Graphene is a single planar sheet of sp²-bonded carbon atoms that are densely packed in a honeycomb crystal lattice. It can also be viewed as an atomic-scale chicken wire made of carbon atoms and their bonds. The carbon-carbon bond length in graphene is approximately 1.42 Å. From a physicist's point of view, graphene is the basic structural element for all other graphitic materials including graphite, carbon nanotubes and fullerenes. For a chemist, graphene is an infinitely large aromatic molecule, an extension of a family of flat polycyclic aromatic hydrocarbons called graphenes. Notice: For a full understanding of this article, it is important to read and understand the article on orbital hybridization. ... For other uses, see Carbon (disambiguation). ... Chicken wire Chicken wire, or poultry netting, is a mesh of wire, generally used for making fences. ... For other uses, see Graphite (disambiguation). ... An electronic device known as a diode can be formed by joining two nanoscale carbon tubes with different electronic properties. ... Buckminsterfullerene (C60) Fullerenes are molecules composed entirely of carbon, taking the form of a hollow sphere, ellipsoid, or tube. ... Aromaticity is a chemical property in which a conjugated ring of unsaturated bonds, lone pairs, or empty orbitals exhibit a stabilization stronger than would be expected by the stabilization of conjugation alone. ... An aromatic hydrocarbon (abbreviated as AH), or arene is a hydrocarbon, the molecular structure of which incorporates one or more planar sets of six carbon atoms that are connected by delocalised electrons numbering the same as if they consisted of alternating single and double covalent bonds. ...

Graphene is an atomic-scale chicken wire made of carbon atoms

Chicken wire The term chicken wire in chemistry is used in different contexts. ...

Description

Perfect graphenes consist exclusively of hexagonal cells; pentagonal and heptagonal cells constitute defects. If an isolated pentagonal cell is present, then the plane warps into a cone shape; insertion of 12 pentagons would create a fullerene. Likewise, insertion of an isolated heptagon causes the sheet to become saddle-shaped. Controlled addition of pentagons and heptagons would allow a wide variety of complex shapes to be made, for instance carbon NanoBuds. Single walled carbon nanotubes may be considered to be graphene cylinders; some have a hemispherical graphene cap (that includes 6 pentagons) at each end. Look up pentagon in Wiktionary, the free dictionary. ... This article is about the geometric object, for other uses see Cone. ... The Icosahedral Fullerene C540 C60 and C-60 redirect here. ... In geometry, a heptagon is a polygon with seven sides and seven angles. ... Computer models of several stable NanoBud structures In nanotechnology, carbon NanoBuds are a newly discovered material combining two previously discovered allotropes of carbon: carbon nanotubes and fullerenes. ... 3D model of three types of single-walled carbon nanotubes. ...

The IUPAC compendium of technology states: "previously, descriptions such as graphite layers, carbon layers, or carbon sheets have been used for the term graphene…it is not correct to use for a single layer a term which includes the term graphite, which would imply a three-dimensional structure. The term graphene should be used only when the reactions, structural relations or other properties of individual layers are discussed". In this regard, graphene has been referred to as an infinite alternant (only six-member carbon ring) polycyclic aromatic hydrocarbon. The onset of graphene properties, as compared to those of a polycyclic aromatic hydrocarbon are not known. PAHs of 60, 78, and 120 carbon atoms have UV absorbance spectra that show a discrete PAH electronic structure, but a PAH of 222 carbon atoms has Raman bands similar to those in graphite. The International Union of Pure and Applied Chemistry (IUPAC) is an international non-governmental organization devoted to the advancement of chemistry. ... For other uses, see Graphite (disambiguation). ... An illustration of typical polycyclic aromatic hydrocarbons. ... An illustration of typical polycyclic aromatic hydrocarbons. ... For other uses, see Graphite (disambiguation). ...

Occurrence

Physicists from the University of Manchester who first found and studied graphene (rather than PAH) in 2004, defined it in Science^[1] as: Affiliations: Russell Group, EUA, N8 Group, NWUA, Worldwide Universities Network (WUN), Association of Commonwealth Universities Website: http://www. ... Science is the academic journal of the American Association for the Advancement of Science and is considered one of the worlds most prestigious scientific journals. ...

Graphene is the name given to a single layer of carbon atoms densely packed into a benzene-ring structure, and is widely used to describe properties of many carbon-based materials, including graphite, large fullerenes, nanotubes, etc. (e.g., carbon nanotubes are usually thought of as graphene sheets rolled up into nanometer-sized cylinders). Planar graphene itself has been presumed not to exist in the free state, being unstable with respect to the formation of curved structures such as soot, fullerenes, and nanotubes. For other uses, see Graphite (disambiguation). ... Buckminsterfullerene (C60) Fullerenes are molecules composed entirely of carbon, taking the form of a hollow sphere, ellipsoid, or tube. ... An electronic device known as a diode can be formed by joining two nanoscale carbon tubes with different electronic properties. ... A nanometre (American spelling: nanometer) is 1. ... A right circular cylinder An elliptic cylinder In mathematics, a cylinder is a quadric surface, with the following equation in Cartesian coordinates: This equation is for an elliptic cylinder, a generalization of the ordinary, circular cylinder (a = b). ... Soot, also called lampblack, Pigment Black 7, carbon black or black carbon, is a dark powdery deposit of unburned fuel residues, usually composed mainly of amorphous carbon, that accumulates in chimneys, automobile mufflers and other surfaces exposed to smoke—especially from the combustion of carbon-rich organic fuels in the...

The British researchers obtained relatively large graphene sheets (eventually, up to 100 microns in size and visible through a magnifying glass) by mechanical exfoliation (repeated peeling) of 3D graphite crystals; their motivation was allegedly to study the electrical properties of thin graphite films and, as purely two-dimensional crystals were unknown before and presumed not to exist, their discovery of individual planes of graphite was presumably accidental. Both theory and experiment previously suggested that perfect 2D structures could not exist in the free state. It is believed that intrinsic microscopic roughening on the scale of 1 nm could be important for the stability of 2D crystals.^[2] The space we live in is three-dimensional space. ... 2D may refer to: Look up 2d in Wiktionary, the free dictionary. ...

Similar work is ongoing at many universities and the results obtained by the Manchester group in their PNAS paper "Two-dimensional atomic crystals" have been confirmed by several groups.^[3] For an example of a sample on the order of a monolayer, see figure 1. The Proceedings of the National Academy of Sciences (USA), mostly commonly referred to as PNAS, is the official publication of the National Academy of Sciences of the United States of America. ...

Graphene sheets in solid form (e.g. density > 1g/cc) usually show evidence in diffraction for graphite's 0.34 nm (002) layering. This is true even of some single-walled carbon nanostructures^[4]. However unlayered graphene with only (hk0) rings has been found in the core of presolar graphite onions^[5]. Transmission electron microscope studies show faceting at defects in flat graphene sheets^[6], and suggest a possible role in this unlayered-graphene for two-dimensional dendritic crystallization from a melt^[7]. For other uses, see Graphite (disambiguation). ... Presolar grains are tiny crystalline grains found in the fine-grained matrix of primitive meteorites, and are assumed to be older than the solar system. ... Transmission electron microscopy (TEM) is an imaging technique whereby a beam of electrons is focused onto a specimen causing an enlarged version to appear on a fluorescent screen or layer of photographic film (see electron microscope), or can be detected by a CCD camera. ... This rock was used a pavement around swimming pool area in Kona A crystal dendrite is a crystal that develops with a typical multi-branching tree-like form. ...

Properties

Electronic Properties

Figure 1. This image was captured using a Digital Multimode AFM (atomic force microscope). Notice the step from the substrate at zero height to a graphene flake about 8 angstroms high, which is on the order of a monolayer. ^[8]

While electron transport in most condensed matter systems are accurately described by the non-relativistic Schrödinger equation, graphene is quite different from most conventional three-dimensional materials. Intrinsic graphene is a semi-metal or zero-gap semiconductor. The E-k relation is linear for low energies near the six corners of the two-dimensional hexagonal Brillouin zone, leading to zero effective mass for electrons and holes. ^[9] Due to this linear “dispersion” relation at low energies, electrons and holes near these six points behave like relativistic particles described by the Dirac equation for spin 1/2 particles. ^[10] Hence, the electrons and holes are called Dirac fermions, and the six corners of the Brillouin zone are called the Dirac points.^[9] The equation describing the E-k relation is ; where v_f, the Fermi velocity, is approximately 10⁶m / s.^[10] Image File history File linksMetadata Graphene. ... Image File history File linksMetadata Graphene. ... Topographic scan of a glass surface The atomic force microscope (AFM) is a very high-resolution type of scanning probe microscope, with demonstrated resolution of fractions of a nanometer, more than 1000 times better than the optical diffraction limit. ... It has been suggested that Wafer prober be merged into this article or section. ... An angstrom, angström, or Ã¥ngström (symbol Ã…) is a unit of length. ... A monolayer is a single, closely packed layer of atoms or molecules [1]. A Langmuir monolayer is a one-molecule thick insoluble layer of an organic material spread onto an aqueous subphase. ... For a non-technical introduction to the topic, please see Introduction to quantum mechanics. ... Together with the metals and nonmetals, the metalloids (in Greek metallon = metal and eidos = sort - also called semimetals) form one of the three categories of chemical elements as classified by ionization and bonding properties. ... A semiconductor is a solid whose electrical conductivity is in between that of a conductor and that of an insulator, and can be controlled over a wide range, either permanently or dynamically. ... In mathematics and solid state physics, the first Brillouin zone is the primitive cell in the reciprocal lattice in momentum space. ... In solid state physics, a particles effective mass is the mass it seems to carry in the semiclassical model of transport in a crystal. ... Two-dimensional analogy of space-time curvature described in General Relativity. ... In physics, the Dirac equation is a relativistic quantum mechanical wave equation formulated by British physicist Paul Dirac in 1928 and provides a description of elementary spin-½ particles, such as electrons, consistent with both the principles of quantum mechanics and the theory of special relativity. ... Fermions, named after Enrico Fermi, are particles which form totally-antisymmetric composite quantum states. ... In physics, Fermi momentum is the momentum of fermions at the Fermi surface. ...

Optical properies

Graphene's unique electronic properties produce an unexpectedly high opacity for an atomic monolayer, with a startlingly simple value: it absorbs πα = 2.3% of white light, where α is the fine-structure constant.^[11] This has been confirmed experimentally, but the measurement is not precise enough to improve on other techniques for determining the fine-structure constant.^[12] For other uses, see Light (disambiguation). ... The fine-structure constant or Sommerfeld fine-structure constant, usually denoted , is the fundamental physical constant characterizing the strength of the electromagnetic interaction. ...

Electronic Transport

Experimental results from transport measurements show that graphene has a remarkably high mobility at room temperature, with reported values in excess of 15000cm²V ^{− 1}s ^{− 1}. ^[13] These high mobilities are independent of temperature between 10 and 100K ^[14], which implies that the dominant scattering mechanism is defect scattering. Additionally, the symmetry of the experimentally measured conductance indicates that the mobilities for holes and electrons should be nearly the same.^[9] Recent results suggest that mobilities greater than 200,000cm²V ^{− 1}s ^{− 1} are possible if extrinsic disorder can be eliminated.^[15] This does not adequately cite its references or sources. ...

Despite the zero carrier density near the Dirac points, graphene exhibits a minimum conductivity on the order of 4e² / h. The origin of this minimum conductivity is still unclear; however, rippling of the graphene sheet or ionized impurities in the SiO₂ substrate may lead to local puddles of carriers that allow conduction.^[9] Several theories suggest that the minimum conductivity should be 4e² / hπ; however, most measurements are very close to 4e² / h.^[13] Not to be confused with electrical conductance, a measure of an objects or circuits ability to conduct an electric current between two points, which is dependent on the electrical conductivity and the geometric dimensions of the conducting object. ...

Recent experimental data suggests that doping does not influence the carrier mobility in graphene. The results show that some gaseous species are acceptors, some are donors, and the initial undoped state of a graphene structure can be recovered by gently heating the graphene in vacuum. Even for chemical dopant concentrations in excess of 10¹²cm ^{− 2} there is no observable change in the carrier mobility.^[16]

Magnetic Effects

Besides the high mobility and minimum conductivity, graphene shows very interesting behavior in the presence of a magnetic field. Graphene displays an anomalous quantum Hall effect with the sequence shifted by 1 / 2 with respect to the standard sequence. Thus, the Hall conductivity is , where N is the Landau level index and the double valley and double spin degeneracies give the factor of 4.^[13] This remarkable behavior can even be measured at room temperature.^[14] Bilayer graphene also shows the quantum Hall effect, but with the standard sequence where . Interestingly, the first plateau at N = 0 is absent, indicating that bilayer graphene stays metallic at the neutrality point.^[13] The quantum Hall effect is a quantum-mechanical version of the Hall effect, observed in two-dimensional electron systems subjected to low temperatures and strong magnetic fields, in which the Hall conductance takes on the quantized values where is the elementary charge and is Plancks constant. ...

Unlike normal metals, the longitudinal resistance of graphene shows maxima rather than minima for integral values of the Landau filling factor in measurements of the Shubnikov-de Haas oscillations, which show a phase shift of π, known as Berry’s phase.^[9][14] The Berry’s phase arises due to the zero effective carrier mass near the Dirac points.^[17] Study of the temperature dependence of the Shubnikov-de Haas oscillations in graphene reveals that the carriers have a non-zero cyclotron mass, despite their zero effective mass from the E-k relation.^[14] // An oscillation in the conductivity of a material that occurs at low temperatures in the presence of very intense, time varying magnetic fields, the Shubnikov-de Haas effect is a macroscopic manifestation of the inherent quantum mechanical nature of matter. ...

Graphene oxide

By oxidising and chemically processing graphene, and then floating them in water, the graphene flakes form a single sheet and bond very powerfully. These sheets have a measured tensile modulus of 32 GPa.^[18] The initials GPA can refer, among other things, to Grade Point Average; see Grade (education) Guinness Peat Aviation General Practice Australia, a private, independent medical accreditation society Greyhound Pets of America This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...

Chemical modification

Soluble fragments of graphene can be prepared in the laboratory^[19] through chemical modification of graphite. First, microcrystalline graphite is treated with a strongly acidic mixture of sulfuric acid and nitric acid. A series of steps involving oxidation and exfoliation result in small graphene plates with carboxyl groups at their edges. These are converted to acid chloride groups by treatment with thionyl chloride; next, they are converted to the corresponding graphene amide via treatment with octadecylamine. The resulting material (circular graphene layers of 5.3 angstrom thickness) is soluble in tetrahydrofuran, tetrachloromethane, and dichloroethane. R-phrases S-phrases , , , Flash point Non-flammable Related Compounds Related strong acids Selenic acid Hydrochloric acid Nitric acid Related compounds Hydrogen sulfide Sulfurous acid Peroxymonosulfuric acid Sulfur trioxide Oleum Supplementary data page Structure and properties n, εr, etc. ... The chemical compound nitric acid (HNO3), also known as aqua fortis and spirit of nitre, is an aqueous solution of hydrogen nitrate (anhydrous nitric acid). ... A carboxyl or carboxylic group is a functional group consisting of a carbon atom and an oxygen atom doubly bonded to each other. ... In organic chemistry, an acid chloride (or acyl chloride) is very reactive derivative of a carboxylic acid. ... R-phrases , , , S-phrases , , , Flash point non flammable Supplementary data page Structure and properties n, εr, etc. ... Amide functional group Amides possess a conjugated system spread over the O, C and N atoms, consisting of molecular orbitals occupied by delocalized electrons. ... An angstrom, angström, or ångström (symbol Å) is a unit of length. ... For other uses of THF, see THF (disambiguation) Tetrahydrofuran is a heterocyclic organic compound. ... Carbon tetrachloride CCl4 is a synthetic chemical compound formerly widely used in fire extinguishers and refrigeration, but now largely abandoned due to its toxicity. ... Dichloroethane can refer to: 1,2-Dichloroethane (ethylene dichloride) Ethylidene dichloride (1,1-dichloroethane) Also check out haloalkane. ...

Thermal properties

The near-room temperature thermal conductivity of graphene was recently measured to be between (4.84±0.44) ×10³ to (5.30±0.48) ×10³ Wm⁻¹K⁻¹. These measurements, made by a non-contact optical technique, are in excess of those measured for carbon nanotubes or diamond. It can be shown by using the Wiedemann-Franz law, that the thermal conduction is phonon-dominated.^[20] However for a gated graphene strip, an applied gate bias causing a Fermi Energy shift much larger than k_BT can cause the electronic contribution to increase and dominate over the phonon contribution at low temperatures.^[21] K value redirects here. ... In physics, the Wiedemann-Franz law states that the ratio of the thermal conductivity (K) to the electrical conductivity (σ) of a metal is proportional to the temperature (T). ... The Fermi energy is a concept in quantum mechanics referring to the energy of the highest occupied quantum state in a system of fermions at absolute zero temperature. ... Normal modes of vibration progression through a crystal. ...

Potential for this high conductivity can be seen by considering graphite, a 3D version of graphene that has basal plane thermal conductivity of over a 1000 W/mK (comparable to diamond). In graphite, the c-axis (out of plane) thermal conductivity is over a factor of ~100 smaller due to the weak binding forces between basal planes as well as the larger lattice spacing.^[22] In addition, the ballistic thermal conductance of a graphene is shown to give the lower limit of the ballistic thermal conductances, per unit circumference, length of carbon nanotubes.^[23] For other uses, see Graphite (disambiguation). ... This article is about the mineral. ... For other uses, see Graphite (disambiguation). ... K value redirects here. ... In physics, thermal conductivity, λ, is the quantity of heat transmitted, due to unit temperature gradient, in unit time under steady conditions in a direction normal to a surface of unit area, when the heat transfer is dependent only on the temperature gradient thermal conductivity = heat flow rate / (distance × temperature... In physics, thermal conductivity, λ, is the quantity of heat transmitted, due to unit temperature gradient, in unit time under steady conditions in a direction normal to a surface of unit area, when the heat transfer is dependent only on the temperature gradient thermal conductivity = heat flow rate / (distance × temperature... An electronic device known as a diode can be formed by joining two nanoscale carbon tubes with different electronic properties. ...

Despite its 2-D nature, Graphene has 3 acoustic phonon modes. The two in-plane modes have a linear dispersion relation, whereas the out of plane mode has a quadratic dispersion relation. Due to this, the T² dependent thermal conductivity contribution of the linear modes is dominated at low temperatures by the T^1.5 contribution of the out of plane mode.^[23] The ballistic thermal conductance of Graphene is isotropic.^[21] The relation between the energy of a system and its corresponding momentum is known as its dispersion relation. ... The relation between the energy of a system and its corresponding momentum is known as its dispersion relation. ...

Mechanical Properties

Utilizing an atomic force microscope, research has recently been able to measure the spring constant of suspended Graphene sheets. Graphene sheets, held together by van der Waals forces, were suspended over silicon dioxide cavities where an AFM tip was probed to test its mechanical properties. Its spring constant was measured to be on the order of 1-5 N/m and its Young's modulus was 0.5 TPa, which differs from bulk graphite. These high values make Graphene very strong and rigid. These intrinsic properties could lead to the possibility of utilizing Graphene for NEMS applications such as pressure sensors, and resonators.^[24] Topographic scan of a glass surface The atomic force microscope (AFM) is a very high-resolution type of scanning probe microscope, with demonstrated resolution of fractions of a nanometer, more than 1000 times better than the optical diffraction limit. ... In physics, Hookes law of elasticity states that if a force (F) is applied to an elastic spring or prismatic rod (with length L and cross section A), its extension is linearly proportional to its tensile stress σ and modulus of elasticity (E): or It is named after the 17th... The title given to this article is incorrect due to technical limitations. ... R-phrases R42 R43 R49 S-phrases S22 S36 S37 S45 S53 Flash point non-flammable Supplementary data page Structure and properties n, εr, etc. ... In solid mechanics, Youngs modulus (E) is a measure of the stiffness of a given material. ... NEMS or nanoelectromechanical systems are similar to MEMS but smaller. ...

Graphene is considered to be the first truly 2D crystal. There has been some discrepancy whether this assertion is truly valid or not. It appears that a single layer of Graphene is in direct contradiction to the Mermin-Wagner theorem. The theorem states that a 2D crystal in a 3D environment would not be able to remain ordered over long distances because of long wavelength fluctuations. It also states that a 2D structure would try to fold-up, or crumple from its instability while seeking a more stable 3D structure. Researchers have observed intrinsic ripples in suspended layers of graphene. It is believed that the ripples are caused by thermal fluctuations in the material. Graphene adjusts to the thermal fluctuations, which could threaten to destroy the structure, by adjusting its bond length to accommodate the fluctuations. It is debatable whether Graphene is truly 2D or not, due to its natural tendency to ripple.^[25][26][13] In quantum field theory and statistical mechanics (at a nonzero temperature), the Mermin-Wagner theorem (also known as Mermin-Wagner-Hohenberg theorem or Coleman theorem) states that continuous symmetries cannot be spontaneously broken in two dimensional theories. ...

Potential Applications

Single Molecule Gas Detection

Graphene makes an excellent sensor due to its 2D structure. The fact that its entire volume is exposed to its surrounding makes it very efficient to detect molecules. Molecule detection is measured indirectly: as a gas molecule adsorbs to the surface of graphene, the location of adsorption will experience a local change in electrical resistance. While this effect occurs in other materials, graphene is superior due to its high electrical conductivity and low noise which makes this change in resistance detectable.^[16] Electrical resistance is a measure of the degree to which an electrical component opposes the passage of current. ...

Graphene Nanoribbons (GNRs)

Graphene nanoribbons are essentially single layers of graphene that are cut in a particular pattern to give it certain electrical properties. Depending on how the un-bonded edges are configured, they can either be in a Z (zigzag) or Armchair configuration. According to recent theoretical simulations, zigzag GNRs are always metallic while armchairs can either be metallic or semiconducting, depending on their width, with the energy gap scaling with the inverse of the GNR width. Indeed, experimental results show that the energy gaps do increase with decreasing GNR width. ^[27] However, to date no experimental results have measured the energy gap of a GNR and identified the exact edge structure. ^[28] Their 2D structure, high electrical and thermal conductivity, and low noise also make GNRs a possible alternative to copper for integrated circuit interconnects. Some research is also being done to create quantum dots by changing the width of GNRs at select points along the ribbon, creating quantum confinement.^[29]

Due to its high electronic quality, graphene has also attracted the interest of technologists who see them as a way of constructing ballistic transistors. In March 2006, Georgia Tech researchers announced that they had successfully built an all-graphene planar field-effect transistor and a quantum interference device.^[30] Graphene nanoribbons may prove generally capable of replacing silicon as a semiconductor in modern technology.^[31] A potential well is the region surrounding a local minimum of potential energy. ... A ballistic transistor is a high-speed electronic switching device through which electrons flow unimpeded, without being slowed down by collisions with atoms as they are in a conventional transistor. ... The Georgia Institute of Technology, commonly known as Georgia Tech, is a public, coeducational research university, part of the University System of Georgia, and located in Atlanta, Georgia, USA, with satellite campuses in Savannah, Georgia, Metz, France, Shanghai, China, and Singapore. ... Large power N-channel field effect transistor The field-effect transistor (FET) is a type of transistor that relies on an electric field to control the shape and hence the conductivity of a channel in a semiconductor material. ... Fig. ... For other uses, see Interference (disambiguation). ...

Integrated Circuits

Graphene has the ideal properties to be an excellent component of integrated circuits. Graphene has a high carrier mobility, as well as low noise allowing it to be utilized as the channel in a FET. The issue is that single sheets of graphene are hard to produce, and even harder to make on top of an appropriate substrate. Researchers are looking into methods of transferring single graphene sheets from their source of origin (mechanical exfoliation on SiO₂ / Si or thermal graphitization of a SiC surface) onto a target substrate of interest.^[32] An integrated circuit (IC) is a thin chip consisting of at least two interconnected semiconductor devices, mainly transistors, as well as passive components like resistors. ... FET can mean: FET, field effect transistor FET, a Mazda piston engine This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...

Cultural References

Graphene was mentioned in comic 1111 of Questionable Content^[33] Questionable Content (abbreviated QC or Q.C.) is a slice-of-life webcomic written and drawn by Jeph Jacques. ...

References

1. ^ Novoselov, K.S. et al. Electric Field Effect in Atomically Thin Carbon Films. Science 306, 666 (2004) doi:10.1126/science.1102896
2. ^ Meyer, J. et al. The structure of suspended graphene sheets. Nature 446, 60-63 (1 March 2007)doi:10.1038/nature05545
3. ^ Novoselov, K.S. et al. Two-dimensional atomic crystals. PNAS 102, 10451-10453 (January 26, 2005) doi:10.1073/pnas.0502848102
4. ^ D. Kasuya, M. Yudasaka, K. Takahashi, F. Kokai and S. Iijima (2002) J. Phys. Chem. B 106:4947.
5. ^ T. J. Bernatowicz, R. Cowsik, P. C. Gibbons, K. Lodders, B. Fegley Jr., S. Amari, and R. S. Lewis (1996) Constraints on stellar grain formation from presolar graphite in the Murchison meteorite, Astrophysical Journal 472:760-782
6. ^ P. Fraundorf and M. Wackenhut (2002) The core structure of presolar graphite onions, Astrophysical Journal Letters 578:L153-156 (astro-ph/0110585,cond-mat/0606093)
7. ^ E. S. Mandell (2007) Electron beam characterization of carbon nanostructures, Dissertation in Physics (University of Missouri - Saint Louis and Rolla).
8. ^ The image source is [1] (slide 17 image b) The height on the image is different. It is equal to 0.549 nm. See also more pictures of graphene here.
9. ^ ^{a b c d e} J.-C. Charlier, P.C. Eklund, J. Zhu, and A.C. Ferrari, “Electron and Phonon Properties of Graphene: Their Relationship with Carbon Nanotubes,” from Carbon Nanotubes: Advanced Topics in the Synthesis, Structure, Properties and Applications, Ed. By A. Jorio, G. Dresselhaus, and M.S. Dresselhaus, Berlin/Heidelberg: Springer-Verlag, 2008
10. ^ ^{a b} Avouris, P., Chen, Z., and Perebeinos, V. Carbon-based electronics. Nature Nano. 2 605-613 (2007)
11. ^ Nair, R. R.; Blake, P. & Grigorenko, A. N. et al. (2008-004-03), "Fine Structure Constant Defines Visual Transparency of Graphene", [[Science (journal)|]], DOI 10.1126/science.1156965
12. ^ "Graphene Gazing Gives Glimpse Of Foundations Of Universe", ScienceDaily, 2008-04-04, <http://www.sciencedaily.com/releases/2008/04/080403140918.htm>. Retrieved on 6 April 2008
13. ^ ^{a b c d e} Geim, A. K. and Novoselov, K. S. The rise of graphene. Nature Mater. 6, 183-191 (2007)
14. ^ ^{a b c d} Novoselov, K. S. et al. Two-dimensional gas of massless Dirac fermions in graphene. Nature 438, 197-200 (2005)
15. ^ S.V. Morozov, et al. Giant Intrinsic Carrier Mobilities in Graphene and Its Bilayer. Phys. Rev. Lett. 100, 016602 (2008)
16. ^ ^{a b} Schedin, F. et al. Detection of individual gas molecules adsorbed on graphene. Nature Mater. 6, 652-655 (2007)
17. ^ Zhang, Y., Tan, Y. W., Stormer, H. L., and Kim, P. Experimental observation of the quantum Hall effect and Berry’s phase in graphene. Nature 438, 201-204 (2005)
18. ^ Graphene Oxide Paper, Technology Transfer Program, Northwestern University
19. ^ Sandip Niyogi, Elena Bekyarova, Mikhail E. Itkis, Jared L. McWilliams, Mark A. Hamon, and Robert C. Haddon . Solution Properties of Graphite and Graphene. J. Am. Chem. Soc. 128(24) pp. 7720–7721 (2006); (Communication) doi:10.1021/ja060680r
20. ^ Balandi, A.A., Ghosh, S., Bao, W., Calizo, I., Teweldebrahn, D., Miao, F., and Lau, C.N. "Superior Thermal Conductivity of Single-Layer Graphene", Nano Letters ASAP (2008)
21. ^ ^{a b} Saito, K., Nakamura, J., and Natori, A. "Ballistic thermal conductance of a graphene sheet", Physical Review B 76 115409 (2007)
22. ^ "Graphite and Precursors", By Pierre Delhaes
23. ^ ^{a b} Mingo N., Broido, D.A. "Carbon Nanotube Ballistic Thermal Conductance and Its Limits" Physical Review Letters 95, 096105 (2005)
24. ^ Frank, I. W., Tanenbaum, D. M., Van Der Zande, A.M., and McEuen, P. L. Mechanical properties of suspended graphene sheets. J. Vac. Sci. Technol. B 25, 2558-2561 (2007)
25. ^ Carlsson, J. M. Graphene: Buckle or break. Nature Materials, 6(11), 801-802 (2007)
26. ^ Fasolino, A., Los, J. H., & Katsnelson, M. I. Intrinsic ripples in graphene. Nature Materials, 6(11), 858-861 (2007)
27. ^ Han., M.Y., Özyilmaz, B., Zhang, Y., and Kim, P. Energy Band-Gap Engineering of Graphene Nanoribbons. Phys. Rev. Lett. 98, 206805 (2007)
28. ^ As of Thursday, February 28, 2008
29. ^ Wang, Z. F., Shi, Q. W., Li, Q., Wang, X., Hou, J. G., Zheng, H., et al. Z-shaped graphene nanoribbon quantum dot device. Applied Physics Letters, 91(5), 053109 (2007)
30. ^ Carbon-Based Electronics: Researchers Develop Foundation for Circuitry and Devices Based on Graphite March 14, 2006 gtresearchnews.gatech.edu Link
31. ^ Bullis, Kevin (2008-1-28). "Graphene Transistors". Technology Review. Cambridge: MIT Technology Review, Inc. Retrieved on 2008-02-18. 
32. ^ Chen, J., Ishigami, M., Jang, C., Hines, D. R., Fuhrer, M. S., and Williams, E. D. Printed graphene circuits. Advanced Materials, 19(21), 3623-3627 (2007)
33. ^ Jacques, Jeph (2008). Buckeyballs of Flavor(#1111). questionablecontent.net. Retrieved on 2008-4-01.

A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... The Journal of the American Chemical Society (usually abbreviated as , or JACS), is a peer-reviewed scientific journal, published since 1879 by the American Chemical Society. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Technology Review is an innovation and technology magazine affiliated with the Massachusetts Institute of Technology. ... “MIT” redirects here. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance to the Gregorian calendar. ... is the 49th day of the year in the Gregorian calendar. ...

See also

• Aromaticity
• Fullerenes
• Polycyclic aromatic hydrocarbons
• Carbon nanotubes
• Graphene nanoribbons
• Graphene Oxide Paper

Aromaticity is a chemical property in which a conjugated ring of unsaturated bonds, lone pairs, or empty orbitals exhibit a stabilization stronger than would be expected by the stabilization of conjugation alone. ... The Icosahedral Fullerene C540 C60 and C-60 redirect here. ... An illustration of typical polycyclic aromatic hydrocarbons. ... 3D model of three types of single-walled carbon nanotubes. ... Graphene Oxide Paper is a composite material with stiffness and strength superior to all other materials, with the exception of diamond. ...

External links

• Band structure of graphene [2].
• The Rise of Graphene A review article by A.K. Geim & K.S. Novoselov in Nature Materials 6, 183-191 (2007).
• Image Gallery - Graphite and Graphene
• BBC News report
• Electrons lose their mass in carbon sheets Physics Web (09-Nov-2005)
• Potential for graphene computer chips, with explanation of technical issues/problems
• Quantum weirdness on the end of your pencil Philip Ball, New Scientist Magazine issue 2559, (8 July 2006)
• Talks at the Electronic Properties of Graphene conference (January 8-19, 2007)
• [3] Physics World article concerning minimum conductance
• Carbon nanosheets promise super-fast chips Graphene has the highest electronic quality among all known materials, New Scientist, 8 January 2008
• Researchers leap a nano hurdle - ABC Online (Australia) Development of a simpler method of graphene production.
• Is Graphene the New Silicon? National Science Foundation, March 27, 2008