Graphene is a 1-atom-thick layer of tightly bonded carbon atoms arranged in a hexagonal lattice. Graphene the world’s first 2D nanomaterial, is widely regarded as the “wonder material” of the 21st century due to the combination of its extraordinary properties. As a single layer of graphite, it is the thinnest material (monoatom thick), transparent, 200 times stronger than steel, yet as flexible as rubber, more conductive than copper, excellent thermal conductor and impermeable to moisture and gases. Graphene is also extraordinarily light at 0.77 mg/m2, which is roughly 1,000 times lighter than 1 m2 of paper. It is fire resistant yet retains heat.
In addition, the material is extremely diverse and can be combined with other elements (including gases and metals) to produce different materials with a range of superior properties. Graphene is enabling revolutionary applications such as bendable touch screen displays, rapid charge batteries, low cost solar cells, extreme high-speed semiconductors, artificial retinas, biosensors, water purification, fuel cell extractors and even for futuristic ideas as a tether for a space elevator. It will enable next generation electronics applications like Terahertz, Novel quantum devices, etc. Product properties such as high electron mobility, permeability and heat resistance has led to its growing usage in flexible radio frequency devices, consumer electronics, supercapacitors, sensors, conductive inks, coatings, composites, etc.
First applications that have reached the market are mechanical properties such as tennis rackets, bicycle and motorcycle helmets, etc. Huawei Technologies Co.’s Mate 20x series marks the first time graphene has been used in a smartphone. Clothing manufacturer Vollebak has produced a jacket made with graphene that can conduct power, store body heat and repel bacteria. Ray-Ban is already using it in sunglasses. Instead of a “miracle material,” graphene is being sprinkled into products “like pixie dust,” says Julia Attwood, an analyst for Bloomberg NEF.
“Then there are optics-related applications. There are optical sensors that measure different body functions that can warn if you are out in the Sun for long and sensors that can differentiate different kinds of kinds of milk from each other,” Jari Kinaret, Professor for Condensed Matter Theory group at the Department of Applied Physics at Chalmers University of Technology said.
There is a worldwide race going for the production and utilization of this ‘miracle material’, among leading nations like USA, China, Australia, UK, Germany and others. In a recent announcement, researchers from Australia have used a graphene-based product to make a water filter that can make highly-polluted seawater drinkable after just one pass.
Graphene’s lightness and strength have been thought to be a potentially good fit for ballistic protection for some time. In military applications, lighter armor material provides for greater mobility and increased range for the same level of protection. Researchers from the University of Massachusetts in Amherst studied the way graphene absorbs kinetic energy and discovered that it might be extremely efficient in preventing bullet penetration.
In separate research, at the City University of New York (CUNY), it was shown that two layers of graphene exhibit a transverse stiffness and hardness comparable to diamond. At room temperature, the two-layer graphene construct was resistant to perforation with a diamond indenter and showed a reversible drop in electrical conductivity through indentation and release. Daimene, as the construct has been dubbed, is as flexible and lightweight as foil but becomes stiff and hard enough to stop a bullet on impact. Experiments and theory both show that this graphite-diamond transition does not occur for more than two layers or for a single graphene layer.
Worldwide Graphene Race
However recently Graphene research has moved from applied university departments to companies evident by surge in graphene-related patents over the last few years – with almost 13,000 graphene-related patents now lodged – the bulk coming from Japan, Korea, the United States and China. The Chinese influence since 2013 has continued to grow and now almost half of all graphene patents worldwide originate from China.
“Although enormous amounts of efforts have been devoted to graphene research, there is still a large gap between academia and industry.” “How to cross the valley of death from research to business is still an open question,” Says Zhu. Companies such as IBM, Samsung, BAE Systems and Dyson have raced to get involved in graphene-related research. Rolls-Royce, the aircraft engine maker, is assessing the possibilities for graphene and was engaged with the Manchester institute.
The Graphene Flagship is a project funded by the European Union. It is a 10-year project and has been operating for more than four years. Today, there are more than 150 partners from more than 23 countries. Out of the 150 partners, about 50 are companies and around 80 are universities and the rest are research institutes. All are working on different aspects to bring graphene from the laboratory to marketplace.
Two British manufacturers unveiled competing plans to raise funds to bring their products to market. Applied Graphene Materials Plc raised about 9 million pounds ($12 million) from a placement of shares with existing investors, while Haydale Graphene Industries Plc is looking for 6 million pounds, the U.K.-based companies said Tuesday in separate statements.
Manchester in partnership with the UAE is developing Graphene Engineering Innovation Centre. Having received half of its £60 million (Dh311.8m) funding from Abu Dhabi’s renewables company Masdar, it is scheduled to open in 2017, The two institutions will focus their joint graphene research on industrial applications for the energy, aerospace and defence sectors.
Zion Market Research has published a new report according to which, global graphene market was valued at USD 32.0 million in 2016 and is expected to reach USD 193.68 million in 2022, growing at a CAGR of 35.0% between 2017 and 2022. With every year that passes, the demand for graphene is climbing steadily, Brian Cox, Professor of Particle Physics at Manchester University believes that graphene has the potential to become a multi-billion or even multi-trillion dollar industry.The key obstacle to the widespread use of graphene today is the high manufacturing cost of high quality graphene.
The China Innovation Alliance of the Graphene Industry (CIAGI) expects China will account for up to 80 per cent of the global graphene industry, which is expected to be worth at least 100 billion yuan. Chinese companies have been aggressive in securing patents for graphene, though they lack blockbuster products compared to international giants such as IBM and Samsung, said Chen.
It has been reported that China holds the largest number of patents on graphene. Now the latest research from Fullerex which reveals the number of active graphene producers in each country, also puts China on top. China is looking to become a world leader in graphene science, with defence applications for the nanocarbon among its top priorities for development. It has newly formed Military Application of Graphene Commission, order to develop the use of graphene in military applications.
Industrial Aviation Material Research Institute of China Aviation Industry Corporation revealed to its reporter on May 27, 2014 that they had obtained the technology for mass production of graphene film and powder and successfully used graphene to make an alloy of graphene and aluminum, the first such alloy in the world, with exceptional qualities for aircraft and spacecraft.
In the future, Graphene is even thought to replace silicon (epitaxial graphene), the ubiquitous material in the present microelectronics industry due to its high mobility charge carriers. Circuits composed of graphene transistors could operate at much higher speeds and consume less energy than those based on silicon, and they could be used in flexible, bendable electronics.
Scientists at Rutgers University-New Brunswick have found a way to control the electrons in graphene, paving the way for the ultra-fast transport of electrons with low loss of energy in novel systems. “This shows we can electrically control the electrons in graphene,” said a professor in Rutgers’ Department of Physics and Astronomy. “In the past, we couldn’t do it. This is the reason people thought that one could not make devices like transistors that require switching with graphene, because their electrons run wild.”
This new work might make it possible to realize a graphene nano-scale transistor, the team said, which would be an important step towards an all-graphene electronics platform. The team managed to control electrons by sending voltage through a microscope with an extremely sharp tip, also the size of one atom, which offers 3-D views of surfaces at the atomic scale.
Researchers at Chalmers University have developed a flexible detector for terahertz frequencies (1000 gigahertz) using graphene transistors on plastic substrates. It is said to be the first of its kind, and can extend the use of terahertz technology to applications that require flexible electronics, like wireless sensor networks and wearable technology.
Foldable touch screens, smartphones
Graphene is an almost completely optically transparent material (transmit up to 97.7% of light), highly conductive, hence would work very well in optoelectronic applications such as LCD touchscreens for smartphones, tablet and desktop computers and televisions and organic light emitting diodes (OLEDs). If we were to replace all the touchscreens worldwide, we need just 60 kilos of graphene because we need only one atomic layer,” Jari Kinaret said.
For example, according to the American Chemical Society, “Touch screens made with graphene as their conductive element could be printed on thin plastic instead of glass, so they would be light and flexible, which could make cell phones as thin as a piece of paper and foldable enough to slip into a pocket. Because of graphene’s incredible strength, these cell phones would be nearly unbreakable.”
Scientists at the University of Sussex have developed a super flexible material by combining graphene with silver nanowires, to create a film which matches the performance of regular screens, but at fraction of the cost. Our latest development does away with the need for the hard glass surface because the silver nanowire-graphene hybrid films we produce are very flexible, said Dr Matthew Large, lead researcher.
“The addition of graphene to the silver nanowire network also increases its ability to conduct electricity by around a factor of ten thousand. “This means we can use a fraction of the amount of silver to get the same, or better, performance. As a result screens will be more responsive and use less power.” Dr Large added: “This paves the way towards one day developing completely flexible devices.”
Chinese company Moxi have developed a phone with a graphene-based screen that is so flexible that it can be worn as a chunky bracelet. Moxi says it will ship 100,000 of the devices for the Chinese market this year at a price that is equivalent to £531 ($776). The first handsets will have a simple black and white screen, but the company has demonstrated a full colour version which is capable of streaming videos.
Solar cells , Batteries and Supercapacitors
It’s incredibly energy efficient and a potentially eco-friendly source of power. MIT researchers found they could generate electric current by shining light on graphene, meaning it could be used to revolutionize solar-power collection.
In the field of batteries, battery electrode materials are significantly improved when enhanced with graphene. Graphene can make batteries that are light, durable and suitable for high capacity energy storage, as well as shorten charging times. It will extend the battery’s life-time. Currently, scientists are working on enhancing the capabilities of lithium ion batteries (by incorporating graphene as an anode) to offer much higher storage capacities with much better longevity and charge rate.
Graphene had the capacity for far greater energy density than that produced by lithium-ion batteries, without the hazardous side effects. The Russian born Australian scientist behind the technology, Victor Volkov, has completed internal laboratory testing of the Al-Graphene-Oxygen battery, which has demonstrated the capacity to deliver significant benefits over lithium-ion technology. For example it has 7.5 times energy density and 30% lighter.
In November 2016, Huawei Technologies unveiled a new graphene-enhanced Li-ion battery that can remain functional at higher temperature (60° as opposed to the existing 50° limit) and offers a longer operation time (double of what can be achieved with previous batteries). To achieve this breakthrough, Huawei incorporated several new technologies including antidecomposition additives in the electrolyte and chemically stabilized single crystal cathodes—and graphene to facilitate heat dissipation. Huawei claims that the graphene reduces the battery’s operating temperature by 5°.
Graphene-based supercapacitors are said to store almost as much energy as lithium-ion batteries, charge and discharge in seconds and maintain all this over tens of thousands of charging cycles. Huawei claims that its new charging technology that works with super-strong and super-conductive Graphene, ensures that batteries can be recharged 10 times faster without any expense of the battery lifetime. At the battery symposium the Chinese smartphone manufacturer demonstrated the recharging of a 3000 mAh battery from 0 to 48% in five minutes. A 600mAh battery was recharged to 68% in just two minutes. For reference; the iPhone 6S has a 1750mAh battery and the Galaxy S6 has a 2550mAh battery.
Skeleton Technologies is Europe’s leading manufacturer of ultracapacitors, uses patented nanoporous carbide-derived carbon, or ‘curved graphene’ to deliver twice the energy density and 5 times the power density offered by other manufacturers. The ultracapacitors also ensure reliability by starting the vehicle in cold conditions or after prolonged periods in storage.
The military also depends on batteries for successful missions and their use is increasing because of increasing digitization of the battlefield. Graphene can either enhance the endurance of the missions for the same weight or, alternatively, the same storage capacity in a lighter package enhancing overall military capability. The weight can be traded for increased range or enhanced protection by addition of armor. In addition, longer battery life decreases likelihood of mission failure from loss of battery power.
Researchers from the University of Belgrade in Serbia have developed world’s first graphene-based condenser microphone that has 15 decibels higher sensitivity than commercial microphones, at frequencies of up to 11 kHz. But model simulations indicate that a far more sensitive graphene microphone is theoretically possible. At 300 layers thick, a graphene vibrating membrane may be able to detects frequencies of up to 1MHz—approximately fifty times higher than the upper limit of human hearing.
Graphene as Superconductor
In Jan 2017, First time researchers have reported superconductivity in the graphene without having to alter it. “It has long been postulated that, under the right conditions, graphene should undergo a superconducting transition, but can’t,” said one of the researchers, Jason Robinson from the University of Cambridge in the UK. Now, he says his team has managed to awaken that ability. And it appears graphene isn’t just a normal superconductor – it could be conducting current with no resistance as a result of an unconfirmed and elusive type of superconductivity called p-wave state.
In 2015, an international research team from Canada and Germany has been able to demonstrate that graphene can be made to behave as a superconductor when it’s doped with lithium atoms. The researchers believe that this new property could lead to a new generation of superconducting nanoscale devices like nanoscale superconducting quantum interference devices and single-electron superconductor quantum dots. The findings could help lead to advanced magnetic sensors for brain scanning, the researchers added.
Graphene will enable sensors that are smaller and lighter – providing endless design possibilities. They will also be more sensitive and able to detect smaller changes in matter, work more quickly and eventually even be less expensive than traditional sensors.
Graphene is thought to become especially widespread in biosensors and diagnostics. The large surface area of graphene can enhance the surface loading of desired biomolecules, and excellent conductivity and small band gap can be beneficial for conducting electrons between biomolecules and the electrode surface. Biosensors can be used, among other things, for the detection of a range of analytes like glucose, glutamate, cholesterol, hemoglobin and more. Graphene also has significant potential for enabling the development of electrochemical biosensors, based on direct electron transfer between the enzyme and the electrode surface.
Some graphene-based sensor designs contain a Field Effect Transistor (FET) with a graphene channel. Upon detection of the targeted analyte’s binding, the current through the transistor changes, which sends a signal that can be analyzed to determine several variables.
Physicists from the Moscow Institute of Physics and Technology (MIPT) have found that graphene might be the ideal material for manufacturing plasmonic devices capable of detecting explosive materials, toxic chemicals, and other organic compounds based on the analysis of a single molecule.
“The graphene spaser could be used to design compact spectral measurement devices capable of detecting even a single molecule of a substance, which is essential for many potential applications. Such sensors could detect organic molecules based on their characteristic vibrational transitions (‘fingerprints’), as the light emitted/absorbed falls into the medium infrared region, which is exactly where the graphene-based spaser operates,” said Alexander Dorofeenko, one of the study’s authors.
Eric C. Nallon and others report that graphene chemical vapor sensors with an unmodified surface possess an intrinsic, broad selective nature capable of discriminating between both chemically diverse and chemically similar compounds. The sensors also exhibit other desirable characteristics such as room temperature operation, rapid response and recovery, reversibility, reproducibility, stable operation, low cost, and low power consumption.
Graphene-based nanoelectronic devices have also been researched for use in DNA sensors (for detecting nucleobases and nucleotides), Gas sensors (for detection of different gases), PH sensors, environmental contamination sensors, strain and pressure sensors, and more.
Graphene is much stronger whilst much lighter than carbon fibre hence it can be utilized (probably integrated into plastics such as epoxy) to create a material that can replace steel in the structure of aircraft, improving fuel efficiency, range and reducing weight. It shall also offer multi functionality – strength and good conductivity in polymer composites for aerospace applications.
Ray Gibbs, Chief Executive Officer of Haydale Ltd. sees quite a big opportunity in the interior structures of the aircraft that don’t need as much rigor on evaluations compared to structural components used in the aircraft body itself or, indeed, the engines. “For example, trays, overhead storage lockers, toilet fixtures etc. could all be made from graphene composite materials and reducing weight which is the constant goal of the aircraft industry, without compromising safety,” he says.
Graphene is also a perfect material for aviation electronics, where graphene’s flexibility can contribute to the creation of flexible and lightweight electronic displays and in-flight entertainment suites. Graphene based electrically conductively resins have potential to replace the Copper mesh is currently used in the body of the aircraft to protect it from number of potential lightning strikes during operation. Graphene infused conductive coatings can also de-ice an aircraft quickly and cheaply. Currently, the task of de-icing an aircraft is expensive, difficult and takes a long time, where a team of airport staff have to spray the wings of the plane with a hot liquid, either propylene glycol or ethylene glycol to melt the ice.
We have a project with Airbus to study if we can make parts using graphene for reducing weight and improve resistance. “Graphene is self-diagnosing, just by measuring the electrical resistivity it can conclude that a crack is developing somewhere. Many call it a miracle material but it is not and we call it as a very versatile material and supply is no issue as the world has enough carbon,” he said.
Graphene for Defense Applications
The US Navy has awarded $800,000 to the University of Buffalo to investigate whether graphene could replace existing copper-based power networks on ships. Graphene nanoribbons are able to withstand energy loads of approximately 1,000 times greater than copper. The US Navy (USN) is exploring new techniques to exploit graphene to create a universal method for transferring surface properties as easily as applying a Post-it note. If successful, the project would enable the Naval Research Laboratory (NRL) to take difficult surface chemistry problems and solve them once on graphene, Dr Keith Whitener, a research chemist at NRL, told IHS Jane’s on 27 June.
NRL’s Kinetics and Stabilization of Chemical Groups on Graphene effort seeks to remove the redundancy of trying to develop unique surface chemistry from scratch for each desired substrate. The project could lead to speeding up the development of chemical and biological sensors as well as improving biomechanical and bioelectronics interfaces, Whitener said.
The graphene composite could be used to produce very strong and extra light weight bulletproof vests and security coverings for tanks and aircraft. Light weight, wearable electronics made from graphene are becoming more and more common and can help decrease the load burden for the warfighter, potentially providing chemical, biological, radiological and nuclear (CBRN) early warnings and medical monitoring in the field.
The material has been tested to be 200 times the strength of steel, can stop projectiles from piercing it at 3 km/s, and had a stopping power 10 times greater than that of steel. Once layered on top of each other, sheets of graphene and graphene composites, can absorb extremely high amounts of energy only requiring 4 millimeters in thickness of either material to stop an AK-47 assault rifle bullet from piercing through the skin. Currently bulletproof vests are made of Kevlar which has the capability of stopping small caliber handguns and shotguns. However, to stop impact from an assault rifle such as an AK-47, metal or ceramic plates must be used on top of the vests which are impractical due to their rigidness.
A team of Chinese scientists from the Shanghai Institute of Ceramics at the Chinese Academy of Sciences have reportedly created a super graphene composite. The material is composed of graphene tubes that can withstand a force of 40,000 times its own weight without distortion. To put this into perspective this force is similar to being 10.9km below the ocean’s surface in the Mariana Trench. The researcher’s claim that this graphene composite is an improvement over standard graphene. The material can be compressed to 5% its original size over 1000 times and can still revert back to its original form after compression.
SAAB, a global company, is looking at applying Graphene in camouflage materials for signature management – primarily known as detection avoidance. “Graphene, in combination with other natural substances, could be used to actively change the shape and topology of all manner of surfaces, including ships, aircrafts and even military uniforms,” says SAAB.
Brain Computer Interface
Researchers from the University of Wisconsin, with funding from the Defense Advanced Research Projects Agency, DARPA, have created a new type of brain chip made of graphene that could bring futuristic brain implants much closer to reality.
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