Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A new way to make sheets of graphene

26.05.2014

Technique might enable advances in display screens, solar cells, or other devices

Graphene's promise as a material for new kinds of electronic devices, among other uses, has led researchers around the world to study the material in search of new applications. But one of the biggest limitations to wider use of the strong, lightweight, highly conductive material has been the hurdle of fabrication on an industrial scale.

Initial work with the carbon material, which forms an atomic-scale mesh and is just a single atom thick, has relied on the use of tiny flakes, typically obtained by quickly removing a piece of sticky tape from a block of graphite — a low-tech system that does not lend itself to manufacturing. Since then, focus has shifted to making graphene films on metal foil, but researchers have faced difficulties in transferring the graphene from the foil to useful substrates.

Now researchers at MIT and the University of Michigan have come up with a way of producing graphene, in a process that lends itself to scaling up, by making graphene directly on materials such as large sheets of glass. The process is described, in a paper published this week in the journal Scientific Reports, by a team of nine researchers led by A. John Hart of MIT. Lead authors of the paper are Dan McNerny, a former MIT postdoc who is now at Michigan, and Viswanath Balakrishnan, a former MIT postdoc who is now at the Indian Institute of Technology.

... more about:
»Industries »copper »damage »deposit »glass »graphene

Currently, most methods of making graphene first grow the material on a film of metal, such as nickel or copper, says Hart, the Mitsui Career Development Associate Professor of Mechanical Engineering. "To make it useful, you have to get it off the metal and onto a substrate, such as a silicon wafer or a polymer sheet, or something larger like a sheet of glass," he says. "But the process of transferring it has become much more frustrating than the process of growing the graphene itself, and can damage and contaminate the graphene."

The new work, Hart says, still uses a metal film as the template — but instead of making graphene only on top of the metal film, it makes graphene on both the film's top and bottom. The substrate in this case is silicon dioxide, a form of glass, with a film of nickel on top of it.

Using chemical vapor deposition (CVD) to deposit a graphene layer on top of the nickel film, Hart says, yields "not only graphene on top [of the nickel layer], but also on the bottom." The nickel film can then be peeled away, leaving just the graphene on top of the nonmetallic substrate.

This way, there's no need for a separate process to attach the graphene to the intended substrate — whether it's a large plate of glass for a display screen, or a thin, flexible material that could be used as the basis for a lightweight, portable solar cell, for example. "You do the CVD on the substrate, and, using our method, the graphene stays behind on the substrate," Hart says.

In addition to the researchers at Michigan, where Hart previously taught, the work was done in collaboration with a large glass manufacturer, Guardian Industries. "To meet their manufacturing needs, it must be very scalable," Hart says. The company currently uses a float process, where glass moves along at a speed of several meters per minute in facilities that produce hundreds of tons of glass every day. "We were inspired by the need to develop a scalable manufacturing process that could produce graphene directly on a glass substrate," Hart says.

The work is still in an early stage; Hart cautions that "we still need to improve the uniformity and the quality of the graphene to make it useful." But the potential is great, he suggests: "The ability to produce graphene directly on nonmetal substrates could be used for large-format displays and touch screens, and for 'smart' windows that have integrated devices like heaters and sensors."

Hart adds that the approach could also be used for small-scale applications, such as integrated circuits on silicon wafers, if graphene can be synthesized at lower temperatures than were used in the present study.

"This new process is based on an understanding of graphene growth in concert with the mechanics of the nickel film," he says. "We've shown this mechanism can work. Now it's a matter of improving the attributes needed to produce a high-performance graphene coating."

###

The work was supported by Guardian Industries, the National Science Foundation, and the Air Force Office of Scientific Research.

Written by David Chandler, MIT News Office

Andrew Carleen | Eurek Alert!
Further information:
http://www.mit.edu

Further reports about: Industries copper damage deposit glass graphene

More articles from Materials Sciences:

nachricht Electrifying Research: Piezoelectric Effects for the Suppression of Material Stresses
30.03.2015 | Austrian Science Fund FWF

nachricht Recipe for antibacterial plastic: Plastic plus egg whites
30.03.2015 | University of Georgia

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Experiment Provides the Best Look Yet at 'Warm Dense Matter' at Cores of Giant Planets

In an experiment at the Department of Energy's SLAC National Accelerator Laboratory, scientists precisely measured the temperature and structure of aluminum as...

Im Focus: Energy-autonomous and wireless monitoring protects marine gearboxes

The IPH presents a solution at HANNOVER MESSE 2015 to make ship traffic more reliable while decreasing the maintenance costs at the same time. In cooperation with project partners, the research institute from Hannover, Germany, has developed a sensor system which continuously monitors the condition of the marine gearbox, thus preventing breakdowns. Special feature: the monitoring system works wirelessly and energy-autonomously. The required electrical power is generated where it is needed – directly at the sensor.

As well as cars need to be certified regularly (in Germany by the TÜV – Technical Inspection Association), ships need to be inspected – if the powertrain stops...

Im Focus: 3-D satellite, GPS earthquake maps isolate impacts in real time

Method produced by UI researcher could improve reaction time to deadly, expensive quakes

When an earthquake hits, the faster first responders can get to an impacted area, the more likely infrastructure--and lives--can be saved.

Im Focus: Atlantic Ocean overturning found to slow down already today

The Atlantic overturning is one of Earth’s most important heat transport systems, pumping warm water northwards and cold water southwards. Also known as the Gulf Stream system, it is responsible for the mild climate in northwestern Europe. 

Scientists now found evidence for a slowdown of the overturning – multiple lines of observation suggest that in recent decades, the current system has been...

Im Focus: Robot inspects concrete garage floors and bridge roadways for damage

Because they are regularly subjected to heavy vehicle traffic, emissions, moisture and salt, above- and underground parking garages, as well as bridges, frequently experience large areas of corrosion. Most inspection systems to date have only been capable of inspecting smaller surface areas.

From April 13 to April 17 at the Hannover Messe (hall 2, exhibit booth C16), engineers from the Fraunhofer Institute for Nondestructive Testing IZFP will be...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Conference On Regenerative Medicine 2015: Registration And Abstract Submission Now Open

25.03.2015 | Event News

University presidents from all over the world meet in Hamburg

19.03.2015 | Event News

10. CeBiTec Symposium zum Big Data-Problem

17.03.2015 | Event News

 
Latest News

Researchers discover how body's good fat tissue communicates with brain

30.03.2015 | Life Sciences

For drivers with telescopic lenses, driving experience and training affect road test results

30.03.2015 | Health and Medicine

Climate change does not cause extreme winters

30.03.2015 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>