Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Liquid method: pure graphene production

31.05.2010
Research could yield novel composites, touch-screen displays

In a development that could lead to novel carbon composites and touch-screen displays, researchers from Rice University and the Technion-Israel Institute of Technology today unveiled a new method for producing bulk quantities of one-atom-thick sheets of carbon called graphene.

The research is available online in the journal Nature Nanotechnology.

When stacked together, graphene sheets make graphite, which has been commonly used as pencil lead for hundreds of years. It wasn't until 2004 that stand-alone sheets of graphene were first characterized with modern nanotechnological instruments. Since then, graphene has come under intense scrutiny from materials scientists, in part because it is both ultrastrong and highly conductive.

"There are high-throughput methods for making graphene oxide, which is not as conductive as graphene, and there are low-throughput methods for making pure graphene," said lead co-author Matteo Pasquali, professor of chemical and biomolecular engineering and chemistry at Rice. "Our method yields very pure material, and it is based on bulk fluid-processing techniques that have long been used by the chemical industry."

Pasquali said the research team found it could dissolve graphite in chlorosulphonic acid, a common industrial solvent. The researchers had to devise new methods to measure the aggregation of the dissolved graphene flakes, but at the end the team was pleasantly surprised to find that the individual graphene layers in the graphite peeled apart spontaneously. The team was able to dissolve as much as two grams of graphene per liter of acid to produce solutions at least 10 times more concentrated than existing methods.

The researchers took advantage of novel cryogenic techniques for electron microscopy that allowed them to directly image the graphene sheets in the chlorosulfonic acid.

"We applied new methods that we had developed to directly image carbon nanotubes in acid," said co-author Yeshayahu "Ishi" Talmon, professor of chemical engineering at the Technion-Israel Institute of Technology. "This was no small feat considering the nature of the acid and the difficulty of specimen preparation and imaging."

Using the concentrated solutions of dissolved graphene, the scientists made transparent films that were electrically conductive. Such films could be useful in making touch screens that are less expensive than those used in today's smart phones. In addition, the researchers also produced liquid crystals.

"If you can make liquid crystals, you can spin fibers," said study co-author James Tour, Rice's T.T. and W.F. Chao Professor of Chemistry. "In liquid crystals, the individual sheets align themselves into domains, and having some measure of alignment allows you to flow the material through narrow openings to create fibers."

If the method proves useful for making graphene fibers in bulk, it could drive down the cost of the ultrastrong carbon composites used in the aerospace, automotive and construction industries.

The research was funded by the Air Force Office of Scientific Research, the Department of Energy, the Air Force Research Laboratory, the Welch Foundation, the U.S. Army Corps of Engineers and the USA-Israel Binational Science Foundation. Co-authors include Natnael Behabtu, Jay Lomeda, Micah Green, Amanda Higgenbotham, Alexander Sinitskii, Dmitry Kosynkin, Dmitri Tsentalovich and Nicholas Parra-Vasquez, all of Rice's Smalley Institute for Nanoscale Science and Technology; and Judith Schmidt, Ellina Kesselman and Yachin Cohen, all of the Technion-Israel Institute of Technology.

Jade Boyd | EurekAlert!
Further information:
http://www.rice.edu

More articles from Materials Sciences:

nachricht Serendipity uncovers borophene's potential
23.02.2017 | Northwestern University

nachricht Switched-on DNA
20.02.2017 | Arizona State University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>