Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Graphene: What Can Go Wrong? New Studies Point to Wrinkles, Process Contaminants

Abstract:
Using a combination of sophisticated computer modeling and advanced materials analysis techniques at synchrotron laboratories, a research team led by the University at Buffalo (UB) and including the National Institute of Standards and Technology (NIST), the Molecular Foundry at Lawrence Berkeley National Laboratory and SEMATECH* has demonstrated how some relatively simple processing flaws can seriously degrade the otherwise near-magical electronic properties of graphene.

Graphene: What Can Go Wrong? New Studies Point to Wrinkles, Process Contaminants

Gaithersburg, MD | Posted on July 7th, 2011

Their new paper** demonstrates how both wrinkles in the graphene sheet and/or chance contaminants from processing—possibly hiding in those folds—disrupt and slow electron flow across the sheet. The results could be important for the design of commercial manufacturing processes that exploit the unique electrical properties of graphene. In the case of contaminant molecules at least, the paper also suggests that heating the graphene may be a simple solution.

Graphene, a nanostructured material that is essentially a one-atom thick sheet of carbon atoms arranged in a hexagonal pattern, is under intense study because of a combination of outstanding properties. It's extremely strong, conducts heat very well, and has high electrical conductivity while being flexible and transparent. Graphene's electrical properties, however, apparently depend a lot on flatness and purity.

Using X-rays, the UB team produced images that show the electron "cloud" lining the surface of graphene samples—the structure responsible for the high-speed transit of electrons across the sheet—and how wrinkles in the sheet distort the cloud and create bottlenecks. Spectrographic data showed anomalous "peaks" in some regions that also corresponded to distortions of the cloud. NIST researchers, using their dedicated materials science "beam line" at the National Synchrotron Light Source (NSLS),*** contributed a sensitive analysis of spectroscopic data confirming that these peaks were caused by chemical contaminants that adhered to the graphene during processing.

Significantly, the NIST synchrotron methods group was able to make detailed spectroscopic measurements of the graphene samples while heating them, and found that the mysterious peaks disappeared by the time the sample reached 150 degrees Celsius. This, according to Dan Fischer, leader of the NIST group, showed both that those particular disturbances in the electron cloud were due to contaminants, and that there is a way to get rid of them. "They're not chemical bound, they're just physically absorbed on the surface, and that's an important thing. You have a prescription for getting rid of them," Fischer said.

"When graphene was discovered, people were just so excited that it was such a good material that people really wanted to go with it and run as fast as possible," said Brian Schultz, one of three UB graduate students who were lead authors on the paper, "but what we're showing is that you really have to do some fundamental research before you understand how to process it and how to get it into electronics."

"This is the practical side of using graphene," agrees Fischer, "It has all these remarkable properties, but when you go to actually try to make something, maybe they stop working, and the question is: why and what do you do about it? These kinds of extremely sensitive, specialized techniques are part of that answer."

For more on the study, see the UB June 28, 2011, news announcement "Researchers Image Electron Clouds on the Surface of Graphene, Revealing How Folds in the Remarkable Material Can Harm Conductivity" at www.buffalo.edu/news/12673.

* SEMATECH is a nonprofit research consortium that advances the U.S. semiconductor industry.

** B.J. Schultz, C. J. Patridge, V. Lee, C. Jaye, P.S. Lysaght, C. Smith, J. Barnett, D.A. Fischer, D. Prendergast and S. Banerjee. Imaging local electronic corrugations and doped regions in graphene. Nature Communications. V2, 372. Published on-line June 28, 2011. doi:10.1038/ncomms1376.

*** The NSLS is located at the Brookhaven National Laboratory.

####

About NIST
The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

For more information, please click here

Contacts:
Michael Baum
301-975-2763

Copyright © NIST

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Researchers show what drives a novel, ordered assembly of alternating peptides February 20th, 2020

CEA-Leti and CEA-IRIG Demonstrate Quantum Integrated Circuit Combining Quantum Dot with Digital-Analog Circuits on CMOS Chip: Presentation at ISSCC 2020 Shows Role FD-SOI Can Play in Embedding Qubit Arrays with Classic Electronics to Build Large-Scale Quantum Silicon Processors February 20th, 2020

CEA-Leti Presents High-Performance Processor Breakthrough With Active Interposer and 3D Stacked Chiplets at ISSCC 2020 February 19th, 2020

New green technology from UMass Amherst generates electricity 'out of thin air' Renewable device could help mitigate climate change, power medical devices February 17th, 2020

Gold nanoclusters: new frontier for developing medication for treatment of Alzheimer's disease February 14th, 2020

Graphene/ Graphite

Does graphene cause or prevent the corrosion of copper? New study finally settles the debate: Scientists in Korea are first to observe an unprecedented way in which graphene forms a hybrid layer that prevents copper corrosion February 14th, 2020

Laboratories

KIST unveils the mystery of van der Waals magnets, a material for future semiconductors: Overcoming the limits of current magnetic materials, giving hope for development of next-generation semiconductors February 14th, 2020

MTU engineers examine lithium battery defects January 28th, 2020

SUNY Poly Professor Partners with Leading Institutions on NSF Award for Quantum Information Science Research: SUNY Poly Research Builds Upon Recent Quantum-related Research Initiatives and Workshops January 27th, 2020

Discoveries

Researchers show what drives a novel, ordered assembly of alternating peptides February 20th, 2020

New green technology from UMass Amherst generates electricity 'out of thin air' Renewable device could help mitigate climate change, power medical devices February 17th, 2020

Does graphene cause or prevent the corrosion of copper? New study finally settles the debate: Scientists in Korea are first to observe an unprecedented way in which graphene forms a hybrid layer that prevents copper corrosion February 14th, 2020

KIST unveils the mystery of van der Waals magnets, a material for future semiconductors: Overcoming the limits of current magnetic materials, giving hope for development of next-generation semiconductors February 14th, 2020

Announcements

CEA-Leti and CEA-IRIG Demonstrate Quantum Integrated Circuit Combining Quantum Dot with Digital-Analog Circuits on CMOS Chip: Presentation at ISSCC 2020 Shows Role FD-SOI Can Play in Embedding Qubit Arrays with Classic Electronics to Build Large-Scale Quantum Silicon Processors February 20th, 2020

CEA-Leti Presents High-Performance Processor Breakthrough With Active Interposer and 3D Stacked Chiplets at ISSCC 2020 February 19th, 2020

New green technology from UMass Amherst generates electricity 'out of thin air' Renewable device could help mitigate climate change, power medical devices February 17th, 2020

KIST unveils the mystery of van der Waals magnets, a material for future semiconductors: Overcoming the limits of current magnetic materials, giving hope for development of next-generation semiconductors February 14th, 2020

Research partnerships

KIST unveils the mystery of van der Waals magnets, a material for future semiconductors: Overcoming the limits of current magnetic materials, giving hope for development of next-generation semiconductors February 14th, 2020

A consensus statement establishes the protocols to assess and report stability of perovskite photovoltaic devices February 1st, 2020

New European Project to Fast-Track Adoption Of Cyber-Physical Systems (CPS) by SMEs: DigiFed to Demonstrate Potential of CPS Digital Technologies in Hardware Security, Human-Machine Interaction, and Autonomy for Small & Midsized Companies January 29th, 2020

The Wave of the Future: Researchers achieve first successful generation and detection of pure spin currents in antiferromagnetic materials January 29th, 2020

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project