Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Expanding the Degrees of Surface Freezing: Molecular ordering phenomenon found at interface between complex liquids and solids

Alexei Tkachenko, Htay Hlaing and Ben Ocko at an experimental end station at the NSLS.
Alexei Tkachenko, Htay Hlaing and Ben Ocko at an experimental end station at the NSLS.

Abstract:
As part of the quest to form perfectly smooth single-molecule layers of materials for advanced energy, electronic, and medical devices, researchers at the U.S. Department of Energy's Brookhaven National Laboratory have discovered that the molecules in thin films remain frozen at a temperature where the bulk material is molten. Thin molecular films have a range of applications extending from organic solar cells to biosensors, and understanding the fundamental aspects of these films could lead to improved devices.

Expanding the Degrees of Surface Freezing: Molecular ordering phenomenon found at interface between complex liquids and solids

Upton, NY | Posted on March 30th, 2011

The study, which appears in the April 1, 2011, edition of Physical Review Letters (now online at: link.aps.org/doi/10.1103/PhysRevLett.106.137801), is the first to directly observe "surface freezing" at the buried interface between bulk liquids and solid surfaces.

"In most materials, you expect that the surface will start to disorder and eventually melt at a temperature where the bulk remains solid," said Brookhaven physicist Ben Ocko, who collaborated on the research with scientists from the European Synchrotron Radiation Facility (ESRF), in France, and Bar-Ilan University, in Israel. "This is because the molecules on the outside are less confined than those packed in the deeper layers and much more able to move around. But surface freezing contradicts this basic idea. In surface freezing, the interfacial layers freeze before the bulk."

In the early 1990s, two independent teams (one at Brookhaven) made the first observation of surface freezing at the vapor interface of bulk alkanes, organic molecules similar to those in candle wax that contain only carbon and hydrogen atoms. Surface freezing has since been observed in a range of simple chain molecules and at various interfaces between them.

"The mechanics of surface freezing are still a mystery," said Bar Ilan scientist Moshe Deutsch. "It's puzzling why alkanes and their derivatives show this unusual effect, while virtually all other materials exhibit the opposite, surface melting, effect."

In the most recent study, the researchers discovered that surface freezing also occurs at the interface between a liquid and a solid surface. In a temperature-controlled environment at Brookhaven's National Synchrotron Light Source (NSLS, http://www.nsls.bnl.gov/) and the ESRF, the group made contact between a piece of highly polished sapphire and a puddle of liquid alkanol -- a long-chain alcohol. The researchers shot a beam of high-intensity x-rays through the interface and by measuring how the x-rays reflected off the sample, the group revealed that the alkanol molecules at the sapphire surface behave very differently from those in the bulk liquid.

According to ESRF scientist Diego Pontoni, "Surprisingly, the alkanol molecules form a perfect frozen monolayer at the sapphire interface at temperatures where the bulk is still liquid." At sufficiently high temperatures, about 30 degrees Celsius above the melting temperature of the bulk alkanol, the monolayer also melts.

The temperature range over which this frozen monolayer exists is about 10 times greater than what's observed at the liquid-vapor interfaces of similar materials. According to Alexei Tkachenko, a theoretical physicist who works at Brookhaven's Center for Functional Nanomaterials (CFN, www.bnl.gov/cfn/), "The temperature range of the surface-frozen layer and its temperature-dependent thickness can be described by a very simple model that we developed. What is remarkable is that the surface layer does not freeze abruptly as in the case of ice, or any other crystal. Rather, a smooth transition occurs over a temperature range of several degrees."

Said Ocko, "These films are better ordered and smoother than all other organic monolayer films created to date."

Moshe Deutsch added, "The results of this study and the theoretical framework which it provides may lead to new ideas on how to make defect-free, single molecule-thick films."

Funding for this work was provided by the U.S. Department of Energy's Office of Science and the U.S.-Israel Binational Science Foundation.

The Center for Functional Nanomaterials at Brookhaven National Laboratory is one of the five DOE Nanoscale Science Research Centers (NSRCs), premier national user facilities for interdisciplinary research at the nanoscale. Together the NSRCs comprise a suite of complementary facilities that provide researchers with state-of-the-art capabilities to fabricate, process, characterize and model nanoscale materials, and constitute the largest infrastructure investment of the National Nanotechnology Initiative. The NSRCs are located at DOE's Argonne, Brookhaven, Lawrence Berkeley, Oak Ridge and Sandia and Los Alamos national laboratories.

####

About Brookhaven National Laboratory
One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. Brookhaven is operated and managed for DOE's Office of Science by Brookhaven Science Associates, a limited-liability company founded by the Research Foundation of State University of New York on behalf of Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

Visit Brookhaven Lab's electronic newsroom for links, news archives, graphics, and more at www.bnl.gov/newsroom , or follow Brookhaven Lab on Twitter, twitter.com/BrookhavenLab .

For more information, please click here

Contacts:
Peter Genzer

(631) 344-3174
or
Karen McNulty Walsh

(631) 344-8350

Copyright © Brookhaven National Laboratory

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

Physics

Ultracold atom waves may shed light on rogue ocean killers: Rice quantum experiments probe underlying physics of rogue ocean waves April 27th, 2017

Geoffrey Beach: Drawn to explore magnetism: Materials researcher is working on the magnetic memory of the future April 25th, 2017

NIST physicists show ion pairs perform enhanced 'spooky action' March 30th, 2017

News and information

Ultracold atom waves may shed light on rogue ocean killers: Rice quantum experiments probe underlying physics of rogue ocean waves April 27th, 2017

Looking for the quantum frontier: Beyond classical computing without fault-tolerance? April 27th, 2017

Metal nanoparticles induced visible-light photocatalysis: Mechanisms, applications, ways of promoting catalytic activity and outlook April 27th, 2017

Arrowhead Pharmaceuticals to Webcast Fiscal 2017 Second Quarter Results April 27th, 2017

Affordable STM32 Cloud-Connectable Kit from STMicroelectronics Puts More Features On-Board for Fast and Flexible IoT-Device Development April 26th, 2017

Laboratories

Video captures bubble-blowing battery in action: Researchers propose how bubbles form, could lead to smaller lithium-air batteries April 26th, 2017

Thin films

Nanomechanics, Inc. Unveils New Product at ICMCTF Show April 25th: Nanoindentation experts will launch the new Gemini that measures the interaction of two objects that are sliding across each other – not merely making contact April 21st, 2017

Nanomechanics Inc. President Warren Oliver, PhD to Present at ICMCTF: Nanoindentation experts will discuss new testing system that measures the interaction of two objects that are sliding across each other – not merely making contact April 17th, 2017

Bio-inspired energy storage: A new light for solar power: Graphene-based electrode prototype, inspired by fern leaves, could be the answer to solar energy storage challenge April 2nd, 2017

Chip Technology

Geoffrey Beach: Drawn to explore magnetism: Materials researcher is working on the magnetic memory of the future April 25th, 2017

'Neuron-reading' nanowires could accelerate development of drugs for neurological diseases April 12th, 2017

Nanometrics to Announce First Quarter Financial Results on May 2, 2017 April 11th, 2017

AIM Photonics Presents Cutting-Edge Integrated Photonics Technology Developments to Packed House at OFC 2017, the Optical Networking and Communication Conference & Exhibition April 11th, 2017

Sensors

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

A Sensitive And Dynamic Tactile Sensor Read more from Asian Scientist Magazine at: https://www.asianscientist.com/2017/04/tech/tactile-3d-active-matrix-sensor/ April 18th, 2017

AIM Photonics Presents Cutting-Edge Integrated Photonics Technology Developments to Packed House at OFC 2017, the Optical Networking and Communication Conference & Exhibition April 11th, 2017

New technology could offer cheaper, faster food testing: Specialized droplets interact with bacteria and can be analyzed using a smartphone April 7th, 2017

Nanoelectronics

Researchers “iron out” graphene’s wrinkles: New technique produces highly conductive graphene wafers April 3rd, 2017

A big leap toward tinier lines: Self-assembly technique could lead to long-awaited, simple method for making smaller microchip patterns March 27th, 2017

Scientists discover new 'boat' form of promising semiconductor: GeSe Uncommon form attenuates semiconductor's band gap size March 23rd, 2017

UC researchers use gold coating to control luminescence of nanowires: University of Cincinnati physicists manipulate nanowire semiconductors in pursuit of making electronics smaller, faster and cheaper March 17th, 2017

Discoveries

Ultracold atom waves may shed light on rogue ocean killers: Rice quantum experiments probe underlying physics of rogue ocean waves April 27th, 2017

Looking for the quantum frontier: Beyond classical computing without fault-tolerance? April 27th, 2017

Metal nanoparticles induced visible-light photocatalysis: Mechanisms, applications, ways of promoting catalytic activity and outlook April 27th, 2017

Geoffrey Beach: Drawn to explore magnetism: Materials researcher is working on the magnetic memory of the future April 25th, 2017

Announcements

Ultracold atom waves may shed light on rogue ocean killers: Rice quantum experiments probe underlying physics of rogue ocean waves April 27th, 2017

Looking for the quantum frontier: Beyond classical computing without fault-tolerance? April 27th, 2017

Metal nanoparticles induced visible-light photocatalysis: Mechanisms, applications, ways of promoting catalytic activity and outlook April 27th, 2017

Arrowhead Pharmaceuticals to Webcast Fiscal 2017 Second Quarter Results April 27th, 2017

Energy

Using light to propel water : With new method, MIT engineers can control and separate fluids on a surface using only visible light April 25th, 2017

SUNY Polytechnic Institute Announces Total of 172 Teams Selected to Compete in Solar in Your Community Challenge: Teams from 40 states, plus Washington, DC, 2 Territories, and 4 American Indian Reservations, Will Deploy Solar in Underserved Communities April 20th, 2017

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

Shedding light on the absorption of light by titanium dioxide April 14th, 2017

Solar/Photovoltaic

SUNY Polytechnic Institute Announces Total of 172 Teams Selected to Compete in Solar in Your Community Challenge: Teams from 40 states, plus Washington, DC, 2 Territories, and 4 American Indian Reservations, Will Deploy Solar in Underserved Communities April 20th, 2017

Better living through pressure: Functional nanomaterials made easy April 19th, 2017

Shedding light on the absorption of light by titanium dioxide April 14th, 2017

Controlling forces between atoms, molecules, promising for ‘2-D hyperbolic’ materials April 4th, 2017

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