APPLICATIONS FUTURE MARKETS FLEXIBLE DISPLAYS, OPTICAL SWITCHES, CONDUC- TIVE INKS, TRANSISTORS, INTEGRATED CIRCUITS & MEMORY DEVICES COMPANIES

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1 350GRAPHENE EDITION 1 FUTURE MARKETS March FLEXIBLE DISPLAYS, OPTICAL SWITCHES, CONDUC- TIVE INKS, TRANSISTORS, INTEGRATED CIRCUITS & MEMORY DEVICES APPLICATIONS ITO replacement, conductive coatings and many more. COMPANIES All the leading companies profiled. MARKETS End user markets and products. RESEARCH Main research centres profiled.

2 contents GRAPHENE IN ELECTRONICS EDITOR S LETTER EXECUTIVE SUMMARY Graphene has moved swiftly from the laboratory to the marketplace. INTRODUCTION Graphene types, properties and history. Production methods Main production methods for graphene. Production volumes Graphene production in tons projected, prices and capacities. COMPETING AGAINST NANOTUBES Many of the current and potential applications of carbon nanotubes may be taken by graphene. GRAPHENE PRODUCT INTEGRATION The adaptability of graphene to process and product integration. GRAPHENE IN THE ELECTRONICS SECTOR Graphene in the energy sector- Technology roadmaps, applications, recent research and product development, target market revenues and companies. Areas covered include Transparent Conductors, Optical Switches, Transistors and Integrated Circuits, Memory Devices and Spintronics. 34 COMPANIES Producers, application developers and OEMs Graphene in electronics GRAPHENE IN ELECTRONICS JAN

3 EXECUTIVE SUMMARY EXECUTIVE SUMMARY Graphene has moved swiftly from the research laboratory to the marketplace. Driven by demand from markets where advanced materials are required, graphene promises to outstrip all current nanomaterials, especially in electronics applications. Revenues for smartphones and tablets now outstrip the entire consumer electronics (CE) market, with a market of over $325 billion in Graphene will drive the next generation of transparent conductive films for displays. Other markets graphene is impacting include aerospace, automotive, coatings and paints, communications, sensors, solar, oil, and lubricants. The exceptional electron and thermal transport, mechanical properties, chemical stability of graphene and combinations thereof make it a potentially disruptive technology for electronics applications. Application areas at different stages of commercial development include: Transparent Conductors Optical Switches Transistors and Integrated Circuit Memory Devices Spintronics. Applications are coming onto the market for polymer composites and EMI shielding coatings. Graphenebased conducting inks are also finding their way into smart cards and radio-frequency identification tags. China is expecting to bring graphene products to the market in 2014 in consumer electronics. Companies such as IBM, LG Electronics and Samsung are pursuing applications for graphene in electronics and optics. Many of the current and potential applications of carbon nanotubes may be taken by graphene, as it displays enhanced properties but with greater ease of production and handling. In this regard, carbon nanotubes may be viewed as a stalking horse for commercial applications of graphene. Most graphene producers currently produce graphene nanoplatelets and graphene oxide. Within the last year couple of years graphene producers such as XG Sciences, Angstron Materials and Vorbeck Materials have increased production capabilities considerably. Producers are generally small, start-up companies who have witnessed an explosion in demand for their materials from a variety of industries. The majority of near-term demand is for composites and coatings for application in the automotive, plastics, coatings, construction, metals, batteries, aerospace and energy markets. 3

4 Graphene as a new material still faces many challenges ranging from synthesis and characterization to the final device fabrication. Barriers to widespread industry uptake mirror carbon nanotubes in many respects: functionalization and dispersion; mass manufacturing at an acceptable cost (a major issue); need for application partnerships; and health and safety issues. The severe chemical conditions required to prepare graphene from naturally occurring graphite has become the biggest limiting factor for high scale graphene production and commercialization. The preparation and transfer of high quality graphene is still not viable in a cost effective manner. Salient points about the current graphene market are: Currently there is an oversupply situation in the graphene market especially for low quality graphene. Demand for graphene is still relatively small. Most sales of graphene are nanoplatelets/powders for conductive inks and polymers. CVD graphene films are primarily used in R&D. Cost remains a significant barrier to widespread industry uptake. The current market is estimated to be between US$13-$15 million. However this will grow significantly in the next 10 years and is likely to be larger than projected figures from a number of market consutancies. XG Sciences have over 600 customers - in the automotive, electronics, battery and aerospace industries. The most active companies are Asian electronics and battery makers. The company says they generated $4 million in revenue in In the next 2-3 years there is likely to be graphene enabled-applications in ultra thin flexible Li ion batteries, large supercapacitors, water membranes, biosensors, optical sensors, solar cells and conductive composites. The projected killer app for graphene is definitely transparent conductive films for displays, but that is not proven yet. Enhancement of conductive inks and composites appear to be shorter-term opportunities. Graphene s marketability is based on the scale of the end user markets it is most likely to impact. For example, the global market for polycrystalline silicon (polysilicon) market is approximately 250, 000 tons, with prices between $15-$20 a kg. This is a $4billion plus market and graphene is expected to penetrate a significant percentage of it by The global Li-Ion Battery market is valued at around $9.3 billion and graphene is under widespread development as a replacement anode material. Most large companies have a wait and see strategy as the commercial value has yet to be quantified and most research is at the fundamental stage. Korean and US companies lead the way in patenting graphene. China is also increasingly active but the vast majority of patenting is by research institutions rather than companies. Most product development in China is for supercapactitor and battery electrodes. Most patenting by industry is by companies in the electronics sector in Asia and the US. Competition from silicon in semiconductors and sensors as well as carbon fiber (composites) is significant. Other competing technologies include sliver nanowires and carbon nanotubes as well as other 2D materials such as boron nitride, molybdenum disulfide, tungsten tungsten disulfide and germanane. Due to graphene s comparable or better properties and lower production cost, carbon nanotubes will be replaced in applications which do not significantly benefit from nanotubes 1-D nature. It remains to be seen how graphene powders will compete with incumbent carbon blacks in rubbers and other composites, and where the markets place the tradeoffs between price and performance. Yet there can be no question that graphene materials will creep into the carbon black markets, especially for higher performance materials. Graphene s incorporation into the marketplace is just beginning, and all signs point to strong growth ahead. 4

5 METHODOLOGY Report methodology The report covers the main graphene suppliers and application developers and their production methods. The market is also forecasted from 2010 through to 2020, in terms of production volumes. End user markets and applications are also outlined and forecast. The research methodology initially encompassed a comprehensive and exhaustive search of the literature on graphene. Secondary sources included journals and related books, trade literature, marketing literature, technology roadmaps, other product/promotional literature, annual reports, analyst reports, conference proceedings and other publications. An extensive patent analysis was conducted to gauge technological innovation and to determine research activity as it applies to new product development. A series of interviews were conducted via and phone with nanotechnology and nanomaterials company representatives, academics, technology suppliers, technical experts, trade association officials, and consulting companies. In addition, most of the service providers and end users were contacted to evaluate current and future demands. The market was then quantified relevant application impact and the main prerequisites for commercial success were identified including performance of the technology, supplier distribution, legislation, pricing of competing products, sale of complementary products, industry environment and demographics of the customer. Various methodologies and data sources were used to develop the projections, including trend-line projections, Delphi technique, technology adoption life-cycling modelling, inputoutput analysis, and estimates of future demand from industry sources. 5

6 INTRODUCTION Introduction 6 Graphene is a flat one-atom thick sheet of sp2 carbon atoms densely packed in a honeycomb crystal lattice structure. It is the basic structural element for graphite, carbon nanotubes, and fullerenes. Graphene possesses a range of unique properties - an exciting electronic character, described as a zerogap semiconductor, unparalleled strength (breaking strength ~40 N/m, Young s modulus~1.0 TPa), and record thermal conductivity. Charge carriers, described as massless Dirac fermions, exhibit ballistic movement across submicron distances approaching relativistic speeds, with intrinsic carrier mobilities up to 200,000 cm 2 V 1 s 1. Graphene can maintain current densities six orders of magnitude greater than that of copper. All of this can be achieved with little electronic noise (exhibiting little extraneous noise from outside sources), which is increasingly important as microelectronic devices continue to shrink in size. With thickness on the order of atoms, graphene has a high surface area-to-volume ratio while maintaining incredible flexibility. As additional layers are introduced, the structure becomes increasingly complex, resulting in more distinct and/or unique behavior. Depending on the number of layers, the magnitude of the electric field applied, and the edge orientation, the band gap of the material can be engineered to achieve a wide range of values. In 2004, Geim with his colleagues succeeded in isolating graphene flakes by a very simple method of repeated peeling-off, by scotch tape, of Highly Oriented Pyrolytic Graphite (HOPG). The report by Geim and those following demonstrated that graphene exhibits tremendous electronic, electric, mechanical and chemical properties. However, there has been some contention over the importance of these specific findings. The International Union of Pure and Applied Chemistry (IUPAC) define graphene as a single layer of carbon atoms. However the research literature covers bilayer, trilayer and multilayer graphene. Industry generally

7 includes any highly exfoliated graphite product under the graphene umbrella. Vorbeck Materials, for example, predominantly produces single-layer graphene and a significant amount of Angstron s production is devoted to this type. However, Angstron also produces 30-layer graphene in significant quantities and XG Sciences nanoplatelets are typically 5 nanometers thick, corresponding to more than 16 layers of graphene. Because of its high electronic mobility, structural flexibility, and capability of being tuned from p-type to n-type doping by the application of a gate voltage, graphene is considered a potential breakthrough in terms of carbon-based nanoelectronics. Research into applications for carbon graphene nanosheets has focused on uses as platforms for next-. wave microchips, active materials in field emitter arrays for flat panel screen displays, in biological sensors and medical imaging devices, in solar energy cells, and in high-surface area electrodes for use in bio-science Graphene is a possible replacement material where carbon nanotubes are presently used. Though graphene and carbon nanotubes are nearly identical in their chemical makeup and mechanical properties, graphene is better than carbon nanotubes at lending its attributes to a material with which it s mixed. Advantages over carbon nanotubes include: Rough and wrinkled surface texture of graphene, caused by a very high density of surface defects: These defects are a result of thermal exfoliation processes used to manufacture bulk quantities of graphene from Table 1: Engineered graphene properties (Source: Graphene Frontiers, Ruoff etc.) Engineered Properties Applications High room temperature mobility (~200,000 cm2v-1s-1) and high electrical conductivity (ballistic electron transfer; high mobility) High strength (~1100 GPa modulus, fracture strength ~130 GPa) High curability for current density (Low density ~2 g/cm3) High surface/weight ratio (specific surface area (limit: 2630 m2/g) High light transparency High sensitivity for chemicals (Physical properties can be chemically tuned ) High thermal conductivity (Thermal conductivity ~3000 W/m-K in plane and highly anisotropic; ~ 2 W/m-K out of plane) High barrier material (impermeable if defect-free) Applications in high speed transistors, spin devices, single electron transistors, semiconductor memory, QHRS (Quantum Hole Resistance Standard), RF, MEMS, silicon replacement Composite materials Incredible rigidity lends themselves to nanoscale pressure sensors Wiring materials Energy storage (fuel cells) Transparent electrodes and laser materials Chemical and bio sensors. Hydrogen storage materials Heat / energy storage, thermal management Coatings 7

8 graphite. These wrinkly surfaces interlock extremely well with the surrounding polymer material, helping to boost the interfacial load transfer between graphene and the host material. Surface area: As a planer sheet, graphene benefits from considerably more contact with the polymer material than the tube-shaped carbon nanotubes. This is because the polymer chains are unable to enter the interior of the nanotubes, but both the top and bottom surfaces of the graphene sheet can be in close contact with the polymer matrix. Geometry: when microcracks in the composite structure encounter a two-dimensional graphene sheet, they are deflected, or forced to tilt and twist around the sheet. This process helps to absorb the energy that is responsible for propagating the crack. Crack deflection processes are far more effective for two-dimensional sheets with a high aspect ratio such as graphene, as compared to one-dimensional nanotubes. Graphene shows good near-term potential in composites. The incorporation of graphene into a composite is relatively simple and there are numerous near-term applications of this technology, including sorbent/ filter/medical applications, lightweight high-strength structural components, electrically and/or thermally conducting nanocomposites. Composite-quality graphene has the potential to be a lot cheaper than nanotubes, although costs are currently similar. Graphene also has the advantage of greater ease of dispersion in resins than nanotubes. Table 2: Comparative properties of graphene with nanoclays and carbon nanotubes Physical Structure Properties Exfoliated Clay Carbon Nanotubes Platelet ~1nm x 100 nm Cylinder ~1nm x 100 nm Graphite Nanoplatelets Platelet ~1nm x 100 nm Chemical Structure SiO2, Al2O3, MgO, K2O, Fe2O3 Graphene Graphene Tensile strength ~ 1 GPa ~ 180 GPa ~10 20 GPa Electrical Resistivity Ohm cm ~50x10-6 Ohm cm 50x10-6 Ohm cm Thermal conductivity 6.7x10-1 W/mK 3000 W/m K 3000 W/m K CTE 8 16x10-6 1x10-6 1x10-6 Density, g/cm ~2.0 8

9 PRODUCTION Production Methods Graphene can be manufactured in 2 formats: films format and powder format. For films format the volume scale is an area measure (like cm2, m2, sq. inch, etc.). For the powder format the volume scale is (kg, Tons, etc.). Graphene can be produced by several techniques: exfoliation from bulk graphite chemical reduction of exfoliated graphite oxide precipitation from bulk metals growth on SiC by silicon desorption chemical vapor deposition on copper surface10 or metal surfaces with extremely C solubility of C diffusivity. Perfect graphene does not exist naturally, but bulk and solution-processable functionalized graphene materials can now be prepared. There are several techniques for graphene synthesis. Each method has its own benefits and related drawbacks. Another trend is whether one wishes to synthesize defect free graphenes (purity) or graphenes with defects (containing oxygen species onto the surface). The drawback of graphene materials with defects is the loss of some of the interesting properties of graphene. On the other hand, defects could provide numerous application opportunities. Therefore, not only the quantity of graphene but the types of applications dictate graphene s preparative methods. Well practiced methods of making graphene today are mechanical exfoliation, chemical exfoliation, solvo-thermal reduction, and chemical vapour deposition (CVD) or a combination of these. The main drive in graphene synthesis is the production of graphene in bulk quantities. In 2010, researchers at Sungkyunkwan University in Suwon, South Korea, reported using carbon-rich vapour to deposit graphene films measuring 75 centimeters diagonally on copper plates, which are then etched away and recycled. Samsung is already testing this technique for use in commercial touch screens. The highest-quality sheets are currently made by heating a wafer of silicon carbide in a vacuum, leaving a layer of pure graphene on the top surface. This method has fewer problems with uncontrollable variety from batch to batch than does nanotube synthesis, and the flat sheets that result are bigger and easier to handle than nanotubes. Industrial fabrication of graphene requires low to moderate cost, high yields (or scalability), and control over quality. Three main techniques have emerged for the production of graphene. These include bottom-up approaches (deposition) and top-down approaches (carbonization/decomposition, exfoliation). Graphene films have higher quality, homogeneity and the production process is cheaper than the chemical exfoliation method and is industrial-scalable. The high-value applications for graphene generally require graphene films (solar cells, electronics, transparent electrodes, ultracapacitors, etc.). Table 3: Main production methods for graphene Process Comments Applications Bottom-Up Graphene Top-Down Graphene In top-down processes, graphene or modified graphene sheets are produced by separation/ exfoliation of graphite or graphite derivatives (such as graphite oxide (GO) and graphite fluoride). In top-down processes, graphene or modified graphene sheets are produced by separation/ exfoliation of graphite or graphite derivatives (such as graphite oxide (GO) and graphite fluoride). Displays (transparent electrodes, touchscreens) Electronics (transistors, frequency multipliers) Gas sensors Automotive and aerospace (conductive coatings, structural composites) Printable electronics (conductive inks) Energy (high surface electrodes) 9

10 Among the several synthesis methodologies for graphene, chemical vapor deposition (CVD) allows the production of large area graphene as required for its application as transparent conductive layer substituting ITO. Recently, many attempts to produce graphene sheets in large quantities via chemical reduction of exfoliated graphite oxide (GO) have been reported. During the oxidation process of graphite, the unique electronic properties of graphene dramatically degrade. The electrical conductivity of the graphene oxide sheets can be partially restored by the reduction step; however, this results in their irreversible agglomeration. Therefore, different strategies to disperse graphene sheets before or during reduction step have been used, including stabilization by various polymeric dispersants or surfactants and covalent/ non-covalent functionalization. Graphene mass production has recently become a crucial issue. Among the different synthesis routes available, chemical exfoliation of graphene oxide (GO) and thermal exfoliation of graphite intercalation compounds (GIC) seem to be the most promising candidates for large yield production. Table 4: Graphene production overview (Ruoff) Method Micro-mech anical exfoliation of graphite Reduction of graphene oxide Quality Good Not pristine graphene Growth on metal substrates Desorption of Si from SiC Size 10~100 µm nm to µm SiC wafer size Transfer Yes Yes Yes (Ni and Cu) Direct exfoliation of graphite CVD or PECVD of graphene powder Good Good Good Good nm to µm ~ nm No Yes Yes Scalable No Yes Yes Yes Yes Table 5: Graphene production methods Chemical Vapor Deposition (CVD) Exfoliation method Graphene produced with the CVD process has demonstrated large area, high quality, controllable number of layers and low defects. CVD approach has been found to be by far the most effective technique to produce high quality, large scale graphene that can be compatibly integrated into electronics. This is the best graphene quality format for high requirements applications (electronics, optoelectronics, solar cells, biomedical devices, energy storage, etc.). However, this is a relatively expensive production technique. Also, in such a method, since a composite material, in which a graphene film is strongly bonded to a metal foil due to a catalytic action of the metal foil, is produced, in order to transfer the film once formed on the metal foil to a substrate, all metal foil need to be removed using an acid, which makes a production process complicated and results in a problem such as a fear of causing a defect on the film in a transferring process. Currently, the most promising methods for large scale production of graphene are based on the exfoliation and reduction of GO. Chemical exfoliation involves inserting ( intercalating ) molecules into bulk graphite in order to separate the crystalline planes into individual graphene layers. Graphene extracted by microexfoliation shows very good electrical and structural quality. However, the shortcoming of this most elementary method is its nonscalability and production of uneven graphene films with small area. Since a reducing process is necessary and it is difficult to complete the reduction, there is a problem such that it is difficult to secure enough electric conductivity and transparency. 10

11 PRODUCTION Epitaxial growth Wet-chemistry approach Micromechanical Cleavage Plasma Graphene is also synthesizable by annealing of SiC crystal at a very elevated temperature (~2000 K) in ultra-high vacuum. Thermal desorption of Si from the top layers of SiC crystalline wafer yields a multilayered graphene structure that behaves like graphene. The number of layers can be controlled by limiting time or temperature of the heating treatment. The quality and the number of layers in the samples depend on the SiC face used for their growth. Although the produced structure has a larger area than that obtainable by the exfoliation technique, still the coverage or area is way below the size required in electronic applications. Moreover, it is difficult to functionalize graphene obtained by this route. Wet-chemistry based approach is also employed to synthesize graphene by reduction of chemically synthesized graphene oxide. Graphite is transformed into acid-intercalated graphite oxide by a severe oxidative treatment in sulphuric and nitric acid. The intercalant is then rapidly evaporated at elevated temperatures, followed by its exposure to ultrasound or ball milling. Exfoliation of the graphite oxide readily occurs in aqueous medium due to the hydrophilicity of the former. Subsequent reduction of exfoliated graphite oxide sheets by hydrazine results in the precipitation of graphene owing to its hydrophobicity. It is more versatile than the methods comprising exfoliation and epitaxial growth on SiC and easier to scale up. Yet, it has a poor control on the number of layers of graphene produced. Graphene synthesized by this method may remain partially oxidized, which potentially changes its electronic, optical, and mechanical properties. In this method there is a problem such that the SiC substrate to be used is expensive and transferring from the SiC substrate is difficult. Micromechanical cleavage of graphite gave birth to the interest in graphene. Micromechanical cleavage is a technique that peels off individual layers of graphene from bulk graphite. The method involves rubbing a piece of graphite across an adhesive tape or other surface. Though seemingly rudimentary, this technique can achieve single-layer graphene up to 100 um in size and has proved useful for experimental studies. But, the difficulty of locating individual graphene flakes produced by this method poses a problem for large-scale device integration. It can produce large-size, high-quality sheets but in very limited quantities, which makes it only suitable for fundamental studies or electronic applications. The Haydale Split Plasma method has been designed to enable the take up of nano carbons and other nanopowders as functional fillers. The barriers that Haydale has overcome in respect of GNPs are the same as for Carbon Nano Tubes ( CNTs ) where the plasma process performs these fundamental actions: Remove contamination Surface Engineering De-Agglomeration 11

12 PRODUCTION Low-cost, high-yield production of graphene is essential for practical applications as current processes suffer from a range of flaws. Micro-mechanically cleaved graphene is widely used for the fundamental research as due to its quality, it is the closest to the nature of graphene. A variety of additional methods to those listed in the previous table have been developed in the past 12 months in research institutions. Researchers at Tennessee s Oak Ridge National Laboratory developed a new method of creating graphene via chemical vapor deposition at atmospheric pressure, which could allow them to produce greater quantities for production use ( pdf). Researchers from Ulsan National Institute of Science and Technology (UNIST) and Case Western Reserve University achieved high yield of edge-selectively carboxylated graphite (ECG) by a simple ball milling of pristine graphite in the presence of dry ice (solid phase of carbon dioxide). High yield of edge-carboxylated graphite (ECG) was produced and the resultant ECG is highly dispersible in various polar solvents to self-exfoliate into graphene nanosheets useful for solution processing ( full.pdf). Mass production of graphene sheets has yet to be achieved, and they are mainly targetted at research and development. Several companies are offering graphene sheets in low volume including Graphene Industries, Graphene Supermarket, Graphene Square, Graphenea and PlanarTech. Several companies are offering products and materials based on graphene such as graphene ribbons, graphene-oxide, graphene nanoplatelets (GNPs), graphene powders, graphene composites. Producers include Angstron Materials, Vorbeck Materials, XG Sciences and HDPlas. 12

13 GRAPHENE PRODUCTION Graphene Production Volumes Production increasing Graphene production has increased greatly in the last few years. In 2009, the total production output of various types of graphene was approximately 12 tons. Angstron Materials, Vorbeck Materials and XG Sciences use relatively inexpensive, simple and low-energy graphene production techniques. Near-term applications for graphene are mainly in coatings, composites and transparent electrodes and it is to these markets that the majority of graphene is used in at present. Academic and industrial research is also a significant market for graphene. In May 2012, XG Sciences moved into a new production facility which will increase their production capacity from 5 to 80 tons per year, reducing price to $40-$50 per kilogram. Haydale and Graphene Technologies are also scaling up to multi-ton capacities. Ningbo Morsh Technology launched the world s first graphene production line with an annual capacity of 300 tons in Ningbo, Zhejiang Province. Garmor Inc. is planning production of 100 tons per annum. There are a number of multinationals with activities in graphene including Intel and IBM (data storage and computing), Dow Chemicals, Dupont and BASF, and 3M and Samsung (consumer electronics). BASF has formed a partnership with Vorbeck to jointly develop products. Dow is still relatively non-committal despite ongoing research in cableshielding applications. It is widely accepted that the bottleneck in the graphene-based technology is its production on a large-scale. Various approaches have been used to produce graphene or graphene-like materials including one-step graphite exfoliation, chemical vapor deposition (CVD) of methane gas, graphite stamping, graphite oxide reduction and carbon nanotube unzipping. Production techniques Graphene is derived from graphite ore or synthesized. There are a large number of synthesis processes, and these processes begin with an array of material sources such as graphite, carbon nanotube, carbon precursor, CO2. To obtain Graphene from graphite ore, one needs to perform another manufacturing step, for example liquid phase exfoliation or another chemical exfoliation procedure. Exfoliation is a term that describes the breaking of bulk graphite ore into its constituent Graphene layers. In recent years, various manufacturers have used Hummer s technique in which graphite is initially oxidized and converted to Graphene oxide. Graphene oxide is then reduced to Graphene using specific reducing agents. However, the initial oxidation process is highly exothermic resulting into explosion risks and toxic gas release that hinders the scalability of the conversion process. Exfoliation Most recently, novel exfoliation techniques have been developed in which graphite is directly exfoliate into Graphene without intermediate oxidation steps. Currently these Table 6: Graphene demand, , tons, conservative and optimistic estimates Year Conservative estimate Optimistic estimate

14 GRAPHENE PRODUCTION techniques are the lowest cost production methods for Graphene, however optimization is needed to produce larger Graphene sheets. This optimisation is much easier when the input graphite has large flakes and higher purity. Canadian Graphene producers such as NanoXplore and Grafoid are leaders in these novel exfoliation techniques. Graphene can also be obtained as a solution of very small flakes (~100 nm across) produced by ultrasonic exfoliation, which can be obtained from companies such as Nanointegris for approximately $750 per mg. Exfoliated graphene demonstrates the most impressive physical properties, reaching towards theoretically predicted current conduction, mechanical strength, etc. However, the coverage of mechanically exfoliated graphene is only on the order of a few small flakes per square centimeter, which is not sufficient enough for applications. CVD Another Graphene production technique is Chemical Vapour Deposition (CVD). CVD results in large-area Graphene with superb qualities but the production technique is expensive and therefore the technique is most suitable for electronic and photonic applications where Graphene coating (versus Graphene powder) is needed. CVD is a vacuum-based process with various gases used and at multiple stages of production. The resulting safety precautions lead to a capital intensive cost structure that significantly hinders the scalability of this process. Other more conventional techniques, such as Hummers that results into reduced Graphene oxide, are Table 7: Graphene prices and production capacity of main suppliers Company Angstron Materials Current production capacity/year 25 tons plus. Potential plans for tons. Example Prices Graphene Oxide Solution: $175/g Graphene Powder: $120/100g Durham Graphene Science 4-5 tons $500-$4000 per kg Graphene Devices Ltd. 50Kg $250-$5000 per kg Graphenea In the Thin Film format they have a capacity of 10,000 square inches/year. Graphene oxide: 89 EUR (119 USD) for 250mL (water dispersion, 4mg/mL) CVD Graphene films: 10 EUR/cm 2 Graphene Square 500KG CVD Graphene on Ni Wafer (10mm X 10mm, 20 ea): $420 CVD Graphene on Cu Foil (50mm X 50mm, 1ea): $281 Graphene Technologies Current: 50 kg annually. Future: 1 ton annually $500-$1000 per kg Nanointegris 10Kg PureSheets QUATTRO: $199/5mg PureSheets MONO: $499/5mg Ningbo Morsh 300 tons (from August 2013) 5000 RMB Yuan ($730) per gram-3 RMB Yuan per gram Vorbeck Materials Corporation 40 tons plus Vor-ink : $ USD per 500g XG Sciences, Inc. 80 tons $199/kg Xiamen Knano Graphene Approximately 50 tons Graphene nanoplatelets: $60,000 per ton. Xolve 500 Kg $500-$5000 per Kg 14

15 GRAPHENE PRODUCTION explosive with high risk of toxic gas release. Such processes may be low cost however, scaling to large volumes is a significant challenge. Various other processes have been reported that use super-acids mixed with hydrogen peroxide to exfoliate graphite powders. These types of process are low cost with acceptable yield of production however, the process is extremely dangerous due to use of very strong acids and high risk of explosion. Government restriction severely restrict processes that use strong acids. Furthermore such processes are not green (there are several issues regarding consumables residue) and the resulting Graphene does not show a great degree of biocompatibility. An optimal production process for Graphene is a green one, with no acid or oxidizer involved, with no risk of explosion or toxic gas release, and with a high yield of production (scalable). Exfoliation processes have the same challenges as above, but the challenges are minimized in part by the simplicity of the overall process. This is especially true for those processes that avoid the use of super acids. However, for exfoliation processes, another difficulty is the washing and purification process for graphite. Using centrifuges to remove large graphite particles from exfoliated ones hinders the scalability of the process and using sonicators to reduce the number of layers of Graphene dramatically reduces its sheet size. Developing techniques that do not require these post-processing steps definitely improves scalability. Large consumer electronic producers such as Samsung and IBM are leaders in this segment, and several other companies involved include Graphenea, Graphene Frontiers, as well as CVD system producers such as CVD Equipment and Aixtron. CVD-grown graphene is produced in greater quantities and cheaper but can suffer from significantly poorer quality, especially for highperformance electronics applications. However, not all graphene applications require high quality graphene. The price of CVD graphene is linked to production volume and costs of transferring from the copper substrate, on which it is grown, onto another substrate. Another attractive production option is to utilize greenhouse pollutant gases and naturally occurring and recyclable minerals to produce high quality Graphene. One such process has been developed by Graphene Technologies (High Temperature Physics, LLC), USA. The company is planning to launch Graphene and intermediate products under the brand name GraphenX. 15

16 GRAPHENE PRODUCTION The most appealing feature of this process is that it utilizes low cost, widely available carbon dioxide gas or other carbon bearing feedstock materials. Such processes utilize a highly exothermic reaction occurring between magnesium and CO2, and thereby, substantially reduces the energy requirement for the production of Graphene. Another feature of this technology is that it recycles the important materials, including Mg feedstock and HCl employed in the separation and purification of reaction products. The quality of Graphene produced by the various techniques described above can vary widely. Quality For Graphene sheets, the presence of defects, impurities, grain boundaries, multiple domains, structural disorders, and wrinkles in the Graphene sheet can have an adverse effect on electronic and optical properties. Large, high quality Graphene sheets are currently only possible with CVD processes, but even these process struggle to produce high quality and single crystalline Graphene thin films possessing very high electrical and thermal conductivities along with excellent optical transparency, as well as clean etching and lithography of Graphene thin films. For applications that are less sensitive to high electrical conduction, where spray-coated Graphene from powder source is the solution, requirements are much less stringent. Hence exfoliation techniques from graphite that end up with Graphene in powder format are currently the most viable techniques to commercialize Graphene, but the Graphene produced is not suitable for all applications. Graphene oxide Among these, the production of graphite oxide (GO) from graphite powder and its further reduction (through chemical, thermal, or ultraviolet-assisted reduction methods) to graphene-like material is a convenient and cheap way of graphene-like sheet fabrication. There are challenges of how to realize large-scale fabrication of highquality graphene materials and large-size single crystal graphene domains, which are essential for mass applications and device applications since grain boundaries are believed to markedly degrade the quality and properties of graphene. The cost of graphene is linked to its production method and subsequent quality. The best quality of graphene (pristine, defect-free ultrahigh quality graphene) currently available commercially costs around $1500 m 2. There are a number of companies producing graphene to this quality. Graphene oxide powder Graphene oxide powder (graphene functionalized with oxygen and hydrogen) is inexpensive and has been used to make a conductive graphene paper and also as a filler in advanced composites. However, the electronic properties of graphene oxide are not acceptable for application in batteries, flexible touch screens, solar cells, LEDs, smart windows, and other advanced opto-electronic applications. Oversupply Production capacity of graphene currently exceeds demand and this will continue to be the case until costs are reduced and applications become more prevalent. Within 5-10 years, graphene prices may drop below that of silicon allowing graphene to be directly competitive in computing, sensor and solar cell applications. Graphene is a prime candidate flexible smartphones as silicon is brittle and will break upon bending. Scalability and cost Scalability and cost of production are currently the most important factors limiting the commercialization of Graphene. The cost of producing Graphene is falling dramatically as techniques improve. In 2008, it was estimated that it would cost $100M to produce a square centimetre. In 2012, price estimates ranged from $200K a square centimetre for ultra-high quality material, to $20 for a lower quality sample of the same size. A recent ParisTech Review article (September, 2013) estimated production costs for Graphene at $800/g, while many industry participants suggest that successful commercialization of Graphene requires a final price of about $10/g for high quality and pure Graphene in large sheets. The major hurdle in manufacturing Graphene on an industrial scale is process complexity and the associated high cost of its production, which results in an expensive product. Production costs vary depending upon the cost of chemical consumables and process complexity. The best quality of graphene (pristine, defect-free ultra-high quality graphene) currently available commercially costs around $1500 m 2. There are a number of companies producing graphene to this quality. 16

17 NANOTUBES Competing against nanotubes Many of the current and potential applications of carbon nanotubes may be taken by graphene as it displays enhanced properties but with greater ease of production and handling. In this regard, carbon nanotubes may be viewed as a stalking horse for commercial applications of graphene. However, in an interesting development, using carbon nanotubes and graphene in combination shows great promise, allowing for greater consistency and higher concentrations of these materials in the end product. Compared with CNTs, with the quasi one-dimensional (1D) structure, graphene has an ideal two-dimensional (2D) structure. It has a higher surface area and similar conductivity for electrochemical applications, but it can be produced at a much lower cost. Thus graphene has advantages in scalable device fabrication via top-down approaches, which is compatible with the existing semiconductor fabrication technology. Composite-quality graphene has the potential to be a lot cheaper than nanotubes, although costs are currently similar. Graphene also has the advantage of greater ease of dispersion in resins than nanotubes. As they are two-dimensional and have very low aspect ratio (height to length ratio), the entanglement problems faced with rival materials such as carbon nanotubes, carbon nanofibers and nanoclays do not arise in the use of graphene in polymer nanocomposites. Also, since two-dimensional platelets of graphene can slide over each other, it does not increase the viscosity of the resin in the molten state. Apart from their easier incorporation and processing advantages, graphene is much cheaper than carbon nanotubes. Its widespread industrial uptake/application is arguably more realistic, and potential greater than that of carbon nanotubes. Despite considerable recent progress with carbon nanotubes and other nanoscale fillers, the development of strong, durable, and costefficient multifunctional nanocomposite materials has yet to be achieved. Advantages of graphene over carbon nanotubes stem from easy access to the graphitic precursor material, the cost, and the scalable method. Graphene polymer, ceramic matrix composites display potential for the development of paper-like materials but with unusual mechanical properties. Graphene is far superior to carbon nanotubes or any other known nanofiller in transferring its exceptional strength and mechanical properties to a host material. Graphene however is still considerably more expensive than nanotubes and current production capacities are also smaller. Current production capacity for nanotubes is more than 4000 tons. A number of potential applications for graphene are similar to carbon nanotubes, especially for transparent conductive coatings to replace indium tin oxide. Table 8: Properties of carbon materials. Properties Fullerenes Carbon nanotubes Activated carbon Graphite Graphene Specific surface area (m 2 /g) ~ Thermal conductivity (W/m K) Intrinsic mobility (cm 2/V s) 0.4 > 3000 (multiwalled carbon nanotube) ~3000 (inplane values) 0.56 ~100,000 ~13000 (inplane values) ~15,000 (in-plane values onto SiO2 surface) ~200,000 (freestanding) Young s modulus (TPa) ~1.0 Optical transparency (%) ~

18 A number of potential applications for graphene are similar to carbon nanotubes, especially for transparent conductive coatings to replace indium tin oxide. Other applications where they are competing are in batteries, composites and sensors. In the United States there were 1926 U.S. patent applications for graphene filed in 2012, in comparison to 3049 CNT patents. As well as competing against nanotubes for certain applications, nanowires and other established materials such as carbon fiber and silicon, graphene also faces competition from other 2D materials such as boron nitride, molybdenum disulfide, tungsten disulfide, niobium diselenide and tantalum (IV) sulphide) and germanane. These materials have theoretically exceptional electrical properties such as electronic band gaps, that graphene lacks. Carbyne is another recent discovery that has been calculated to be stronger than graphene ( abs/ ). CNTs and graphene show potential for working in conjunction. The growth of vertically aligned carbon nanotube (CNT) forests is highly sensitive to the nature of the substrate. Using a suspended monolayer, we show here that graphene is an excellent conductive substrate for CNT forest growth ( com/srep/2013/130528/srep01891/full/ srep01891.html). It has also been reported that CNTs can be transformed into a superelastic material by coating it with between one and five layers of graphene nanoplates ( journal/v7/n9/full/nnano html). The EU-funded SANAD project is combining graphene with carbon nanotubes to make a repellent coating for aircraft. Graphene producers can learn significantly from the experience of CNT producers. Issues CNT producers have experienced in terms of quality, scale, and price also apply to graphene producers. 18

19 GRAPHENE PATENTS Graphene Patents & Publications There has been a significant increase in the number of graphene patents in the past few years. In 2010, 230 of the published U.S. patent applications mentioned graphene in the abstract or claims. In 2009, this number was only 113; in 2008 it was only 31; and 2007 only provided 24. As of 2011, there were over 10,000 research papers on graphene. Evidence of the Graphene opportunity was highlighted by the Intellectual Property Office (IPO) in their recent report Graphene The worldwide patent landscape While Graphene is considered a British discovery (albeit by two eminent Russian Scientists based in Manchester), of the 8,416 patents published worldwide relating to Graphene by February 2013, only 57 were from the UK, while organisations in China, USA, Korea and Japan held almost 80% of the rest of the patents. Many of these related to potential applications of Graphene as opposed to the production of the base material. Given the predominance of uses relating to its conductivity and similar properties and as most of the ultra-capacitor and touch screen manufacturers are located in these countries, the patent proliferation in those territories is not surprising. Clearly therefore, based on the number of patents being applied on an almost daily basis, academia and industry think it can be made to work and are energetically pursuing ideas. Angstron Materials, XG Sciences and Vorbeck have all applied for patent protection of their own fabrication approaches. Due to the difficulty in patenting the generic production approaches however, intellectual property protection by patents is supplemented by the development of in-house, equipment specific know-how, related to questions of scaling up and efficiency of the production method. The most prolific patentees in graphene are in academia, often in conjunction with multinational companies. Samsung and Sandisk have the largest corporate patent portfolios in graphene, mainly related to semiconductor and data storage applications. Companies in the USA, South Korea and China lead the way in the number of patents filed over the past five years for graphene applications. By April 2013, Chinese companies and research institutes had 2,204 patent publications, followed by U.S. entities with 1,754, then South Korea with 1,160. The UK owned 54 filed patents. The world s top graphene patent owners are (listed alphabetically): International Business Machines (IBM) Korea Advanced Institute of Science and Technology (KAIST) Rice University (William Marsh) Samsung (South Korea) Sandisk 3D LLC Sungyunkwan University Tsinghua University Xerox Corp Zhejiang University. Samsung has filed over 400 patents to date as it is looking to apply graphene to TVs and mobile devices. Table 9: Published patent publications for graphene, Year Number of patents

20 PRODUCT INTEGRATION Graphene Product Integration Graphene has the potential to greatly improve future products, but the timing and path to these innovative products will depend upon the adaptability of Graphene and its compounds to end user production processes and the ability of Graphene producers to explain the value of Graphene to all the industrial and manufacturing players in the products supply chain. Graphene is poised to impact a wide range of industries and promises to make significant improvements to consumers lives as it is incorporated into processes and products. In order for Graphene to meets its potential however, low cost production processes must be developed, these production processes must be both scalable and suitable for integration into existing manufacturing processes and regulations, and the challenges of integrating Graphene into products, either as Graphene compounds or Graphene components, must be met. Great strides have been made meeting all these goals over the last few years as a broad range of players have pushed ahead simultaneously on many different fronts. It is still difficult to predict the exact shape of the coming Graphene industry, but regardless of the details for the world at large the benefits of Graphene will soon be enjoyed widely. Carbon nanomaterials This is a golden era for carbon research with the academics pursuing the perfect analysis tools for these nanomaterials whilst simultaneously evaluating the growing variants of each sub family and how they must be processed to ensure their potential properties are married to the systems they could enhance. Recognition of the cost benefit of each graphene family almost seems outside the scope of researchers yet must be realised by industry if they are to grasp the enormous potential benefits being offered. There is a massive education process required combining realistic appraisal with the removal of any hype. Often in the race for sales and profit, nanomaterials have been pushed onto the market as the one for you only for the user to find that it was no different from or indeed worse than, say, the materials already being used. It is likely that the blame actually lies with impure materials having defects/voids or the wrong surface chemistry. Apart from the technical errors, all marketing gurus will advise never sell or try to force into the market a product that has just been discovered or invented rather than finding what the market wants and delivering a solution. Figure 1: Graphene powders from Vorbeck Materials. Graphene in the supply chain In rough terms, Graphene is likely to enter the supply chain as either a compound - Graphene integrated with another material - or as a component - for example, a Graphene layer in a semiconductor structure. Graphene-based compounds are mixtures of Graphene with, for example, polymers, metals, or ceramics. Mixture of Graphene with other materials brings distinctive characteristics-however, mixing is a complex process. Dispersion In the case of Graphene-polymer composites, dispersibility is the main disadvantage. The challenge is to find suitable solvents that have a high degree of solubility for both the Graphene and selected polymer. Graphene is not soluble in aqueous media and represents limited solubility in organic solvents in which polymers are soluble. Mixing Graphene with ceramics is much easier, but currently relatively limited applications are foreseen for resulting compounds. Graphene composites with metals and alloys suffer from weak bonding in the atomic interface. This results in weak thermal conduction after adding Graphene to say aluminium or titanium. Theoretically such compounds should demonstrate an enhanced thermal conduction however, in practice, tuning the mixing process has proved quite difficult. The key to this is the ability to properly surface engineer the Graphene nanomaterials so that they can co- 20

21 PRODUCT INTEGRATION valently bond with the target matrix in a way that ensures homogeneous dispersion. Dispersion is the real key to delivering excellent conductivity, thermal heat transfer, barrier films that out-perform current offerings, a workable transparent conductive film, conductive inks and so on. This is not new. In a paper entitled The mechanics of graphene nano composites: A review published in July 2012 ( manchester.ac.uk/uk-ac-manscw:173015) by four Manchester University Scientists (including Novoselov) concluded that: Graphene and Graphene Oxide show promise as reinforcements in high-performance nanocomposites and ought to have outstanding mechanical properties. BUT there are problems in: Obtaining good dispersions Exfoliation of Graphene into single- or few-layer material with reasonable lateral dimensions Producing Graphene without imparting significant damage upon the flakes. The commercial picture is complicated by the fact that there are many different types of Graphene and many target markets. Each type of Graphene offers a different set of properties depending on the form in which it arrives; the average flake size, the number of Graphene layers, and the chemical groups existing on the surface of the flakes. Similarly, each target market also requires different performance levels and cost targets, along with goto-market strategies. The picture is further complicated by the fact that there are many production techniques, and each technique delivers a different material, cost structure and scalability. No wonder the research departments are struggling to find the material that both works for their application and fulfils their other criteria. Requirements It needs; a strong interface between the reinforcement and the polymer matrix to obtain the optimum mechanical and conductive properties. To date, the industrial world has tried many methods and some are further ahead than others. Judging by the claims of those making Graphenes, the future supply of the base material will not be the problem, certainly for the multi-layered GNP, while no one really knows when the single commercially available Graphene sheet will be available. In whatever form the supply is, dispersing it properly to make a real improvement will be the issue. The current use of chemical and thermal shocking in the conversion of powdered graphite to GNP has scalability but creates defects and is limited by the chemical groups available in the intercalating acids. Leaving aside the environmental aspects, these powders can be produced relatively cheaply until there is a need to add a dispersing agent or some other process to achieve the desired dispersion. Whilst this has met with some success the treatment has cost implications and damages the very structure you are trying to disperse into a material. Additionally the surface chemical the treatment leaves on the Graphenes is limited to the groups inherent in the available acids. Synthetically produced Graphenes are almost certainly going to have to overcome the same issues of dispersions. Some companies remain very coy and even silent in this respect. Carbon, after all, is relatively inert and thus is difficult to bond to and to disperse. Adding free radicals to the surface of the carbons can help in: Exfoliating (or liberating) sheets; Enhancing particle segregation; Improving dispersion; and Enabling tailored solutions Production Several companies focus on low cost production of such Graphene compounds and own patents on Graphene-related products. These companies typically aim to partner with larger companies closer to the end user, or manufacturers from other industries which could make use of Graphene and its compounds. The leading incumbents manufacturers in various industries have started to expand in this direction as well and are evaluating the feasibility of incorporating Graphene compounds into their products. Graphene component companies include very large players such as IBM and Samsung, as well as smaller companies such as AMO GmbH Aachen and Bluestone Global Tech and others. Many of these are focused on electronic, electro-optical and semiconductor type applications. Vorbeck Materials is also working with major apparel manufacturers to bring smart clothing, utilizing a line of grapheneenabled wearable electronics, to mass market in The challenge for these players is to bring the benefits of Graphene to existing, complex and multistage manufacturing processes. However, these manufacturing processes are stable and very well understood and so successful integration of Graphene is highly likely eventually. 21

22 PRODUCT INTEGRATION Commercialization Commercialization of Graphene requires a deep knowledge of various industries with strong grasp on how each industry produces the targeted product. Figure 2: Vorbeck Materials Vor-ink- TM conductive electronics printed through flexographic techniques. the single film perfect Graphene sheets by the Far East giants of Samsung, LG and others, there is an interesting alternative. How can we capitalise on the less perfect but equally effective Graphene Nano Platelet (GNP) as a key to short term commercialisation? Each product in each industry has its own unique production techniques and Graphene integration must adapt to such processes. An example is temperature. Graphene normally decomposes at high temperatures, severely limiting its integration in existing production process with high temperature steps. Unless Graphene can be modified to tolerate high temperature processes, it will be very difficult for it to enter into many sectors - such as casting and other heavy industries - where high temperature processes are common. The science is complex and as some cynics have put it, Graphenes advanced properties give it unrivalled ability to separate investors and their money. Industry and academia will need to collaborate closely to prove them wrong! How will this happen when often taking an idea from the lab to the industrial world is littered with debris of failing companies and lost money. Fantastic material properties on a lab scale do not always translate into large scale applications that can be made economically. In the case of CNT, if the industrial giant Bayer decided to stop investing in the technology, how can it be achieved with Graphene? Whilst long term efforts are being made to produce on an industrial scale, 22

23 Graphene market supply chain Table 10: Graphene market supply chain Tier Supply Chain and Companies 1 Graphite Producers (Northern Graphite Corporation, Focus Graphite Inc., American Graphite Technologies Inc.) Sales directly to graphene producers 1 Tools and equipment providers (Aixtron, Nanotek Instrument, CVD Equipment Corporation) Sales to manufacturers and application developers 2 Research Labs (University of Manchester, Rice University) Development of production methods Collaboration with materials companies and product developers 3 Graphene Manufacturers (Angstron Materials, Durham Graphene Science, Graphene Industries Ltd., Graphene Devices Ltd., Nanointegris, Graphene Works, Inc., Vorbeck Materials Corporation, XG Sciences, Inc., Xolve) Sales directly to application developers or via distributors (Cheaptubes, Graphene Supermarket, Reade etc.) Joint collaboration with OEMs and Application Developers Sales directly to OEMs Universities and research centers 4 Intermediate developers (Dupont, Unidym, Hanwha Chemical, BASF, Bayer, Zyvex, DOW Chemical, Solvay, CTI Nanotechnologies) Application developers/large Materials Companies Purchase nanomaterials from producers and incorporate into products Produce materials in-house or in collaboration with materials producers/research centres Collaboration with OEMs to develop final product Direct sales to markets 5 Application developers (Nissan Motor Co., NASA, LG Electronics, Samsung, Boeing, 3M, GE, Locheed Martin, Fujitsu, IBM, Nokia, BAE Systems, Siemens, Airbus, ST Microelectronics, Alcatel-Lucent, Antolin, Bosch, Fiat, Onera, Philips, Repsol, Volvo) Develop products in house-materials purchased from graphene producers Develop products in collaboration with intermediate developers Direct sales to end user markets 23

24 MARKET Electronics Graphene has remarkable electronic properties, with an extraordinarily high charge carrier mobility and conductivity. It is an excellent conductor, and transports electrons tens of times faster than silicon. These properties make it an ideal candidate for next generation electronic applications. Near-term electronics applications for graphene are in radio-frequency identification tags, low-resolution displays and backlights, sensors, electrical contacts, analog signal processing and electronics packaging. Initially applications will be in low-end electronics, depending on the manufacturing cost. High-end electronics applications are also cost sensitive. MARKET POTENTIAL APPLICATIONS AND ESTI- MATED TIME TO MARKET l Graphene RFID tags (Current) l Conductive inks in displays (1 year) l Carbon Semiconductors (8 years plus) Touch Screens OLEDs Conductive ink Graphene is being developed as a potential replacement for the costly indium tin oxide (ITO) in touch screens. ITO is brittle, making it unsuitable for flexible touch screens. A network of graphene nanostructures provides an inexpensive alternative, which is also flexible and stretchable. Samsung is the main technology developer in this area. A number of companies are planning on having graphene in touchscreens by the end of MARKET POTENTIAL Graphene shows potential in transparent conductive electrodes in OLEDs due to its controllable transparency, good electrical conductivity and tunable work function. There has been extensive research on the use of graphene as transparent electrodes for the purposes of both replacing ITO and also developing flexible OLEDs. In particular, graphene have a molecular structure similar to that of organic electronic materials, and thus can form strong bonds with organic electronic materials. MARKET POTENTIAL Most conductive inks on the market are made from expensive silver particles. They also have to be heattreated after they re applied, which means they can t be printed on polymers and other heat-sensitive materials. Graphene ink requires no heat treatment and is more conductive than other carbon-based alternatives to silver inks. BASF is developing graphene inks for electronics applications along with Vorbeck Materials. MARKET POTENTIAL 24

25 The development of future flexible and transparent electronics relies on novel materials, which are mechanically flexible, lightweight and low-cost, in addition to being electrically conductive and optically transparent. The demand for transparent conductors is expected to grow rapidly as electronic devices, such as touch screens, displays, solid state lighting and photovoltaics become ubiquitous. TRANSPARENT CONDUCTORS Current global market size: Transparent electrode market $15 billion plus. Developmental stage: On market in Graphene is being developed as a potential replacement for indium tin oxide (ITO) in touchscreens, which is the dominant transparent conductor in the electronics market. ITO has a market share of more than 97% of transparent conducting coatings, but it is expensive, there are difficulties in the fabrication steps and it is becoming increasingly scarce as global indium supply dwindles. ITO is also mechanically rigid, making it unsuitable for future flexible electronics applications. As a result, non-ito transparent conductors such as graphene are coming increasingly to the fore. Applications for transparent conductors include touch sensors, displays, lighting, thin-film solar (PV), smart windows, and EMI shielding. There are around 200 companies and research institutions currently developing ITO alternatives such as metal meshes, silver nanowires, conductive polymers, carbon nanotubes, other 2-D materials and GaN. However, graphene is at the forefront of this growing market. A network of graphene nanostructures provides an inexpensive alternative to ITO, and is also flexible and stretchable. Graphene oxide films can be deposited on virtually any substrate, and later converted into a conductor. Therefore it is expected that transparent graphene films may replace rigid and brittle ITO films in touch panel screen electrodes. Developments in 2013/2014 March Researchers from EPFL design a new flash memory cell prototype that is made from graphene and Molybdenite (MoS 2 ). The new design is efficient, flexible, small and fast. The concept is that the unique electronic properties of MoS 2 are combined with graphene s excellent conductivity. nn May Korean researchers develop a new blue nitride LED that uses 3D graphene foam as a transparent conductor for the p-contact. They claim that the graphene foam reduced the forward voltage by 26% and increased the light output by 14%. doi/ /