(Press-News.org) Contact information: Lynn Yarris
lcyarris@lbl.gov
510-486-5375
DOE/Lawrence Berkeley National Laboratory
Remembrances of things past
Berkeley Lab researchers discover nanoscale shape-memory oxide
Listen up nickel-titanium and all you other shape-memory alloys, there's a new kid on the block that just claimed the championship for elasticity and is primed to take over the shape memory apps market at the nanoscale. A research team at Berkeley Lab has discovered a way to introduce a recoverable strain into bismuth ferrite of up to 14-percent on the nanoscale, larger than any shape-memory effect observed in a metal. This discovery opens the door to applications in a wide range of fields, including medical, energy and electronics.
"Our bismuth ferrite not only displayed the champion shape-memory value, it was also far more stable when reduced to nanometer size than shape-memory alloys," says Jinxing Zhang, a post-doc for this study under Ramamoorthy Ramesh of Berkeley Lab's Materials Sciences Division and now a faculty member at Beijing Normal University. "Also because our bismuth ferrite can be activated with only an electrical field rather the thermal fields needed to activate shape-memory alloys, the response time is much faster."
The shape-memory effect is the metallic equivalent of elasticity, in which a solid material "remembers" and recovers its original shape after being deformed by an applied stress. In the past, this has always involved heating. Shape-memory alloys have had a big impact in the medical field with the most prominent being nickel-titanium or "nitinol," which is used in stents for angioplasty, and in mechanical joints. The shape-memory effect is also expected to have a major impact in non-medical applications, such as actuators in smart materials and in Microelectro-Mechanical Systems (MEMS). However, as the size of current shape-memory alloys shrink towards the nano-scale, numerous problems and instabilities arise, including fatigue, micro-cracking and oxidation.
"By achieving the shape-memory effect in an oxide material rather than a metal alloy, we eliminate the surface issues and enable integration with microelectronics," says Zhang. "Our bismuth ferrite also displays an ultra-high work function density during actuation that is almost two orders of magnitude higher than what a metal alloy can generate."
Bismuth ferrite is multiferroic compound comprised of bismuth, iron and oxygen that has been studied extensively in recent years by Ramesh and his research group. As a multiferroic, bismuth ferrite displays both ferroelectric and ferromagnetic properties, meaning it will respond to the application of external electric or magnetic fields. In this latest study, in addition to the conventional thermal activation, an elastic-like phase transition was introduced into bismuth ferrite using only an electric field.
"The application of the electric field allowed us to achieve a phase transformation that was reversible without the assistance of external recovery stress," Ramesh says. "Although aspects such as hysteresis, micro-cracking and so on have to be taken into consideration for real devices, the large shape-memory effect we demonstrated in bismuth ferrite shows it to be an extraordinary material with potential use in future nanoelectromechanical devices and other state-of-art nanosystems."
INFORMATION:
The bismuth ferrite shape-memory effect was characterized at the National Center for Electron Microscopy (NCEM), a U.S. Department of Energy national user facility housed at Berkeley Lab.
Results of this research were published in the journal Nature Communications. The paper was titled "A nanoscale shape-memory oxide." In addition to Zhang and Ramesh, other co-authors were
Xiaoxing Ke, Gaoyang Gou, Jan Seidel, Bin Xiang, Pu Yu, Wen-I Liang, Andrew Minor, Ying-hao Chu, Gustaaf Van Tendeloo and Xiaobing Ren.
Lawrence Berkeley National Laboratory addresses the world's most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab's scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy's Office of Science. For more, visit http://www.lbl.gov.
Remembrances of things past
Berkeley Lab researchers discover nanoscale shape-memory oxide
2013-12-03
ELSE PRESS RELEASES FROM THIS DATE:
1950s pandemic influenza virus remains a health threat, particularly to those under 50
2013-12-03
1950s pandemic influenza virus remains a health threat, particularly to those under 50
St. Jude Children's Research Hospital scientists report that avian H2N2 influenza A viruses related to 1957-1958 pandemic infect human cells and spread among ...
Higher case load lowers cost of repairing bones that protect eye
2013-12-03
Higher case load lowers cost of repairing bones that protect eye
Patients fare equally well at half the cost, study shows
Adding to evidence that "high-volume" specialty care in busy teaching hospitals leads to efficiencies unavailable in community hospitals, ...
UI biology professor finds 'Goldilocks' effect in snail populations
2013-12-03
UI biology professor finds 'Goldilocks' effect in snail populations
Finding may 1 day help control invasive species
A University of Iowa researcher has discovered that a "Goldilocks" effect applies to the reproductive output of a tiny New Zealand snail—considered ...
Alzheimer's risk gene may begin to affect brains as early as childhood, CAMH research shows
2013-12-03
Alzheimer's risk gene may begin to affect brains as early as childhood, CAMH research shows
Dec. 3, 2013 (Toronto) - People who carry a high-risk gene for Alzheimer's disease show changes in their brains beginning in childhood, decades before the illness ...
Hubble traces subtle signals of water on hazy worlds
2013-12-03
Hubble traces subtle signals of water on hazy worlds
U of T study finds that fear of being single leads people to settle for less in relationships
2013-12-03
U of T study finds that fear of being single leads people to settle for less in relationships
TORONTO, ON – Fear of being single is a meaningful predictor of settling for less in relationships among both men and women, a new University of Toronto (U of T) study has ...
Embargoed news from Annals of Internal Medicine -- 'Overweight and healthy' is a myth
2013-12-03
Embargoed news from Annals of Internal Medicine -- 'Overweight and healthy' is a myth
Annals of Internal Medicine tip sheet for 3 Dec. 2013
1. Evidence suggests that "healthy and overweight" is a myth
A systematic review and meta-analysis of observational ...
ACP recommends tighter transfusion strategy to treat anemia in patients with heart disease
2013-12-03
ACP recommends tighter transfusion strategy to treat anemia in patients with heart disease
New ACP guideline presents evidence-based recommendations for treating anemia in patients with heart disease
PHILADELPHIA, December 3, 2013 -- Red blood cell (RBC) transfusions ...
Scientists build a low-cost, open-source 3-D metal printer
2013-12-03
Scientists build a low-cost, open-source 3-D metal printer
Key ingredients are steel, a MIG welder, and a microcontroller
OK, so maybe you aren't interested in making your own toys, cellphone cases, or glow-in-the-dark Christmas decorations. How about ...
Specific heart contractions could predict atrial fibrillation
2013-12-03
Specific heart contractions could predict atrial fibrillation
UCSF-led team identifies potential new risk factor for cardiovascular patients
A commonly used heart monitor may be a simple tool for predicting the risk of atrial fibrillation, the most ...
LAST 30 PRESS RELEASES:
Women are 40% more likely to experience depression during the perimenopause
World’s highest observatory explores the universe
$27 million to map 50 million human cells and uncover genetic fingerprints of disease
Validated rules help prevent overuse of CT scans for diagnosing traumatic head and abdominal injuries in kids
Closing the U.S./Mexico border during COVID-19 increased HIV transmission
Researchers at Houston Methodist find difference in pancreatic cancer cells, offering new hope for immunotherapy effectiveness
Withdrawal of stop-smoking pill could lead to thousands of avoidable deaths
CT-ing is believing: Zeiss Xradia 630 Versa micro-CT scanner supports materials, life sciences research
Breakthrough in complex pain management
Astronomers share climate-friendly meeting solutions
Missing link in species conservation: Pharmacists, chemists could turn tide on plant, animal extinction
Illinois researchers develop an AI model to reduce uncertainty in evapotranspiration prediction
Is it time to retire the best-before date?
An electrifying discovery may help doctors deliver more effective gene therapies
Lurie Children’s Hospital first-in-pediatrics to use technology that lights up lung cancer during surgery
$3.6 million to advance nuclear energy awarded to U-M
Two UT Arlington faculty honored for outstanding research
UT Arlington student links worm behavior to brain disease
Uncovering the secret of long-lived stem cells
The question for online educational platforms: offer courses following a schedule or release them on demand?
Study: racial bias is no 'false alarm' in policing
Ecological Society of America announces 2024 Fellows
Mass General Brigham researchers identify potential drivers of chronic allergic inflammation
Scientists solve chemical mystery at the interface of biology and technology
Shaping the Future of Neuroendocrine Tumor Management
Scientists show ancient village adapted to drought, rising seas
Cover paper: Senescent characteristics of human corneal endothelial cells upon UV-A exposure
Activity in a room stirs up nanoparticles left over from consumer sprays
NASA’s Webb maps weather on planet 280 light-years away
Webb captures top of iconic horsehead nebula in unprecedented detail
[Press-News.org] Remembrances of things pastBerkeley Lab researchers discover nanoscale shape-memory oxide