphene in raised diamond shaped patterns and showcases graphene’s unrivalled conductivity with flashing LED lights.

The high tech LBD can be controlled by The Q app created by Cute Circuit to change the way the garment illuminates.

The dress was created by the Manchester shopping centre to celebrate Manchester’s crown as the European City of Science. The dress will then be on display at intu Trafford Centre, it will then be available for museums and galleries to loan for fashion displays.

Richard Paxton, general manager at intu Trafford Centre said: “We have a real passion for fashion and fashion firsts, this dress is a celebration of Manchester, its amazing love for innovation and textiles, showcasing this new wonder material in a truly unique and exciting way. It really is the world’s most high-tech dress featuring the most advanced super-material and something intu is very proud to have created in collaboration with Cute Circuit and the National Graphene Institute. Hopefully this project inspires more people to experiment with graphene and its wide range of uses.”

Francesca Rosella, Chief Creative Director for Cute Circuit said: “This was such an exciting project for us to get involved in, graphene has never been used in the fashion industry and being the first to use it was a real honour allowing us to have a lot of fun creating the stunning intu Little Black Graphene Dress, and showcasing graphene’s amazing properties.”

Dr Paul Wiper, Research Associate, National Graphene Institute said: “This is a fantastic project, graphene is still very much at its infancy for real-world applications and showcasing its amazing properties through the forum of fashion is very exciting. The dress is truly a one of a kind and shows what creativity, imagination and a desire to innovate can create using graphene and related two-dimensional materials.”

The dress is modelled by Britain’s Next Top Model finalist Bethan Sowerby who is from Manchester and used to work at intu Trafford Centre’s Top Shop.

Probably not coming soon to a store near you.

Developing cortical implants for future speech neural prostheses

I’m guessing that graphene will feature in these proposed cortical implants since the project leader is a member of the Graphene Flagship’s Biomedical Technologies Work Package. (For those who don’t know, the Graphene Flagship is one of two major funding initiatives each receiving funding of 1B Euros over 10 years from the European Commission as part of their FET [Future and Emerging Technologies)] Initiative.)  A Jan. 12, 2017 news item on Nanowerk announces the new project (Note: A link has been removed),

BrainCom is a FET Proactive project, funded by the European Commission with 8.35M€ [8.3 million Euros] for the next 5 years, holding its Kick-off meeting on January 12-13 at ICN2 (Catalan Institute of Nanoscience and Nanotechnology) and the UAB [ Universitat Autònoma de Barcelona]. This project, coordinated by ICREA [Catalan Institution for Research and Advanced Studies] Research Prof. Jose A. Garrido from ICN2, will permit significant advances in understanding of cortical speech networks and the development of speech rehabilitation solutions using innovative brain-computer interfaces.

A Jan. 12, 2017 ICN2 press release, which originated the news item expands on the theme (it is a bit repetitive),

More than 5 million people worldwide suffer annually from aphasia, an extremely invalidating condition in which patients lose the ability to comprehend and formulate language after brain damage or in the course of neurodegenerative disorders. Brain-computer interfaces (BCIs), enabled by forefront technologies and materials, are a promising approach to treat patients with aphasia. The principle of BCIs is to collect neural activity at its source and decode it by means of electrodes implanted directly in the brain. However, neurorehabilitation of higher cognitive functions such as language raises serious issues. The current challenge is to design neural implants that cover sufficiently large areas of the brain to allow for reliable decoding of detailed neuronal activity distributed in various brain regions that are key for language processing.

BrainCom is a FET Proactive project funded by the European Commission with 8.35M€ for the next 5 years. This interdisciplinary initiative involves 10 partners including technologists, engineers, biologists, clinicians, and ethics experts. They aim to develop a new generation of neuroprosthetic cortical devices enabling large-scale recordings and stimulation of cortical activity to study high level cognitive functions. Ultimately, the BraimCom project will seed a novel line of knowledge and technologies aimed at developing the future generation of speech neural prostheses. It will cover different levels of the value chain: from technology and engineering to basic and language neuroscience, and from preclinical research in animals to clinical studies in humans.

This recently funded project is coordinated by ICREA Prof. Jose A. Garrido, Group Leader of the Advanced Electronic Materials and Devices Group at the Institut Català de Nanociència i Nanotecnologia (Catalan Institute of Nanoscience and Nanotechnology – ICN2) and deputy leader of the Biomedical Technologies Work Package presented last year in Barcelona by the Graphene Flagship. The BrainCom Kick-Off meeting is held on January 12-13 at ICN2 and the Universitat Autònoma de Barcelona (UAB).

Recent developments show that it is possible to record cortical signals from a small region of the motor cortex and decode them to allow tetraplegic [also known as, quadriplegic] people to activate a robotic arm to perform everyday life actions. Brain-computer interfaces have also been successfully used to help tetraplegic patients unable to speak to communicate their thoughts by selecting letters on a computer screen using non-invasive electroencephalographic (EEG) recordings. The performance of such technologies can be dramatically increased using more detailed cortical neural information.

BrainCom project proposes a radically new electrocorticography technology taking advantage of unique mechanical and electrical properties of novel nanomaterials such as graphene, 2D materials and organic semiconductors.  The consortium members will fabricate ultra-flexible cortical and intracortical implants, which will be placed right on the surface of the brain, enabling high density recording and stimulation sites over a large area. This approach will allow the parallel stimulation and decoding of cortical activity with unprecedented spatial and temporal resolution.

These technologies will help to advance the basic understanding of cortical speech networks and to develop rehabilitation solutions to restore speech using innovative brain-computer paradigms. The technology innovations developed in the project will also find applications in the study of other high cognitive functions of the brain such as learning and memory, as well as other clinical applications such as epilepsy monitoring.

The BrainCom project Consortium members are:

  • Catalan Institute of Nanoscience and Nanotechnology (ICN2) – Spain (Coordinator)
  • Institute of Microelectronics of Barcelona (CNM-IMB-CSIC) – Spain
  • University Grenoble Alpes – France
  • ARMINES/ Ecole des Mines de St. Etienne – France
  • Centre Hospitalier Universitaire de Grenoble – France
  • Multichannel Systems – Germany
  • University of Geneva – Switzerland
  • University of Oxford – United Kingdom
  • Ludwig-Maximilians-Universität München – Germany
  • Wavestone – Luxembourg

There doesn’t seem to be a website for the project but there is a BrainCom webpage on the European Commission’s CORDIS (Community Research and Development Information Service) website.

Fusing graphene flakes for 3D graphene structures that are 10x as strong as steel

A Jan. 6, 2017 news item on Nanowerk describes how geometry may have as much or more to do with the strength of 3D graphene structures than the graphene used to create them,

A team of researchers at MIT [Massachusetts Institute of Technology] has designed one of the strongest lightweight materials known, by compressing and fusing flakes of graphene, a two-dimensional form of carbon. The new material, a sponge-like configuration with a density of just 5 percent, can have a strength 10 times that of steel.

In its two-dimensional form, graphene is thought to be the strongest of all known materials. But researchers until now have had a hard time translating that two-dimensional strength into useful three-dimensional materials.

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

The findings are being reported today [Jan. 6, 2017\ in the journal Science Advances, in a paper by Markus Buehler, the head of MIT’s Department of Civil and Environmental Engineering (CEE) and the McAfee Professor of Engineering; Zhao Qin, a CEE research scientist; Gang Seob Jung, a graduate student; and Min Jeong Kang MEng ’16, a recent graduate.

A Jan. 6, 2017 MIT news release (also on EurekAlert), which originated the news item, describes the research in more detail,

Other groups had suggested the possibility of such lightweight structures, but lab experiments so far had failed to match predictions, with some results exhibiting several orders of magnitude less strength than expected. The MIT team decided to solve the mystery by analyzing the material’s behavior down to the level of individual atoms within the structure. They were able to produce a mathematical framework that very closely matches experimental observations.

Two-dimensional materials — basically flat sheets that are just one atom in thickness but can be indefinitely large in the other dimensions — have exceptional strength as well as unique electrical properties. But because of their extraordinary thinness, “they are not very useful for making 3-D materials that could be used in vehicles, buildings, or devices,” Buehler says. “What we’ve done is to realize the wish of translating these 2-D materials into three-dimensional structures.”

The team was able to compress small flakes of graphene using a combination of heat and pressure. This process produced a strong, stable structure whose form resembles that of some corals and microscopic creatures called diatoms. These shapes, which have an enormous surface area in proportion to their volume, proved to be remarkably strong. “Once we created these 3-D structures, we wanted to see what’s the limit — what’s the strongest possible material we can produce,” says Qin. To do that, they created a variety of 3-D models and then subjected them to various tests. In computational simulations, which mimic the loading conditions in the tensile and compression tests performed in a tensile loading machine, “one of our samples has 5 percent the density of steel, but 10 times the strength,” Qin says.

Buehler says that what happens to their 3-D graphene material, which is composed of curved surfaces under deformation, resembles what would happen with sheets of paper. Paper has little strength along its length and width, and can be easily crumpled up. But when made into certain shapes, for example rolled into a tube, suddenly the strength along the length of the tube is much greater and can support substantial weight. Similarly, the geometric arrangement of the graphene flakes after treatment naturally forms a very strong configuration.

The new configurations have been made in the lab using a high-resolution, multimaterial 3-D printer. They were mechanically tested for their tensile and compressive properties, and their mechanical response under loading was simulated using the team’s theoretical models. The results from the experiments and simulations matched accurately.

The new, more accurate results, based on atomistic computational modeling by the MIT team, ruled out a possibility proposed previously by other teams: that it might be possible to make 3-D graphene structures so lightweight that they would actually be lighter than air, and could be used as a durable replacement for helium in balloons. The current work shows, however, that at such low densities, the material would not have sufficient strength and would collapse from the surrounding air pressure.

But many other possible applications of the material could eventually be feasible, the researchers say, for uses that require a combination of extreme strength and light weight. “You could either use the real graphene material or use the geometry we discovered with other materials, like polymers or metals,” Buehler says, to gain similar advantages of strength combined with advantages in cost, processing methods, or other material properties (such as transparency or electrical conductivity).

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

The unusual geometric shapes that graphene naturally forms under heat and pressure look something like a Nerf ball — round, but full of holes. These shapes, known as gyroids, are so complex that “actually making them using conventional manufacturing methods is probably impossible,” Buehler says. The team used 3-D-printed models of the structure, enlarged to thousands of times their natural size, for testing purposes.

For actual synthesis, the researchers say, one possibility is to use the polymer or metal particles as templates, coat them with graphene by chemical vapor deposit before heat and pressure treatments, and then chemically or physically remove the polymer or metal phases to leave 3-D graphene in the gyroid form. For this, the computational model given in the current study provides a guideline to evaluate the mechanical quality of the synthesis output.

The same geometry could even be applied to large-scale structural materials, they suggest. For example, concrete for a structure such a bridge might be made with this porous geometry, providing comparable strength with a fraction of the weight. This approach would have the additional benefit of providing good insulation because of the large amount of enclosed airspace within it.

Because the shape is riddled with very tiny pore spaces, the material might also find application in some filtration systems, for either water or chemical processing. The mathematical descriptions derived by this group could facilitate the development of a variety of applications, the researchers say.

“This is an inspiring study on the mechanics of 3-D graphene assembly,” says Huajian Gao, a professor of engineering at Brown University, who was not involved in this work. “The combination of computational modeling with 3-D-printing-based experiments used in this paper is a powerful new approach in engineering research. It is impressive to see the scaling laws initially derived from nanoscale simulations resurface in macroscale experiments under the help of 3-D printing,” he says.

This work, Gao says, “shows a promising direction of bringing the strength of 2-D materials and the power of material architecture design together.”

There’s a video describing the work,

Here’s a link to and a citation for the paper,

The mechanics and design of a lightweight three-dimensional graphene assembly by Zhao Qin, Gang Seob Jung, Min Jeong Kang, and Markus J. Buehler. Science Advances  06 Jan 2017: Vol. 3, no. 1, e1601536 DOI: 10.1126/sciadv.1601536  04 January 2017

This paper appears to be open access.

Nano-chimneys to cut down heat

Heat is always a problem with electronics—even nanoelectronics. Scientists at Rice University (US) believe they may have a solution for nanoelectronics heat problems, according to a Jan. 4, 2017 news item on ScienceDaily,

A few nanoscale adjustments may be all that is required to make graphene-nanotube junctions excel at transferring heat, according to Rice University scientists.

The Rice lab of theoretical physicist Boris Yakobson found that putting a cone-like “chimney” between the graphene and [carbon] nanotube all but eliminates a barrier that blocks heat from escaping.

Caption: Simulations by Rice University scientists show that placing cones between graphene and carbon nanotubes could enhance heat dissipation from nano-electronics. The nano-chimneys become better at conducting heat-carrying phonons by spreading out the number of heptagons required by the graphene-to-nanotube transition. Credit: Alex Kutana/Rice University

A Jan. 4, 2016 Rice University news release (also on EurekAlert), which originated the news item, describes the research in more detail,

Heat is transferred through phonons, quasiparticle waves that also transmit sound. The Rice theory offers a strategy to channel damaging heat away from next-generation nano-electronics.

Both graphene and carbon nanotubes consist of six-atom rings, which create a chicken-wire appearance, and both excel at the rapid transfer of electricity and phonons.

But when a nanotube grows from graphene, atoms facilitate the turn by forming heptagonal (seven-member) rings instead. Scientists have determined that forests of nanotubes grown from graphene are excellent for storing hydrogen for energy applications, but in electronics, the heptagons scatter phonons and hinder the escape of heat through the pillars.

The Rice researchers discovered through computer simulations that removing atoms here and there from the two-dimensional graphene base would force a cone to form between the graphene and the nanotube. The geometric properties (aka topology) of the graphene-to-cone and cone-to-nanotube transitions require the same total number of heptagons, but they are more sparsely spaced and leave a clear path of hexagons available for heat to race up the chimney.

“Our interest in advancing new applications for low-dimensional carbon — fullerenes, nanotubes and graphene — is broad,” Yakobson said. “One way is to use them as building blocks to fill three-dimensional spaces with different designs, creating anisotropic, nonuniform scaffolds with properties that none of the current bulk materials have. In this case, we studied a combination of nanotubes and graphene, connected by cones, motivated by seeing such shapes obtained in our colleagues’ experimental labs.”

The researchers tested phonon conduction through simulations of free-standing nanotubes, pillared graphene and nano-chimneys with a cone radius of either 20 or 40 angstroms. The pillared graphene was 20 percent less conductive than plain nanotubes. The 20-angstrom nano-chimneys were just as conductive as plain nanotubes, while 40-angstrom cones were 20 percent better than the nanotubes.

“The tunability of such structures is virtually limitless, stemming from the vast combinatorial possibilities of arranging the elementary modules,” said Alex Kutana, a Rice research scientist and co-author of the study. “The actual challenge is to find the most useful structures given a vast number of possibilities and then make them in the lab reliably.

“In the present case, the fine-tuning parameters could be cone shapes and radii, nanotube spacing, lengths and diameters. Interestingly, the nano-chimneys also act like thermal diodes, with heat flowing faster in one direction than the other,” he said.

Here’s a link to and a citation for the paper,

Nanochimneys: Topology and Thermal Conductance of 3D Nanotube–Graphene Cone Junctions by Ziang Zhang, Alex Kutana, Ajit Roy, and Boris I. Yakobson. J. Phys. Chem. C, Article ASAP DOI: 10.1021/acs.jpcc.6b11350 Publication Date (Web): December 21, 2016

Copyright © 2016 American Chemical Society

This paper is behind a paywall.

Are there any leaders in the ‘graphene race’?

Tom Eldridge, a director and co-founder of Fullerex, has written a Jan. 5, 2017 essay titled: Is China still leading the graphene race? for Nanotechnology Now. Before getting to the essay, here’s a bit more about Fullerex and Tom Eldridge’s qualifications. From Fullerex’s LinkedIn description,

Fullerex is a leading independent broker of nanomaterials and nano-intermediates. Our mission is to support the advancement of nanotechnology in creating radical, transformative and sustainable improvement to society. We are dedicated to achieving these aims by accelerating the commercialisation and usage of nanomaterials across industry and beyond. Fullerex is active in market development and physical trading of advanced materials. We generate demand for nanomaterials across synergistic markets by stimulating innovation with end-users and ensuring robust supply chains are in place to address the growing commercial trade interest. Our end-user markets include Polymers and Polymer Composites, Coatings, Tyre and Rubber, Cementitious Composites, 3D Printing and Printed Electronics, the Energy sector, Lubricating Oils and Functional Fluids. The materials we cover: Nanomaterials: Includes fullerenes, carbon nanotubes and graphene, metal and metal oxide nanoparticles, and organic-inorganic hybrids. Supplied as raw nanopowders or ready-to-use dispersions and concentrates. Nano-intermediates: Producer goods and semi-finished products such as nano-enabled coatings, polymer masterbatches, conductive inks, thermal interface materials and catalysts.

As for Tom Eldridge, here’s more about him, his brother, and the company from the Fullerex About page,

Fullerex was founded by Joe and Tom Eldridge, brothers with a keen interest in nanotechnology and the associated emerging market for nanomaterials.

Joe has a strong background in trading with nearly 10 years’ experience as a stockbroker, managing client accounts for European Equities and FX. At University he read Mathematics at Imperial College London gaining a BSc degree and has closely followed the markets for disruptive technologies and advanced materials for a number of years.

Tom worked in the City of London for 7 years in commercial roles throughout his professional career, with an expertise in market data, financial and regulatory news. In his academic background, he earned a BSc degree in Physics and Philosophy at Kings College London and is a member of the Institute of Physics.

As a result, Fullerex has the strong management composition that allows the company to support the growth of the nascent and highly promising nanomaterials industry. Fullerex is a flexible company with drive, enthusiasm and experience, committed to aiding the development of this market.

Getting back to the matter at hand, that’s a rather provocative title for Tom Eldridge’s essay,. given that he’s a Brit and (I believe) the Brits viewed themselves as leaders in the ‘graphene race’ but he offers a more nuanced analysis than might be expected from the title. First, the patent landscape (from Eldridge’s Jan. 5, 2017 essay),

As competition to exploit the “wonder material” has intensified around the world, detailed reports have so far been published which set out an in-depth depiction of the global patent landscape for graphene, notably from CambridgeIP and the UK Intellectual Property Office, in 2013 and 2015 respectively. Ostensibly the number of patents and patent applications both indicated that China was leading the innovation in graphene technology. However, on closer inspection it became less clear as to how closely the patent figures themselves reflect actual progress and whether this will translate into real economic impact. Some of the main reasons to be doubtful included:

– 98% of the Chinese patent applications only cover China, so therefore have no worldwide monopoly.
– A large number of the Chinese patents are filed in December, possibly due to demand to meet patent quotas. The implication being that the patent filings follow a politically driven agenda, rather than a purely innovation or commercially driven agenda.
– In general, inventors could be more likely to file for patent protection in some countries rather than others e.g. for tax purposes. Which therefore does not give a truly accurate picture of where all the actual research activity is based.
– Measuring the proportion of graphene related patents to overall patents is more indicative of graphene specialisation, which shows that Singapore has the largest proportion of graphene patents, followed by China, then South Korea.

(Intellectual Property Office, 2015), (Ellis, 2015), (CambridgeIP, 2013)

Then, there’s the question of production,

Following the recent launch of the latest edition of the Bulk Graphene Pricing Report, which is available exclusively through The Graphene Council, Fullerex has updated its comprehensive list of graphene producers worldwide, and below is a summary of the number of graphene producers by country in 2017.

Summary Table Showing the Number of Graphene Producers by Country and Region

The total number of graphene producers identified is 142, across 27 countries. This research expands upon previous surveys of the graphene industry, such as the big data analysis performed by Nesta in 2015 (Shapira, 2015). The study by Nesta [formerly  NESTA, National Endowment for Science, Technology and the Arts) is an independent charity that works to increase the innovation capacity of the UK; see Wikipedia here for more about NESTA] revealed 65 producers throughout 16 countries but was unable to glean accurate data on producers in Asia, particularly China.

As we can now see however from the data collected by Fullerex, China has the largest number of graphene producers, followed by the USA, and then the UK.

In addition to having more companies active in the production and sale of graphene than any other country, China also holds about 2/3rds of the global production capacity, according to Fullerex.

Eldridge goes on to note that the ‘graphene industry’ won’t truly grow and develop until there are substantive applications for the material. He also suggests taking another look at the production figures,

As with the patent landscape, rather than looking at the absolute figures, we can review the numbers in relative terms. For instance, if we normalise to account for the differences in the size of each country, by looking at the number of producers as a proportion of GDP, we see the following: Spain (7.18), UK (4.48), India (3.73), China (3.57), Canada (3.28) [emphasis mine], USA (1.79) (United Nations, 2013).

Unsurprisingly, each leading country has a national strategy for economic development which involves graphene prominently.

For instance, The Spanish Council for Scientific Research has lent 9 of its institutes along with 10 universities and other public R&D labs involved in coordinating graphene projects with industry.

The Natural Sciences and Engineering Research Council of Canada [NSERC] has placed graphene as one of five research topics in its target area of “Advanced Manufacturing” for Strategic Partnership Grants.

The UK government highlights advanced materials as one of its Eight Great Technologies, within which graphene is a major part of, having received investment for the NGI and GEIC buildings, along with EPSRC and Innovate UK projects. I wrote previously about the UK punching above its weight in terms of research, ( http://fullerex.com/index.php/articles/130-the-uk-needs-an-industrial-revolution-can-graphene-deliver/ ) but that R&D spending relative to GDP was too low compared to other developed nations. It is good to see that investment into graphene production in the UK is bucking that trend, and we should anticipate this will provide a positive economic outcome.

Yes, I’m  particularly interested in the fact Canada becomes more important as a producer when the numbers are relative but it is interesting to compare the chart with Eldridge’s text and to note how importance shifts depending on what numbers are being considered.

I recommend reading Eldridge’s piece in its entirety.

A few notes about graphene in Canada

By the way, the information in Eldridge’s essay about NSERC’s placement of graphene as a target area for grants is news to me. (As I have often noted here, I get more information about the Canadian nano scene from international sources than I do from our national sources.)

Happily I do get some home news such as a Jan. 5, 2017 email update from Lomiko Metals, a Canadian junior exploration company focused on graphite and lithium. The email provides the latest information from the company (as I’m not an expert in business or mining this is not an endorsement),

On December 13, 2016 we were excited to announce the completion of our drill program at the La Loutre flake graphite property. We received very positive results from our 1550 meter drilling program in 2015 in the area we are drilling now. In that release I stated, “”The intercepts of multiple zones of mineralization in the Refractory Zone where we have reported high grade intercepts previously is a very promising sign. The samples have been rushed to the ALS Laboratory for full assay testing,” We hope to have the results of those assays shortly.

December 16, 2016 Lomiko announced a 10:1 roll back of our shares. We believe that this roll back is important as we work towards securing long term equity financing for the company. Lomiko began trading on the basis of the roll back on December 19.

We believe that Graphite has a bright future because of the many new products that will rely on the material. I have attached a link to a video on Lomiko, Graphite and Graphene.  

https://youtu.be/Y–Y_Ub6oC4

January 3, 2017 Lomiko announced the extension and modification of its option agreements with Canadian Strategic Metals Inc. for the La Loutre and Lac des Iles properties. The effect of this extension is to give Lomiko additional time to complete the required work under the agreements.

Going forward Lomiko is in a much stronger position as the result of our share roll back. Potential equity funders who are very interested in our forthcoming assay results from La Loutre and the overall prospects of the company, have been reassured by our share consolidation.

Looking forward to 2017, we anticipate the assays of the La Loutre drilling to be delivered in the next 90 days, sooner we hope. We also anticipate additional equity funding will become available for the further exploration and delineation of the La Loutre and Lac des Iles properties and deposits.

More generally, we are confident that the market for large flake graphite will become firmer in 2017. Lomiko’s strategy of identifying near surface, ready to mine, graphite nodes puts us in the position to take advantage of improvements in the graphite price without having to commit large sums to massive mine development. As we identify and analyze the graphite nodes we are finding we increase the potential resources of the company. 2017 should see significantly improved resource estimates for Lomiko’s properties.

As I wasn’t familiar with the term ‘roll back of shares’, I looked it up and found this in an April 18, 2012 posting by Dudley Pierce Baker on kitco.com,

As a general rule, we hate to see an announcement of a share rollback, however, there exceptions which we cover below. Investors should always be aware that if a company has, say over 150 million shares outstanding, in our opinion, it is a potential candidate for a rollback and the announcement should not come as a surprise.

Weak markets, a low share price, a large number of shares outstanding, little or no cash and you have a company which is an idea candidate for a rollback.

The basic concept of a rollback or consolidation in a company’s shares is rather simple.

We are witnessing a few cases of rollbacks not with the purpose of raising more money but rather to facilitate the listing of the company’s shares on the NYSE [New York Stock Exchange] Amex.

I have no idea what situation Lomiko finds itself in but it should be noted that graphere research has been active since 2004 when the first graphene sheets were extracted from graphite. This is a relatively new field of endeavour and Lomiko (along with other companies) is in the position of pioneering the effort here in Canada. That said, there are many competitors to graphene and major international race to commercialize nanotechnology-enabled products.

Are there any leaders in the ‘graphene race?

Getting back to the question in the headline, I don’t think there are any leaders at the moment. No one seems to have what they used to call “a killer app,” that one application/product that everyone wants and which drive demand for graphene.

Graphene and silly putty combined to create ultra sensitive sensors

One of my favourite kinds of science story is the one where scientists turn to a children’s toy for their research. In this case, it’s silly putty. Before launching into the science part of this story, here’s more about silly putty from its Wikipedia entry (Note: A ll links have been removed),

During World War II, Japan invaded rubber-producing countries as they expanded their sphere of influence in the Pacific Rim. Rubber was vital for the production of rafts, tires, vehicle and aircraft parts, gas masks, and boots. In the U.S., all rubber products were rationed; citizens were encouraged to make their rubber products last until the end of the war and to donate spare tires, boots, and coats. Meanwhile, the government funded research into synthetic rubber compounds to attempt to solve this shortage.[10]

Credit for the invention of Silly Putty is disputed[11] and has been attributed variously to Earl Warrick,[12] of the then newly formed Dow Corning; Harvey Chin; and James Wright, a Scottish-born inventor working for General Electric in New Haven, Connecticut.[13] Throughout his life, Warrick insisted that he and his colleague, Rob Roy McGregor, received the patent for Silly Putty before Wright did; but Crayola’s history of Silly Putty states that Wright first invented it in 1943.[10][14][15] Both researchers independently discovered that reacting boric acid with silicone oil would produce a gooey, bouncy material with several unique properties. The non-toxic putty would bounce when dropped, could stretch farther than regular rubber, would not go moldy, and had a very high melting temperature. However, the substance did not have all the properties needed to replace rubber.[1]

In 1949 toy store owner Ruth Fallgatter came across the putty. She contacted marketing consultant Peter C.L. Hodgson (1912-1976).[16] The two decided to market the bouncing putty by selling it in a clear case. Although it sold well, Fallgatter did not pursue it further. However, Hodgson saw its potential.[1][3]

Already US$12,000 in debt, Hodgson borrowed US$147 to buy a batch of the putty to pack 1 oz (28 g) portions into plastic eggs for US$1, calling it Silly Putty. Initially, sales were poor, but after a New Yorker article mentioned it, Hodgson sold over 250,000 eggs of silly putty in three days.[3] However, Hodgson was almost put out of business in 1951 by the Korean War. Silicone, the main ingredient in silly putty, was put on ration, harming his business. A year later the restriction on silicone was lifted and the production of Silly Putty resumed.[17][9] Initially, it was primarily targeted towards adults. However, by 1955 the majority of its customers were aged 6 to 12. In 1957, Hodgson produced the first televised commercial for Silly Putty, which aired during the Howdy Doody Show.[18]

In 1961 Silly Putty went worldwide, becoming a hit in the Soviet Union and Europe. In 1968 it was taken into lunar orbit by the Apollo 8 astronauts.[17]

Peter Hodgson died in 1976. A year later, Binney & Smith, the makers of Crayola products, acquired the rights to Silly Putty. As of 2005, annual Silly Putty sales exceeded six million eggs.[19]

Silly Putty was inducted into the National Toy Hall of Fame on May 28, 2001. [20]

I had no idea silly putty had its origins in World War II era research. At any rate, it’s made its way back to the research lab to be united with graphene according to a Dec. 8, 2016 news item  on Nanowerk,

Researchers in AMBER, the Science Foundation Ireland-funded materials science research centre, hosted in Trinity College Dublin, have used graphene to make the novelty children’s material silly putty® (polysilicone) conduct electricity, creating extremely sensitive sensors. This world first research, led by Professor Jonathan Coleman from TCD and in collaboration with Prof Robert Young of the University of Manchester, potentially offers exciting possibilities for applications in new, inexpensive devices and diagnostics in medicine and other sectors.

A Dec. 9, 2016 Trinity College Dublin press release (also on EurekAlert), which originated the news item, describes their ‘G-putty’ in more detail,

Prof Coleman, Investigator in AMBER and Trinity’s School of Physics along with postdoctoral researcher Conor Boland, discovered that the electrical resistance of putty infused with graphene (“G-putty”) was extremely sensitive to the slightest deformation or impact. They mounted the G-putty onto the chest and neck of human subjects and used it to measure breathing, pulse and even blood pressure. It showed unprecedented sensitivity as a sensor for strain and pressure, hundreds of times more sensitive than normal sensors. The G-putty also works as a very sensitive impact sensor, able to detect the footsteps of small spiders. It is believed that this material will find applications in a range of medical devices.

Prof Coleman said, “What we are excited about is the unexpected behaviour we found when we added graphene to the polymer, a cross-linked polysilicone. This material as well known as the children’s toy silly putty. It is different from familiar materials in that it flows like a viscous liquid when deformed slowly but bounces like an elastic solid when thrown against a surface. When we added the graphene to the silly putty, it caused it to conduct electricity, but in a very unusual way. The electrical resistance of the G-putty was very sensitive to deformation with the resistance increasing sharply on even the slightest strain or impact. Unusually, the resistance slowly returned close to its original value as the putty self-healed over time.”

He continued, “While a common application has been to add graphene to plastics in order to improve the electrical, mechanical, thermal or barrier properties, the resultant composites have generally performed as expected without any great surprises. The behaviour we found with G-putty has not been found in any other composite material. This unique discovery will open up major possibilities in sensor manufacturing worldwide.”

Dexter Johnson in a Dec. 14, 2016 posting on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers]) puts this research into context,

For all the talk and research that has gone into exploiting graphene’s pliant properties for use in wearable and flexible electronics, most of the polymer composites it has been mixed with to date have been on the hard and inflexible side.

It took a team of researchers in Ireland to combine graphene with the children’s toy Silly Putty to set the nanomaterial community ablaze with excitement. The combination makes a new composite that promises to make a super-sensitive strain sensor with potential medical diagnostic applications.

“Ablaze with excitement,” eh? As Dexter rarely slips into hyperbole, this must be a big deal.

The researchers have made this video available,

For the very interested, here’s a link to and a citation for the paper,

Sensitive electromechanical sensors using viscoelastic graphene-polymer nanocomposites by Conor S. Boland, Umar Khan, Gavin Ryan, Sebastian Barwich, Romina Charifou, Andrew Harvey, Claudia Backes, Zheling Li, Mauro S. Ferreira, Matthias E. Möbius, Robert J. Young, Jonathan N. Coleman. Science  09 Dec 2016: Vol. 354, Issue 6317, pp. 1257-1260 DOI: 10.1126/science.aag2879

This paper is behind a paywall.

A new graphene-based contrast agent for magnetic resonance imaging (MRI)

After teaching a continuing studies course on bioelectronics for Simon Fraser University (Vancouver, Canada), I’ve developed a mild interest in magnetic resonance imaging and contrast agents which this Nov. 11, 2016 news item on phys.org satisfies,

Graphene, the atomically thin sheets of carbon that materials scientists are hoping to use for everything from nanoelectronics and aircraft de-icers to batteries and bone implants, may also find use as contrast agents for magnetic resonance imaging (MRI), according to new research from Rice University.

“They have a lot of advantages compared with conventionally available contrast agents,” Rice researcher Sruthi Radhakrishnan said of the graphene-based quantum dots she has studied for the past two years. “Virtually all of the widely used contrast agents contain toxic metals, but our material has no metal. It’s just carbon, hydrogen, oxygen and fluorine, and in all of our tests so far it has shown no signs of toxicity.”

The initial findings for Rice’s nanoparticles—disks of graphene that are decorated with fluorine atoms and simply organic molecules that make them magnetic—are described in a new paper in the journal Particle and Particle Systems characterization.

A Nov. 10, 2016 Rice University (Texas, US) news release, which originated the news item, describes the work in more detail,

Pulickel Ajayan, the Rice materials scientist who is directing the work, said the fluorinated graphene oxide quantum dots could be particularly useful as MRI contrast agents because they could be targeted to specific kinds of tissues.

“There are tried-and-true methods for attaching biomarkers to carbon nanoparticles, so one could easily envision using these quantum dots to develop tissue-specific contrast agents,” Ajayan said. “For example, this method could be used to selectively target specific types of cancer or brain lesions caused by Alzheimer’s disease. That kind of specificity isn’t available with today’s contrast agents.”

MRI scanners make images of the body’s internal structures using strong magnetic fields and radio waves. As diagnostic tests, MRIs often provide greater detail than X-rays without the harmful radiation, and as a result, MRI usage has risen sharply over the past decade. More than 30 million MRIs are performed annually in the U.S.

Radhakrishnan said her work began in 2014 after Ajayan’s research team found that adding fluorine to either graphite or graphene caused the materials to show up well on MRI scans.

All materials are influenced by magnetic fields, including animal tissues. In MRI scanners, a powerful magnetic field causes individual atoms throughout the body to become magnetically aligned. A pulse of radio energy is used to disrupt this alignment, and the machine measures how long it takes for the atoms in different parts of the body to become realigned. Based on these measures, the scanner can build up a detailed image of the body’s internal structures.

MRI contrast agents shorten the amount of time it takes for tissues to realign and significantly improve the resolution of MRI scans. Almost all commercially available contrast agents are made from toxic metals like gadolinium, iron or manganese.

“We worked with a team from MD Anderson Cancer Center to assess the cytocompatibility of fluorinated graphene oxide quantum dots,” Radhakrishnan said. “We used a test that measures the metabolic activity of cell cultures and detects toxicity as a drop in metabolic activity. We incubated quantum dots in kidney cell cultures for up to three days and found no significant cell death in the cultures, even at the highest concentrations.”

The fluorinated graphene oxide quantum dots Radhakrishnan studies can be made in less than a day, but she spent two years perfecting the recipe for them. She begins with micron-sized sheets of graphene that have been fluorinated and oxidized. When these are added to a solvent and stirred for several hours, they break into smaller pieces. Making the material smaller is not difficult, but the process for making small particles with the appropriate magnetic properties is exacting. Radhakrishnan said there was no “eureka moment” in which she suddenly achieved the right results by stumbling on the best formula. Rather, the project was marked by incremental improvements through dozens of minor alterations.

“It required a lot of optimization,” she said. “The recipe matters a lot.”

Radhakrishnan said she plans to continue studying the material and hopes to eventually have a hand in proving that it is safe and effective for clinical MRI tests.

“I would like to see it applied commercially in clinical ways because it has a lot of advantages compared with conventionally available agents,” she said.

Here’s a link to and a citation for the paper,

Metal-Free Dual Modal Contrast Agents Based on Fluorographene Quantum Dots by Sruthi Radhakrishnan, Atanu Samanta, Parambath M. Sudeep, Kiersten L. Maldonado, Sendurai A. Mani, Ghanashyam Acharya, Chandra Sekhar Tiwary, Abhishek K. Singh, and Pulickel M. Ajayan. Particle & Particle Systems Characterization DOI: 10.1002/ppsc.201600221 Version of Record online: 21 OCT 2016

This paper is behind a paywall.

Boron nitride-graphene hybrid nanostructures could lead to next generation ‘green’ cars

An Oct. 24, 2016 phys.org news item describes research which may lead to improved fuel storage in ‘green’ cars,

Layers of graphene separated by nanotube pillars of boron nitride may be a suitable material to store hydrogen fuel in cars, according to Rice University scientists.

The Department of Energy has set benchmarks for storage materials that would make hydrogen a practical fuel for light-duty vehicles. The Rice lab of materials scientist Rouzbeh Shahsavari determined in a new computational study that pillared boron nitride and graphene could be a candidate.

An Oct. 24, 2016 Rice University news release (also on EurekAlert), which originated the news item, provides more detail (Note: Links have been removed),

Shahsavari’s lab had already determined through computer models how tough and resilient pillared graphene structures would be, and later worked boron nitride nanotubes into the mix to model a unique three-dimensional architecture. (Samples of boron nitride nanotubes seamlessly bonded to graphene have been made.)

Just as pillars in a building make space between floors for people, pillars in boron nitride graphene make space for hydrogen atoms. The challenge is to make them enter and stay in sufficient numbers and exit upon demand.

In their latest molecular dynamics simulations, the researchers found that either pillared graphene or pillared boron nitride graphene would offer abundant surface area (about 2,547 square meters per gram) with good recyclable properties under ambient conditions. Their models showed adding oxygen or lithium to the materials would make them even better at binding hydrogen.

They focused the simulations on four variants: pillared structures of boron nitride or pillared boron nitride graphene doped with either oxygen or lithium. At room temperature and in ambient pressure, oxygen-doped boron nitride graphene proved the best, holding 11.6 percent of its weight in hydrogen (its gravimetric capacity) and about 60 grams per liter (its volumetric capacity); it easily beat competing technologies like porous boron nitride, metal oxide frameworks and carbon nanotubes.

At a chilly -321 degrees Fahrenheit, the material held 14.77 percent of its weight in hydrogen.

The Department of Energy’s current target for economic storage media is the ability to store more than 5.5 percent of its weight and 40 grams per liter in hydrogen under moderate conditions. The ultimate targets are 7.5 weight percent and 70 grams per liter.

Shahsavari said hydrogen atoms adsorbed to the undoped pillared boron nitride graphene, thanks to  weak van der Waals forces. When the material was doped with oxygen, the atoms bonded strongly with the hybrid and created a better surface for incoming hydrogen, which Shahsavari said would likely be delivered under pressure and would exit when pressure is released.

“Adding oxygen to the substrate gives us good bonding because of the nature of the charges and their interactions,” he said. “Oxygen and hydrogen are known to have good chemical affinity.”

He said the polarized nature of the boron nitride where it bonds with the graphene and the electron mobility of the graphene itself make the material highly tunable for applications.

“What we’re looking for is the sweet spot,” Shahsavari said, describing the ideal conditions as a balance between the material’s surface area and weight, as well as the operating temperatures and pressures. “This is only practical through computational modeling, because we can test a lot of variations very quickly. It would take experimentalists months to do what takes us only days.”

He said the structures should be robust enough to easily surpass the Department of Energy requirement that a hydrogen fuel tank be able to withstand 1,500 charge-discharge cycles.

Shayeganfar [Farzaneh Shayeganfar], a former visiting scholar at Rice, is an instructor at Shahid Rajaee Teacher Training University in Tehran, Iran.

 

Caption: Simulations by Rice University scientists show that pillared graphene boron nitride may be a suitable storage medium for hydrogen-powered vehicles. Above, the pink (boron) and blue (nitrogen) pillars serve as spacers for carbon graphene sheets (gray). The researchers showed the material worked best when doped with oxygen atoms (red), which enhanced its ability to adsorb and desorb hydrogen (white). Credit: Lei Tao/Rice University

Caption: Simulations by Rice University scientists show that pillared graphene boron nitride may be a suitable storage medium for hydrogen-powered vehicles. Above, the pink (boron) and blue (nitrogen) pillars serve as spacers for carbon graphene sheets (gray). The researchers showed the material worked best when doped with oxygen atoms (red), which enhanced its ability to adsorb and desorb hydrogen (white). Credit: Lei Tao/Rice University

Here’s a link to and a citation for the paper,

Oxygen and Lithium Doped Hybrid Boron-Nitride/Carbon Networks for Hydrogen Storage by Farzaneh Shayeganfar and Rouzbeh Shahsavari. Langmuir,  DOI: 10.1021/acs.langmuir.6b02997 Publication Date (Web): October 23, 2016

Copyright © 2016 American Chemical Society

This paper is behind a paywall.

I last featured research by Shayeganfar and  Shahsavari on graphene and boron nitride in a Jan. 14, 2016 posting.