Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Bottom-up approach provides first characterization of pyroelectric nanomaterials

Using a high-power, pulsed laser to deposit materials from a plasma plume (shown here), researchers synthesized materials to study their unique pyroelectric properties at the nanoscale.
Using a high-power, pulsed laser to deposit materials from a plasma plume (shown here), researchers synthesized materials to study their unique pyroelectric properties at the nanoscale.

Abstract:
By taking a "bottom-up" approach, researchers at the University of Illinois at Urbana-Champaign have observed for the first time that "size does matter" in regards "pyroelectricity"—the current/voltage developed in response to temperature fluctuations that enables technologies such as infrared sensors, night-vision, and energy conversion units, to name a few.

Bottom-up approach provides first characterization of pyroelectric nanomaterials

Urbana, IL | Posted on January 8th, 2013

"Controlling and manipulating heat for applications such as waste heat energy harvesting, integrated cooling technologies, electron emission, and related functions is an exciting field of study today," explained Lane Martin, an assistant professor of materials science and engineering at Illinois. "Traditionally, these systems have relied on bulk materials, but future nanoscale devices will increasingly require ferroelectric thin films.

"Measuring the pyroelectric response of thin films is difficult and has restricted the understanding of the physics of pyroelectricity, prompting some to label it as 'one of the least-known properties of solid materials'," Martin added. "This work provides the most complete and detailed modeling and experimental study of this widely unknown region of materials and has direct implications for next generation devices."

Researchers found that reducing the dimensions of ferroelectrics increases their susceptibility to size- and strain-induced effects. The group's paper, "Effect of 90-degree domain walls and thermal expansion mismatch on the pyroelectric properties of epitaxial PbZr0.2Ti0.8O3 thin films," appears in the journal Physical Review Letters.

"What we did in this work was to develop a new approach to utilize and understand a class of materials important for all of these applications," Martin said. "By moving to a 'bottom-up' approach that produces nanoscale versions of these materials as thin films, we have observed, for the first time, that certain features, namely domain walls, can be incredibly important and even dominate the temperature-dependent response and performance of these materials."

According to J. Karthik, the first author on the group's paper, thin-film epitaxy has been developed to provide a set of parameters (e.g., film composition, epitaxial strain, electrical boundary conditions, and thickness) that allow for precise control of ferroelectrics and has been instrumental in understanding the physics of dielectric and piezoelectric effects.

"We investigated the contribution of 90º domain walls and thermal expansion mismatch to pyroelectricity in ferroelectric PbZr0.2Ti0.8O3 thin films, a widely used material whose bulk ferroelectric and piezoelectric properties are well understood," Karthik explained. As part of this work, Martin's Prometheus research group developed and applied the first phenomenological models to include extrinsic and secondary contributions to pyroelectricity in polydomain films and predict significant extrinsic contributions (arising from the temperature-dependent motion of domain walls) and large secondary contributions (arising from thermal expansion mismatch between the film and the substrate).

"We have also developed and applied a new phase-sensitive pyroelectric current measurement process to measure thin films for the first time and reveal a dramatic increase in the pyroelectric coefficient with increasing fraction of in-plane oriented domains and thermal expansion mismatch consistent with these models," Karthik said.

"By establishing an understanding of the science of these effects, with models to predict their performance, and demonstrated techniques to fabricate and utilize these properties in nanoscale versions of these materials, their properties can be effectively integrated into existing electronics," Martin said.

This research was supported by the Office of Naval Research, the Army Research Office, and the Air Force Office of Scientific Research.

####

For more information, please click here

Contacts:
Lane Martin, Ph.D.

217-244-9162

Copyright © University of Illinois College of Engineering

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

News and information

The next step in DNA computing: GPS mapping? May 6th, 2015

Improving Clinical Care and Patient Quality of Life in Advanced Liver Disease, d-LIVER Workshop, Milan, 27 May 2015 May 6th, 2015

Grafoid Acquires MuAnalysis Inc; Expands Its Advanced Materials Testing Capabilities May 6th, 2015

Winner Announced for NNI’s First ‘EnvisioNano’ Nanotechnology Image Contest May 6th, 2015

Thin films

Improving organic transistors that drive flexible and conformable electronics: UMass Amherst scientists advance understanding of strain effects on performance May 5th, 2015

'Microcombing' creates stronger, more conductive carbon nanotube films May 5th, 2015

ORNL researchers probe chemistry, topography and mechanics with one instrument May 2nd, 2015

Unique microscopic images provide new insights into ionic liquids April 28th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Thermometer-like device could help diagnose heart attacks May 6th, 2015

Winner Announced for NNI’s First ‘EnvisioNano’ Nanotechnology Image Contest May 6th, 2015

New chip architecture may provide foundation for quantum computer: Researchers at the Georgia Tech Research Institute have developed a microfabricated ion trap architecture that holds promise for increasing the density of qubits in future quantum computers May 5th, 2015

'Microcombing' creates stronger, more conductive carbon nanotube films May 5th, 2015

Sensors

New chip architecture may provide foundation for quantum computer: Researchers at the Georgia Tech Research Institute have developed a microfabricated ion trap architecture that holds promise for increasing the density of qubits in future quantum computers May 5th, 2015

Iranian Scientists Present Model to Study Mechanical Vibrations of Structures Containing Nanocomposites May 5th, 2015

Making robots more human April 29th, 2015

Simultaneous Measurement of Drugs Made Possible by Nanosensors April 29th, 2015

Discoveries

Thermometer-like device could help diagnose heart attacks May 6th, 2015

The next step in DNA computing: GPS mapping? May 6th, 2015

Field-effect transistors on hybrid perovskites fabricated for first time May 6th, 2015

Improving organic transistors that drive flexible and conformable electronics: UMass Amherst scientists advance understanding of strain effects on performance May 5th, 2015

Announcements

The next step in DNA computing: GPS mapping? May 6th, 2015

Improving Clinical Care and Patient Quality of Life in Advanced Liver Disease, d-LIVER Workshop, Milan, 27 May 2015 May 6th, 2015

Grafoid Acquires MuAnalysis Inc; Expands Its Advanced Materials Testing Capabilities May 6th, 2015

Winner Announced for NNI’s First ‘EnvisioNano’ Nanotechnology Image Contest May 6th, 2015

Military

From brittle to plastic in 1 breath: Rice University theorists show environments can alter 2-D materials' basic properties May 4th, 2015

No Hogwarts invitation required: Invisibility cloaks move into the real-life classroom: A new solid-state device can demonstrate the physical principles of invisibility cloaks without special equipment or magic spells April 30th, 2015

Chemists strike nano-gold: 4 new atomic structures for gold nanoparticle clusters: Research builds upon work by Nobel Prize-winning team from Stanford University April 28th, 2015

Two-dimensional semiconductor comes clean April 27th, 2015

Energy

Field-effect transistors on hybrid perovskites fabricated for first time May 6th, 2015

Testing Facility for Graphene Enhanced Composite Pipes May 5th, 2015

Engineering a better solar cell: UW research pinpoints defects in popular perovskites May 1st, 2015

Artificial photosynthesis could help make fuels, plastics and medicine April 29th, 2015

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