Navigation Links
Researchers discover new properties of World's thinnest material
Date:6/14/2010

Graphene oxide, a single-atomic-layered material made by reacting graphite powders with strong oxidizing agents, has attracted a lot of interest from scientists because of its ability to easily convert to graphene a hotly studied material that scientists believe could be used to produce low-cost carbon-based transparent and flexible electronics.

But to Jiaxing Huang, assistant professor of materials science and engineering, and his research group at the McCormick School of Engineering and Applied Science at Northwestern University, graphene oxide itself is even more interesting. Huang and his group have studied the material for years and have discovered how to assemble these soft sheets like floating water lilies pads. They also used a camera flash to turn them into graphene, and invented a fluorescence quenching technique to make them visible under microscopes.

Now, working with Kenneth R. Shull, professor of materials science and engineering, they have discovered that graphene oxide sheets behave like surfactants, the chemicals in soap and shampoo that make stains disperse in water. The team's results are published online in the Journal of the American Chemical Society.

Graphene oxide has been known in the scientific world for more than a century and was largely described as hydrophilic, or attracted to water. But Huang and his research group thought that graphene oxide should be amphiphilic, a property of surfactants that can both attracts and repels water, because part of the graphene oxide structure is actually water repelling.

"We view graphene oxide as a soft material," Huang says. "For example, it is essentially two-dimensional polymers composed of carbon, hydrogen and oxygen. They are also colloidal particles with very exotic shapes."

To test their hypothesis, Huang and his group put graphene oxide in carbonated water. They found that the sheets can hitchhike onto the rising bubbles to reach the water surface just like a surfactant would do. Next they found that graphite oxide can disperse oil droplets in water just like a surfactant would.

This new insight into a fundamental property of the material, according to Huang, is important for understanding how graphene oxide is processed and handled. It could lead to new applications for the material.

Its surfactant properties mean it could be used as a dispersing agent for insoluble materials, like carbon nanotubes. Common surfactants are non-conducting, so when used as a dispersing agent for conducting materials, they need to be removed from the material. Graphite oxide, which turns into conducting graphene through heating, would actually help conductivity.

The surfactant behavior inspired another exciting discovery that water surface can act as a filter for separating graphene oxide sheets by size.

"The smaller the sheet, the more water-liking it becomes, so eventually it will sink into water," Huang says. This effect makes it easier to harvest large sheets of graphene oxide, which are more useful for graphene device fabrication.


'/>"/>

Contact: Megan Fellman
fellman@northwestern.edu
847-491-3115
Northwestern University
Source:Eurekalert

Related biology technology :

1. Researchers improve ability to write and store information on electronic devices
2. Long-awaited international ethical guidelines for biobank researchers
3. CU researchers shed light on light-emitting nanodevice
4. Stevens researchers provide new information about mass spectrometry
5. Researchers measure carbon nanotube interaction
6. Researchers underscore limitations of genetic ancestry tests
7. ASU researchers improve memory devices using nanotech
8. UD researchers race ahead with latest spintronics achievement
9. Researchers outline structure of largest nonvirus particle ever crystallized
10. Ames Laboratory researchers solve fuel-cell membrane structure conundrum
11. Researchers use magnetism to target cells to animal arteries
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/22/2017)... ... 2017 , ... RURO, Inc., a leading LIMS, RFID, and ... update to the Limfinity® framework. , LimitLIS® and other RURO solutions based on ... customers among labs and other businesses. Limfinity® 6.5 adds new features and improvements ...
(Date:6/20/2017)... ... June 20, 2017 , ... CTNext ... of directors has formed a Higher Education Entrepreneurship Advisory Committee to implement the ... presidents and other high-ranking representatives from 35 higher education institutions across the state ...
(Date:6/20/2017)... ... 20, 2017 , ... HorizonScan is providing food and ingredient ... likely threat to their products at the annual IFT conference in Las Vegas, ... expo attracts over 20,000 attendees representing food science professionals from over 90 countries ...
(Date:6/20/2017)... ... 2017 , ... National executive search firm, Slone Partners, announces ... and biomarker expertise, as VP of Scientific Affairs at Cambridge Biomedical. , ... development and sample testing services. The organization acts as a leading provider of ...
Breaking Biology Technology:
(Date:4/5/2017)... , April 5, 2017  The Allen Institute ... Allen Cell Explorer: a one-of-a-kind portal and dynamic digital ... 3D imaging data, the first application of deep learning ... human stem cell lines and a growing suite of ... platform for these and future publicly available resources created ...
(Date:4/5/2017)... 4, 2017 KEY FINDINGS The ... at a CAGR of 25.76% during the forecast period ... primary factor for the growth of the stem cell ... MARKET INSIGHTS The global stem cell market ... and geography. The stem cell market of the product ...
(Date:4/3/2017)... , April 3, 2017  Data captured ... engineering platform, detected a statistically significant association ... prior to treatment and objective response of ... potential to predict whether cancer patients will ... treatment, as well as to improve both pre-infusion ...
Breaking Biology News(10 mins):