Potential applications of graphene
This article needs to be updated.December 2013)(
Potential graphene applications include lightweight, thin, and flexible electric/photonics circuits, solar cells, and various medical, chemical and industrial processes enhanced or enabled by the use of new graphene materials.
In 2008, graphene produced by exfoliation was one of the most expensive materials on Earth, with a sample the area of a cross section of a human hair costing more than $1,000 as of April 2008 (about $100,000,000/cm2). Since then, exfoliation procedures have been scaled up, and now companies sell graphene in large quantities. The price of epitaxial graphene on silicon carbide is dominated by the substrate price, which was approximately $100/cm2 as of 2009. Hong and his team in South Korea pioneered the synthesis of large-scale graphene films using chemical vapour deposition (CVD) on thin nickel layers, which triggered research on practical applications, with wafer sizes up to 760 millimetres (30 in) reported. By 2017, graphene electronics were being manufactured in a commercial fab on a 200 mm line.
In 2013, the European Union made a €1 billion grant to be used for research into potential graphene applications. In 2013 the Graphene Flagship consortium formed, including Chalmers University of Technology and seven other European universities and research centers, along with Nokia.
In 2015 researchers used graphene to create biosensors with epitaxial graphene on silicon carbide. The sensors bind to 8-hydroxydeoxyguanosine (8-OHdG) and is capable of selective binding with antibodies. The presence of 8-OHdG in blood, urine and saliva is commonly associated with DNA damage. Elevated levels of 8-OHdG have been linked to increased risk of several cancers. By the next year, a commercial version of a graphene biosensor was being used by biology researchers as a protein binding sensor platform.
In 2016 researchers revealed that uncoated graphene can be used as neuro-interface electrode without altering or damaging properties such as signal strength or formation of scar tissue. Graphene electrodes in the body are significantly more stable than electrodes of tungsten or silicon because of properties such as flexibility, bio-compatibility and conductivity.
Graphene has been investigated for tissue engineering. It has been used as a reinforcing agent to improve the mechanical properties of biodegradable polymeric nanocomposites for engineering bone tissue applications. Dispersion of low weight % of graphene (≈0.02 wt.%) increased in compressive and flexural mechanical properties of polymeric nanocomposites. The addition of graphene nanoparticles in the polymer matrix lead to improvements in the crosslinking density of the nanocomposite and better load transfer from the polymer matrix to the underlying nanomaterial thereby increasing the mechanical properties.
Contrast agents, bioimaging
Functionalized and surfactant dispersed graphene solutions have been designed as blood pool MRI contrast agents. Further, iodine and manganese incorporating graphene nanoparticles have served as multimodal MRI-computerized tomograph (CT) contrast agents. Graphene micro- and nano-particles have served as contrast agents for photoacoustic and thermoacoustic tomography. Graphene has also been reported to be efficiently taking up cancerous cells thereby enabling the design of drug delivery agents for cancer therapy. Graphene nanoparticles of various morphologies such as graphene nanoribbons, graphene nanoplatelets and graphene nanoonions[clarification needed] are non-toxic at low concentrations and do not alter stem cell differentiation suggesting that they may be safe to use for biomedical applications.
Polymerase chain reaction
Graphene is reported to have enhanced PCR by increasing the yield of DNA product. Experiments revealed that graphene's thermal conductivity could be the main factor behind this result. Graphene yields DNA product equivalent to positive control with up to 65% reduction in PCR cycles.
Graphene's modifiable chemistry, large surface area per unit volume, atomic thickness and molecularly gatable structure make antibody-functionalized graphene sheets excellent candidates for mammalian and microbial detection and diagnosis devices. Graphene is so thin that water has near-perfect wetting transparency which is an important property particularly in developing bio-sensor applications. This means that a sensor coated in graphene has as much contact with an aqueous system as an uncoated sensor, while remaining protected mechanically from its environment.
In 2014, graphene-based, transparent (across infrared to ultraviolet frequencies), flexible, implantable medical sensor microarrays were announced that allow the viewing of brain tissue hidden by implants. Optical transparency was greater than 90%. Applications demonstrated include optogenetic activation of focal cortical areas, in vivo imaging of cortical vasculature via fluorescence microscopy and 3D optical coherence tomography.
Researchers at Monash University discovered that a sheet of graphene oxide can be transformed into liquid crystal droplets spontaneously—like a polymer—simply by placing the material in a solution and manipulating the pH. The graphene droplets change their structure in the presence of an external magnetic field. This finding raises the possibility of carrying a drug in graphene droplets and releasing the drug upon reaching the targeted tissue by making the droplets change shape in a magnetic field. Another possible application is in disease detection if graphene is found to change shape at the presence of certain disease markers such as toxins.
A graphene ‘flying carpet’ was demonstrated to deliver two anti-cancer drugs sequentially to the lung tumor cells (A549 cell) in a mouse model. Doxorubicin (DOX) is embedded onto the graphene sheet, while the molecules of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) are linked to the nanostructure via short peptide chains. Injected intravenously, the graphene strips with the drug payload preferentially concentrate to the cancer cells due to common blood vessel leakage around the tumor. Receptors on the cancer cell membrane bind TRAIL and cell surface enzymes clip the peptide thus release the drug onto the cell surface. Without the bulky TRAIL, the graphene strips with the embedded DOX are swallowed into the cells. The intracellular acidic environment promotes DOX's release from graphene. TRAIL on the cell surface triggers the apoptosis while DOX attacks the nucleus. These two drugs work synergistically and were found to be more effective than either drug alone.
The development of nanotechnology and molecular biology has provided the improvement of nanomaterials with speciﬁc properties which are now able to overcome the weaknesses of traditional disease diagnostic and therapeutic procedures. In recent years, more attention has been devoted to designing and the development of new methods for realizing sustained release of diverse drugs. Since each drug has a plasma level above which is toxic and below which is ineﬀective and in conventional drug delivery, the drug concentration in the blood rises quickly and then declines, the main aim of an ideal drug delivery system (DDS) is to maintain the drug within a desired therapeutic range after a single dose, and/or target the drug to a speciﬁc region while simultaneously lowering the systemic levels of the drug. Graphene–based materials such as graphene oxide (GO) have considerable potential for several biological applications including the development of new drug release system. GOs are an abundance of functional groups such as hydroxyl, epoxy, and carboxyl on its basal surface and edges that can be also used to immobilize or load various biomolecules for biomedical applications. On the other side, biopolymers have frequently been used as raw materials for designing drug delivery formulations owing to their excellent properties, such as non-toxicity, biocompatibility, biodegradability and environmental sensitivity, etc. Protein therapeutics possess advantages over small molecule approaches including high target speciﬁcity and low oﬀ target eﬀects with normal biological processes. Human serum albumin (HSA) is one of the most abundant blood proteins. It serves as a transport protein for several endogenous and exogenous ligands as well as various drug molecules. HSA nanoparticles have long been the center of attention in the pharmaceutical industry due to their ability to bind to various drug molecules, high storage stability and in vivo application, non–toxicity and antigenicity, biodegradability, reproducibility, scale–up of the production process and a better control over release properties. In addition, signiﬁcant amounts of drugs can be incorporated into the particle matrix because of the large number of drug binding sites on the albumin molecule. Therefore, the combination of HSA-NPs and GO-NSs could be useful for reducing the cytotoxicity of GO-NSs and the enhancement of drug loading and sustained drug release in cancer therapy.
Researchers demonstrated a nanoscale biomicrorobot (or cytobot) made by cladding a living endospore cell with graphene quantum dots. The device acted as a humidity sensor.
The toxicity of graphene has been extensively debated in the literature. The most comprehensive review on graphene toxicity published by Lalwani et al. summarizes current knowledge of the in vitro, in vivo, antimicrobial, and environmental toxicities of graphene, and highlights the various mechanisms of graphene toxicity. Results show that the toxicity of graphene is dependent on several factors such as shape, size, purity, post-production processing steps, oxidative state, functional groups, dispersion state, synthesis methods, route and dose of administration, and exposure times.
Graphene has a high carrier mobility, and low noise, allowing it to be used as the channel in a field-effect transistor. Unmodified graphene does not have an energy band gap, making it unsuitable for digital electronics. However, modifications (e.g. Graphene nanoribbons) have created potential uses in various areas of electronics.
Graphene transistors have been built that are chemically controlled, and others that are voltage controlled.
Graphene exhibits a pronounced response to perpendicular external electric fields, potentially forming field-effect transistors (FET). A 2004 paper documented FETs with an on-off ratio of ≈30 at room temperature. A 2006 paper announced an all-graphene planar FET with side gates. Their devices showed changes of 2% at cryogenic temperatures. The first top-gated FET (on–off ratio of <2) was demonstrated in 2007. Graphene nanoribbons may prove generally capable of replacing silicon as a semiconductor.
US patent 7015142 for graphene-based electronics was issued in 2006. In 2008, researchers at MIT Lincoln Lab produced hundreds of transistors on a single chip and in 2009, very high frequency transistors were produced at Hughes Research Laboratories.
A 2008 paper demonstrated a switching effect based on a reversible chemical modification of the graphene layer that gives an on–off ratio of greater than six orders of magnitude. These reversible switches could potentially be employed in nonvolatile memories. In 2008, the smallest transistor so far, one atom thick, 10 atoms wide was made of graphene. IBM announced in December 2008 that they had fabricated and characterized graphene transistors operating at GHz frequencies.
In 2009, researchers demonstrated four different types of logic gates, each composed of a single graphene transistor. In May 2009, an n-type transistor was announced meaning that both n and p-type graphene transistors had been created. A functional graphene integrated circuit was demonstrated—a complementary inverter consisting of one p- and one n-type graphene transistor. However, this inverter suffered from a very low voltage gain. Typically, the amplitude of the output signal is about 40 times less than that of the input signal. Moreover, none of these circuits operated at frequencies higher than 25 kHz.
In the same year, tight-binding numerical simulations demonstrated that the band-gap induced in graphene bilayer field effect transistors is not sufficiently large for high-performance transistors for digital applications, but can be sufficient for ultra-low voltage applications, when exploiting a tunnel-FET architecture.
In February 2010, researchers announced graphene transistors with an on-off rate of 100 gigahertz, far exceeding the rates of prior attempts, and exceeding the speed of silicon transistors with an equal gate length. The 240 nm devices were made with conventional silicon-manufacturing equipment. According to a January 2010 report, graphene was epitaxially grown on SiC in a quantity and with quality suitable for mass production of integrated circuits. At high temperatures, the quantum Hall effect could be measured in these samples. IBM built 'processors' using 100 GHz transistors on 2-inch (51 mm) graphene sheets.
In June 2011, IBM researchers announced that they had succeeded in creating the first graphene-based integrated circuit, a broadband radio mixer. The circuit handled frequencies up to 10 GHz. Its performance was unaffected by temperatures up to 127 °C. In November researchers used 3d printing (additive manufacturing) as a method for fabricating graphene devices.
In 2013, researchers demonstrated graphene's high mobility in a detector that allows broad band frequency selectivity ranging from the THz to IR region (0.76–33 THz) A separate group created a terahertz-speed transistor with bistable characteristics, which means that the device can spontaneously switch between two electronic states. The device consists of two layers of graphene separated by an insulating layer of boron nitride a few atomic layers thick. Electrons move through this barrier by quantum tunneling. These new transistors exhibit negative differential conductance, whereby the same electric current flows at two different applied voltages. In June, an 8 transistor 1.28 GHz ring oscillator circuit was described.
The negative differential resistance experimentally observed in graphene field-effect transistors of conventional design allows for construction of viable non-Boolean computational architectures with graphene. The negative differential resistance—observed under certain biasing schemes—is an intrinsic property of graphene resulting from its symmetric band structure. The results present a conceptual change in graphene research and indicate an alternative route for graphene's applications in information processing.
In 2013 researchers created transistors printed on flexible plastic that operate at 25 gigahertz, sufficient for communications circuits and that can be fabricated at scale. The researchers first fabricated non-graphene-containing structures—the electrodes and gates—on plastic sheets. Separately, they grew large graphene sheets on metal, then peeled it and transferred it to the plastic. Finally, they topped the sheet with a waterproof layer. The devices work after being soaked in water, and are flexible enough to be folded.
In 2015 researchers devised a digital switch by perforating a graphene sheet with boron-nitride nanotubes that exhibited a switching ratio of 105 at a turn-on voltage of 0.5 V. Density functional theory suggested that the behavior came from the mismatch of the density of states.
An electric field can change trilayer graphene's crystal structure, transforming its behavior from metal-like into semiconductor-like. A sharp metal scanning tunneling microscopy tip was able to move the domain border between the upper and lower graphene configurations. One side of the material behaves as a metal, while the other side behaves as a semiconductor. Trilayer graphene can be stacked in either Bernal or rhombohedral configurations, which can exist in a single flake. The two domains are separated by a precise boundary at which the middle layer is strained to accommodate the transition from one stacking pattern to the other.
Silicon transistors function as either p-type or n-type semiconductors, whereas graphene could operate as both. This lowers costs and is more versatile. The technique provides the basis for a field-effect transistor. Scalable manufacturing techniques have yet to be developed.
In trilayer graphene, the two stacking configurations exhibit very different electronic properties. The region between them consists of a localized strain soliton where the carbon atoms of one graphene layer shift by the carbon–carbon bond distance. The free-energy difference between the two stacking configurations scales quadratically with electric field, favoring rhombohedral stacking as the electric field increases.
Graphene-based transistors could be much thinner than modern silicon devices, allowing faster and smaller configurations.
Transparent conducting electrodes
Graphene's high electrical conductivity and high optical transparency make it a candidate for transparent conducting electrodes, required for such applications as touchscreens, liquid crystal displays, inorganic photovoltaics cells, organic photovoltaic cells, and organic light-emitting diodes. In particular, graphene's mechanical strength and flexibility are advantageous compared to indium tin oxide, which is brittle. Graphene films may be deposited from solution over large areas.
Large-area, continuous, transparent and highly conducting few-layered graphene films were produced by chemical vapor deposition and used as anodes for application in photovoltaic devices. A power conversion efficiency (PCE) up to 1.7% was demonstrated, which is 55.2% of the PCE of a control device based on indium tin oxide. However, the main disadvantage brought by the fabrication method will be the poor substrate bondings that will eventually lead to poor cyclic stability and cause high resistivity to the electrodes.
Organic light-emitting diodes (OLEDs) with graphene anodes have been demonstrated. The device was formed by solution-processed graphene on a quartz substrate. The electronic and optical performance of graphene-based devices are similar to devices made with indium tin oxide. In 2017 OLED electrodes were produced by CVD on a copper substrate.
A carbon-based device called a light-emitting electrochemical cell (LEC) was demonstrated with chemically-derived graphene as the cathode and the conductive polymer Poly(3,4-ethylenedioxythiophene) (PEDOT) as the anode. Unlike its predecessors, this device contains only carbon-based electrodes, with no metal.
In 2014 a prototype graphene-based flexible display was demonstrated.
In 2016 researchers demonstrated a display that used interferometry modulation to control colors, dubbed a "graphene balloon device" made of silicon containing 10 μm circular cavities covered by two graphene sheets. The degree of curvature of the sheets above each cavity defines the color emitted. The device exploits the phenomena known as Newton's rings created by interference between light waves bouncing off the bottom of the cavity and the (transparent) material. Increasing the distance between the silicon and the membrane increased the wavelength of the light. The approach is used in colored e-reader displays and smartwatches, such as the Qualcomm Toq. They use silicon materials instead of graphene. Graphene reduces power requirements.
Graphene strongly interacts with photons, with the potential for direct band-gap creation. This is promising for optoelectronic and nanophotonic devices. Light interaction arises due to the Van Hove singularity. Graphene displays different time scales in response to photon interaction, ranging from femtoseconds (ultra-fast) to picoseconds. Potential uses include transparent films, touch screens and light emitters or as a plasmonic device that confines light and alters wavelengths.
Hall effect sensors
Due to extremely high electron mobility, graphene may be used for production of highly sensitive Hall effect sensors. Potential application of such sensors is connected with DC current transformers for special applications. New record high sensitive Hall sensors are reported in April 2015. These sensors are two times better than existing Si based sensors.
Graphene quantum dots (GQDs) keep all dimensions less than 10 nm. Their size and edge crystallography govern their electrical, magnetic, optical, and chemical properties. GQDs can be produced via graphite nanotomy or via bottom-up, solution-based routes (Diels-Alder, cyclotrimerization and/or cyclodehydrogenation reactions). GQDs with controlled structure can be incorporated into applications in electronics, optoelectronics and electromagnetics. Quantum confinement can be created by changing the width of graphene nanoribbons (GNRs) at selected points along the ribbon. It is studied as a catalyst for fuel cells.
A semiconducting polymer (poly(3-hexylthiophene) placed on top of single-layer graphene vertically conducts electric charge better than on a thin layer of silicon. A 50 nm thick polymer film conducted charge about 50 times better than a 10 nm thick film, potentially because the former consists of a mosaic of variably-oriented crystallites forms a continuous pathway of interconnected crystals. In a thin film or on silicon, plate-like crystallites are oriented parallel to the graphene layer. Uses include solar cells.
Large-area graphene created by chemical vapor deposition (CVD) and layered on a SiO2 substrate, can preserve electron spin over an extended period and communicate it. Spintronics varies electron spin rather than current flow. The spin signal is preserved in graphene channels that are up to 16 micrometers long over a nanosecond. Pure spin transport and precession extended over 16 μm channel lengths with a spin lifetime of 1.2 ns and a spin diffusion length of ≈6 μm at room temperature.
Spintronics is used in disk drives for data storage and in magnetic random-access memory. Electronic spin is generally short-lived and fragile, but the spin-based information in current devices needs to travel only a few nanometers. However, in processors, the information must cross several tens of micrometers with aligned spins. Graphene is the only known candidate for such behavior.
In 2012 Vorbeck Materials started shipping the Siren anti-theft packaging device, which uses their graphene-based Vor-Ink circuitry to replace the metal antenna and external wiring to an RFID chip. This was the world's first commercially available product based on graphene.
When the Fermi level of graphene is tuned, its optical absorption can be changed. In 2011, researchers reported the first graphene-based optical modulator. Operating at 1.2 GHz without a temperature controller, this modulator has a broad bandwidth (from 1.3 to 1.6 μm) and small footprint (~25 μm2).
A Mach-Zehnder modulator based on a hybrid graphene-silicon waveguide has been demonstrated recently, which can process signals nearly chirp-free. An extinction up to 34.7 dB and a minimum chirp parameter of -0.006 are obtained. Its insertion loss is roughly -1.37 dB.
A hyperlens is a real-time super-resolution lens that can transform evanescent waves into propagating waves and thus break the diffraction limit. In 2016 a hyperlens based on dielectric layered graphene and h-boron nitride (h-BN) can surpass metal designs. Based on its anisotropic properties, flat and cylindrical hyperlenses were numerically verified with layered graphene at 1200 THz and layered h-BN at 1400 THz, respectively. In 2016 a 1-nm thick graphene microlens that can image objects the size of a single bacterium. The lens was created by spraying a sheet of graphene oxide solution, then molding the lens using a laser beam. It can resolve objects as small as 200 nanometers, and see into the near infrared. It breaks the diffraction limit and achieve a focal length less than half the wavelength of light. Possible applications include thermal imaging for mobile phones, endoscopes, nanosatellites and photonic chips in supercomputers and superfast broadband distribution.
Infrared light detection
Graphene reacts to the infrared spectrum at room temperature, albeit with sensitivity 100 to 1000 times too low for practical applications. However, two graphene layers separated by an insulator allowed an electric field produced by holes left by photo-freed electrons in one layer to affect a current running through the other layer. The process produces little heat, making it suitable for use in night-vision optics. The sandwich is thin enough to be integrated in handheld devices, eyeglass-mounted computers and even contact lenses.
A graphene/n-type silicon heterojunction has been demonstrated to exhibit strong rectifying behavior and high photoresponsivity. By introducing a thin interfacial oxide layer, the dark current of graphene/n-Si heterojunction has been reduced by two orders of magnitude at zero bias. At room temperature, the graphene/n-Si photodetector with interfacial oxide exhibits a specific detectivity up to 5.77 × 1013 cm Hz1/2 W2 at the peak wavelength of 890 nm in vacuum. In addition, the improved graphene/n-Si heterojunction photodetectors possess high responsivity of 0.73 A W−1 and high photo-to-dark current ratio of ≈107. These results demonstrate that graphene/Si heterojunction with interfacial oxide is promising for the development of high detectivity photodetectors. Recently, a graphene/si Schottky photodetector with record-fast response speed (< 25 ns) from wavelength 350 nm to 1100 nm are presented. The photodetectors exhibit excellent long-term stability even stored in air for more than 2 years. These results not only advance the development of high-performance photodetectors based on the graphene/Si Schottky junction, but also have important implications for mass-production of graphene-based photodetector array devices for cost-effective environmental monitoring, medical images, free-space communications, photoelectric smart-tracking, and integration with CMOS circuits for emerging interest-of-things applications, etc.
Graphene oxide membranes allow water vapor to pass through, but are impermeable to other liquids and gases. This phenomenon has been used for further distilling of vodka to higher alcohol concentrations, in a room-temperature laboratory, without the application of heat or vacuum as used in traditional distillation methods.
Graphene solar cells use graphene's unique combination of high electrical conductivity and optical transparency. This material absorbs only 2.6% of green light and 2.3% of red light. Graphene can be assembled into a film electrode with low roughness. These films must be made thicker than one atomic layer to obtain useful sheet resistances. This added resistance can be offset by incorporating conductive filler materials, such as a silica matrix. Reduced conductivity can be offset by attaching large aromatic molecules such as pyrene-1-sulfonic acid sodium salt (PyS) and the disodium salt of 3,4,9,10-perylenetetracarboxylic diimide bisbenzenesulfonic acid (PDI). These molecules, under high temperatures, facilitate better π-conjugation of the graphene basal plane.
Using graphene as a photoactive material requires its bandgap to be 1.4–1.9 eV. In 2010, single cell efficiencies of nanostructured graphene-based PVs of over 12% were achieved. According to P. Mukhopadhyay and R. K. Gupta organic photovoltaics could be "devices in which semiconducting graphene is used as the photoactive material and metallic graphene is used as the conductive electrodes".
In 2008, chemical vapor deposition produced graphene sheets by depositing a graphene film made from methane gas on a nickel plate. A protective layer of thermoplastic is laid over the graphene layer and the nickel underneath is then dissolved in an acid bath. The final step is to attach the plastic-coated graphene to a flexible polymer sheet, which can then be incorporated into a PV cell. Graphene/polymer sheets range in size up to 150 square centimeters and can be used to create dense arrays.
Silicon generates only one current-driving electron for each photon it absorbs, while graphene can produce multiple electrons. Solar cells made with graphene could offer 60% conversion efficiency.
In 2010, researchers first reported creating a graphene-silicon heterojunction solar cell, where graphene served as a transparent electrode and introduced a built-in electric field near the interface between the graphene and n-type silicon to help collect charge carriers. In 2012 researchers reported efficiency of 8.6% for a prototype consisting of a silicon wafer coated with trifluoromethanesulfonyl-amide (TFSA) doped graphene. Doping increased efficiency to 9.6% in 2013. In 2015 researchers reported efficiency of 15.6% by choosing the optimal oxide thickness on the silicon. This combination of carbon materials with traditional silicon semiconductors to fabricate solar cells has been a promising field of carbon science.
In 2013, another team reported 15.6% percent by combining titanium oxide and graphene as a charge collector and perovskite as a sunlight absorber. The device is manufacturable at temperatures under 150 °C (302 °F) using solution-based deposition. This lowers production costs and offers the potential using flexible plastics.
In 2015, researchers developed a prototype cell that used semitransparent perovskite with graphene electrodes. The design allowed light to be absorbed from both sides. It offered efficiency of around 12 percent with estimated production costs of less than $0.06/watt. The graphene was coated with PEDOT:PSS conductive polymer (polythiophene) polystyrene sulfonate). Multilayering graphene via CVD created transparent electrodes reducing sheet resistance. Performance was further improved by increasing contact between the top electrodes and the hole transport layer.
Appropriately perforated graphene (and hexagonal boron nitride hBN) can allow protons to pass through it, offering the potential for using graphene monolayers as a barrier that blocks hydrogen atoms but not protons/ionized hydrogen (hydrogen atoms with their electrons stripped off). They could even be used to extract hydrogen gas out of the atmosphere that could power electric generators with ambient air.
Graphene could solve a major problem for fuel cells: fuel crossover that reduces efficiency and durability.
In methanol fuel cells, graphene used as a barrier layer in the membrane area, has reduced fuel cross over with negligible proton resistance, improving the performance.
At room temperature, proton conductivity with monolayer hBN, outperforms graphene, with resistivity to proton flow of about 10 Ω cm2 and a low activation energy of about 0.3 electronvolts. At higher temperatures, graphene outperforms with resistivity estimated to fall below 10−3 Ω cm2 above 250 degrees Celsius.
In another project, protons easily pass through slightly imperfect graphene membranes on fused silica in water. The membrane was exposed to cycles of high and low pH. Protons transferred reversibly from the aqueous phase through the graphene to the other side where they undergo acid–base chemistry with silica hydroxyl groups. Computer simulations indicated energy barriers of 0.61–0.75 eV for hydroxyl-terminated atomic defects that participate in a Grotthuss-type relay, while pyrylium-like ether terminations did not. Recently, Paul and co-workers at IISER Bhopal demonstrated solid state proton conduction for oxygen functionalized few-layer graphene (8.7x10−3 S/cm) with a low activation barrier (0.25 eV).
Adding 0.6% graphene to a mixture of lanthanum and partly reduced strontium titanium oxide produces a strong Seebeck at temperatures ranging from room temperature to 750 °C (compared to 500–750 without graphene). The material converts 5% of the heat into electricity (compared to 1% for strontium titanium oxide.)
In 2015 a graphene coating on steam condensers quadrupled condensation efficiency, increasing overall plant efficiency by 2–3 percent.
In 2015 the technique was adapted to produce stacked, 3-D supercapacitors. Laser-induced graphene was produced on both sides of a polymer sheet. The sections were then stacked, separated by solid electrolytes, making multiple microsupercapacitors. The stacked configuration substantially increased the energy density of the result. In testing, the researchers charged and discharged the devices for thousands of cycles with almost no loss of capacitance. The resulting devices were mechanically flexible, surviving 8,000 bending cycles. This makes them potentially suitable for rolling in a cylindrical configuration. Solid-state polymeric electrolyte-based devices exhibit areal capacitance of >9 mF/cm2 at a current density of 0.02 mA/cm2, over twice that of conventional aqueous electrolytes.
Also in 2015 another project announced a microsupercapacitor that is small enough to fit in wearable or implantable devices. Just one-fifth the thickness of a sheet of paper, it is capable of holding more than twice as much charge as a comparable thin-film lithium battery. The design employed laser-scribed graphene, or LSG with manganese dioxide. They can be fabricated without extreme temperatures or expensive “dry rooms”. Their capacity is six times that of commercially available supercapacitors. The device reached volumetric capacitance of over 1,100 F/cm3. This corresponds to a specific capacitance of the constituent MnO2 of 1,145 F/g, close to the theoretical maximum of 1,380 F/g. Energy density varies between 22 and 42 Wh/l depending on device configuration.
In May 2015 a boric acid-infused, laser-induced graphene supercapacitor tripled its areal energy density and increased its volumetric energy density 5-10 fold. The new devices proved stable over 12,000 charge-discharge cycles, retaining 90 percent of their capacitance. In stress tests, they survived 8,000 bending cycles.
Stable Lithium ion cycling was demonstrated in bi- and few layer graphene films grown on nickel substrates, while single layer graphene films have been demonstrated as a protective layer against corrosion in battery components such as the battery case. This creates possibilities for flexible electrodes for microscale Li-ion batteries, where the anode acts as the active material and the current collector.
In 2015 argon-ion based plasma processing was used to bombard graphene samples with argon ions. That knocked out some carbon atoms and increased the capacitance of the materials three-fold. These “armchair” and “zigzag” defects are named based on the configurations of the carbon atoms that surround the holes.
In 2016, Huawei announced graphene-assisted Lithium-Ion batteries with greater heat tolerance and twice the life span of traditional Lithium-Ion batteries, the component with the shortest life span in mobile phones.
Graphene does not oxidize in air or in biological fluids, making it an attractive material for use as a biosensor. A graphene circuit can be configured as a field effect biosensor by applying biological capture molecules and blocking layers to the graphene, then controlling the voltage difference between the graphene and the liquid that includes the biological test sample. Of the various types of graphene sensors that can be made, biosensors were the first to be available for sale.
The electronic properties of graphene/h-BN heterostructures can be modulated by changing the interlayer distances via applying external pressure, leading to potential realization of atomic thin pressure sensors. In 2011 researchers proposed an in-plane pressure sensor consisting of graphene sandwiched between hexagonal boron nitride and a tunneling pressure sensor consisting of h-BN sandwiched by graphene. The current varies by 3 orders of magnitude as pressure increases from 0 to 5 nN/nm². This structure is insensitive to the number of wrapping h-BN layers, simplifying process control. Because h-BN and graphene are inert to high temperature, the device could support ultra-thin pressure sensors for application under extreme conditions.
Nanoelectromechanical systems (NEMS) can be designed and characterized by understanding the interaction and coupling between the mechanical, electrical, and the van der Waals energy domains. Quantum mechanical limit governed by Heisenberg uncertainty relation decides the ultimate precision of nanomechanical systems. Quantum squeezing can improve the precision by reducing quantum fluctuations in one desired amplitude of the two quadrature amplitudes. Traditional NEMS hardly achieve quantum squeezing due to their thickness limits. A scheme to obtain squeezed quantum states through typical experimental graphene NEMS structures taking advantages of its atomic scale thickness has been proposed.
Theoretically graphene makes an excellent sensor due to its 2D structure. The fact that its entire volume is exposed to its surrounding environment makes it very efficient to detect adsorbed molecules. However, similar to carbon nanotubes, graphene has no dangling bonds on its surface. Gaseous molecules cannot be readily adsorbed onto graphene surfaces, so intrinsically graphene is insensitive. The sensitivity of graphene chemical gas sensors can be dramatically enhanced by functionalization, for example, coating the film with a thin layer of certain polymers. The thin polymer layer acts like a concentrator that absorbs gaseous molecules. The molecule absorption introduces a local change in electrical resistance of graphene sensors. While this effect occurs in other materials, graphene is superior due to its high electrical conductivity (even when few carriers are present) and low noise, which makes this change in resistance detectable.
Density functional theory simulations predict that depositing certain adatoms on graphene can render it piezoelectrically responsive to an electric field applied in the out-of-plane direction. This type of locally engineered piezoelectricity is similar in magnitude to that of bulk piezoelectric materials and makes graphene a candidate for control and sensing in nanoscale devices.
Promoted by the demand for wearable devices, graphene has been proved to be a promising material for potential applications in flexible and highly sensitive strain sensors. An environment-friendly and cost-effective method to fabricate large-area ultrathin graphene films is proposed for highly sensitive flexible strain sensor. The assembled graphene films are derived rapidly at the liquid/air interface by Marangoni effect and the area can be scaled up. These graphene-based strain sensors exhibit extremely high sensitivity with gauge factor of 1037 at 2% strain, which represents the highest value for graphene platelets at this small deformation so far.
Rubber bands infused with graphene ("G-bands") can be used as inexpensive body sensors. The bands remain pliable and can be used as a sensor to measure breathing, heart rate, or movement. Lightweight sensor suits for vulnerable patients could make it possible to remotely monitor subtle movement. These sensors display 10×104-fold increases in resistance and work at strains exceeding 800%. Gauge factors of up to 35 were observed. Such sensors can function at vibration frequencies of at least 160 Hz. At 60 Hz, strains of at least 6% at strain rates exceeding 6000%/s can be monitored.
In 2015 researchers announced a graphene-based magnetic sensor 100 times more sensitive than an equivalent device based on silicon (7,000 volts per amp-tesla). The sensor substrate was hexagonal boron nitride. The sensors were based on the Hall effect, in which a magnetic field induces a Lorentz force on moving electric charge carriers, leading to deflection and a measurable Hall voltage. In the worst case graphene roughly matched a best case silicon design. In the best case graphene required lower source current and power requirements.
Graphene oxide is non-toxic and biodegradable. Its surface is covered with epoxy, hydroxyl, and carboxyl groups that interact with cations and anions. It is soluble in water and forms stable colloid suspensions in other liquids because it is amphiphilic (able to mix with water or oil). Dispersed in liquids it shows excellent sorption capacities. It can remove copper, cobalt, cadmium, arsenate, and organic solvents.
Instead of allowing the permeation, blocking is also necessary. Gas permeation barriers are important for almost all applications ranging from food, pharmaceutical, medical, inorganic and organic electronic devices, etc. packaging. It extends the life of the product and allows keeping the total thickness of devices small. Being atomically thin, defectless graphene is impermeable to all gases. In particular, ultra-thin moisture permeation barrier layers based on graphene are shown to be important for organic-FETs and OLEDs. Graphene barrier applications in biological sciences are under study.
Plasmonics and metamaterials
Graphene accommodates a plasmonic surface mode, observed recently via near field infrared optical microscopy techniques and infrared spectroscopy  Potential applications are in the terahertz to mid-infrared frequencies, such as terahertz and midinfrared light modulators, passive terahertz filters, mid-infrared photodetectors and biosensors.
Scientists discovered using graphene as a lubricant works better than traditionally used graphite. A one atom thick layer of graphene in between a steel ball and steel disc lasted for 6,500 cycles. Conventional lubricants lasted 1,000 cycles.
Radio wave absorption
Stacked graphene layers on a quartz substrate increased the absorption of millimeter (radio) waves by 90 per cent over 125–165 GHz bandwidth, extensible to microwave and low-terahertz frequencies, while remaining transparent to visible light. For example, graphene could be used as a coating for buildings or windows to block radio waves. Absorption is a result of mutually coupled Fabry–Perot resonators represented by each graphene-quartz substrate. A repeated transfer-and-etch process was used to control surface resistivity.
Graphene oxide can be reversibly reduced and oxidized via electrical stimulus. Controlled reduction and oxidation in two-terminal devices containing multilayer graphene oxide films are shown to result in switching between partly reduced graphene oxide and graphene, a process that modifies electronic and optical properties. Oxidation and reduction are related to resistive switching.
A graphene-based plasmonic nano-antenna (GPN) can operate efficiently at millimeter radio wavelengths. The wavelength of surface plasmon polaritons for a given frequency is several hundred times smaller than the wavelength of freely propagating electromagnetic waves of the same frequency. These speed and size differences enable efficient graphene-based antennas to be far smaller than conventional alternatives. The latter operate at frequencies 100–1000 times larger than GPNs, producing 0.01–0.001 as many photons.
An electromagnetic (EM) wave directed vertically onto a graphene surface excites the graphene into oscillations that interact with those in the dielectric on which the graphene is mounted, thereby forming surface plasmon polaritons (SPP). When the antenna becomes resonant (an integral number of SPP wavelengths fit into the physical dimensions of the graphene), the SPP/EM coupling increases greatly, efficiently transferring energy between the two.
A phased array antenna 100 µm in diameter could produce 300 GHz beams only a few degrees in diameter, instead of the 180 degree radiation from tsa conventional metal antenna of that size. Potential uses include smart dust, low-power terabit wireless networks and photonics.
A nanoscale gold rod antenna captured and transformed EM energy into graphene plasmons, analogous to a radio antenna converting radio waves into electromagnetic waves in a metal cable. The plasmon wavefronts can be directly controlled by adjusting antenna geometry. The waves were focused (by curving the antenna) and refracted (by a prism-shaped graphene bilayer because the conductivity in the two-atom-thick prism is larger than in the surrounding one-atom-thick layer.)
The plasmonic metal-graphene nanoantenna was composed by inserting a few nanometers of oxide between a dipole gold nanorod and the monolayer graphene. The used oxide layer here can reduce the quantum tunelling effect between graphene and metal antenna. With tuning the chemical potential of the graphene layer through field effect transistor architecture, the in-phase and out-phase mode coupling between graphene palsmonics and metal plasmonics is realized. The tunable properties of the plasmonic metal-graphene nanoantenna can be switched on and off via modifying the electrostatic gate-voltage on graphene.
Graphene's light weight provides relatively good frequency response, suggesting uses in electrostatic audio speakers and microphones. In 2015 an ultrasonic microphone and speaker were demonstrated that could operate at frequencies from 20 Hz–500 kHz. The speaker operated at a claimed 99% efficiency with a flat frequency response across the audible range. One application was as a radio replacement for long-distance communications, given sound's ability to penetrate steel and water, unlike radio waves.
Graphene's high thermal conductivity suggests that it could be used as an additive in coolants. Preliminary research work showed that 5% graphene by volume can enhance the thermal conductivity of a base fluid by 86%. Another application due to graphene's enhanced thermal conductivity was found in PCR.
This property was used to define the conductivity of transparency that combines sheet resistance and transparency. This parameter was used to compare materials without the use of two independent parameters.
In 2011, researchers reported that a three-dimensional, vertically aligned, functionalized multilayer graphene architecture can be an approach for graphene-based thermal interfacial materials (TIMs) with superior thermal conductivity and ultra-low interfacial thermal resistance between graphene and metal.
Graphene-metal composites can be used in thermal interface materials.
Adding a layer of graphene to each side of a copper film increased the metal's heat-conducting properties up to 24%. This suggests the possibility of using them for semiconductor interconnects in computer chips. The improvement is the result of changes in copper's nano- and microstructure, not from graphene's independent action as an added heat conducting channel. High temperature chemical vapor deposition stimulates grain size growth in copper films. The larger grain sizes improve heat conduction. The heat conduction improvement was more pronounced in thinner copper films, which is useful as copper interconnects shrink.
Attaching graphene functionalized with silane molecules increases its thermal conductivity (κ) by 15–56% with respect to the number density of molecules. This is because of enhanced in-plane heat conduction resulting from the simultaneous increase of thermal resistance between the graphene and the substrate, which limited cross-plane phonon scattering. Heat spreading ability doubled.
However, mismatches at the boundary between horizontally adjacent crystals reduces heat transfer by a factor of 10.
Graphene's strength, stiffness and lightness suggested it for use with carbon fiber. Graphene has been used as a reinforcing agent to improve the mechanical properties of biodegradable polymeric nanocomposites for engineering bone tissue.
In 2014, researchers at the University of Western Australia discovered nano sized fragments of graphene can speed up the rate of chemical reactions. In 2015, researchers announced an atomic scale catalyst made of graphene doped with nitrogen and augmented with small amounts of cobalt whose onset voltage was comparable to platinum catalysts. In 2016 iron-nitrogen complexes embedded in graphene were reported as another form of catalyst. The new material was claimed to approach the efficiency of platinum catalysts. The approach eliminated the need for less efficient iron nanoparticles.
In 2016, researchers developed a prototype de-icing system that incorporated unzipped carbon nanotube graphene nanoribbons in an epoxy/graphene composite. In laboratory tests, the leading edge of a helicopter rotor blade was coated with the composite, covered by a protective metal sleeve. Applying an electrical current heated the composite to over 200 °F (93 °C), melting a 1 cm (0.4 in)-thick ice layer with ambient temperatures of a -4 °F (-20 °C).
- Monie, Sanjay. "Developments in Conductive Inks". Industrial & Specialty Printing. Archived from the original on April 14, 2014. Retrieved April 26, 2010.
- Geim, A. K.; Kim, P. (April 2008). "Carbon Wonderland". Scientific American.
... bits of graphene are undoubtedly present in every pencil mark
- Segal, M. (2009). "Selling graphene by the ton". Nature Nanotechnology. 4 (10): 612–14. Bibcode:2009NatNa...4..612S. doi:10.1038/nnano.2009.279. PMID 19809441.
- Patel, P. (January 15, 2009). "Bigger, Stretchier Graphene". MIT Technology Review.
- Bae, S.; et al. (2010). "Roll-to-roll production of 30-inch graphene films for transparent electrodes". Nature Nanotechnology. 5 (8): 574–78. Bibcode:2010NatNa...5..574B. CiteSeerX 10.1.1.176.439. doi:10.1038/nnano.2010.132. PMID 20562870.
- "Graphene biosensors – finally a commercial reality". www.newelectronics.co.uk. Retrieved August 9, 2017.
- "Europa – Press Release – Graphene and Human Brain Project win largest research excellence award in history, as battle for sustained science funding continues". Europa.eu. January 28, 2013.
- Thomson, Iain. "Nokia shares $1.35bn EU graphene research grant". The Register.
"FET Graphene Flagship". Graphene-flagship.eu. Archived from the original on August 5, 2013. Retrieved August 24, 2013.
- Nayak, Tapas R.; Andersen, Henrik; Makam, Venkata S.; Khaw, Clement; Bae, Sukang; Xu, Xiangfan; Ee, Pui-Lai R.; Ahn, Jong-Hyun; Hong, Byung Hee; Pastorin, Giorgia; Özyilmaz, Barbaros (May 11, 2011). "Graphene for Controlled and Accelerated Osteogenic Differentiation of Human Mesenchymal Stem Cells". ACS Nano. 5 (6): 4670–78. arXiv:1104.5120. Bibcode:2011arXiv1104.5120N. doi:10.1021/nn200500h. PMID 21528849. S2CID 20794090.
- Tehrani, Z; Burwell, G; Azmi, M A Mohd; Castaing, A; Rickman, R; Almarashi, J; Dunstan, P; Beigi, A Miran; Doak, S H; Guy, O J (September 19, 2014). "Generic epitaxial graphene biosensors for ultrasensitive detection of cancer risk biomarker" (PDF). 2D Materials. 1 (2): 025004. Bibcode:2014TDM.....1b5004T. doi:10.1088/2053-1583/1/2/025004.
- Qvit, Nir; Disatnik, Marie-Hélène; Sho, Eiketsu; Mochly-Rosen, Daria (June 8, 2016). "Selective Phosphorylation Inhibitor of Delta Protein Kinase C–Pyruvate Dehydrogenase Kinase Protein–Protein Interactions: Application for Myocardial Injury". Journal of the American Chemical Society. 138 (24): 7626–35. doi:10.1021/jacs.6b02724. PMC 5065007. PMID 27218445.
- "Graphene shown to safely interact with neurons in the brain". University of Cambridge. January 29, 2016. Retrieved February 16, 2016.
- Lalwani, Gaurav; Henslee, Allan M.; Farshid, Behzad; Lin, Liangjun; Kasper, F. Kurtis; Qin, Yi-Xian; Mikos, Antonios G.; Sitharaman, Balaji (February 27, 2013). "Two-Dimensional Nanostructure-Reinforced Biodegradable Polymeric Nanocomposites for Bone Tissue Engineering". Biomacromolecules. 14 (3): 900–09. doi:10.1021/bm301995s. PMC 3601907. PMID 23405887.
- Rafiee, M.A.; et al. (December 3, 2009). "Enhanced Mechanical Properties of Nanocomposites at Low Graphene Content". ACS Nano. 3 (12): 3884–90. doi:10.1021/nn9010472. PMID 19957928.
- Sitharaman, Balaji; Kanakia, Shruti; Toussaint, Jimmy; Mullick Chowdhury, Sayan; Lalwani, Gaurav; Tembulkar, Tanuf; Button, Terry; Shroyer, Kenneth; Moore (August 2013). "Physicochemical characterization of a novel graphene-based magnetic resonance imaging contrast agent". International Journal of Nanomedicine. 8: 2821–33. doi:10.2147/IJN.S47062. PMC 3742530. PMID 23946653.
- Lalwani, Gaurav; Sundararaj, Joe Livingston; Schaefer, Kenneth; Button, Terry; Sitharaman, Balaji (2014). "Synthesis, characterization, in vitro phantom imaging, and cytotoxicity of a novel graphene-based multimodal magnetic resonance imaging-X-ray computed tomography contrast agent". J. Mater. Chem. B. 2 (22): 3519–30. doi:10.1039/C4TB00326H. PMC 4079501. PMID 24999431.
- Lalwani, Gaurav; Cai, Xin; Nie, Liming; Wang, Lihong V.; Sitharaman, Balaji (December 2013). "Graphene-based contrast agents for photoacoustic and thermoacoustic tomography". Photoacoustics. 1 (3–4): 62–67. doi:10.1016/j.pacs.2013.10.001. PMC 3904379. PMID 24490141.
- Mullick Chowdhury, Sayan; Lalwani, Gaurav; Zhang, Kevin; Yang, Jeong Y.; Neville, Kayla; Sitharaman, Balaji (January 2013). "Cell specific cytotoxicity and uptake of graphene nanoribbons". Biomaterials. 34 (1): 283–93. doi:10.1016/j.biomaterials.2012.09.057. PMC 3489471. PMID 23072942.
- Talukdar, Yahfi; Rashkow, Jason T.; Lalwani, Gaurav; Kanakia, Shruti; Sitharaman, Balaji (June 2014). "The effects of graphene nanostructures on mesenchymal stem cells". Biomaterials. 35 (18): 4863–77. doi:10.1016/j.biomaterials.2014.02.054. PMC 3995421. PMID 24674462.
- Abdul Khaliq, R; Kafafy, R.; Salleh, H. M.; Faris, W. F. (2012). "Enhancing the efficiency of polymerase chain reaction using graphene nanoflakes". Nanotechnology. 23 (45): 455106. doi:10.1088/0957-4484/23/45/455106. PMID 23085573.
- Mohanty, Nihar; Berry, Vikas (2008). "Graphene-based Single-Bacterium Resolution Biodevice and DNA-Transistor – Interfacing Graphene-Derivatives with Nano and Micro Scale Biocomponents". Nano Letters. 8 (12): 4469–76. Bibcode:2008NanoL...8.4469M. doi:10.1021/nl802412n. PMID 19367973.
- Donaldson, L. (2012). "Graphene: Invisible to water". Materials Today. 15 (3): 82. doi:10.1016/S1369-7021(12)70037-8.
- Xu, M. S. Xu; Fujita, D.; Hanagata, N. (2009). "Perspectives and Challenges of Emerging Single-Molecule DNA Sequencing Technologies". Small. 5 (23): 2638–49. doi:10.1002/smll.200900976. PMID 19904762.
- "Bill Gates condom challenge 'to be met' by graphene scientists". BBC News. November 20, 2013.
- Park, Dong-Wook; et al. (October 20, 2014). "Graphene-based carbon-layered electrode array technology for neural imaging and optogenetic applications". Nature Communications. 5: 5258. Bibcode:2014NatCo...5.5258P. doi:10.1038/ncomms6258. PMC 4218963. PMID 25327513.
- "Transparent graphene-based sensors open new window into the brain". KurzweilAI. October 21, 2014. Retrieved February 26, 2017.
- Press Release (August 6, 2014). "Surprise discovery could see graphene used to improve health". Monash University. Archived from the original on August 12, 2014.
- Majumder, M; Tkacz, R; Oldenbourg, R; Mehta, S; Miansari, M; Verma, A (2014). "pH dependent isotropic to nematic phase transitions in graphene oxide dispersions reveal droplet liquid crystalline phases". Chemical Communications. 50 (50): 6668–71. doi:10.1039/C4CC00970C. hdl:1912/6739. PMID 24828948.
- Press Release (January 6, 2015). "'Flying Carpet' Technique Uses Graphene to Deliver One-Two Punch of Anticancer Drugs". North Carolina State University.
- Gu, Zhen; et al. (December 15, 2014). "Furin-Mediated Sequential Delivery of Anticancer Cytokine and Small-Molecule Drug Shuttled by Graphene". Advanced Materials. 27 (6): 1021–28. doi:10.1002/adma.201404498. PMC 5769919. PMID 25504623. Cite uses deprecated parameter
- Aliabadi, Majid; Shagholani, Hamidreza; Yunessnia lehi, Arash (May 2017). "Synthesis of a novel biocompatible nanocomposite of graphene oxide and magnetic nanoparticles for drug delivery". International Journal of Biological Macromolecules. 98: 287–291. doi:10.1016/j.ijbiomac.2017.02.012. ISSN 0141-8130.
- Blakney, Anna K.; Simonovsky, Felix I.; Suydam, Ian T.; Ratner, Buddy D.; Woodrow, Kim A. (August 2016). "Rapidly Biodegrading PLGA-Polyurethane Fibers for Sustained Release of Physicochemically Diverse Drugs". ACS Biomaterials Science & Engineering. 2 (9): 1595–1607. doi:10.1021/acsbiomaterials.6b00346. ISSN 2373-9878.
- Yu, Hui; Yang, Peng; Jia, Yongtang; Zhang, Yumei; Ye, Qiuying; Zeng, Simin (October 2016). "Regulation of biphasic drug release behavior by graphene oxide in polyvinyl pyrrolidone/poly(ε-caprolactone) core/sheath nanofiber mats". Colloids and Surfaces B: Biointerfaces. 146: 63–69. doi:10.1016/j.colsurfb.2016.05.052. ISSN 0927-7765.
- Weber, C; Coester, C; Kreuter, J; Langer, K (January 2000). "Desolvation process and surface characterisation of protein nanoparticles". International Journal of Pharmaceutics. 194 (1): 91–102. doi:10.1016/s0378-5173(99)00370-1. ISSN 0378-5173.
- Jeffrey, Colin (March 25, 2015). "Robobug: Scientists clad bacterium with graphene to make a working cytobot". Gizmag. Retrieved February 25, 2017.
- Martin, Steve (September 18, 2014). "Purdue-based startup scales up graphene production, develops biosensors and supercapacitors". Purdue University. Retrieved October 4, 2014.
- "Startup scales up graphene production, develops biosensors and supercapacitors". R&D Magazine. September 19, 2014. Retrieved October 4, 2014.
- Lalwani, Gaurav; D'Agati, Michael; Khan, Amit Mahmud; Sitharaman, Balaji (October 2016). "Toxicology of graphene-based nanomaterials". Advanced Drug Delivery Reviews. 105 (Pt B): 109–44. doi:10.1016/j.addr.2016.04.028. PMC 5039077. PMID 27154267.
- Chen, J.; Ishigami, M.; Jang, C.; Hines, D. R.; Fuhrer, M. S.; Williams, E. D. (2007). "Printed graphene circuits". Advanced Materials. 19 (21): 3623–27. arXiv:0809.1634. doi:10.1002/adma.200701059. S2CID 14818151.
- "Carbon-Based Electronics: Researchers Develop Foundation for Circuitry and Devices Based on Graphite". March 14, 2006. Archived from the original on April 14, 2009. Retrieved April 13, 2014.
- Lemme, M. C.; Echtermeyer, Tim J.; et al. (2007). "A graphene field-effect device". IEEE Electron Device Letters. 28 (4): 282–84. arXiv:cond-mat/0703208. Bibcode:2007IEDL...28..282L. doi:10.1109/LED.2007.891668. S2CID 14555382. Cite uses deprecated parameter
- Bullis, K. (January 28, 2008). "Graphene Transistors". Cambridge: MIT Technology Review, Inc.
- Kedzierski, J.; Hsu, Pei-Lan; Healey, Paul; Wyatt, Peter W.; Keast, Craig L.; Sprinkle, Mike; Berger, Claire; De Heer, Walt A. (2008). "Epitaxial Graphene Transistors on SiC Substrates". IEEE Transactions on Electron Devices. 55 (8): 2078–85. arXiv:0801.2744. Bibcode:2008ITED...55.2078K. doi:10.1109/TED.2008.926593. S2CID 1176135.
- Moon, J.S.; Curtis, D.; Hu, M.; Wong, D.; McGuire, C.; Campbell, P.M.; Jernigan, G.; Tedesco, J.L.; Vanmil, B.; Myers-Ward, R.; Eddy, C.; Gaskill, D.K. (2009). "Epitaxial-Graphene RF Field-Effect Transistors on Si-Face 6H-SiC Substrates". IEEE Electron Device Letters. 30 (6): 650–52. Bibcode:2009IEDL...30..650M. doi:10.1109/LED.2009.2020699. S2CID 27018931.
- Echtermeyer, Tim. J.; Lemme, M.C.; et al. (2008). "Nonvolatile Switching in Graphene Field-Effect Devices". IEEE Electron Device Letters. 29 (8): 952–54. arXiv:0805.4095. Bibcode:2008IEDL...29..952E. doi:10.1109/LED.2008.2001179. S2CID 2096900. Cite uses deprecated parameter
- Ponomarenko, L. A.; Schedin, F.; Katsnelson, M. I.; Yang, R.; Hill, E. W.; Novoselov, K. S.; Geim, A. K. (2008). "Chaotic Dirac Billiard in Graphene Quantum Dots". Science. 320 (5874): 356–58. arXiv:0801.0160. Bibcode:2008Sci...320..356P. doi:10.1126/science.1154663. PMID 18420930. S2CID 206511356. Lay summary.
- "Graphene transistors clocked at 26 GHz Arxiv article". Arxivblog.com. December 11, 2008.
- Sordan, R.; Traversi, F.; Russo, V. (2009). "Logic gates with a single graphene transistor". Appl. Phys. Lett. 94 (7): 073305. Bibcode:2009ApPhL..94g3305S. doi:10.1063/1.3079663.
- Wang, X.; Li, X.; Zhang, L.; Yoon, Y.; Weber, P. K.; Wang, H.; Guo, J.; Dai, H. (2009). "N-Doping of Graphene Through Electrothermal Reactions with Ammonia". Science. 324 (5928): 768–71. Bibcode:2009Sci...324..768W. doi:10.1126/science.1170335. PMID 19423822. Lay summary.
- "Nanotechnology Information Center: Properties, Applications, Research, and Safety Guidelines". American Elements.
- Traversi, F.; Russo, V.; Sordan, R. (2009). "Integrated complementary graphene inverter". Appl. Phys. Lett. 94 (22): 223312. arXiv:0904.2745. Bibcode:2009ApPhL..94v3312T. doi:10.1063/1.3148342. S2CID 108877115. Lay summary.
- Fiori G., Iannaccone G., "On the possibility of tunable-gap bilayer graphene FET", IEEE Electr. Dev. Lett., 30, 261 (2009)
- Fiori G., Iannaccone G., "Ultralow-Voltage Bilayer graphene tunnel FET", IEEE Electr. Dev. Lett., 30, 1096 (2009)
- Bourzac, Katherine (February 5, 2010). "Graphene Transistors that Can Work at Blistering Speeds". MIT Technology Review.
- "IBM shows off 100GHz graphene transistor". Techworld News. Retrieved December 10, 2010.
- Lin; Dimitrakopoulos, C; Jenkins, KA; Farmer, DB; Chiu, HY; Grill, A; Avouris, P (2010). "100-GHz Transistors from Wafer-Scale Epitaxial Graphene". Science. 327 (5966): 662. arXiv:1002.3845. Bibcode:2010Sci...327..662L. doi:10.1126/science.1184289. PMID 20133565.
- "European collaboration breakthrough in developing graphene". NPL. January 19, 2010.
- Lin, Y.-M.; Dimitrakopoulos, C.; Jenkins, K. A.; Farmer, D. B.; Chiu, H.-Y.; Grill, A.; Avouris, Ph. (2010). "100-GHz Transistors from Wafer-Scale Epitaxial Graphene". Science. 327 (5966): 662. arXiv:1002.3845. Bibcode:2010Sci...327..662L. doi:10.1126/science.1184289. PMID 20133565.
- Lin, Y.-M.; Valdes-Garcia, A.; Han, S.-J.; Farmer, D. B.; Meric, I.; Sun, Y.; Wu, Y.; Dimitrakopoulos, C.; Grill, A.; Avouris, P.; Jenkins, K. A. (2011). "Wafer-Scale Graphene Integrated Circuit". Science. 332 (6035): 1294–97. Bibcode:2011Sci...332.1294L. doi:10.1126/science.1204428. PMID 21659599.
- Torrisi, F.; Hasan, T.; Wu, W.; Sun, Z.; Lombardo, A.; Kulmala, T.; Hshieh, G. W.; Jung, S. J.; Bonaccorso, F.; Paul, P. J.; Chu, D. P.; Ferrari, A. C. (2012). "Ink-Jet Printed Graphene Electronics". ACS Nano. 6 (2992): 2992–3006. arXiv:1111.4970. Bibcode:2011arXiv1111.4970T. doi:10.1021/nn2044609. PMID 22449258. S2CID 8624837.
- Kawano, Yukio (2013). "Wide-band frequency-tunable terahertz and infrared detection with graphene". Nanotechnology. 24 (21): 214004. Bibcode:2013Nanot..24u4004K. doi:10.1088/0957-4484/24/21/214004. PMID 23618878.
- Britnell, L.; Gorbachev, R. V.; Geim, A. K.; Ponomarenko, L. A.; Mishchenko, A.; Greenaway, M. T.; Fromhold, T. M.; Novoselov, K. S.; Eaves, L. (2013). "Radical new graphene design operates at terahertz speed". Nature Communications. 4 (4): 1794–. arXiv:1303.6864. Bibcode:2013NatCo...4E1794B. doi:10.1038/ncomms2817. PMC 3644101. PMID 23653206. Retrieved May 2, 2013.
Britnell, L.; Gorbachev, R. V.; Geim, A. K.; Ponomarenko, L. A.; Mishchenko, A.; Greenaway, M. T.; Fromhold, T. M.; Novoselov, K. S.; Eaves, L. (2013). "Resonant tunnelling and negative differential conductance in graphene transistors". Nature Communications. 4: 1794–. arXiv:1303.6864. Bibcode:2013NatCo...4.1794B. doi:10.1038/ncomms2817. PMC 3644101. PMID 23653206.
- Belle Dumé (June 17, 2013). "Graphene circuit breaks the gigahertz barrier". PhysicsWorld.
- Liu, Guanxiong; Ahsan, Sonia; Khitun, Alexander G.; Lake, Roger K.; Balandin, Alexander A. (2013). "Graphene-Based Non-Boolean Logic Circuits". Journal of Applied Physics. 114 (10): 154310–. arXiv:1308.2931. Bibcode:2013JAP...114o4310L. doi:10.1063/1.4824828. S2CID 7788774.
- Bourzac, Katherine. "Superfast, Bendable Electronic Switches Made from Graphene | MIT Technology Review". Technologyreview.com. Retrieved August 24, 2013.
- "Unlikely graphene-nanotube combination forms high-speed digital switch | KurzweilAI". kurzweilai.net. August 4, 2015. Retrieved February 26, 2017.
- "How to change the crystal structure of graphene from metal to semiconductor". KurzweilAI. May 6, 2014. Retrieved June 15, 2014.
- Yankowitz, M.; Wang, J. I. J.; Birdwell, A. G.; Chen, Y. A.; Watanabe, K.; Taniguchi, T.; Jacquod, P.; San-Jose, P.; Jarillo-Herrero, P.; Leroy, B. J. (2014). "Electric field control of soliton motion and stacking in trilayer graphene". Nature Materials. 13 (8): 786–89. arXiv:1401.7663. Bibcode:2014NatMa..13..786Y. doi:10.1038/nmat3965. PMID 24776537. S2CID 3812760.
- Jain, Nikhil; Bansal, Tanesh; Durcan, Christopher A.; Xu, Yang; Yu, Bin (2013). "Monolayer graphene/hexagonal boron nitride heterostructure". Carbon. 54: 396–402. doi:10.1016/j.carbon.2012.11.054.
- Li, Xiaoqiang; Chen, Wenchao; Zhang, Shengjiao; Wu, Zhiqian; Wang, Peng; Xu, Zhijuan; Chen, Hongsheng; Yin, Wenyan; Zhong, Huikai; Lin, Shisheng (September 2015). "18.5% efficient graphene/GaAs van der Waals heterostructure solar cell". Nano Energy. 16: 310–19. arXiv:1409.3500. doi:10.1016/j.nanoen.2015.07.003.
- Singh, Khomdram Jolson; Chettri, Dhanu; Singh, Thokchom Jayenta; Thingujam, Terirama; Sarkar, Subir kumar (June 2017). "A performance optimization and analysis of graphene based schottky barrier GaAs solar cell". IOP Conference Series: Materials Science and Engineering. 211 (1): 012024. Bibcode:2017MS&E..211a2024J. doi:10.1088/1757-899X/211/1/012024.
- Wang, Xuan; Zhi, Linjie; Müllen, Klaus (January 2008). "Transparent, Conductive Graphene Electrodes for Dye-Sensitized Solar Cells". Nano Letters. 8 (1): 323–27. Bibcode:2008NanoL...8..323W. doi:10.1021/nl072838r. PMID 18069877.
- Eda, Goki; Fanchini, Giovanni; Chhowalla, Manish (April 6, 2008). "Large-area ultrathin films of reduced graphene oxide as a transparent and flexible electronic material". Nature Nanotechnology. 3 (5): 270–74. doi:10.1038/nnano.2008.83. PMID 18654522.
- Wang, Shu Jun; Geng, Yan; Zheng, Qingbin; Kim, Jang-Kyo (May 2010). "Fabrication of highly conducting and transparent graphene films". Carbon. 48 (6): 1815–23. doi:10.1016/j.carbon.2010.01.027.
- Wang, Yu; Chen, Xiaohong; Zhong, Yulin; Zhu, Furong; Loh, Kian Ping (2009). "Large area, continuous, few-layered graphene as anodes in organic photovoltaic devices". Applied Physics Letters. 95 (6): 063302. Bibcode:2009ApPhL..95f3302W. doi:10.1063/1.3204698.
- Wu, J.B.; Agrawal, Mukul; Becerril, HéCtor A.; Bao, Zhenan; Liu, Zunfeng; Chen, Yongsheng; Peumans, Peter (2010). "Organic Light-Emitting Diodes on Solution-Processed Graphene Transparent Electrodes". ACS Nano. 4 (1): 43–48. doi:10.1021/nn900728d. PMID 19902961.
- Jeffrey, Colin (January 10, 2017). "First transparent OLED display with graphene electrodes created". newatlas.com. Retrieved February 17, 2017.
- Matyba, P.; Yamaguchi, H; et al. (2010). "Graphene and Mobile Ions: The Key to All-Plastic, Solution-Processed Light-Emitting Devices". ACS Nano. 4 (2): 637–42. CiteSeerX 10.1.1.474.2436. doi:10.1021/nn9018569. PMID 20131906. Cite uses deprecated parameter
- Jeffrey, Colin (September 11, 2014). "First flexible graphene-based display created". Gizmag. Retrieved February 26, 2017.
- Lavars, Nick (November 7, 2016). "More pop might be in store for e-readers thanks to colorful graphene balloons". newatlas.com. Retrieved April 30, 2017.
- Wang, H.; Nezich, D.; Kong, J.; Palacios, T. (2009). "Graphene Frequency Multipliers". IEEE Electron Device Letters. 30 (5): 547–49. Bibcode:2009IEDL...30..547H. doi:10.1109/LED.2009.2016443. hdl:1721.1/54736. S2CID 9317247. Lay summary.
Cricchio, D.; Corso, P. P.; Fiordilino, E.; Orlando, G.; Persico, F. (2009). "A paradigm of fullerene". J. Phys. B. 42 (8): 085404. Bibcode:2009JPhB...42h5404C. doi:10.1088/0953-4075/42/8/085404.
- Kusmartsev, F. V.; Wu, W. M.; Pierpoint, M. P.; Yung, K. C. (2014). "Application of Graphene within Optoelectronic Devices and Transistors". arXiv:1406.0809 [cond-mat.mtrl-sci].
- Petruk, O.; Szewczyk, R.; Ciuk, T.; et al. (2014). Sensitivity and Offset Voltage Testing in the Hall-Effect Sensors Made of Graphene. Advances in Intelligent Systems and Computing. 267. Springer. pp. 631–40. doi:10.1007/978-3-319-05353-0_60. ISBN 978-3-319-05352-3. Cite uses deprecated parameter
- Dauber, Jan; Sagade, Abhay A.; Oellers, Martin; Watanabe, Kenji; Taniguchi, Takashi; Neumaier, Daniel; Stampfer, Christoph; Ahn, Jong-Hyun; Byung Hee Hong; Pastorin, Giorgia; Özyilmaz, Barbaros (2015). "Ultra-sensitive Hall sensors based on graphene encapsulated in hexagonal boron nitride". Applied Physics Letters. 106 (19): 193501. arXiv:1504.01625. Bibcode:2015ApPhL.106s3501D. doi:10.1063/1.4919897. S2CID 118670440.
- Mohanty, Nihar; Moore, David; Xu, Zhiping; Sreeprasad, T. S.; Nagaraja, Ashvin; Rodriguez, Alfredo A.; Berry, Vikas (2012). "Nanotomy Based Production of Transferable and Dispersible Graphene-Nanostructures of Controlled Shape and Size". Nature Communications. 3 (5): 844. Bibcode:2012NatCo...3E.844M. doi:10.1038/ncomms1834. PMID 22588306.
- Jinming, Cai; Ruffieux, Pascal; Jaafar, Rached; Bieri, Marco; Braun, Thomas; Blankenburg, Stephan; Muoth, Matthias; Seitsonen, Ari P.; Saleh, Moussa; Feng, Xinliang; Müllen, Klaus; Fasel, Roman (2010). "Atomically precise bottom-up fabrication of graphene nanoribbons". Nature. 466 (7305): 470–73. Bibcode:2010Natur.466..470C. doi:10.1038/nature09211. PMID 20651687. S2CID 4422290.
- Wang, Z. F.; Shi, Q. W.; Li, Q.; Wang, X.; Hou, J. G.; Zheng, H.; Yao, Yao; Chen, Jie (2007). "Z-shaped graphene nanoribbon quantum dot device". Applied Physics Letters. 91 (5): 053109. arXiv:0705.0023. Bibcode:2007ApPhL..91e3109W. doi:10.1063/1.2761266.
- Fei, Huilong; Ye, Ruquan; Ye, Gonglan; Gong, Yongji; Peng, Zhiwei; Fan, Xiujun; Samuel, Errol L. G.; Ajayan, Pulickel M.; Tour, James M. (October 2014). "Boron- and Nitrogen-Doped Graphene Quantum Dots/Graphene Hybrid Nanoplatelets as Efficient Electrocatalysts for Oxygen Reduction". ACS Nano. 8 (10): 10837–43. doi:10.1021/nn504637y. PMID 25251218.
- Vasyl Skrypnychuk; et al. (February 4, 2015). "Abstract of Enhanced vertical charge transport in a semiconducting P3HT thin film on single layer graphene". Advanced Functional Materials. 25 (5): 664–70. doi:10.1002/adfm.201403418.
- "Discovery could lead to more powerful graphene-based organic electronic devices". KurzweilAI. February 23, 2015. Retrieved February 25, 2017.
- "Graphene promising for future high-efficiency spintronic processors | KurzweilAI". www.kurzweilai.net. April 10, 2015. Retrieved October 12, 2015.
- "What is Graphene?". www.graphene-info.com. Retrieved October 11, 2018.
- "Vorbeck Products RFID". vorbeck.com – Vorbeck Materials. Retrieved October 11, 2018.
- Liu, Ming; Yin; Xiaobo; Ulin-Avila; Erick; Geng; Baisong; Zentgraf; Thomas; Ju; Long; Wang; Feng; Zhang; Xiang (May 8, 2011). "A graphene-based broadband optical modulator". Nature. 474 (7349): 64–67. Bibcode:2011Natur.474...64L. doi:10.1038/nature10067. PMID 21552277. S2CID 2260490.
- Yang, Longzhi; Hu, Ting; Hao, Ran; Qiu, Chen; Xu, Chao; Yu, Hui; Xu, Yang; Jiang, Xiaoqing; Li, Yubo; Yang, Jianyi (2013). "Low-chirp high-extinction-ratio modulator based on graphene–silicon waveguide". Optics Letters. 38 (14): 2512–15. Bibcode:2013OptL...38.2512Y. doi:10.1364/OL.38.002512. PMID 23939097.
- Wang, Junxia; Xu, Yang; Chen, Hongsheng; Zhang, Baile (2012). "Ultraviolet dielectric hyperlens with layered graphene and boron nitride". Journal of Materials Chemistry. 22 (31): 15863. arXiv:1205.4823. Bibcode:2012arXiv1205.4823W. doi:10.1039/C2JM32715E. S2CID 55316208.
- Szondy, David (January 31, 2016). "Graphene optical lens a billionth of a meter thick breaks the diffraction limit". newatlas.com. Retrieved February 18, 2017.
- Scott, Cameron (March 29, 2014). "Contact Lenses with Infrared Vision? Ultra-thin Graphene Opens Up The Possibilities". Singularity Hub. Retrieved April 6, 2014.
- Li, Xinming; Zhu, Miao; Du, Mingde; Lv, Zheng; Zhang, Li; Li, Yuanchang; Yang, Yao; Yang, Tingting; Li, Xiao; Wang, Kunlin; Zhu, Hongwei; Fang, Ying (2016). "High Detectivity Graphene-Silicon Heterojunction Photodetector". Small. 12 (5): 595–601. doi:10.1002/smll.201502336. PMID 26643577.
- Yu, Ting; Wang, Feng; Xu, Yang; Ma, Lingling; Pi, Xiaodong; Yang, Deren (2016). "Graphene Coupled with Silicon Quantum Dots for High-Performance Bulk-Silicon-Based Schottky-Junction Photodetectors". Advanced Materials. 28 (24): 4912–19. doi:10.1002/adma.201506140. PMID 27061073.
- Nair, R. R.; Wu, H. A.; Jayaram, P. N.; Grigorieva, I. V.; Geim, A. K. (2012). "Unimpeded permeation of water through helium-leak-tight graphene-based membranes". Science. 335 (6067): 442–44. arXiv:1112.3488. Bibcode:2012Sci...335..442N. doi:10.1126/science.1211694. PMID 22282806. S2CID 15204080.
- Research Hints at Graphene’s Photovoltaic Potential, Newly observed properties mean graphene could be a highly efficient converter of light to electric power, by Mike Orcutt, MIT. March 1, 2013.
- Zhu, Shou-En; Yuan, Shengjun; Janssen, G. C. A. M. (October 1, 2014). "Optical transmittance of multilayer graphene". EPL. 108 (1): 17007. arXiv:1409.4664. Bibcode:2014EL....10817007Z. doi:10.1209/0295-5075/108/17007. S2CID 73626659.
- Mukhopadhyay, Prithu (2013). Graphite, Graphene and their Polymer Nanocomposites. Boca Raton, Florida: Taylor & Francis Group. pp. 202–13. ISBN 978-1-4398-2779-6.
- "Graphene organic photovoltaics: Flexible material only a few atoms thick may offer cheap solar power". ScienceDaily. July 24, 2010.
Walker, Sohia (August 4, 2010). "Use of graphene photovoltaics as alternate source of energy". Computer Talks.
- inhabitat.com cooperating with ICFO (Institute of Photonic Sciences)(2013-04-03)
- Li, Xinming; Zhu, Hongwei; Wang, Kunlin; Cao, Anyuan; Wei, Jinquan; Li, Chunyan; Jia, Yi; Li, Zhen; Li, Xiao; Wu, Dehai (April 9, 2010). "Graphene-On-Silicon Schottky Junction Solar Cells". Advanced Materials. 22 (25): 2743–48. doi:10.1002/adma.200904383. PMID 20379996.
- Li, Xinming; Xie, Dan; Park, Hyesung; Zeng, Tingying Helen; Wang, Kunlin; Wei, Jinquan; Zhong, Minlin; Wu, Dehai; Kong, Jing; Zhu, Hongwei (April 19, 2013). "Anomalous Behaviors of Graphene Transparent Conductors in Graphene–Silicon Heterojunction Solar Cells". Advanced Energy Materials. 3 (8): 1029–34. doi:10.1002/aenm.201300052.
Li, Xinming; Xie, Dan; Park, Hyesung; Zhu, Miao; Zeng, Tingying Helen; Wang, Kunlin; Wei, Jinquan; Wu, Dehai; Kong, Jing; Zhu, Hongwei (January 3, 2013). "Ion doping of graphene for high-efficiency heterojunction solar cells". Nanoscale. 5 (5): 1945–48. Bibcode:2013Nanos...5.1945L. doi:10.1039/C2NR33795A. PMID 23358527.
- Song, Yi; Li, Xinming; MacKin, Charles; Zhang, Xu; Fang, Wenjing; Palacios, Tomás; Zhu, Hongwei; Kong, Jing (February 16, 2015). "Role of Interfacial Oxide in High-Efficiency Graphene–Silicon Schottky Barrier Solar Cells". Nano Letters. 15 (3): 2104–10. Bibcode:2015NanoL..15.2104S. doi:10.1021/nl505011f. PMID 25685934.
- Li, Xinming; Lv, Zheng; Zhu, Hongwei (September 30, 2015). "Carbon/Silicon Heterojunction Solar Cells: State of the Art and Prospects". Advanced Materials. 27 (42): 6549–74. doi:10.1002/adma.201502999. PMID 26422457.
- "Graphene-based solar cell hits record 15.6 percent efficiency". Gizmag.com. January 15, 2014. Retrieved January 23, 2014.
Wang, J. T. W.; Ball, J. M.; Barea, E. M.; Abate, A.; Alexander-Webber, J. A.; Huang, J.; Saliba, M.; Mora-Sero, I. N.; Bisquert, J.; Snaith, H. J.; Nicolas, R. J. (2013). "Low-temperature processed electron collection layers of Graphene/TiO2 nanocomposites in thin film perovskite solar cells". Nano Letters. 14 (2): 724–30. Bibcode:2014NanoL..14..724W. doi:10.1021/nl403997a. PMID 24341922.
- Jeffrey, Colin (September 11, 2015). "High-efficiency, semi-transparent perovskite/graphene solar cells created at low cost". www.gizmag.com. Retrieved October 13, 2015.
- "Protons found to pass through graphene, raising hopes for efficient fuel cells". KurzweilAI. December 1, 2014. Retrieved February 25, 2017.
- Holmes, Stuart M.; Balakrishnan, Prabhuraj; Kalangi, Vasu. S.; Zhang, Xiang; Lozada-Hidalgo, Marcelo; Ajayan, Pulickel M.; Nair, Rahul R. (November 2016). "2D Crystals Significantly Enhance the Performance of a Working Fuel Cell" (PDF). Advanced Energy Materials. 7 (5): 1601216. doi:10.1002/aenm.201601216.
- Hu, S.; Lozada-Hidalgo, M.; Wang, F. C.; Mishchenko, A.; Schedin, F.; Nair, R. R.; Hill, E. W.; Boukhvalov, D. W.; Katsnelson, M. I.; Dryfe, R. A. W.; Grigorieva, I. V.; Wu, H. A.; Geim, A. K. (November 26, 2014). "Proton transport through one-atom-thick crystals". Nature. 516 (7530): 227–30. arXiv:1410.8724. Bibcode:2014Natur.516..227H. doi:10.1038/nature14015. PMID 25470058. S2CID 4455321.
- "Imperfect graphene may lead to fast-charging batteries for vehicles". March 17, 2015. Retrieved February 26, 2017. Cite journal requires
- Achtyl, Jennifer L.; Unocic, Raymond R.; Xu, Lijun; Cai, Yu; Raju, Muralikrishna; Zhang, Weiwei; Sacci, Robert L.; Vlassiouk, Ivan V.; Fulvio, Pasquale F.; Ganesh, Panchapakesan; Wesolowski, David J.; Dai, Sheng; Duin, Adri C. T. van; Neurock, Matthew; Geiger, Franz M. (March 17, 2015). "Aqueous proton transfer across single-layer graphene". Nature Communications. 6: 6539. arXiv:1411.1034. Bibcode:2015NatCo...6.6539A. doi:10.1038/ncomms7539. PMC 4382684. PMID 25781149.
- Singh, Chanderpratap; S., Nikhil; Jana, Anwesha; Mishra, Ashish Kumar; Paul, Amit (2016). "Proton conduction through oxygen functionalized few-layer graphene". Chemical Communications. 52 (85): 12661–64. doi:10.1039/c6cc07231c. PMID 27722614.
- "Hot stuff". The Economist. August 1, 2015. ISSN 0013-0613. Retrieved October 11, 2015.
- Wood, Chris (June 2, 2015). "Coating condensers with graphene could increase power plant efficiency". www.gizmag.com. Retrieved October 14, 2015.
- Stoller, Meryl D.; Park, Sungjin; Zhu, Yanwu; An, Jinho; Ruoff, Rodney S. (2008). "Graphene-Based Ultracapacitors" (PDF). Nano Lett. 8 (10): 3498–502. Bibcode:2008NanoL...8.3498S. doi:10.1021/nl802558y. PMID 18788793. Archived from the original (PDF) on March 20, 2013.
- Malasarn, Davin (February 19, 2013). "UCLA researchers develop new technique to scale up production of graphene micro-supercapacitors / UCLA Newsroom". Newsroom.ucla.edu.
- Williams, Mike (January 14, 2015). "Laser-induced graphene "super" for electronics". R&D Magazine. Retrieved February 20, 2015.
- "Flexible 3D graphene supercapacitors may power portables and wearables". Kurzweil Accelerating Intelligence. February 9, 2015. Retrieved February 25, 2017.
- Mason, Shaun (April 1, 2015). "Quick-charging hybrid supercapacitors". R&D. Retrieved April 1, 2015.
- Maher F. El-Kady; Melanie Ihns; Mengping Li; Jee Youn Hwang; Mir F. Mousavi; Lindsay Chaney; Andrew T. Lech; Richard B. Kaner (March 4, 2015). "Engineering three-dimensional hybrid supercapacitors and microsupercapacitors for high-performance integrated energy storage". PNAS. 112 (14): 4233–38. Bibcode:2015PNAS..112.4233E. doi:10.1073/pnas.1420398112. PMC 4394298. PMID 25831542. Retrieved February 26, 2017.
- "Wearables and electric vehicles may get boost from boron-infused graphene | KurzweilAI". www.kurzweilai.net. May 19, 2015. Retrieved October 14, 2015.
- Peng, Zhiwei; Ye, Ruquan; Mann, Jason A.; Zakhidov, Dante; Li, Yilun; Smalley, Preston R.; Lin, Jian; Tour, James M. (May 19, 2015). "Flexible Boron-Doped Laser-Induced Graphene Microsupercapacitors". ACS Nano. 9 (6): 5868–75. doi:10.1021/acsnano.5b00436. PMID 25978090.
- Johnson, Dexter (March 21, 2012). "Graphene-Silicon Anodes for Li-ion Batteries Go Commercial – IEEE Spectrum". Spectrum.ieee.org.
"XGS presents new silicon-graphene anode materials for lithium-ion batteries". Phys.org. Retrieved February 26, 2014.
- David, L.; Bhandavat, R.; Kulkarni, G.; Pahwa, S.; Zhong, Z.; Singh, G. (2013). "Synthesis of Graphene Films by Rapid Heating and Quenching at Ambient Pressures and Their Electrochemical Characterization". ACS Applied Materials & Interfaces. 5 (3): 546–52. doi:10.1021/am301782h. PMID 23268553.
Radhakrishnan, Gouri; Cardema, Joanna D.; Adams, Paul M.; Kim, Hyun I.; Foran, Brendan (2012). "Fabrication and Electrochemical Characterization of Single and Multi-Layer Graphene Anodes for Lithium-Ion Batteries". Journal of the Electrochemical Society. 159 (6): A752–61. doi:10.1149/2.052206jes.
- Yao, F.; Güneş, F.; Ta, H. Q.; Lee, S. M.; Chae, S. J.; Sheem, K. Y.; Cojocaru, C. S.; Xie, S. S.; Lee, Y. H. (2012). "Diffusion Mechanism of Lithium Ion through Basal Plane of Layered Graphene". Journal of the American Chemical Society. 134 (20): 8646–54. CiteSeerX 10.1.1.400.2791. doi:10.1021/ja301586m. PMID 22545779.
- Johnson, Dexter (January 17, 2013). "Faster and Cheaper Process for Graphene in Li-ion Batteries". Spectrum.ieee.org – IEEE Spectrum.
- 5 Ways Graphene Will Change Gadgets Forever, Laptop, 14 April 2014, Michael Andronico
- "Charged holes in graphene increase energy storage capacity | KurzweilAI". www.kurzweilai.net. April 23, 2015. Retrieved October 14, 2015.
- Narayanan, R.; Yamada, H.; Karakaya, M.; Podila, R.; Rao, A. M.; Bandaru, P. R. (April 2, 2015). "Modulation of the Electrostatic and Quantum Capacitances of Few Layered Graphenes through Plasma Processing". Nano Letters. 15 (5): 3067–72. Bibcode:2015NanoL..15.3067N. doi:10.1021/acs.nanolett.5b00055. PMID 25826121.
- Black, Douglas (December 6, 2016). "Huawei boost batteries with graphene-reinforced Li-ion technology". Notebookcheck. Retrieved July 25, 2020.
- "Huawei Achieves Major Breakthrough in Graphene-Assisted High Temperature Li-ion Batteries - huawei press center". huawei. December 6, 2016. Retrieved July 25, 2020.
- Lynch, Gerald (December 6, 2016). "Huawei's next battery breakthrough is a graphene-powered gain". TechRadar. Retrieved July 25, 2020.
- "Graphene Biosensors". Graphenea. Retrieved August 9, 2017.
- Xu, Yang; Guo, Zhendong; Chen, Huabin; Yuan, You; Lou, Jiechao; Lin, Xiao; Gao, Haiyuan; Chen, Hongsheng; Yu, Bin (2011). "In-plane and tunneling pressure sensors based on graphene/hexagonal boron nitride heterostructures". Applied Physics Letters. 99 (13): 133109. Bibcode:2011ApPhL..99m3109X. doi:10.1063/1.3643899.
- Coxworth, Ben (December 9, 2016). "Silly Putty smartens up, with a dash of graphene". newatlas.com. Retrieved April 30, 2017.
- Yan, Sheping; Xu, Yang; Jin, Zhonghe; Wang, Yuelin (2010). "Quantum Squeezing Effects of Monolayer Graphene NEMS". AIP Conference Proceedings: 785–86. doi:10.1063/1.3666611.
- Dan, Yaping; Lu, Ye; Kybert, Nicholas J.; Luo, Zhengtang; Johnson, A. T. Charlie (April 2009). "Intrinsic Response of Graphene Vapor Sensors". Nano Letters. 9 (4): 1472–75. arXiv:0811.3091. Bibcode:2009NanoL...9.1472D. doi:10.1021/nl8033637. PMID 19267449. S2CID 23190568.
- Schedin, F.; Geim, A. K.; Morozov, S. V.; Hill, E. W.; Blake, P.; Katsnelson, M. I.; Novoselov, K. S. (2007). "Detection of individual gas molecules adsorbed on graphene". Nature Materials. 6 (9): 652–55. arXiv:cond-mat/0610809. Bibcode:2007NatMa...6..652S. doi:10.1038/nmat1967. PMID 17660825. S2CID 3518448.
- "Straintronics: Stanford engineers create piezoelectric graphene". Stanford University. April 3, 2012.
Ong, M.; Reed, Evan J. (2012). "Engineered Piezoelectricity in Graphene". ACS Nano. 6 (2): 1387–94. doi:10.1021/nn204198g. PMID 22196055.
- Li, Xinming; Yang, Tingting; Yang, Yao; Zhu, Jia; Li, Li; Alam, Fakhr E.; Li, Xiao; Wang, Kunlin; Cheng, Huanyu; Lin, Cheng-Te; Fang, Ying; Zhu, Hongwei (2016). "Large-Area Ultrathin Graphene Films by Single-Step Marangoni Self-Assembly for Highly Sensitive Strain Sensing Application". Advanced Functional Materials. 26 (9): 1322–29. doi:10.1002/adfm.201504717.
- Boland, C. S.; Khan, U.; Backes, C.; o’Neill, A.; McCauley, J.; Duane, S.; Shanker, R.; Liu, Y.; Jurewicz, I.; Dalton, A. B.; Coleman, J. N. (2014). "Sensitive, High-Strain, High-Rate Bodily Motion Sensors Based on Graphene–Rubber Composites". ACS Nano. 8 (9): 8819–30. doi:10.1021/nn503454h. PMID 25100211.
- Sedgemore, Francis (June 29, 2015). "Bosch announces breakthrough in graphene sensor technology". R&D. Retrieved September 26, 2015.
- Cohen-Tanugi, David; Grossman, Jeffrey C. (2012). "Water Desalination across Nanoporous Graphene". Nano Letters. 12 (7): 3602–08. Bibcode:2012NanoL..12.3602C. doi:10.1021/nl3012853. PMID 22668008.
- Choi, Kyoungjun; et al. (2015). "Reduced Water Vapor Transmission Rate of Graphene Gas Barrier Films for Flexible Organic Field-Effect Transistors". ACS Nano. 9 (6): 5818–24. doi:10.1021/acsnano.5b01161. PMID 25988910.
- Sagade, Abhay; et al. (2017). "Graphene-based nanolaminates as ultra-high permeation barriers". NPJ 2D Materials and Applications. 1: 35. doi:10.1038/s41699-017-0037-z.
- Zeng, S.; et al. (2015). "Graphene-gold metasurface architectures for ultrasensitive plasmonic biosensing" (PDF). Advanced Materials. 27 (40): 1–7. doi:10.1002/adma.201501754. PMID 26349431.
- Chen, J.; Badioli, M.; Alonso-González, P.; Thongrattanasiri, S.; Huth, F.; Osmond, J.; Spasenović, M.; Centeno, A.; Pesquera, A.; Godignon, P.; Zurutuza Elorza, A.; Camara, N.; De Abajo, F. J. G. A.; Hillenbrand, R.; Koppens, F. H. L. (2012). "Optical nano-imaging of gate-tunable graphene plasmons". Nature. 487 (7405): 77–81. arXiv:1202.4996. Bibcode:2012Natur.487...77C. doi:10.1038/nature11254. PMID 22722861. S2CID 4431470.
- Fei, Z.; Rodin, A. S.; Andreev, G. O.; Bao, W.; McLeod, A. S.; Wagner, M.; Zhang, L. M.; Zhao, Z.; Thiemens, M.; Dominguez, G.; Fogler, M. M.; Neto, A. H. C.; Lau, C. N.; Keilmann, F.; Basov, D. N. (2012). "Gate-tuning of graphene plasmons revealed by infrared nano-imaging". Nature. 487 (7405): 82–85. arXiv:1202.4993. Bibcode:2012Natur.487...82F. doi:10.1038/nature11253. PMID 22722866. S2CID 4348703.
- Yan, H.; Low, T.; Zhu, W.; Wu, Y.; Freitag, M.; Li, X.; Guinea, F.; Avouris, P.; Xia, F. (2013). "Damping pathways of mid-infrared plasmons in graphene nanostructures". Nature Photonics. 7 (5): 394–99. arXiv:1209.1984. Bibcode:2013NaPho...7..394Y. doi:10.1038/nphoton.2013.57.
- Low, T.; Avouris, P. (2014). "Graphene Plasmonics for Terahertz to Mid-Infrared Applications". ACS Nano. 8 (2): 1086–101. arXiv:1403.2799. Bibcode:2014arXiv1403.2799L. doi:10.1021/nn406627u. PMID 24484181. S2CID 8151572.
- Rodrigo, D.; Limaj, O.; Janner, D.; Etezadi, D.; Garcia de Abajo, F.J.; Pruneri, V.; Altug, H. (2015). "Mid-infrared plasmonic biosensing with graphene". Science. 349 (6244): 165–68. arXiv:1506.06800. Bibcode:2015Sci...349..165R. doi:10.1126/science.aab2051. PMID 26160941. S2CID 206637774.
- Graphene proves a long-lasting lubricant, Phys.org, 14 October 2014, Jared Sagoff
- "Graphene found to efficiently absorb radio waves". KurzweilAI. Retrieved February 26, 2014.
- Wu, B.; Tuncer, H. M.; Naeem, M.; Yang, B.; Cole, M. T.; Milne, W. I.; Hao, Y. (2014). "Experimental demonstration of a transparent graphene millimetre wave absorber with 28% fractional bandwidth at 140 GHz". Scientific Reports. 4: 4130. Bibcode:2014NatSR...4E4130W. doi:10.1038/srep04130. PMC 3928574. PMID 24549254.
- Ekiz, O.O.; Urel, M; et al. (2011). "Reversible Electrical Reduction and Oxidation of Graphene Oxide". ACS Nano. 5 (4): 2475–82. doi:10.1021/nn1014215. hdl:11693/13319. PMID 21391707. Cite uses deprecated parameter
Ekiz, O.O.; Urel, M; et al. (2011). "Supporting information for Reversible Electrical Reduction and Oxidation of Graphene Oxide". ACS Nano. 5 (4): 2475–82. doi:10.1021/nn1014215. hdl:11693/13319. PMID 21391707. Cite uses deprecated parameter
- Dodson, Brian (February 3, 2014). "Graphene-based nano-antennas may enable cooperating smart dust swarms". Gizmag.com. Retrieved April 6, 2014.
- "Optical antennas trap and control light with the help of graphene". May 23, 2014.
- Ren, Xingang; Sha, Wei E. I.; Choy, Wallace C. H. (2013). "Tuning optical responses of metallic dipole nanoantenna using graphene". Optics Express. 21 (26): 31824–29. Bibcode:2013OExpr..2131824R. doi:10.1364/OE.21.031824. hdl:10722/202884. PMID 24514777.
- "World's first graphene speaker already superior to Sennheiser MX400". Gizmag.com. April 16, 2014. Retrieved April 24, 2014., full paper on arxiv.org
- Qin Zhoua; Jinglin Zhenga; Seita Onishi; M. F. Crommiea; Alex K. Zettl (July 21, 2015). "Graphene electrostatic microphone and ultrasonic radio" (PDF). PNAS. 112 (29): 8942–46. Bibcode:2015PNAS..112.8942Z. doi:10.1073/pnas.1505800112. PMC 4517232. PMID 26150483.
- Yu, W.; Xie, H.; Wang, X.; Wang, X. (2011). "Significant thermal conductivity enhancement for nanofluids containing graphene nanosheets". Physics Letters A. 375 (10): 1323–28. Bibcode:2011PhLA..375.1323Y. doi:10.1016/j.physleta.2011.01.040.
- Nair, R. R.; Blake, P.; Grigorenko, A. N.; Novoselov, K. S.; Booth, T. J.; Stauber, T.; Peres, N. M. R.; Geim, A. K. (2008). "Fine Structure Constant Defines Visual Transparency of Graphene". Science. 320 (5881): 1308. arXiv:0803.3718. Bibcode:2008Sci...320.1308N. doi:10.1126/science.1156965. PMID 18388259.
- Eigler, S. (2009). "A new parameter based on graphene for characterizing transparent, conductive materials". Carbon. 47 (12): 2936–39. doi:10.1016/j.carbon.2009.06.047.
- Liang, Qizhen; Yao, Xuxia; Wang, Wei; Liu, Yan; Wong, Ching Ping (2011). "A Three-Dimensional Vertically Aligned Functionalized Multilayer Graphene Architecture: An Approach for Graphene-Based Thermal Interfacial Materials". ACS Nano. 5 (3): 2392–2401. doi:10.1021/nn200181e. PMID 21384860.
- Amini, Shaahin; Garay, Javier; Liu, Guanxiong; Balandin, Alexander A.; Abbaschian, Reza (2010). "Growth of Large-Area Graphene Films from Metal-Carbon Melts". Journal of Applied Physics. 108 (9): 094321–. arXiv:1011.4081. Bibcode:2010JAP...108i4321A. doi:10.1063/1.3498815. S2CID 17739020.
- Nealon, Sean (March 12, 2014). "Graphene-copper sandwich may improve, shrink electronics". Rdmag.com. Retrieved April 6, 2014.
- "Using graphene-based film for efficient cooling of electronics | KurzweilAI". www.kurzweilai.net. July 13, 2015. Retrieved September 26, 2015.
- Galatzer-Levy, Jeanne (June 17, 2015). "Graphene heat-transfer riddle unraveled". R&D. Retrieved September 26, 2015.
- Lalwani, G; Henslee, A. M.; Farshid, B; Lin, L; Kasper, F. K.; Qin, Y. X.; Mikos, A. G.; Sitharaman, B (2013). "Two-dimensional nanostructure-reinforced biodegradable polymeric nanocomposites for bone tissue engineering". Biomacromolecules. 14 (3): 900–09. doi:10.1021/bm301995s. PMC 3601907. PMID 23405887.
- Research unlocks potential of super-compound, Phys.org, 22 October 2014, David Stacey
- Williams, Mike (October 21, 2015). "Cobalt atoms on graphene a powerful combo". Retrieved April 29, 2017.
- Fei, Huilong; Dong, Juncai; Arellano-Jiménez, M. Josefina; Ye, Gonglan; Dong Kim, Nam; Samuel, Errol L.G.; Peng, Zhiwei; Zhu, Zhuan; Qin, Fan; Bao, Jiming; Yacaman, Miguel Jose; Ajayan, Pulickel M.; Chen, Dongliang; Tour, James M. (October 21, 2015). "Atomic cobalt on nitrogen-doped graphene for hydrogen generation". Nature Communications. 6 (1): 8668. Bibcode:2015NatCo...6.8668F. doi:10.1038/ncomms9668. PMC 4639894. PMID 26487368.
- Kramm, Ulrike I.; Herrmann-Geppert, Iris; Behrends, Jan; Lips, Klaus; Fiechter, Sebastian; Bogdanoff, Peter (January 4, 2016). "On an Easy Way To Prepare Metal–Nitrogen Doped Carbon with Exclusive Presence of MeN4-type Sites Active for the ORR". Journal of the American Chemical Society. 138 (2): 635–40. doi:10.1021/jacs.5b11015. PMID 26651534.
- Coxworth, Ben (January 27, 2016). "A pinch of graphene could keep airplane wings ice-free". newatlas.com. Retrieved February 18, 2017.