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The blackest of them all..

August 5, 2014

Vantablack (from Vertically Aligned Nano Tube Array) absorbs upto 99.965% of all radiation it receives and is now the blackest material known. It is blacker than NASA’s “super-black” (99%) and, I suppose, will be the start of ultra-black.

The uncoated part of this foil remains three-dimensional but the coated part reflects virtually no light and appears flat.

Piece of foil partially coated with Vantablack

Vantablack is manufactured by Surrey Nano Systems and is already in production.

The Engineer: Vantablack, a so-called ‘super black’ coating from Surrey Nanosystems, combines exceptionally low mass, thermal stability and an ability to absorb 99.96 per cent of incident radiation. Consequently, the coating is suited to applications including apertures, baffles, cold shields and Micro Electro Mechanical Systems (MEMS)–type optical sensors.

The material also overcomes limitations encountered in the manufacture of super-black carbon nanotube-based materials, where high temperatures precluded direct application to sensitive electronics or materials with relatively low melting points. This, along with poor adhesion, prevented their application to space and airborne instrumentation.

There is no established blackness scale. Black paint reflects almost 10% of incident light. Newly laid asphalt reflects 2 – 5% depending upon surface composition. Carbon black (polycrystalline carbon resulting from incomplete combustion) reflects only 1% of incident light. Though we take blackness to be the absence of reflection of radiation, material may reflect radiation at a different wave-length to the incident radiation. All light photons that are absorbed must eventually become heat and all bodies will radiate heat (infra-red) dependent upon only their surface temperature. In physics, a black body is theoretical and absorbs all incident electromagnetic radiation, at all wavelengths and all angles of incidence. In practice such a body can’t exist.

NASA Superblack: NASA engineers have produced a material that absorbs on average more than 99 percent of the ultraviolet, visible, infrared, and far-infrared light that hits it — a development that promises to open new frontiers in space technology. …… 

The nanotech-based coating is a thin layer of multi-walled carbon nanotubes, tiny hollow tubes made of pure carbon about 10,000 times thinner than a strand of human hair. They are positioned vertically on various substrate materials much like a shag rug. The team has grown the nanotubes on silicon, silicon nitride, titanium, and stainless steel, materials commonly used in space-based scientific instruments. (To grow carbon nanotubes, Goddard technologist Stephanie Getty applies a catalyst layer of iron to an underlayer on silicon, titanium, and other materials. She then heats the material in an oven to about 1,382 degrees Fahrenheit. While heating, the material is bathed in carbon-containing feedstock gas.)

The tests indicate that the nanotube material is especially useful for a variety of spaceflight applications where observing in multiple wavelength bands is important to scientific discovery. One such application is stray-light suppression. The tiny gaps between the tubes collect and trap background light to prevent it from reflecting off surfaces and interfering with the light that scientists actually want to measure. Because only a small fraction of light reflects off the coating, the human eye and sensitive detectors see the material as black.

In particular, the team found that the material absorbs 99.5 percent of the light in the ultraviolet and visible, dipping to 98 percent in the longer or far-infrared bands. “The advantage over other materials is that our material is from 10 to 100 times more absorbent, depending on the specific wavelength band,” Hagopian said.

Currently, instrument developers apply black paint to baffles and other components to help prevent stray light from ricocheting off surfaces. However, black paints absorb only 90 percent of the light that strikes it. The effect of multiple bounces makes the coating’s overall advantage even larger, potentially resulting in hundreds of times less stray light.

In addition, black paints do not remain black when exposed to cryogenic temperatures. They take on a shiny, slightly silver quality, said Goddard scientist Ed Wollack, who is evaluating the carbon-nanotube material for use as a calibrator on far-infrared-sensing instruments that must operate in super-cold conditions to gather faint far-infrared signals emanating from objects in the very distant universe. If these instruments are not cold, thermal heat generated by the instrument and observatory, will swamp the faint infrared they are designed to collect.

 

 

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From graphene to borophene

January 29, 2014

Technology development waves

The discovery of graphene is leading to a new excitement in materials research. I have a notion that technology advances take place in step waves, where each step is both enabled and constrained by the materials available. Each time a new material (or material family is discovered), technology development starts very fast and then tapers off until another material comes along and ignites a new development wave.

Boron is Carbon’s neighbour in the periodic table and the discovery of graphene has ignited studies to see if a similar variation of boron would be possible.

Boron is a Group 13 element that has properties which are borderline between metals and non-metals (semimetallic). It is a semiconductor rather than a metallic conductor. Chemically it is closer to silicon than to aluminium, gallium, indium, and thallium. Crystalline boron is inert chemically and is resistant to attack by boiling HF or HCl. When finely divided it is attacked slowly by hot concentrated nitric acid.

Boron, Symbol: B, Atomic number: 5, Atomic weight: 10.811, solid at 298 K

“Boron has one fewer electron than carbon and as a result can’t form the honeycomb lattice that makes up graphene. For boron to form a single-atom layer, theorists suggested that the atoms must be arranged in a triangular lattice with hexagonal vacancies — holes — in the lattice.”

A new paper shows that borophene is possible – now it just has to be made!

Zachary A. Piazza, Han-Shi Hu, Wei-Li Li, Ya-Fan Zhao, Jun Li, Lai-Sheng Wang.Planar hexagonal B36 as a potential basis for extended single-atom layer boron sheets. Nature Communications, 2014; 5 DOI: 10.1038/ncomms4113

Brown University Press Release:

Unlocking the secrets of the B36 cluster
A 36-atom cluster of boron, left, arranged as a flat disc with a hexagonal hole in the middle, fits the theoretical requirements for making a one-atom-thick boron sheet, right, a theoretical nanomaterial dubbed “borophene.” Credit: Wang lab/Brown University

Graphene, a sheet of carbon one atom thick, may soon have a new nanomaterial partner. In the lab and on supercomputers, chemical engineers have determined that a unique arrangement of 36 boron atoms in a flat disc with a hexagonal hole in the middle may be the preferred building blocks for “borophene.”

Researchers from Brown University have shown experimentally that a boron-based competitor to graphene is a very real possibility.

Lai-Sheng Wang, professor of chemistry at Brown and his research group, which has studied boron chemistry for many years, have now produced the first experimental evidence that such a structure is possible. In a paper published on January 20 in Nature Communications, Wang and his team showed that a cluster made of 36 boron atoms (B36) forms a symmetrical, one-atom thick disc with a perfect hexagonal hole in the middle.

“It’s beautiful,” Wang said. “It has exact hexagonal symmetry with the hexagonal hole we were looking for. The hole is of real significance here. It suggests that this theoretical calculation about a boron planar structure might be right.”

It may be possible, Wang said, to use B36 basis to form an extended planar boron sheet. In other words, B36 may well be the embryo of a new nanomaterial that Wang and his team have dubbed “borophene.”

“We still only have one unit,” Wang said. “We haven’t made borophene yet, but this work suggests that this structure is more than just a calculation.” ……..

Wang’s experiments showed that the B36 cluster was something special. It had an extremely low electron binding energy compared to other boron clusters. The shape of the cluster’s binding spectrum also suggested that it was a symmetrical structure. ……..

…… That structure also fits the theoretical requirements for making borophene, which is an extremely interesting prospect, Wang said. The boron-boron bond is very strong, nearly as strong as the carbon-carbon bond. So borophene should be very strong. Its electrical properties may be even more interesting. Borophene is predicted to be fully metallic, whereas graphene is a semi-metal. That means borophene might end up being a better conductor than graphene.

“That is,” Wang cautions, “if anyone can make it.”

Abstract: Boron is carbon’s neighbour in the periodic table and has similar valence orbitals. However, boron cannot form graphene-like structures with a honeycomb hexagonal framework because of its electron deficiency. Computational studies suggest that extended boron sheets with partially filled hexagonal holes are stable; however, there has been no experimental evidence for such atom-thin boron nanostructures. Here, we show experimentally and theoretically that B36 is a highly stable quasiplanar boron cluster with a central hexagonal hole, providing the first experimental evidence that single-atom layer boron sheets with hexagonal vacancies are potentially viable. Photoelectron spectroscopy of B36− reveals a relatively simple spectrum, suggesting a symmetric cluster. Global minimum searches for B36− lead to a quasiplanar structure with a central hexagonal hole. Neutral B36 is the smallest boron cluster to have sixfold symmetry and a perfect hexagonal vacancy, and it can be viewed as a potential basis for extended two-dimensional boron sheets.

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No end to new materials with super-strength

October 10, 2013

From the days of the alchemists and then the metallurgists who mixed different materials – often in the molten state – and then to the chemists we have now moved into the age when materials are designed in the lab to have desired properties. The challenge then is to synthesise the desired composition with the atomic structure required and then to devise manufacturing processes for the materials.

“A material called carbyne could be stronger even than graphene or diamond, according to researchers who have calculated its properties”, reports the BBC.

Carbyne is a chain of carbon atoms held together by double or alternating single and triple chemical bonds.

In their paper, Boris Yakobson and colleagues from Rice University in Houston show that carbyne’s tensile strength – the ability to withstand stretching – surpasses that of “any other known material” and is double that of graphene, the flat sheet of carbon atoms that is often held up as a “supermaterial”.

They also calculated that carbyne has twice the tensile stiffness of graphene and carbon nanotubes and nearly three times that of diamond.

It should display a number of other useful properties say the researchers. For example, it could be turned into a magnetic semiconductor (these are materials with electrical conductivity between that of a metal and an insulator like glass) and could be used as a sensor to detect twisting.

Some scientists have reported synthesising small amounts of carbyne in the lab, but it was thought to be extremely unstable. And some chemists have suggested that two strands coming into contact could react explosively.

“Our intention was to put it all together, to construct a complete mechanical picture of carbyne as a material,” said Vasilii Artyukhov, also from Rice University.

“The fact that it has been observed tells us it’s stable under tension, at least, because otherwise it would just fall apart.”

Mingjie Liu , Vasilii I. Artyukhov , Hoonkyung Lee ,Fangbo Xu , and Boris I. Yakobson, Carbyne From First Principles: Chain of C atoms, a Nanorod or a Nanorope,

ACS Nano,  DOI: 10.1021/nn404177r, October 5, 2013

Abstract: We report an extensive study of the properties of carbyne using first-principles calculations. We investigate carbyne’s mechanical response to tension, bending, and torsion deformations. Under tension, carbyne is about twice as stiff as the stiffest known materials and has an unrivaled specific strength of up to 7.5×10^7 N∙m/kg, requiring a force of ~10 nN to break a single atomic chain. Carbyne has a fairly large room-temperature persistence length of about 14 nm. Surprisingly, the torsional stiffness of carbyne can be zero but can be ‘switched on’ by appropriate functional groups at the ends. Further, under appropriate termination, carbyne can be switched into a magnetic-semiconductor state by mechanical twisting. We reconstruct the equivalent continuum-elasticity representation, providing the full set of elastic moduli for carbyne, showing its extreme mechanical performance (e.g. a nominal Young’s modulus of 32.7 TPa with an effective mechanical thickness of 0.772 Å). We also find an interesting coupling between strain and band gap of carbyne, which is strongly increased under tension, from 3.2 to 4.4 eV under a 10% strain. Finally, we study the performance of carbyne as a nanoscale electrical cable, and estimate its chemical stability against self-aggregation, finding an activation barrier of 0.6 eV for the carbyne–carbyne cross-linking reaction and an equilibrium cross-link density for two parallel carbyne chains of 1 cross-link per 17 C atoms (2.2 nm).

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Beijing turns the screw on rare earth materials

February 18, 2011
Wen Jiabao (温家宝), Chinese Premier

Wen Jiabao: Image via Wikipedia

The Chinese Government is taking steps to keep control of the development, production and export of rare earth materials under state corporations.  Until production from alternate sources in Vietnam, Afghanistan, India, Sweden and other countries are ramped up, production and export of rare earth materials is likely to be used as an instrument of Chinese foreign policy. This leaves Japan particularly vulnerable and is likely to speed up the Japanes investment in the production of these materials in other countries.

Asahi reports:

CHONGQING, China–In a move likely to strain already scarce supplies of rare earth materials worldwide, China will introduce new controls on production and export of the elements crucial for electronics and environmental technologies.

According to the state-run Xinhua News Agency, Chinese Premier Wen Jiabao instructed a State Council standing committee meeting Wednesday to designate rare earth materials as an important strategic resource, and implement measures to strengthen government control over the materials.

With many players fighting over the largely unregulated market, from state corporations to small firms, Beijing, worried about smuggling and rampant environmental destruction, has decided to step in. Beijing plans to grant authority to develop and manage rare earths to state corporations to allow better oversight and control.

The state will also decide export volumes each year after assessing domestic demand and price trends in global markets. Watchers have said the measures are primarily designed to allow Beijing to use its control over the materials as a strategic diplomatic tool.

China has already taken steps to further its control over rare earths production this year, by designating Jiangxi province a nationally administered mining district for rare earths. Under the arrangement, natural deposits will be monitored by Beijing, and exploration and mining will be conducted under close control by the government.

Related: China and the use of rare earth elements trade as a tool for diplomacy

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Molybdenite to challenge graphene?

January 31, 2011
Mineral molybdenite from collection of Nationa...

Mineral molybdenite: Image via Wikipedia

A new paper from researchers at Ecole Polytechnique Federale de Lausanne about a new material which could challenge graphene for transistors.

Single-layer MoS2 transistors, by B. Radisavljevic, A. Radenovic, J. Brivio, V. Giacometti & A. Kis, Nature Nanotechnology (2011) doi:10.1038/nnano.2010.279

Physorg reports:

Smaller and more energy-efficient electronic chips could be made using molybdenite. In an article appearing online January 30 in the journal Nature Nanotechnology, EPFL’s Laboratory of Nanoscale Electronics and Structures (LANES) publishes a study showing that this material has distinct advantages over traditional silicon or graphene for use in electronics applications.

A model showing how molybdenite can be integrated into a transistor. Credit: EPFL

Research carried out in the Laboratory of Nanoscale Electronics and Structures (LANES) has revealed that molybdenite, or MoS2, is a very effective semiconductor. This mineral, which is abundant in nature, is often used as an element in steel alloys or as an additive in lubricants. But it had not yet been extensively studied for use in electronics.

“It’s a two-dimensional material, very thin and easy to use in nanotechnology. It has real potential in the fabrication of very small transistors, light-emitting diodes (LEDs) and solar cells,” says EPFL Professor Andras Kis, whose LANES colleagues M. Radisavljevic, Prof. Radenovic et M. Brivio worked with him on the study. He compares its advantages with two other materials:silicon, currently the primary component used in electronic and computer chips, and graphene, whose discovery in 2004 earned University of Manchester physicists Andre Geim and Konstantin Novoselov the 2010 Nobel Prize in Physics.

One of molybdenite’s advantages is that it is less voluminous than silicon, which is a three-dimensional material. “In a 0.65-nanometer-thick sheet of MoS2, the electrons can move around as easily as in a 2-nanometer-thick sheet of silicon,” explains Kis. “But it’s not currently possible to fabricate a sheet of silicon as thin as a monolayer sheet of MoS2.” Another advantage of molybdenite is that it can be used to make transistors that consume 100,000 times less energy in standby state than traditional silicon transistors. A semi-conductor with a “gap” must be used to turn a transistor on and off, and molybdenite’s 1.8 electron-volt gap is ideal for this purpose.

The existence of this gap in molybdenite also gives it an advantage over graphene.

Read Article


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The never ending wonders of Carbon

January 27, 2011

Not just all life as we know it and coal and diamonds and graphite and carbon nanotubes and now the new wonder-world of  graphene.

Carbon also has the highest melting and sublimation point of all elements. At atmospheric pressure it has no melting point as its triple point is at 10.8 ± 0.2 MPa and 4600 ± 300 K, so it sublimates at about 3900 K.

File:Carbon basic phase diagram.png

Theoretical phase diagram of carbon: Wikipedia

Evidence is mounting that a new crystal form of carbon – body-centered tetragonal (bct) – something between diamond and graphene must exist. Simulations show that it must. It is now up to experimentalists to prove it.

Image: From "Ab Initio study of the formation of transparent carbon under pressure," by Xiang-Feng Zhou et al., in Physical Review B, Vol. 82, No. 13; October 29, 2010

From Scientific American:

… Now evidence is mounting that there is yet another crystal structure to add to carbon’s catalogue of wonders: a material that could find applications in mechanical components whose hardness varies depending on the pressure to which they are exposed.

This new type of carbon was first observed in 2003, when researchers placed graphite, a stacking of chicken-wire-shaped networks of carbon atoms, under high pressure at room temperature. Under this “cold” compression, the graphite began to assume a hybrid form, between that of graphene and of diamond, but its exact nature was unknown.

Two computer simulation studies now suggest that cold-compressed graphite contains crystals of a structure called body-centered tetragonal, or bct, in addition to another type called M carbon. In bct, groups of four atoms are arranged in a square. The squares are stacked in an offset manner, and each square forms chemical bonds with four squares in the layers above and four below. A team led by Hui-Tian Wang of Nankai University in Tianjin, China, showed that during cold compression the transition to bct carbon results in a release of energy, which means it is likely to happen in the real world.

A Japanese and American team also conducted a simulation in which bct carbon produced x-ray patterns similar to those seen in the 2003 study. …. Whether bct carbon exists or can be synthesized in its pure form “is still a task for experimentalists to test.” 

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A metallic glass tougher than steel

January 11, 2011

An exciting new paper in materials technology –

A damage-tolerant glass by Marios D. Demetriou, Maximilien E. Launey, Glenn Garrett, Joseph P. Schramm, Douglas C. Hofmann, William L. Johnson & Robert O. Ritchie

Nature Materials (2011) doi:10.1038/nmat2930
From EurekAlert:

A new type of damage-tolerant metallic glass, demonstrating a strength and toughness beyond that of any known material, has been developed and tested by a collaboration of researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab)and the California Institute of Technology. What’s more, even better versions of this new glass may be on the way. The new metallic glass is a microalloy featuring palladium, a metal with a high “bulk-to-shear” stiffness ratio that counteracts the intrinsic brittleness of glassy materials.

Glassy materials have a non-crystalline, amorphous structure that make them inherently strong but invariably brittle. Whereas the crystalline structure of metals can provide microstructural obstacles (inclusions, grain boundaries, etc.,) that inhibit cracks from propagating, there’s nothing in the amorphous structure of a glass to stop crack propagation. The problem is especially acute in metallic glasses, where single shear bands can form and extend throughout the material leading to catastrophic failures at vanishingly small strains.

In earlier work, the Berkeley-Cal Tech collaboration fabricated a metallic glass, dubbed “DH3,” in which the propagation of cracks was blocked by the introduction of a second, crystalline phase of the metal. This crystalline phase, which took the form of dendritic patterns permeating the amorphous structure of the glass, erected microstructural barriers to prevent an opened crack from spreading. In this new work, the collaboration has produced a pure glass material whose unique chemical composition acts to promote extensive plasticity through the formation of multiple shear bands before the bands turn into cracks.

“Our game now is to try and extend this approach of inducing extensive plasticity prior to fracture to other metallic glasses through changes in composition,” Ritchie says. “The addition of the palladium provides our amorphous material with an unusual capacity for extensive plastic shielding ahead of an opening crack. This promotes a fracture toughness comparable to those of the toughest materials known. The rare combination of toughness and strength, or damage tolerance, extends beyond the benchmark ranges established by the toughest and strongest materials known.”

The initial samples of the new metallic glass were microalloys of palladium with phosphorous, silicon and germanium that yielded glass rods approximately one millimeter in diameter. Adding silver to the mix enabled the Cal Tech researchers to expand the thickness of the glass rods to six millimeters. The size of the metallic glass is limited by the need to rapidly cool or “quench” the liquid metals for the final amorphous structure.

“The rule of thumb is that to make a metallic glass we need to have at least five elements so that when we quench the material, it doesn’t know what crystal structure to form and defaults to amorphous,” Ritchie says.

The new metallic glass was fabricated by co-author Demetriou at Cal Tech in the laboratory of co-author Johnson. Characterization and testing was done at Berkeley Lab by Ritchie’s group.

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In spite of strong yen, Japan Inc’s sales and profits soar

November 9, 2010

From Asahi News:

Japanese companies posted huge increases in sales and profits in the first half of fiscal 2010, but the “China risks” coupled with the strong yen threaten to pummel performances in the second half.

photo

Toyota Motor Executive Vice President Satoshi Ozawa releases business results in Tokyo on Friday. (The Asahi Shimbun)

Aggregate sales rose 11.6 percent from a year ago, while pretax profits increased 131.7 percent and net profits soared 179.8 percent, according to Nikko Cordial Securities Inc.’s survey of 650 companies listed in the First Section of the Tokyo Stock Exchange that had released their half-year results by Thursday.

But the companies say the business turnaround could be short-lived depending on what happens in China. Chinese exports of rare earth minerals, vital ingredients in high-tech production, were stalled in September when Beijing demanded the release of a Chinese captain whose fishing boat rammed Japan Coast Guard vessels near the disputed Senkaku Islands in the East China Sea. The de facto ban on rare earth exports to Japan came on top of China’s increasingly tight export quotas on the materials.

Chinese imports account for more than 80 percent of clothes sold in supermarkets and other stores operated by Aeon.

Many manufacturers say they have secured rare earth supplies for the short term, but a prolonged delay in delivery would inevitably hit them hard.

Japan is pursuing alternative supply sources in India and elsewhere to reduce Japan’s reliance on China, which accounts for 97 percent of the world’s supply. But such development will take time.

While trading firm Toyota Tsusho Corp. is developing rare earth mines in Vietnam, Executive Vice President Kenji Takanashi said the work “will take at least two to three years.”

Meanwhile, export-oriented companies say their efforts to fend off the impact from the yen’s appreciation are reaching their limits. Toyota Motor Corp., for example, expects currency exchange losses to total 320 billion yen ($3.94 billion) for the year ending in March, which will more than offset its estimated profit rise from sales increases totaling 280 billion yen.

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Now fluorographene from Graphene Nobel winners

November 9, 2010

A new paper by the Graphene Nobel winners in the Journal Small:

Fluorographene: A Two-Dimensional Counterpart of Teflon, by Rahul R. Nair, Wencai Ren, Rashid Jalil, Ibtsam Riaz, Vasyl G. Kravets, Liam Britnell, Peter Blake, Fredrik Schedin, Alexander S. Mayorov, Shengjun Yuan, Mikhail I. Katsnelson, Hui-Ming Cheng, Wlodek Strupinski, Lyubov G. Bulusheva, Alexander V. Okotrub, Irina V. Grigorieva, Alexander N. Grigorenko, Kostya S. Novoselov, Andre K. Geim. Article first published online: 4 NOV 2010, DOI: 10.1002/smll.201001555

Abstract

A stoichiometric derivative of graphene with a fluorine atom attached to each carbon is reported. Raman, optical, structural, micromechanical, and transport studies show that the material is qualitatively different from the known graphene-based nonstoichiometric derivatives. Fluorographene is a high-quality insulator (resistivity >1012Ω) with an optical gap of 3 eV. It inherits the mechanical strength of graphene, exhibiting a Young’s modulus of 100 N m−1 and sustaining strains of 15%. Fluorographene is inert and stable up to 400 °C even in air, similar to Teflon.

Graphane crystal. This novel two-dimensional material is obtained from graphene (a monolayer of carbon atoms) by attaching hydrogen atoms (red) to each carbon atoms (blue) in the crystal. (Credit: Mesoscopic Physics Group, Prof. Geim - University of Manchester)

Science Daily. University of Manchester scientists have created a new material which could replace or compete with Teflon in thousands of everyday applications. Professor Andre Geim, who along with his colleague Professor Kostya Novoselov won the 2010 Nobel Prize for graphene — the world’s thinnest material, has now modified it to make fluorographene — a one-molecule-thick material chemically similar to Teflon.

Fluorographene is fully-fluorinated graphene and is basically a two-dimensional version of Teflon, showing similar properties including chemical inertness and thermal stability. Teflon is a fully-fluorinated chain of carbon atoms. These long molecules bound together make the polymer material that is used in a variety of applications including non-sticky cooking pans. The Manchester team managed to attach fluorine to each carbon atom of graphene. To get fluorographene, the Manchester researchers first obtained graphene as individual crystals and then fluorinated it by using atomic fluorine. To demonstrate that it is possible to obtain fluorographene in industrial quantities, the researchers also fluorinated graphene powder and obtained fluorographene paper.

Fluorographene turned out to be a high-quality insulator which does not react with other chemicals and can sustain high temperatures even in air.

Industrial scale production of fluorographene is not seen as a problem as it would involve following the same steps as mass production of graphene. The Manchester researchers believe that the next important step is to make proof-of-concept devices and demonstrate various applications of fluorographene. Professor Geim added: “There is no point in using it just as a substitute for Teflon. The mix of the incredible properties of graphene and Teflon is so inviting that you do not need to stretch your imagination to think of applications for the two-dimensional Teflon. The challenge is to exploit this uniqueness.”

 

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Graphene: Urban legend in the making?

October 8, 2010

As I posted earlier, the Nobel Prize in Physics 2010 was awarded jointly to Andre Geim and Konstantin Novoselov “for groundbreaking experiments regarding the two-dimensional material graphene”

It seems there is no controversy that “the first graphene samples formed were produced by pulling atom thick layers from a sample of graphite using sticky tape”.

But whether the graphite sample was actually lead flakes from a pencil and whether the sticky tape was actually Scotch tape is more uncertain. Nevertheless, it is now the stuff of urban legend and the subject of cartoons.

 

Nobel physics 2010.png

sticky tape + pencil = graphene

 

http://blogs.nature.com/strippedscience/2010/10/06/nobel-prize-in-physics-2010-catoon

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