Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Tighter 'stitching' means better graphene, say scientists

Muller lab
False-color microscopy images show examples of graphene grown slowly, resulting in large patches with poor stitching, and graphene grown more quickly, resulting in smaller patches with tighter stitching and better performance.
Muller lab

False-color microscopy images show examples of graphene grown slowly, resulting in large patches with poor stitching, and graphene grown more quickly, resulting in smaller patches with tighter stitching and better performance.

Abstract:
Similar to how tighter stiches make for a better quality quilt, the "stitching" between individual crystals of graphene affects how well these carbon monolayers conduct electricity and retain their strength, Cornell researchers report.

Tighter 'stitching' means better graphene, say scientists

Ithaca, NY | Posted on June 4th, 2012

The quality of this "stitching" -- the boundaries at which graphene crystals grow together and form sheets -- is just as important as the size of the crystals themselves, which scientists had previously thought held the key to making better graphene.

The researchers, led by Jiwoong Park, assistant professor of chemistry and chemical biology and a member of the Kavli Institute at Cornell for Nanoscale Science, used advanced measurement and imaging techniques to make these claims, detailed online in the journal Science June 1.

Graphene is a single layer of carbon atoms, and materials scientists are engaged in a sort of arms race to manipulate and enhance its amazing properties -- tensile strength, high electrical conductance, and potential applications in photonics, photovoltaics and electronics. Cartoons depict graphene like a perfect atomic chicken wire stretching ad infinitum.

In reality, graphene is polycrystalline; it is grown via a process called chemical vapor deposition, in which small crystals, or grains, at random orientations grow by themselves and eventually join together in carbon-carbon bonds.

In earlier work published in Nature last January, the Cornell group had used electron microscopy to liken these graphene sheets to patchwork quilts -- each "patch" represented by the orientation of the graphene grains (and false colored to make them pretty).

They, along with other scientists, wondered how graphene's electrical properties would hold up based on its polycrystalline nature. Conventional wisdom and some prior indirect measurements had led scientists to surmise that growing graphene with larger crystals -- fewer patches -- might improve its properties.

The new work questions that dogma. The group compared how graphene performed based on different rates of growth via chemical vapor deposition; some they grew more slowly, and others, very quickly. They found that the more reactive, quick-growth graphene, with more patches, in certain ways performed better electronically than the slower growth graphene with larger patches.

As it turned out, faster growth led to tighter stitching between grains, which improved the graphene's performance, as opposed to larger grains that were more loosely held together.

"What's important here is that we need to promote the growth environment so that the grains stitch together well," Park said. "What we are showing is that grain boundaries were a main concern, but it could be that it doesn't matter. We are finding that it's probably OK."

Equal in importance to these observations were the complex techniques they used to make the measurements -- no easy task. A four-step electron beam lithography process, developed by Adam Tsen, an applied physics graduate student and the paper's first author, allowed the researchers to place electrodes on graphene, directly on top of a 10 nanometer-thick membrane substrate to measure electrical properties of single grain boundaries.

"Our technique sets a tone for how we can measure atomically thin materials in the future," Park added.

Collaborators led by David A. Muller, professor of applied and engineering physics and co-director of the Kavli Institute at Cornell for Nanoscale Science, used advanced transmission electron microscopy techniques to help Park's group image their graphene to show the differences in the grain sizes.

The work was supported by the Air Force Office of Scientific Research, and the National Science Foundation through the Cornell Center for Materials Research. Fabrication was performed at the Cornell NanoScale Science and Technology Facility.

####

For more information, please click here

Contacts:
Media Contact:
John Carberry
(607) 255-5353


Cornell Chronicle:
Anne Ju
(607) 255-9735

Copyright © Cornell University

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

Chains of nanogold – forged with atomic precision September 23rd, 2016

Tattoo therapy could ease chronic disease: Rice-made nanoparticles tested at Baylor College of Medicine may help control autoimmune diseases September 23rd, 2016

Nanotech Grants Options September 22nd, 2016

Coffee-infused foam removes lead from contaminated water September 21st, 2016

As You Sow’s Shareholder Inquiry on Nanomaterials Fought by Walgreens: Shareholder Proposal Addresses Recent Laboratory Tests Finding Harmful Nanomaterials in Walgreens’ Store Brand Infant Formula September 21st, 2016

Imaging

Oxford Instruments is ‘Bringing the Nanoworld Together’ in India once again - 22 - 23 November 2016 | IISc Bangalore September 21st, 2016

Bruker Introduces Complete Commercial AFM-Based SECM Solution: PeakForce SECM Mode Enables Previously Unobtainable Electrochemical Information September 20th, 2016

Oxford Instruments Asylum Research Announces New SurfRider Econo Board Probes for Routine AFM Measurements September 19th, 2016

Electron beam microscope directly writes nanoscale features in liquid with metal ink September 16th, 2016

Graphene/ Graphite

Graphene nanoribbons show promise for healing spinal injuries: Rice University scientists develop Texas-PEG to help knit severed, damaged spinal cords September 19th, 2016

Semiconducting inorganic double helix: New flexible semiconductor for electronics, solar technology and photo catalysis September 15th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Tattoo therapy could ease chronic disease: Rice-made nanoparticles tested at Baylor College of Medicine may help control autoimmune diseases September 23rd, 2016

PHENOMEN is a FET-Open Research Project aiming to lay the foundations a new information technology September 19th, 2016

NIST Patents Single-Photon Detector for Potential Encryption and Sensing Apps September 16th, 2016

Electron beam microscope directly writes nanoscale features in liquid with metal ink September 16th, 2016

Chip Technology

Mexican scientist in the Netherlands seeks to achieve data transmission ... speed of light September 20th, 2016

Towards Stable Propagation of Light in Nano-Photonic Fibers September 20th, 2016

PHENOMEN is a FET-Open Research Project aiming to lay the foundations a new information technology September 19th, 2016

NIST Patents Single-Photon Detector for Potential Encryption and Sensing Apps September 16th, 2016

Discoveries

Chains of nanogold – forged with atomic precision September 23rd, 2016

Tattoo therapy could ease chronic disease: Rice-made nanoparticles tested at Baylor College of Medicine may help control autoimmune diseases September 23rd, 2016

Speedy bacteria detector could help prevent foodborne illnesses September 21st, 2016

Coffee-infused foam removes lead from contaminated water September 21st, 2016

Materials/Metamaterials

Chains of nanogold – forged with atomic precision September 23rd, 2016

Coffee-infused foam removes lead from contaminated water September 21st, 2016

Containing our 'electromagnetic pollution': MXene can protect mobile devices from electromagnetic interference September 13th, 2016

New material to revolutionize water proofing September 12th, 2016

Announcements

Chains of nanogold – forged with atomic precision September 23rd, 2016

Tattoo therapy could ease chronic disease: Rice-made nanoparticles tested at Baylor College of Medicine may help control autoimmune diseases September 23rd, 2016

Nanotech Grants Options September 22nd, 2016

Coffee-infused foam removes lead from contaminated water September 21st, 2016

Tools

Oxford Instruments is ‘Bringing the Nanoworld Together’ in India once again - 22 - 23 November 2016 | IISc Bangalore September 21st, 2016

Bruker Introduces Complete Commercial AFM-Based SECM Solution: PeakForce SECM Mode Enables Previously Unobtainable Electrochemical Information September 20th, 2016

Oxford Instruments Asylum Research Announces New SurfRider Econo Board Probes for Routine AFM Measurements September 19th, 2016

Electron beam microscope directly writes nanoscale features in liquid with metal ink September 16th, 2016

Military

Tattoo therapy could ease chronic disease: Rice-made nanoparticles tested at Baylor College of Medicine may help control autoimmune diseases September 23rd, 2016

Nano-lipid particles from edible ginger could improve drug delivery for colon cancer, study finds September 8th, 2016

3-D graphene has promise for bio applications: Rice University-led team welds nanoscale sheets to form tough, porous material September 7th, 2016

Nanodiamonds in an instant: Rice University-led team morphs nanotubes into tougher carbon for spacecraft, satellites September 6th, 2016

Printing/Lithography/Inkjet/Inks/Bio-printing

Iran to hold intl. school on application of nanomaterials in medicine September 20th, 2016

Tailored probes for atomic force microscopes: 3-D laser lithography enhances microscope for studying nanostructures in biology and engineering/ publication in Applied Physics Letters August 11th, 2016

Smarter self-assembly opens new pathways for nanotechnology: Brookhaven Lab scientists discover a way to create billionth-of-a-meter structures that snap together in complex patterns with unprecedented efficiency August 9th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic