Navigation Links
UT Austin researchers grow large graphene crystals that have exceptional electrical properties

AUSTIN, Texas When it comes to the growth of graphene an ultrathin, ultrastrong, all-carbon material it is survival of the fittest, according to researchers at The University of Texas at Austin.

The team used surface oxygen to grow centimeter-size single graphene crystals on copper. The crystals were about 10,000 times as large as the largest crystals from only four years ago. Very large single crystals have exceptional electrical properties.

"The game we play is that we want nucleation (the growth of tiny 'crystal seeds') to occur, but we also want to harness and control how many of these tiny nuclei there are, and which will grow larger," said Rodney S. Ruoff, professor in the Cockrell School of Engineering. "Oxygen at the right surface concentration means only a few nuclei grow, and winners can grow into very large crystals."

The team led by postdoctoral fellow Yufeng Hao and Ruoff of the Department of Mechanical Engineering and the Materials Science and Engineering Program, along with Luigi Colombo, a material scientist with Texas Instruments worked for three years on the graphene growth method. The team's paper, "The Role of Surface Oxygen in the Growth of Large Single-Crystal Graphene on Copper," is featured on the cover of the Nov. 8, 2013, issue of Science.

One of the world's strongest materials, graphene is flexible and has high electrical and thermal conductivity that makes it a promising material for flexible electronics, solar cells, batteries and high-speed transistors. The team's understanding of how graphene growth is influenced by differing amounts of surface oxygen is a major step toward improved high-quality graphene films at industrial scale.

The team's method "is a fundamental breakthrough, which will lead to growth of high-quality and large area graphene film," said Sanjay Banerjee, who heads the Cockrell School's South West Academy of Nanoelectronics (SWAN). "By increasing the single-crystal domain sizes, the electronic transport properties will be dramatically improved and lead to new applications in flexible electronics."

Graphene has always been grown in a polycrystalline form, that is, it is composed of many crystals that are joined together with irregular chemical bonding at the boundaries between crystals ("grain boundaries"), something like a patch-work quilt. Large single-crystal graphene is of great interest because the grain boundaries in polycrystalline material have defects, and eliminating such defects makes for a better material.

By controlling the concentration of surface oxygen, the researchers could increase the crystal size from a millimeter to a centimeter. Rather than hexagon-shaped and smaller crystals, the addition of the right amount of surface oxygen produced much larger single crystals with multibranched edges, similar to a snowflake.

"In the long run it might be possible to achieve meter-length single crystals," Ruoff said. "This has been possible with other materials, such as silicon and quartz. Even a centimeter crystal size if the grain boundaries are not too defective is extremely significant."

"We can start to think of this material's potential use in airplanes and in other structural applications if it proves to be exceptionally strong at length scales like parts of an airplane wing, and so on," he said.

Another major finding by the team was that the "carrier mobility" of electrons (how fast the electrons move) in graphene films grown in the presence of surface oxygen is exceptionally high. This is important because the speed at which the charge carriers move is important for many electronic devices the higher the speed, the faster the device can perform.

Yufeng Hao says he thinks the knowledge gained in this study could prove useful to industry.

"The high quality of the graphene grown by our method will likely be developed further by industry, and that will eventually allow devices to be faster and more efficient," Hao said.

Single-crystal films can also be used for the evaluation and development of new types of devices that call for a larger scale than could be achieved before, added Colombo.

"At this time, there are no other reported techniques that can provide high quality transferrable films," Colombo said. "The material we were able to grow will be much more uniform in its properties than a polycrystalline film."


Contact: Sandra Zaragoza
University of Texas at Austin

Related biology technology :

1. Nanoelectronics Center at UT Austin receives $7.8 million grant
2. CEM President and CEO Delivers Commencement Address at the 2012 University of Texas at Austin Chemistry and Biochemistry Department Graduation
3. Life Technologies Plant in Austin, Texas Named One of IndustryWeeks Top Ten Best Plants for 2011
4. Researchers at Penn add another tool in their directed assembly toolkit
5. York researchers discover important mechanism behind nanoparticle reactivity
6. Researchers discover how retinal neurons claim the best brain connections
7. Researchers measure flow from a nanoscale fluid jet
8. Researchers advance scheme to design seamless integrated circuits etched on graphene
9. Harvard researchers, pharma experts offer recommendations to expand access to clinical trial data
10. Virginia Tech researchers publish study on jellyfish energy consumption that will improve bio-inspired robotic designs for Navy
11. Spanish researchers sequence non-infiltrating bladder cancer exome
Post Your Comments:
Related Image:
UT Austin researchers grow large graphene crystals that have exceptional electrical properties
(Date:11/24/2015)... ... 2015 , ... Copper is an essential micronutrient that all ... copper is also toxic to cells. With a $1.3 million award from the ... a systematic study of copper in the bacteria Pseudomonas aeruginosa (P. aeruginosa), a ...
(Date:11/24/2015)... -- Clintrax Global, Inc., a worldwide provider of clinical research services headquartered ... the company has set a new quarterly earnings record in Q3 ... posted for Q3 of 2014 to Q3 of 2015.   ... , with the establishment of an Asia-Pacific ... United Kingdom and Mexico , with ...
(Date:11/24/2015)... ... November 24, 2015 , ... The Academy of Model ... Group (SIG), MultiGP, also known as Multirotor Grand Prix, to represent the First–Person View ... years. Many AMA members have embraced this type of racing and several new model ...
(Date:11/24/2015)... -- Tikcro Technologies Ltd. (OTCQB: TIKRF) today announced that its Annual General Meeting ... Israel time, at the law offices of ... th Floor, Tel Aviv, Israel . ... Izhak Tamir to the Board of Directors; , election of ... approval of an amendment to certain terms of options granted to our ...
Breaking Biology Technology:
(Date:11/4/2015)... ALBANY, New York , November 4, 2015 /PRNewswire/ ... According to a new market report published by Transparency ... Size, Share, Growth, Trends and Forecast 2015 - 2022", ... value of US$ 30.3 bn by 2022. The market ... during the forecast period from 2015 to 2022. Rising ...
(Date:10/29/2015)... Daon, a global leader in mobile biometric ... new version of its IdentityX Platform , IdentityX ... have already installed IdentityX v4.0 and are ... FIDO UAF certified server component as an option ... features. These customers include some of the largest and ...
(Date:10/29/2015)... , Oct. 29, 2015 Today, ... a partnership with 2XU, a global leader in ... a smart hat with advanced bio-sensing technology. The ... athletes to monitor key biometrics to improve overall ... partnership, the two companies will bring together the most ...
Breaking Biology News(10 mins):