Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Water sees right through graphene: Rice University, Rensselaer study reveals graphene enhances many materials, but leaves them wettable

Drops of water on a piece of silicon and on silicon covered by a layer of graphene show a minimal change in the contact angle between the water and the base material. Researchers at Rice University and Rensselaer Polytechnic Institute determined that when applied to most metals and silicon, a single layer of graphene is transparent to water. (Credit: Rahul Rao/Rensselaer Polytechnic Institute)
Drops of water on a piece of silicon and on silicon covered by a layer of graphene show a minimal change in the contact angle between the water and the base material. Researchers at Rice University and Rensselaer Polytechnic Institute determined that when applied to most metals and silicon, a single layer of graphene is transparent to water. (Credit: Rahul Rao/Rensselaer Polytechnic Institute)

Abstract:
Graphene is largely transparent to the eye and, as it turns out, largely transparent to water.

A new study by scientists at Rice University and Rensselaer Polytechnic Institute (RPI) has determined that gold, copper and silicon get just as wet when clad by a single continuous layer of graphene as they would without.

Water sees right through graphene: Rice University, Rensselaer study reveals graphene enhances many materials, but leaves them wettable

Houston, TX | Posted on January 23rd, 2012

The research, reported this week in the online edition of Nature Materials, is significant for scientists learning to fine-tune surface coatings for a variety of applications.

"The extreme thinness of graphene makes it a totally non-invasive coating," said Pulickel Ajayan, Rice's Benjamin M. and Mary Greenwood Anderson Professor in Mechanical Engineering and Materials Science and of chemistry. "A drop of water sitting on a surface 'sees through' the graphene layers and conforms to the wetting forces dictated by the surface beneath. It's quite an interesting phenomenon unseen in any other coatings and once again proves that graphene is really unique in many different ways." Ajayan is co-principal investigator of the study with Nikhil Koratkar, a professor of mechanical, aerospace and nuclear engineering at RPI.

A typical surface of graphite, the form of carbon most commonly known as pencil lead, should be hydrophobic, Ajayan said. But in the present study, the researchers found to their surprise that a single-atom-thick layer of the carbon lattice presents a negligible barrier between water and a hydrophilic - water-loving - surface. Piling on more layers reduces wetting; at about six layers, graphene essentially becomes graphite.

An interesting aspect of the study, Ajayan said, may be the ability to change such surface properties as conductivity while retaining wetting characteristics. Because pure graphene is highly conductive, the discovery could lead to a new class of conductive, yet impermeable, surface coatings, he said.

The caveat is that wetting transparency was observed only on surfaces (most metals and silicon) where interaction with water is dominated by weak van der Waals forces, and not for materials like glass, where wettability is dominated by strong chemical bonding, the team reported.

But such applications as condensation heat transfer -- integral to heating, cooling, dehumidifying, water harvesting and many industrial processes -- may benefit greatly from the discovery, according to the paper. Copper is commonly used for its high thermal conductivity, but it corrodes easily. The team coated a copper sample with a single layer of graphene and found the subnanometer barrier protected the copper from oxidation with no impact on its interaction with water; in fact, it enhanced the copper's thermal effectiveness by 30 to 40 percent.

"The finding is interesting from a fundamental point of view as well as for practical uses," Ajayan said. "Graphene could be one of a kind as a coating, allowing the intrinsic physical nature of surfaces, such as wetting and optical properties, to be retained while altering other specific functionalities like conductivity."

The paper's co-authors are Rice graduate student Hemtej Gullapalli, RPI graduate students Javad Rafiee, Xi Mi, Abhay Thomas and Fazel Yavari, and Yunfeng Shi, an assistant professor of materials science and engineering at RPI.

The Advanced Energy Consortium, National Science Foundation and the Office of Naval Research graphene MURI program funded the research.

####

About Rice University
Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation's top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is known for its "unconventional wisdom." With 3,708 undergraduates and 2,374 graduate students, Rice's undergraduate student-to-faculty ratio is less than 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice has been ranked No. 1 for best quality of life multiple times by the Princeton Review and No. 4 for "best value" among private universities by Kiplinger's Personal Finance. To read "What they're saying about Rice," go to www.rice.edu/nationalmedia/Rice.pdf.

For more information, please click here

Contacts:
David Ruth
713-348-6327


Mike Williams
713-348-6728

Copyright © Rice 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 Links

Read the abstract at:

Related News Press

News and information

Remote-control shoots laser at nano-gold to turn on cancer-killing immune cells April 20th, 2018

New qubit now works without breaks: A universal design for superconducting qubits has been created April 19th, 2018

Observing biological nanotransporters: Chemistry April 19th, 2018

Salt boosts creation of 2-D materials: Rice University scientists show how salt lowers reaction temperatures to make novel materials April 18th, 2018

Individual impurity atoms detectable in graphene April 18th, 2018

Chemistry

Salt boosts creation of 2-D materials: Rice University scientists show how salt lowers reaction temperatures to make novel materials April 18th, 2018

Phononic SEIRA -- enhancing light-molecule interactions via crystal lattice vibrations April 10th, 2018

Graphene/ Graphite

Individual impurity atoms detectable in graphene April 18th, 2018

High-speed and on-silicon-chip graphene blackbody emitters: Integrated light emitters for optical communications April 5th, 2018

This Wired Wallpaper Could Turn Your Whole House Into A Fire Alarm April 2nd, 2018

Govt.-Legislation/Regulation/Funding/Policy

Remote-control shoots laser at nano-gold to turn on cancer-killing immune cells April 20th, 2018

Salt boosts creation of 2-D materials: Rice University scientists show how salt lowers reaction temperatures to make novel materials April 18th, 2018

Quantum shift shows itself in coupled light and matter: Rice University scientists corral, quantify subtle movement in condensed matter system April 16th, 2018

When superconductivity disappears in the core of a quantum tube: By replacing the electrons with ultra-cold atoms, a group of physicists has created a perfectly clean material, unveiling new states of matter at the quantum level April 16th, 2018

Chip Technology

New qubit now works without breaks: A universal design for superconducting qubits has been created April 19th, 2018

Salt boosts creation of 2-D materials: Rice University scientists show how salt lowers reaction temperatures to make novel materials April 18th, 2018

When superconductivity disappears in the core of a quantum tube: By replacing the electrons with ultra-cold atoms, a group of physicists has created a perfectly clean material, unveiling new states of matter at the quantum level April 16th, 2018

Nanometrics to Announce First Quarter Financial Results on May 1, 2018 April 10th, 2018

Discoveries

Remote-control shoots laser at nano-gold to turn on cancer-killing immune cells April 20th, 2018

New qubit now works without breaks: A universal design for superconducting qubits has been created April 19th, 2018

Observing biological nanotransporters: Chemistry April 19th, 2018

Salt boosts creation of 2-D materials: Rice University scientists show how salt lowers reaction temperatures to make novel materials April 18th, 2018

Materials/Metamaterials

Salt boosts creation of 2-D materials: Rice University scientists show how salt lowers reaction temperatures to make novel materials April 18th, 2018

Individual impurity atoms detectable in graphene April 18th, 2018

Psst! A whispering gallery for light boosts solar cells April 14th, 2018

Artificial intelligence accelerates discovery of metallic glass: Machine learning algorithms pinpoint new materials 200 times faster than previously possible April 13th, 2018

Announcements

Remote-control shoots laser at nano-gold to turn on cancer-killing immune cells April 20th, 2018

New qubit now works without breaks: A universal design for superconducting qubits has been created April 19th, 2018

Observing biological nanotransporters: Chemistry April 19th, 2018

Salt boosts creation of 2-D materials: Rice University scientists show how salt lowers reaction temperatures to make novel materials April 18th, 2018

Military

Quantum shift shows itself in coupled light and matter: Rice University scientists corral, quantify subtle movement in condensed matter system April 16th, 2018

New 4-D printer could reshape the world we live in March 20th, 2018

Imaging technique pulls plasmon data together: Rice University scientists' hyperspectral method analyzes many plasmonic nanoparticles in an instant March 16th, 2018

Flat gallium joins roster of new 2-D materials: Rice University, Indian Institute of Science introduce gallenene March 12th, 2018

Research partnerships

New qubit now works without breaks: A universal design for superconducting qubits has been created April 19th, 2018

Salt boosts creation of 2-D materials: Rice University scientists show how salt lowers reaction temperatures to make novel materials April 18th, 2018

Psst! A whispering gallery for light boosts solar cells April 14th, 2018

Artificial intelligence accelerates discovery of metallic glass: Machine learning algorithms pinpoint new materials 200 times faster than previously possible April 13th, 2018

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