A graphene container system for manufacturing has been developed by GrapheneCA. The 40-foot containers are designed specifically for industrial producers and high-tech applications of graphene.
A graphene container system for manufacturing has been developed by GrapheneCA. The 40-foot containers are designed specifically for industrial producers and high-tech applications of graphene.
|Researchers in China have demonstrated a graphene nanocomposite foam-based water harvesting system to harvest water from air. The team reports their findings in ACS Applied Materials & Interfaces (“Superelastic Graphene Nanocomposite for High Cycle-Stability Water Capture-Release under Sunlight”).|
|Only 30% of all freshwater on the planet is not locked up in ice caps or glaciers (not for much longer, though). Of that, some 20% is in areas too remote for humans to access and of the remaining 80% about three-quarters comes at the wrong time and place – in monsoons and floods – and is not always captured for use by people. The remainder is less than 0.08 of 1% of the total water on the planet (read more: “Nanotechnology and water treatment“)|
|An abundance of water equivalent to about 10% of the total freshwater in lakes exists in the earth atmosphere, which can be a non-negligible freshwater resource to fight against the water shortage.|
|That’s where the graphene nanocomposite foam comes in: The foam realizes water harvesting through a capture-release cycle:|
|1) the capture process is composed of moisture adsorption from air by lithium chloride (LiCl) and water preservation by poly(vinyl alcohol) (PVA) and|
|2) the release relies on the solar-to-thermal transformer, reduced graphene oxide (rGO), to facilitate evaporation. In addition, polyimide is employed as a substrate material for the purpose of 3D porous structure formation and mechanical property enhancement.
Photograph, schematic diagram, and SEM images of the graphene nanocomposite foam. (a) Photograph of the graphene nanocomposite foam. (b) Schematic diagram of the graphene nanocomposite foam. Foam was prepared through a three-step process: freeze-drying, thermal annealing, and hydrophilic treatment. rGO/PI nanosheet, as the basic unit, can achieve the water harvesting capture-release cycle without additional energy input. (c) SEM image presents a porous structure of the rGO/PI foam without hydrophilic treatment. (d) Magnified SEM image of the rGO/PI foam without hydrophilic treatment to show a relatively smooth surface of the nanosheet. (e) SEM image of the graphene nanocomposite foam after hydrophilic treatment. (f) Magnified SEM image of the hydrophilic rGO/PI foam with bumped nanostructures. (g) Schematic diagram of the water vapor capture-release cycle.
LiCl and PVA were responsible for the water capture and water storage, respectively. Adsorbed water was stored as crystallized water in LiCl hydrates and the free water molecules were restrained by hydroxyl groups on PVA through the hydrogen bond, which led to the transformation of the nanosheet from dry status to wet status. Opposite procedure, from wet status to dry status, was realized by the rGO converting the solar energy to thermal energy to facilitate water evaporation under irradiation. (Reprinted with permission by American Chemical Society) (click on image to enlarge)
|The as-fabricated foam can adsorb water up to 2.87 g per gram in 24 hours at a relative humidity of 90% and a temperature of 30°C, and release almost all the uptake water when it is exposed under a flux of 1 sun (1000 W per square meter, equal to the light intensity of natural sunlight) for 3 hours.|
|At the same time, the functional foam shows superelasticity, lightweight, and remarkable reusability, thus revealing its possibility to practical use.|
|The researchers write that, even though the rGO/PI nanocomposite foam can harvest freshwater from air, it is essential to enhance water harvesting efficiency.|
|“Another big challenge impedes the water harvesting system utilization to explore a more cost-effective way to prepare the products,” they conclude. “Though the three-step synthesis method and the composition of the foam have been optimized, it is still necessary to reduce the cost and increase the fabrication efficiency. Meanwhile, environmentally friendly materials are recommended, which would take the water harvesting system one step further to commercial application and large-scale production.”|
|By Michael Berger – Nanowerk|
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Nano Enabled Batteries and Super Capacitors
Tenka Energy, Inc. Building Ultra-Thin Energy Dense SuperCaps and NexGen Nano-Enabled Pouch & Cylindrical Batteries – Energy Storage Made Small and POWERFUL!
Lithium batteries are what allow electric vehicles to travel several hundred miles on one charge. Their capacity for energy storage is well known, but so is their tendency to occasionally catch on fire—an occurrence known to battery researchers as “thermal runaway.” These fires occur most frequently when the batteries overheat or cycle rapidly. With more and more electric vehicles on the road each year, battery technology needs to adapt to reduce the likelihood of these dangerous and catastrophic fires.
Researchers from the University of Illinois at Chicago College of Engineering report that graphene—wonder material of the 21st century—may take the oxygen out of lithium battery fires. They report their findings in the journal Advanced Functional Materials.
The reasons lithium batteries catch fire include rapid cycling or charging and discharging, and high temperatures in the battery. These conditions can cause the cathode inside the battery—which in the case of most lithium batteries is a lithium-containing oxide, usually lithium cobalt oxide—to decompose and release oxygen. If the oxygen combines with other flammable products given off through decomposition of the electrolyte under high enough heat, spontaneous combustion can occur.
“We thought that if there was a way to prevent the oxygen from leaving the cathode and mixing with other flammable products in the battery, we could reduce the chances of a fire occurring,” said Reza Shahbazian-Yassar, associate professor of mechanical and industrial engineering in the UIC College of Engineering and corresponding author of the paper.
It turns out that a material Shahbazian-Yassar is very familiar with provided a perfect solution to this problem. That material is graphene—a super-thin layer of carbon atoms with unique properties. Shahbazian-Yassar and his colleagues previously had used graphene to help modulate lithium buildup on electrodes in lithium metal batteries.
Lithium cobalt oxide particles coated in graphene. Credit: Reza Shahbazian-Yassar.
Shahbazian-Yassar and his colleagues knew that graphene sheets are impermeable to oxygen atoms. Graphene is also strong, flexible and can be made to be electrically conductive. Shahbazian-Yassar and Soroosh Sharifi-Asl, a graduate student in mechanical and industrial engineering at UIC and lead author of the paper, thought that if they wrapped very small particles of the lithium cobalt oxide cathode of a lithium battery in graphene, it might prevent oxygen from escaping.
First, the researchers chemically altered the graphene to make it electrically conductive. Next, they wrapped the tiny particles of lithium cobalt oxide cathode electrode in the conductive graphene.
When they looked at the graphene-wrapped lithium cobalt oxide particles using electron microscopy, they saw that the release of oxygen under high heat was reduced significantly compared with unwrapped particles.
Next, they bound together the wrapped particles with a binding material to form a usable cathode, and incorporated it into a lithium metal battery. When they measured released oxygen during battery cycling, they saw almost no oxygen escaping from cathodes even at very high voltages. The lithium metal battery continued to perform well even after 200 cycles.
“The wrapped cathode battery lost only about 14% of its capacity after rapid cycling compared to a conventional lithium metal battery where performance was down about 45% under the same conditions,” Sharifi-Asl said.
“Graphene is the ideal material for blocking the release of oxygen into the electrolyte,” Shahbazian-Yassar said. “It is impermeable to oxygen, electrically conductive, flexible, and is strong enough to withstand conditions within the battery. It is only a few nanometers thick so there would be no extra mass added to the battery. Our research shows that its use in the cathode can reliably reduce the release of oxygen and could be one way that the risk for fire in these batteries—which power everything from our phones to our cars—could be significantly reduced.”
Graphene, a new material with applications in biomedical technology, electronics, composites, energy and sensors, may soon help send rockets to space.
A new propellant formulation method to use graphene foams – material used in electronics, optics and energy devices – to power spacecraft is being developed in Purdue University’s Maurice J. Zucrow Laboratories, which is the largest academic propulsion lab in the world. The research is showing success at increasing burn rate of solid propellants that are used to fuel rockets and spacecraft.
“Our propulsion and physics researchers came together to focus on a material that has not previously been used in rocket propulsion, and it is demonstrating strong results,” said Li Qiao, an associate professor of aeronautics and astronautics in Purdue’s College of Engineering.
The research team, led by Qiao, developed methods of making and using compositions with solid fuel loaded on highly conductive, highly porous graphene foams for enhanced burn rates for the loaded solid fuel. They wanted to maximize the catalytic effect of metal oxide additives commonly used in solid propellant to enhance decomposition.
Qiao said the graphene foam works well for solid propellants because it is super lightweight and highly porous, which means it has many holes in which scientists can pour fuel to help ignite a rocket launch.
The graphene foam has a 3-D, interconnected structure to allow a more efficient thermal transport pathway for heat to quickly spread and ignite the propellant.
“Our patented technology provides higher performance that is especially important when looking at areas such as hypersonics,” Qiao said. “Our tests showed a burn rate enhancement of nine times the normal, using functionalized graphene foam structures.”
Qiao said the Purdue graphene foam discovery has applications for energy conversion devices and missile defense systems, along with other areas where tailoring nanomaterials for specific outcomes may be useful.
From MIT Technology Review March 2019
Researchers at Swinburne, the University of Sydney and Australian National University have collaborated to develop a solar absorbing, ultra-thin graphene-based film with unique properties that has great potential for use in solar thermal energy harvesting.
The 90 nanometre material is said to be a 1000 times finer than a human hair and is able to rapidly heat up to 160°C under natural sunlight in an open environment.
The team stated that this new graphene-based material may also open new avenues in:
The researchers have developed a 2.5cm x 5cm working prototype to demonstrate the photo-thermal performance of the graphene-based metamaterial absorber. They have also proposed a scalable manufacturing strategy to fabricate the proposed graphene-based absorber at low cost.
“This is among many graphene innovations in our group,” says Professor Baohua Jia, Research Leader, Nanophotonic Solar Technology, in Swinburne’s Center for Micro-Photonics.
“In this work, the reduced graphene oxide layer and grating structures were coated with a solution and fabricated by a laser nanofabrication method, respectively, which are both scalable and low cost.”
“Our cost-effective and scalable graphene absorber is promising for integrated, large-scale applications that require polarisation-independent, angle insensitive and broad bandwidth absorption, such as energy-harvesting, thermal emitters, optical interconnects, photodetectors and optical modulators,” says first author of this research paper, Dr Han Lin, Senior Research Fellow in Swinburne’s Center for Micro-Photonics.
“Fabrication on a flexible substrate and the robustness stemming from graphene make it suitable for industrial use,” Dr Keng-Te Lin, another author, added.
“The physical effect causing this outstanding absorption in such a thin layer is quite general and thereby opens up a lot of exciting applications,” says Dr Bjorn Sturmberg, who completed his PhD in physics at the University of Sydney in 2016 and now holds a position at the Australian National University.
“The result shows what can be achieved through collaboration between different universities, in this case with the University of Sydney and Swinburne, each bringing in their own expertise to discover new science and applications for our science,” says Professor Martijn de Sterke, Director of the Institute of Photonics and Optical Science.
“Through our collaboration we came up with a very innovative and successful result. We have essentially developed a new class of optical material, the properties of which can be tuned for multiple uses.”
Scientists from Manchester University, the Ulsan National Institute of Science & Technology and the Korea Institute of Science and Technology have developed a novel technology, which combines the fabrication procedures of planar and vertical heterostructures in order to assemble graphene-based single-electron transistors.
In the study, it was demonstrated that high-quality graphene quantum dots (GQDs), regardless of whether they were ordered or randomly distributed, could be successfully synthesized in a matrix of monolayer hexagonal boron nitride (hBN).
Here, the growth of GQDs within the layer of hBN was shown to be catalytically supported by the platinum (Pt) nanoparticles distributed in-between the hBN and supporting oxidised silicon (SiO2) wafer, when the whole structure was treated by the heat in the methane gas (CH4). It was also shown, that due to the same lattice structure (hexagonal) and small lattice mismatch (~1.5%) of graphene and hBN, graphene islands grow in the hBN with passivated edge states, thereby giving rise to the formation of defect-less quantum dots embedded in the hBN monolayer.
Such planar heterostructures incorporated by means of standard dry-transfer as mid-layers into the regular structure of vertical tunnelling transistors (Si/SiO2/hBN/Gr/hBN/GQDs/hBN/Gr/hBN; here Gr refers to monolayer graphene and GQDs refers to the layer of hBN with the embedded graphene quantum dots) were studied through tunnel spectroscopy at low temperatures (3He, 250mK).
The study demonstrated where the manifestation of well-established phenomena of the Coulomb blockade for each graphene quantum dot as a separate single electron transmission channel occurs.
‘Although the outstanding quality of our single electron transistors could be used for the development of future electronics, “This work is most valuable from a technological standpoint as it suggests a new platform for the investigation of physical properties of various materials through a combination of planar and van der Waals heterostructures.” as explained study co-author Davit Ghazaryan, Associate Professor at the HSE Faculty of Physics, and Research Fellow at the Institute of Solid State Physics (RAS)
Talking with SciTech Europa, Professor Novoselov, co-awarded the 2019 Nobel Prize in Physics, for the discovery and isolation of a single atomic layer of carbon for the first time, explores the research into Graphene Flagship and other 2D materials.
At the University of Manchester, UK, in 2004, Professor Sir Kostya Novoselov, along with his colleague Professor Sir Andre Geim, discovered and isolated a single atomic layer of carbon for the first time. The pair received the Nobel Prize in Physics in 2010 in recognition of their breakthrough.
On 28 January 2013, the European Commission announced that, out of the six pilot preparatory actions put forward for the Future and Emerging Technology (FET) Flagships competition, the Graphene Flagship, along with the Human Brain Project, had been selected to receive €1bn in funding over the course of a decade, tasking it with bringing together academic and industrial researchers to take graphene from the realm of academic laboratories into European society, thereby generating economic growth, new jobs, and new opportunities.
In February, SciTech Europa attended the Mobile World Congress in Barcelona, Spain. This event is the world’s largest exhibition for the mobile industry, and where, for the fourth consecutive year, the Graphene Flagship hosted its Graphene Pavilion – this year showcasing over 20 different graphene-based working prototypes and devices that will transform future telecommunications.
At the pavilion, SEQ met with Professor Novoselov to discuss research into graphene and other two dimensional materials, as well as how the Flagship is working to bolster both fundamental research and applications stemming from these advanced materials.
There has been a lot of progress in recent years and, indeed, we are no longer talking only about graphene, but also about many other two dimensional materials as well.
First of all – new applications of graphene is one example of recent developments – we see new applications emerging on an almost monthly basis. Second, there is still a lot of progress being made in fundamental research on graphene and 2D materials. And those fundamental results are being implemented in applications.
In terms of other new 2D materials, there is a lot of activity on ferromagnetic materials.
The basic technology is in place, and so what is important now is for entrepreneurs and SMEs to convert those developments into commercial applications, and, indeed, we need to help them to do so.
The Flagship, of course, has now reached the half way stage, and we therefore need to carefully balance the amount of effort we place on applications with the effort we place on the development of fundamental science, which remains crucial.
Nevertheless, we also need to ensure we are helping companies and industry to introduce this material into real products, and that is actually much more difficult, not least because of the fact that this has not been done at this scale before, and so nobody knows how to do it yet.
It is not necessarily funding that is a problem in in Europe; the challenge comes more in the form of bringing together scientists, entrepreneurs, and funders in the same room, and it is still not clear how to achieve that. There is thus the argument that we need to work more closely with entrepreneurs and we need to grow those entrepreneurs who are working on advanced materials because this is a much more challenging area than, say, ‘.com’ applications.
It is perhaps the mentality that exists around risk taking that needs to change. Bringing together entrepreneurs, scientists, the technology and the money around the same table is a challenge and, as I have mentioned, it needs to be understood that bringing new materials, especially nanomaterials, to market is much more challenging than it is to bring, for example, new software to consumers.
And, of course, the level of required investment is also much larger. Whether we have enough people in Europe who are ready to take this risk is a good question.
Perhaps; there is certainly a sense that Europe needs to work much harder than the USA or South-East Asia. And the reason for that is not only a lack of those willing to take enhanced risks, but also the level and mobility of the available money and, indeed, how soon financiers expect a return on their investment.
I am not sure that we will see a ‘revolution’; the growth in real world applications utilising graphene is, and will continue to be, a gradual introduction. That is not to say, however, that this gradual process won’t speed up a little over time.
And it is great to see that, when it comes to graphene, this introduction, although gradual, is already happening much faster than with any other advanced material that we have seen before. The purpose of the Flagship is to help speed up this process.
This is an example of the sort of issue where the Flagship should take the initiative, because it is not only about graphene; we need to realise that many new nanomaterials are going to play an increasing role in the everyday lives of people, and we need to be prepared for that.
There are a great many regulations which have to be passed when bringing such advanced materials to market, including health and safety and toxicology regulations, and very often these are not very well defined because, quite simply, we have never been in this situation before. It can also be quite expensive to run the necessary projects to investigate things like toxicology, and so it is important for projects like the Flagship to take the initiative and help businesses to overcome these barriers.
I do indeed conduct my own research, and within that graphene is not the largest part. I go beyond graphene and work on many other 2D materials and heterostructures, but it is nevertheless exciting to remember that it was graphene that made all the other materials possible as we work on those heterostructures towards new discoveries.
Professor Sir Kostya Novoselov
Director, National Graphene Institute at the University of Manchester
Member, Strategic Advisory Council, Graphene Flagship
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