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Nobel Prize skirmishes continue as committee backtracks on history

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The 2010 Nobel prize for physics has been awarded for research on graphene, a single atomic layer of carbon that holds potential for use in electronics, but skirmishes over the history of the field have only just begun. Eleven days after Nature revealed errors in the Nobel Prize committee’s background document explaining the award of the prize to Andre Geim and Konstantin Novoselov of the University of Manchester, UK, the committee issued a revised version.

No erratum was released, but a comparison of the new document with the old shows that several sentences discussing the history of the field have been modified. For example, the new version omits a disputed statement that graphene was not thought to be stable prior to its isolation by Geim and Novoselov in a highly-cited 2004 paper in Science. It also tones down the claim that the 2004 work came as a “complete surprise” to the physics community; now, it was merely a “surprise.” The committee has additionally corrected errors in two disputed figure captions that appeared to exaggerate contributions by Geim and Novoselov at the expense of work by other researchers.

Hanns-Peter Boehm, a chemist at the Ludwig Maximilians University of Munich, whose 1962 work on graphene is cited by the Nobel prize committee, says the changes are an improvement. “The committee acknowledges that some researchers had thought that it should be possible, in principle, to prepare graphene monolayers,” he says. But he questions a statement that remains unchanged saying that following work done in the 1960s “there were doubts” that “single layers could be isolated in such a way that electrical measurements could be performed on them”. “There is no citation for such doubts and I cannot remember having read of them,” says Boehm.


As the Nobel committee struggles to chart an authoritative history of the field, competing versions of events are on offer from the experts. In Geim’s Nobel Prize lecture, posted online today, Geim traces his decision to work on graphene to three influences; papers he had read on metallic electronics, an explosion of interest on carbon nanotubes including work by Japanese physicist Sumio Iijima, and a review article on graphite by Mildred Dresselhaus of MIT. He suggests that his and Novoselov’s 2004 paper marked the first time that a single atomic layer of carbon had been isolated in a totally unambiguous way, and he repeats the suggestion that there was some reason before that to think graphene might not be stable. “This is probably why it took so long for graphene to be isolated,” he says.

Meanwhile Walt de Heer of the Georgia Institute of Technology, who wrote a letter to the Nobel prize committee in November to object to several statements in its document, today released his account of the history of the field in a paper to mark the award of the Materials Research Society Medal for his own work on graphene. In the paper, he describes a long history of attempts to isolate graphene, and says that the method of isolation that Geim and Novoselov published in 2004 was similar to a method that his own group proposed in 2001, and that Rod Ruoff of the University of Texas at Austin pioneered in 1999.

Boehm points out that the Nobel prize committee appears to have confused this method with a different and easier method of isolating graphene – by peeling layers of graphite off with Scotch tape. Boehm says the Scotch tape method was also known of in the 1960s. It was used by Geim and Novoselov in a 2005 paper to isolate graphene and perform electronic measurements.

Boehm says in his view, the Nobel committee “has not exercised the care expected for such a decision”. But he nevertheless believes that the award can be justified by Geim and Novoselov’s electronic measurements on graphene. “These were certainly new with, in large part, unexpected results,” he says. “We had, in 1962, no application in mind.”

Image: Andre Geim / Prolineserver 2010, Wikipedia/Wikimedia Commons

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  1. Report this comment

    Reginald B. Little said:

    RB Little was ignored and left out of all of the history surrounding graphene formation and isolation. But the discarded stone is the cornerstone!

    As Geim mentioned in his Nobel Lecture, Brodie formed graphene oxide in suspension in 1859, but Brodie did not realize his separation of layers and he believed he formed something he called graphon 33. Brodie’s method intrinsically destroys the crystallinity of the carbon atoms in the layers due to release of some carbon dioxide by complete oxidation of some of the carbon atoms by the acids. Stronger acids enhance separation of the graphene layers of graphite but also damage the layers by completely oxidizing many carbon atoms to CO2 with release of CO2 gas!

    One hundred years later, Boehm in 1962 forms graphene oxide similar to Brodie’s method and goes on to reduce it with hydrazine. But Boehm’s reduced graphene oxide lacks the highly oriented crystallinity over large areas of the original graphene layers in the graphite prior to the oxidation due to the formation of voids as many carbon atoms are completely oxidized to carbon dioxide and released as CO2 gas. So the reduced graphene oxide of Boehm is not atomically flat, sp2, crystalline, hexagonal large-area arrays of carbon as in the graphene layers of the original graphite. In other words the acid oxidation of Brodie and Boehm destroys the crystallinity over large areas of the graphene layers in graphite with the inability to recover the crystalline lattice over large scale by simple chemical reduction of the defective graphite oxide. Maybe high temperature annealing Boehm’s graphite oxide could have formed graphene but this risk curling into fullerenes, carbon nanotubes or carbon scrolls. Therefore such reduced graphite oxide of Boehm is not in principle graphene, as it is not crystalline, missing many carbon atoms! Moreover this supposed graphene was formed in aqueous solution, not free standing as RBL later did in 2002.

    Multilayers of graphene on some transition metals, silicon carbide and intercalated graphites were also formed in 1960s and 1970s. But no single layer graphene was achieved during this time with isolation from the substrate.

    Ruoff rubbed micron graphite pillars in 1999, but no single layer was ever produced by this process. Pulling and rubbing are different physical processes.

    RB Little in 2000 (in US Patent entitled: “Magnetic Production of Carbon Nanotubes and Filaments”), realized and proposed magnetic single layer graphene (expitaxial) catalytic formation on ferrometals and other transition metals nanoparticles (Zn, Cu, Au,Ag,Os, Tc, Ir, Ru, Rh, Pd, and Pt) while unraveling the mechanism of single wall carbon nanotube formation. RBL gave explicit conditions for selective single layer graphene formation to exclusion of single wall carbon nanotube formation. This work of RBL was the first ever explicit account for single layer graphene as it was derived directly from consideration of single wall carbon nanotube formation mechanics. This 2000 proposed epitaxy of single layer graphene by RBL has been later demonstrated by many other groups. Later in 2009 and 2010 some of the best large area single layer graphene has been formed by this catalytic method of RB Little using Ni and Cu single crystal catalysts!

    de Heer, in his 2001 proposal, defined and distinguished graphite ribbons and graphene ribbons and then de Heer went on to make the graphite ribbons (not graphene ribbons) the subject of his 2001 proposal, giving no details of how to form single layer graphene ribbons in 2001, but giving many conditions and methods to form thin graphite ribbons. The 2001 proposal gives many details of the electronics and device fabrication of such graphite ribbons. Later (2-3 years), de Heer developed his silicon carbide process to form single layer epitaxial graphene and published single layer epitaxial graphene after 2003.

    In 2002, Geim assigned Jiang the PhD project to thin graphite by polishing. Jiang in 2002 achieved only 5-10 micron thin graphite. Geim told Jiang to use high density graphite rather than highly oriented graphite. In 2002, Shklyarevskii (of Geim’s group) allegedly realized the need for highly oriented pyrolytic graphite rather than high density graphite and Shklyarevskii allegedly realized the scotch tape used to clean the graphite surface as possibly pulling off thinner graphite than the actual polishing technique. Microscopy revealed 10 graphene layer areas of very thin graphite on the scotch tape. But still no single layer graphene by Geim’s group in 2002.

    In 2002, while de Heer and Geim had focused on very thin graphite and the electronics thereof, RB Little (not familiar with the electronics but discovering new chemistry) discovered and proposed in 2002 that single layer graphene can form not only on surface of transition metals but also in free-standing thinnest of the air in the gas phase of electric arcs and laser plumes under suitable conditions given therein. While unraveling the plasma synthesis of single wall carbon nanotubes, RBL had determined in 2002 that single layer graphene can form in the gas phase of plasma under suitably different magnetic environment of the plasma and thermal quenching conditions relative to single wall carbon nanotube forming conditions. In 2002, RBL also proposed hydrogen and metal atoms can favor single layer graphene over single wall carbon nanotube by the hydrogen and metal atoms passivating the edge of the single layer graphene patch to counter it rolling into single wall carbon nanotube. This proposed synthesis of single layer graphene by RBL in 2002 was very remarkable because this free-standing plasma synthesis of single layer graphene was without a liquid or solid support (unlike Boehm, and the intercalators and the epitaxial growers) and very contrary to stability conditions (low temp) of Landau and Peierls. Even Geim’s microcleavage technique involved solid-liquid surfaces, but RBL plasma synthesis of single layer graphene was completely free-standing in the gas plasma state! This was the first ever realized formation of a free-standing atomic, crystalline flat layer in the gas phase, moreover in hot gas or plasma. This prediction was published in Journal of Cluster Science in 2003: “Mechanistic Aspects of Carbon Nanotube Formation”. The primary subject was carbon nanotube and the secondary subject was graphene, but the major premise (CNT) and minor premise (graphene) illustrated how this discovery in 2002 of single layer graphene arose out of determining the mechanism of single wall carbon nanotube formation. In 2002, while Geim and de Heer were limited to synthesizing thin graphite and 10 layered graphite, RBL explicitly gave correct formation conditions for true free-standing single layer graphite or graphene monolayers in 2002. This 2002 predicted plasma formation of single layer graphene by RBL has been later experimentally demonstrated by Frenklach and Rao and over 8 other research laboratories around the world. Both Frenklach and Rao demonstrate high quality of the plasma formed graphene with properties close to that of microcleaved graphene. Electric arc graphene has conductivity closes to microcleaved graphene!

    And of course Geim published measurements on mono crystalline graphite (“few atoms thick”) in Oct 2004 and de Heer on similar epitaxial graphite (“composed of typically three graphene sheets”) in Dec 2004.

    Sorry, but all I have to reason and communicate are the facts and the dates, which determine the real science! All else is nonsense!

  2. Report this comment

    sulihong said:

    The nobel prize has small error, many preface about graphene in macroworld application is not true.

    Mr.Harold Kroto(1996 noble prize) agree my viewpoint.

    The stable graphene depend on the boundary carbon bond. The graphene on the base maybe obtain big size, but its some property changed too. The graphene research is worthy of noble prize, but it exist small error,

    People could not synthesize the more than tens of micrometer suspended stable graphene.The carbon atom inside the graphene connect with three carbon atom by the bond, the boundary carbon atom only connect with two carbon atom. The C=C bond microstructure at boundary is different to the inside graphene.The outside C-C hexagon microstructure would be out of shape, the deform degree would change according to the radial. The molecular polarity and dispersion force that acted on the center carbon atom by the boundary C=C bond. It is key factor that the graphene exist stability in reality. the distance of dispersion force action is

    limited(because C=C bond stength is consent), the action strength would decrease greatly. In other words, the graphene special

    character would change greatly after its size increase.the graphene on the base maybe have big size, but its property have changed greatly than the micrometer size’s.

    If you are interested in my blog https://www.sciencenet.cn/u/sulihong/, you can find my viewpoint in Chinese. I sent the email to many scientists in this field.

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