Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Scientists use molecular layers to study nanoscale heat transfer

Abstract:
Scientific research has provided us with a fundamental understanding of how light (via photons) and electricity (via electrons) move within and between materials at the micrometer or nanometer levels, making possible a wide variety of miniature devices such as transistors, optical sensors and microelectromechanical systems (MEMS). However, man's knowledge of micro- and nanoscale heat flow is rudimentary at best. Now, a research team at the University of Illinois at Urbana-Champaign (UIUC) has developed a novel system for examining and measuring nanoscale thermal conductance at the interface between two materials. With further refinement, the scientists believe their advance may one day provide data for applications such as harvesting electricity from waste heat, better cooling of microelectronic devices and "heat-seeking" targeting of disease cells by hyperthermal (above normal body temperature) therapeutics.

Scientists use molecular layers to study nanoscale heat transfer

College Park, MD | Posted on October 28th, 2012

The team's findings will be presented by Mark Losego, formerly a post-doctoral fellow at UIUC and now a research assistant professor in chemical and biomolecular engineering at North Carolina State University, during the AVS 59th International Symposium and Exhibition, held Oct. 28-Nov. 2, 2012, in Tampa, Fla.

At the nanoscale, thermal properties are the result of vibrations between neighboring atoms. Bonds between atoms carry these vibrations similar to an oscillating spring. The UIUC team developed a technique for studying the effects of these bonds on heat transport across an interface between two different materials. "We wanted a system where we could observe, analyze and quantify thermal flow across an interface with atomic-level precision," Losego says.

The system starts with a substrate base of quartz crystal, upon which the researchers place molecular chains that are 12 carbon atoms long. At the base of each chain is a chemical "cap" that covalently bonds to quartz. The attraction of these caps to the substrate spontaneously aligns all of the carbon chains into an ordered array of molecules known as a self-assembled monolayer (SAM). At the opposite end of each carbon chain is a different kind of cap, either a thiol (sulfur and hydrogen) group that bonds strongly to metals or a methyl group (carbon and hydrogen) that bonds weakly.

"We then make use of a viscoelastic silicone stamp to 'transfer print' gold layers onto the SAM surface," Losego explains. "This process is similar to transferring a decal onto a T-shirt where the gold film is the 'decal' attached to the silicone stamp 'backing'. When we slowly peel away the silicone, we leave the gold layer on top of the SAM."

It is at the interface between the gold film and the SAM, Losego says, where nanoscale heat flow is characterized. "Changing the chemical groups that are in contact with the gold layer allows us to see how different bonds affect heat transfer," he adds.

Combined with an ultrafast laser technique capable of monitoring temperature decay (or heat loss) with picosecond (trillionth of a second) resolution, the UIUC researchers are able to use their experimental system to evaluate heat flow at the atomic scale. "We heat the gold layer attached to the monolayer and can monitor temperature decay with time," Losego explains. "Concurrently, we observe oscillations in the gold film that indicate the strength of the bonds at the gold-SAM junction. Using these measurements we are able to independently verify that strong bonds [fast-decaying oscillations] have rapid heat transfer while weak bonds [slowly decaying oscillations] have slower heat transfer."

The researchers plan to refine their nanoscale thermal measurement system and develop theoretical calculations to better interpret the data it produces.

MORE INFORMATION ABOUT THE AVS 59th INTERNATIONAL SYMPOSIUM & EXHIBITION

The Tampa Convention Center is located along the Riverwalk in the heart of downtown Tampa at 333 S. Franklin St., Tampa, Florida, 33602.

ABOUT AVS

Founded in 1953, AVS is a not-for-profit professional society that promotes communication between academia, government laboratories, and industry for the purpose of sharing research and development findings over a broad range of technologically relevant topics. Its symposia and journals provide an important forum for the dissemination of information in many areas of science and technology, enabling a critical gateway for the rapid insertion of scientific breakthroughs into manufacturing realities.

####

For more information, please click here

Contacts:
Catherine Meyers
301-209-3088

Copyright © American Institute of Physics (AIP)

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

Main meeting website:

Technical Program:

Housing and Travel Information:

Related News Press

News and information

Spin current detection in quantum materials unlocks potential for alternative electronics October 15th, 2017

Quantum manipulation power for quantum information processing gets a boost: Improving the efficiency of quantum heat engines involves reducing the number of photons in a cavity, ultimately impacting quantum manipulation power October 14th, 2017

Injecting electrons jolts 2-D structure into new atomic pattern: Berkeley Lab study is first to show potential of energy-efficient next-gen electronic memory October 13th, 2017

The secret to improving liquid crystal's mechanical performance: Better lubricating properties of lamellar liquid crystals could stem from changing the mobility of their structural dislocations by adding nanoparticles October 13th, 2017

Rice U. lab surprised by ultraflat magnets: Researchers create atom-thick alloys with unanticipated magnetic properties October 13th, 2017

Physics

The secret to improving liquid crystal's mechanical performance: Better lubricating properties of lamellar liquid crystals could stem from changing the mobility of their structural dislocations by adding nanoparticles October 13th, 2017

What can be discovered at the junction of physics and chemistry October 6th, 2017

Energy against the current on a quantum scale, without contradicting the laws of physics: A piece of research in which the UPV/EHU-University of the Basque Country has participated confirms that merely observing a flow of energy or particles can change its direction October 6th, 2017

Tungsten offers nano-interconnects a path of least resistance: Crystalline tungsten shows insight and promise in addressing the challenges of electrical interconnects that have high resistivity at the nanoscale October 4th, 2017

Chemistry

What can be discovered at the junction of physics and chemistry October 6th, 2017

Nanomedicine

Arrowhead Pharmaceuticals to Present Preclinical Data on ARO-AAT at The Liver Meeting(R) October 10th, 2017

Arrowhead to Present at Chardan Gene Therapy Conference October 3rd, 2017

'CRISPR-Gold' fixes Duchenne muscular dystrophy mutation in mice October 3rd, 2017

Nonviral CRISPR Delivery a Success October 2nd, 2017

Discoveries

Rice U. study: Vibrating nanoparticles interact: Placing nanodisks in groups can change their vibrational frequencies October 16th, 2017

Spin current detection in quantum materials unlocks potential for alternative electronics October 15th, 2017

Injecting electrons jolts 2-D structure into new atomic pattern: Berkeley Lab study is first to show potential of energy-efficient next-gen electronic memory October 13th, 2017

The secret to improving liquid crystal's mechanical performance: Better lubricating properties of lamellar liquid crystals could stem from changing the mobility of their structural dislocations by adding nanoparticles October 13th, 2017

Announcements

Rice U. study: Vibrating nanoparticles interact: Placing nanodisks in groups can change their vibrational frequencies October 16th, 2017

Spin current detection in quantum materials unlocks potential for alternative electronics October 15th, 2017

Quantum manipulation power for quantum information processing gets a boost: Improving the efficiency of quantum heat engines involves reducing the number of photons in a cavity, ultimately impacting quantum manipulation power October 14th, 2017

The secret to improving liquid crystal's mechanical performance: Better lubricating properties of lamellar liquid crystals could stem from changing the mobility of their structural dislocations by adding nanoparticles October 13th, 2017

Events/Classes

Nanometrics Announces Preliminary Results for the Third Quarter of 2017: Quarterly Results Impacted by Delays in Revenue Recognition on Multiple Systems into Japan October 12th, 2017

More 22 of 59,885 Print all In new window Leti to Present Update of CoolCube/3DVLSI Technologies Development at 2017 IEEE S3S: Future Developments and Tape-Out Vehicles to Be Presented during Oct. 17 Workshop October 12th, 2017

Arrowhead Pharmaceuticals to Present Preclinical Data on ARO-AAT at The Liver Meeting(R) October 10th, 2017

Arrowhead to Present at Chardan Gene Therapy Conference October 3rd, 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