Graphene is perhaps the single most exciting material known to man. It is, so to speak, a material full of promise. It is likely to transform the world in which we live and it is likely to make many people very rich. Those who invest in graphene in the earliest phases of the development cycle stand to make the most from this modern wonder; and so, to invest in graphene now has to be an absolute no-brainer.
For those who want more than just an idle speculation written on the back of a napkin I suggest you consider a recent report from IdTechEx, which forecasts that sales of graphene will reach the 100 million dollars mark by 2018; this from a product that has, at the time of writing, hardly reached the High Street.
What are the benefits of investing in graphene?
Such sales forecasts are based on the versatility of the material and the potential for its incorporation into almost anything. It has already been used to make conductive inks, sports equipment and the hulls of boats, but its true potential is inexcusably vast. Expect to see graphene featuring in smart packaging, super capacitors, composites, ITO replacement, sensors, as well as in the energy industry. Graphene is absolutely set to transform our world.
In which graphene companies should you invest?
So, for those people wishing to invest in graphene, where is the best place to turn? Well, a number of companies are very prominently involved in the development of the nano-material and in researching its capabilities. Many of the big technology companies have a vested interest in the material, as few can afford to be left behind, and some lesser known specialists operating within the nanotechnology field, largely start-ups that have grown out of university research units, are also developing a presence. Choosing which to invest in is, however, no easy thing.
To make things slightly easier it is possibly worth deciding upon a sector of the industry and researching the companies that operate within it. Knowing a little about the science can also help to uncover those companies likely to adopt graphene technology in the future. For now, however, it is perhaps enough to think about the production phase of the industry.
When considering production it is worth knowing that graphene is produced by a number of methods, the two most developed being exfoliation and chemical vapour deposition (hereafter referred to as CVD). Each method produces a slightly different form of the material and each form has the potential to be used for different things. Exfoliating graphene, the cheaper of the two production methods, results in small islands of bilayer product that can be incorporated into energy storage devices, composite building materials,etc. Higher grade CVD graphene is much more expensive to produce but has the potential for use as a replacement for indium tin oxide in the manufacture of smart phones and electronic devices. As someone looking to invest in graphene it would be wise to research each production method and explore the opportunities therein.
A good place to begin your research would be Grafoid, GrafTech, CVD Equipment Corporation and Oxford Instruments. These companies all have an involvement in the graphene industry whether it be in the direct production of the material or in the supply of the specialist technology required for its production.
Nokia is one of the leaders in Graphene based research work and we just reported Nokia prototyping optical sensor based on Graphene. Now, think about a totally different use of Graphene and Nokia has just patented a Self-charging Graphene based Photon-Battery. Yes, you heard it right, self-recharging battery resulting in an energy-autonomous device. Continue reading
In 2012, researchers from the University of Florida reported a record efficiency of 8.6 percent for a prototype solar cell consisting of a wafer of silicon coated with a layer of graphene doped with trifluoromethanesulfonyl-amide (TFSA). Now another team is claiming a new record efficiency of 15.6 percent for a graphene-based solar cell by ditching the silicon all together. Continue reading
Workers stand near pressure vessels at Britain’s first-ever mainland desalination plant, known as the Thames Gateway Water Treatment.
The latest technology for removing salt from seawater, developed by Lockheed Martin, will be a game-changer for the industry, according to Ray O. Johnson, senior vice president and chief technology officer of the jet and weapons manufacturer.
Desalination technology is used in regions of the world, particularly developing countries, where fresh water is not available. Water from oceans or rivers is diverted into treatment plants where the salt is removed and clean drinking water is produced through a process called reverse osmosis.
Imagine a tank with seawater on one side and pure water on the other, separated by a filter with billions of tiny holes. Lots of pressure on the salty side pushes water through faster than the salt, so fresh water comes out the other end.
The problem is that current filters use plastic polymers that use an immense amount of energy (800 to 1,000 pounds per square inch of pressure) to push water through.
Lockheed has developed a special material that doesn’t need as much energy to drag water through the filter.
Graphene is a substance made of pure carbon. Carbon atoms are arranged in a regular hexagonal or honeycomb pattern in a one-atom thick sheet.
This special material is a film of a special structure of carbon, a honeycomb lattice called graphene.
“Graphene is pure carbon that is made in a hot oven on top of a copper sheet
in a vacuum,” John Stetson, the chief technologist at Lockheed for this initiative explained to Business Insider. “Methane gas is put into the vacuum and the methane changes
into a single film of carbon atoms all linked together tightly like chickenwire (at the atomic level) 1,000 times stronger than steel and tolerant of temperature, pressure and pH.”
The sheet is dotted with holes that are one nanometer or less. These holes between carbon atoms trap the salt and other impurities.
Graphene researchers won the Nobel Prize in Physics in 2010 for developing the wonder-material.
In addition, the film is super thin — just a single atom thick — so that the water simply “pops through the very, very small holes that we make in the graphene and leaves the salt behind,” said Stetson.
Lockheed anticipates that their filters will be able to provide clean drinking water “at a fraction of the cost of industry-standard reverse osmosis systems,” their press release says. Water-poor regions of the world will be the first to benefit.
The perforated graphene is aptly called Perforene. Lockheed has the U.S. Patent on this technology and is currently pumping out “pretty big quantities of it” at Lockheed’s advanced technology center in Palo Alto, California, according to Stetson.
The Perforene has a smoky grey-color film that is translucent, even though its carbon, because it is so thin. It’s also about 1,000 times stronger than steel, but still has a permeability that is about 100 times greater than the best competitive membrane out in the market, said Stetson.
Perforene isn’t a game-changer, yet. Lockheed is still in the prototype stage. One challenge is figuring out how to scale up production. Graphene is cheap but it’s very delicate because of its thinness, also making it difficult to transfer.
Stetson says Lockheed is targeting to have a prototype to test in a reverse osmosis plant by 2014 or 2015, where they would simply be able to “plug in” the Perforene to replace the existing filter.
The great news is that this technology is not just limited to desalination plants. It can potentially be used for pharmaceutical filtration, dialysis, and gas separation, to a name a few other uses.
The possibilities are endless.
Bioengineering will certainly be a field in which graphene will become a vital part of in the future; though some obstacles need to be overcome before it can be used. Current estimations suggest that it will not be until 2030 when we will begin to see graphene widely used in biological applications as we still need to understand its biocompatibility (and it must undergo numerous safety, clinical and regulatory trials which, simply put, will take a very long time). However, the properties that it displays suggest that it could revolutionise this area in a number of ways. With graphene offering a large surface area, high electrical conductivity, thinness and strength, it would make a good candidate for the development of fast and efficient bioelectric sensory devices, with the ability to monitor such things as glucose levels, haemoglobin levels, cholesterol and even DNA sequencing. Eventually we may even see engineered ‘toxic’ graphene that is able to be used as an antibiotic or even anticancer treatment. Also, due to its molecular make-up and potential biocompatibility, it could be utilised in the process of tissue regeneration.
One particular area in which we will soon begin to see graphene used on a commercial scale is that in optoelectronics; specifically touchscreens, liquid crystal displays (LCD) and organic light emitting diodes (OLEDs). For a material to be able to be used in optoelectronic applications, it must be able to transmit more than 90% of light and also offer electrical conductive properties exceeding 1 x 106 Ω1m1 and therefore low electrical resistance. Graphene is an almost completely transparent material and is able to optically transmit up to 97.7% of light. It is also highly conductive, as we have previously mentioned and so it would work very well in optoelectronic applications such as LCD touchscreens for smartphones, tablet and desktop computers and televisions.
Currently the most widely used material is indium tin oxide (ITO), and the development of manufacture of ITO over the last few decades time has resulted in a material that is able to perform very well in this application. However, recent tests have shown that graphene is potentially able to match the properties of ITO, even in current (relatively under-developed) states. Also, it has recently been shown that the optical absorption of graphene can be changed by adjusting the Fermi level. While this does not sound like much of an improvement over ITO, graphene displays additional properties which can enable very clever technology to be developed in optoelectronics by replacing the ITO with graphene. The fact that high quality graphene has a very high tensile strength, and is flexible (with a bending radius of less than the required 5-10mm for rollable e-paper), makes it almost inevitable that it will soon become utilized in these aforementioned applications.
In terms of potential real-world electronic applications we can eventually expect to see such devices as graphene based e-paper with the ability to display interactive and updatable information and flexible electronic devices including portable computers and televisions.
Another standout property of graphene is that while it allows water to pass through it, it is almost completely impervious to liquids and gases (even relatively small helium molecules). This means that graphene could be used as an ultrafiltration medium to act as a barrier between two substances. The benefit of using graphene is that it is only 1 single atom thick and can also be developed as a barrier that electronically measures strain and pressures between the 2 substances (amongst many other variables). A team of researchers at Columbia University have managed to create monolayer graphene filters with pore sizes as small as 5nm (currently, advanced nanoporous membranes have pore sizes of 30-40nm). While these pore sizes are extremely small, as graphene is so thin, pressure during ultrafiltration is reduced. Co-currently, graphene is much stronger and less brittle than aluminium oxide (currently used in sub-100nm filtration applications). What does this mean? Well, it could mean that graphene is developed to be used in water filtration systems, desalination systems and efficient and economically more viable biofuel creation.
Graphene is strong, stiff and very light. Currently, aerospace engineers are incorporating carbon fibre into the production of aircraft as it is also very strong and light. However, graphene is much stronger whilst being also much lighter. Ultimately it is expected that graphene is 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. Due to its electrical conductivity, it could even be used to coat aircraft surface material to prevent electrical damage resulting from lightning strikes. In this example, the same graphene coating could also be used to measure strain rate, notifying the pilot of any changes in the stress levels that the aircraft wings are under. These characteristics can also help in the development of high strength requirement applications such as body armour for military personnel and vehicles.
Offering very low levels of light absorption (at around 2.7% of white light) whilst also offering high electron mobility means that graphene can be used as an alternative to silicon or ITO in the manufacture of photovoltaic cells. Silicon is currently widely used in the production of photovoltaic cells, but while silicon cells are very expensive to produce, graphene based cells are potentially much less so. When materials such as silicon turn light into electricity it produces a photon for every electron produced, meaning that a lot of potential energy is lost as heat. Recently published research has proved that when graphene absorbs a photon, it actually generates multiple electrons. Also, while silicon is able to generate electricity from certain wavelength bands of light, graphene is able to work on all wavelengths, meaning that graphene has the potential to be as efficient as, if not more efficient than silicon, ITO or (also widely used) gallium arsenide. Being flexible and thin means that graphene based photovoltaic cells could be used in clothing; to help recharge your mobile phone, or even used as retro-fitted photovoltaic window screens or curtains to help power your home.
One area of research that is being very highly studied is energy storage. While all areas of electronics have been advancing over a very fast rate over the last few decades (in reference to Moore’s law which states that the number of transistors used in electronic circuitry will double every 2 years), the problem has always been storing the energy in batteries and capacitors when it is not being used. These energy storage solutions have been developing at a much slower rate. The problem is this: a battery can potentially hold a lot of energy, but it can take a long time to charge, a capacitor, on the other hand, can be charged very quickly, but can’t hold that much energy (comparatively speaking). The solution is to develop energy storage components such as either a supercapacitor or a battery that is able to provide both of these positive characteristics without compromise.
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. Also, graphene is being studied and developed to be used in the manufacture of supercapacitors which are able to be charged very quickly, yet also be able to store a large amount of electricity. Graphene based micro-supercapacitors will likely be developed for use in low energy applications such as smart phones and portable computing devices and could potentially be commercially available within the next 5-10 years. Graphene-enhanced lithium ion batteries could be used in much higher energy usage applications such as electrically powered vehicles, or they can be used as lithium ion batteries are now, in smartphones, laptops and tablet PCs but at significantly lower levels of size and weight.
Today’s graphene is normally produced using mechanical or thermal exfoliation, chemical vapour deposition (CVD), and epitaxial growth. One of the most effective way of synthesised graphene on a large scale could be by the chemical reduction of graphene oxide.
Since the first report on mechanical exfoliation of monolayer graphene in 2004, interest in graphite oxide (which is produced by oxidation of graphite) has increased dramatically as people search for a cheaper, simpler, more efficient and better yielding method of producing graphene, that can be scaled up massively compared to current methods, and be financially suitable for industrial or commercial applications.
While graphite is a 3 dimensional carbon based material made up of millions of layers of graphene, graphite oxide is a little different. By the oxidation of graphite using strong oxidizing agents, oxygenated functionalities are introduced in the graphite structure which not only expand the layer separation, but also makes the material hydrophilic (meaning that they can be dispersed in water). This property enables the graphite oxide to be exfoliated in water using sonication, ultimately producing single or few layer graphene, known as graphene oxide (GO). The main difference between graphite oxide and graphene oxide is, thus, the number of layers. While graphite oxide is a multilayer system in a graphene oxide dispersion a few layers flakes and monolayer flakes can be found.
Properties of Graphene Oxide
One of the advantages of the gaphene oxide is its easy dispersability in water and other organic solvents, as well as in different matrixes, due to the presence of the oxygen functionalities. This remains as a very important property when mixing the material with ceramic or polymer matrixes when trying to improve their electrical and mechanical properties.
On the other hand, in terms of electrical conductivity, graphene oxide is often described as an electrical insulator, due to the disruption of its sp2 bonding networks. In order to recover the honeycomb hexagonal lattice, and with it the electrical conductivity, the reduction of the graphene oxide has to be achieved. It has to be taken into account that once most of the oxygen groups are removed, the reduced graphene oxide obtained is more difficult to disperse due to its tendency to create aggregates.
Functionalization of graphene oxide can fundamentally change graphene oxide’s properties. The resulting chemically modified graphenes could then potentially become much more adaptable for a lot of applications. There are many ways in which graphene oxide can be functionalized, depending on the desired application. For optoelectronics, biodevices or as a drug-delivery material, for example, it is possible to substitute amines for the organic covalent functionalization of graphene to increase the dispersability of chemically modified graphenes in organic solvents. It has also been proved that porphyrin-functionalized primary amines and fullerene-functionalized secondary amines could be attached to graphene oxide platelets, ultimately increasing nonlinear optical performance.
In order for graphene oxide to be usable as an intermediary in the creation of monolayer or few-layer graphene sheets, it is important to develop an oxidization and reduction process that is able to separate individual carbon layers and then isolate them without modifying their structure. So far, while the chemical reduction of graphene oxide is currently seen as the most suitable method of mass production of graphene, it has been difficult for scientists to complete the task of producing graphene sheets of the same quality as mechanical exfoliation, for example, but on a much larger scale. Once this issue is overcome, we can expect to see graphene become much more widely used in commercial and industrial applications.
In simple terms, graphene, is a thin layer of pure carbon; it is a single, tightly packed layer of carbon atoms that are bonded together in a hexagonal honeycomb lattice.
In more complex terms, it is an allotrope of carbon in the structure of a plane of sp2 bonded atoms with a molecule bond length of 0.142 nanometres. Layers of graphene stacked on top of each other form graphite, with an interplanar spacing of 0.335 nanometres.
It is the thinnest compound known to man at one atom thick, the lightest material known (with 1 square meter coming in at around 0.77 milligrams), the strongest compound discovered (between 100-300 times stronger than steel and with a tensile stiffness of 150,000,000 psi), the best conductor of heat at room temperature (at (4.84±0.44) × 10^3 to (5.30±0.48) × 10^3 W·m−1·K−1) and also the best conductor of electricity known (studies have shown electron mobility at values of more than 15,000 cm2·V−1·s−1). Other notable properties of graphene are its unique levels of light absorption at πα ≈ 2.3% of white light, and its potential suitability for use in spin transport.
Bearing this in mind, you might be surprised to know that carbon is the second most abundant mass within the human body and the fourth most abundant element in the universe (by mass), after hydrogen, helium and oxygen. This makes carbon the chemical basis for all known life on earth, so therefore graphene could well be an ecologically friendly, sustainable solution for an almost limitless number of applications. Since the discovery (or more accurately, the mechanical obtainment) of graphene, advancements within different scientific disciplines have exploded, with huge gains being made particularly in electronics and biotechnology already.
Graphene – which has a similar molecular structure to the graphite commonly found in pencils – was discovered in 2004. The material is two-dimensional, one atom thick, has superconducting properties, and is 200 times stronger than steel.
Bold claims for new battery technology have been around since the invention of the lead-acid battery more than 150 years ago.
But researchers at Manchester University in the UK say their latest discovery involving the new wonder material graphene could be the most revolutionary advance in battery technology yet.
According to a study published in the journal Nature, graphene membranes could be used to sieve hydrogen gas from the atmosphere — a development that could pave the way for electric generators powered by air.
“It looks extremely simple and equally promising,” said Dr Sheng Hu, a post-doctoral researcher in the project. “Because graphene can be produced these days in square metre sheets, we hope that it will find its way to commercial fuel cells sooner rather than later.”
At the heart of the technology is the remarkable physical properties of graphene — a substance with the same atomic structure as the lead found in the humble household pencil.
Isolated in 2004 by a team from Manchester University headed by Andrew Geim and Kostya Novoselov — both of whom won the Nobel Prize for Physics for their discovery in 2010 — graphene is already well known as a technological game-changer.
The first two-dimensional crystal known to science, graphene is the thinnest, lightest and strongest object ever obtained. It is harder than diamond and 200 times stronger than steel.
Flexible, transparent and able to conduct electricity even better than copper, the ground-breaking substance is set to revolutionize everything from smartphones and wearable technology to green technology and medicine.
Renowned for its barrier qualities, graphene is just one atom thick – more than a million times thinner than a human hair.
The latest discovery makes graphene attractive for possible uses in proton-conducting membranes which are at the core of modern fuel-cell technology.
Fuel cells work by using oxygen and hydrogen as a fuel, converting the chemical energy produced by its input directly into electricity. However, current membranes that separate the protons necessary for this process are relatively inefficient, allowing contamination in the fuel crossover.
Using graphene membranes could boost their efficiency and durability.
The team found the protons passed through the ultra-thin crystals with relative ease, especially at raised temperatures and with the use of a platinum-based catalyst coated on the membrane film.