Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New material breakthrough: Super-hard graphite cracks diamond

17.10.2003


It is hard to imagine that graphite, the soft "lead" of pencils, can be transformed into a form that competes in strength with its molecular cousin diamond. Using a diamond anvil to produce extreme pressures and the ultra-brilliant X-ray beams at the Advanced Photon Source in Illinois, scientists with the High-Pressure Collaborative Access Team (HPCAT)* have surmounted experimental obstacles to probe the changes that graphite undergoes to produce this unique, super-hard substance. The study is reported in the October 17, issue of Science.



"Researchers have speculated for years on the extreme conditions that might change the molecular structure of graphite into a super-hard form that rivals diamond," said Wendy Mao, the study’s lead author from the Carnegie Institution’s Geophysical Laboratory in Washington, D.C., and the University of Chicago. "This experiment is the first to determine quantitatively how the bonding in graphite changes under high-pressure conditions. Conventional methods limited our observations to surface studies of the material," she stated. "Now, with the super high-intensity X-rays of the Argonne facility and with our team’s technology to focus the entire beam to a small spot, we’ve been able to look at the material in the diamond-anvil cell while under high pressure. We’ve overcome the obstacles of the past," she concluded.

Graphite and diamond are both made of carbon. The geometric arrangement and spacing of the carbon atoms is what makes the materials differ in appearance and strength. The atoms in graphite are arranged in layers that are widely spaced. The atoms in diamond, on the other hand, are tightly linked producing a strongly bonded structure. The HPCAT scientists subjected graphite to pressures that are equivalent to 170,000 times the pressure at sea level ( 17 gigapascals). "We were able to see how the structure changed at the atomic level when the graphite was squeezed into the super-hard form," remarked co-author Dave Mao of Carnegie’s Geophysical Laboratory. "The graphite that resulted from our experiment was so hard that when we released the pressure we saw that it had actually cracked the diamond anvil."


The super-hard from of graphite opens the door to a myriad of applications in industry particularly as a structural component.



* HPCAT is made up of researchers from the Carnegie Institution’s Geophysical Laboratory, the High-Pressure Physics Group of the Lawrence Livermore National Laboratory, the High Pressure Science and Engineering Center of the University of Nevada, Las Vegas, and the University of Hawaii Institute of Geophysics and Planetology. Use of the HPCAT facility at Argonne National Laboratory for this work was funded by the Department of Energy, the National Nuclear Security Administration, the National Science Foundation, the Department of Defense, the W.M. Keck Foundation, and the Carnegie Institution of Washington.

The Carnegie Institution of Washington (www.CarnegieInstitution.org) has been a pioneering force in basic scientific research since 1902. It is a private, nonprofit organization with six research departments in the U.S.: Plant Biology, Global Ecology, The Observatories, Embryology, the Department of Terrestrial Magnetism, and the Geophysical Laboratory.

Wendy Mao | EurekAlert!
Further information:
http://www.CarnegieInstitution.org

More articles from Materials Sciences:

nachricht Researchers printed graphene-like materials with inkjet
18.08.2017 | Aalto University

nachricht Superconductivity research reveals potential new state of matter
17.08.2017 | DOE/Los Alamos National Laboratory

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>