Ferroelectrics refer to materials with spontaneous electric polarization that can be switched by external electric fields. They are very similar to magnets but with electric instead of magnetic polarization. Besides their widespread applications in piezoelectric nanopositioners and ferroelectric RAMs that make use of the net ferroelectric polarization, the spatial arrangements of polarization domains in nominal atomic layers of ferroelectrics are also considered for high-density information storage due to their well-defined spatial structures with characteristic lengths as small as a few nm. The stability of the domain structures is therefore key to the design of non-volatile memories. However, tracking the domain motion in real time is extremely challenging as it requires detecting sub-angstrom atomic fluctuation on a nanometer spatial scale at elevated temperature. Researchers using the U.S. Department of Energy’s Advanced Photon Source overcame this obstacle with their study of serpentine striped ferroelectric nanodomains in a ferroelectric/dielectric superlattice. Ferroelectric polarization ordering is a promising candidate for self-assembly growth next-generation information storage, so their results provide a quantitative approach for measuring the stability of these structures, providing essential information for both modeling and application of complex ferroelectric oxides in a variety of technologies.
Some materials are like people. Let them relax in the sun for a little while and they perform a lot better. A collaboration carrying out research at the U.S. Department of Energy’s Advanced Photon Source found that to be the case with a perovskite compound touted as an efficient material to collect sunlight and convert it into energy.
With help from the U.S. Department of Energy’s Advanced Photon Source, researchers revealed the mechanism for metal-like heat performance in polymers. The team’s results may spur the development of polymer insulators as lightweight, flexible, and corrosion-resistant alternatives to traditional metal heat conductors, for applications ranging from heat dissipating materials in laptops and cellphones, to cooling elements in cars and refrigerators.
A university-national laboratory team of researchers has found a promising solution to those problems in a perovskite compound that actually expands under illumination, smoothing out defects in its crystal lattice and allowing more efficient charge transport across the interface, with improved power conversion efficiency) to over 20%.
Investigations at the U.S. Department of Energy’s Advanced Photon Source have demonstrated that a diiminol-based covalent organic framework can act as a rapid humidity sensor with an easily visible color change, providing an important proof-of-concept for using tautomerization-induced changes in COFs to design rapid and reversible sensing systems.
Printing Ultrathin 2-D Polymer Electronics: The relatively simple techniques demonstrated by the researchers in this study may lead to the mass production of inexpensive, ultrathin polymer films down to monolayer thickness, with potential applications including photovoltaics, sensors, and wearable electronics.
Strong and Resilient Synthetic Tendons Produced from Hydrogels: Researchers who transformed a standard hydrogel into an artificial tendon with properties that meet and even surpass those of natural tendons used the the U.S. Department of Energy’s Advanced Photon Source to reveal the microscopic structures responsible for its outstanding features.
Now, a group of researchers has used the U.S. Department of Energy's Advanced Photon Source to examine how 2-D lead iodide perovskites form in real time. They found a method to enhance the quality of the 2-D cells, and now have a basis for rationally designing manufacturing techniques for high-quality commercial lead iodide perovskite solar cells.
Knowledge about colloidal gel formation and dissolution has implications for understanding the preparation and stability of many consumer goods such as milk and yogurt, and personal care products such as cosmetics. At the same time, more fundamentally, colloidal gels exhibit physical behavior that can help address challenging scientific problems such as the formation, stability, and dynamics of glasses. Studies by a research team utilizing high-brightness x-rays from the U.S. Department of Energy’s Advanced Photon Source provide important insight into a key question that has long puzzled scientists in the field, namely, why do nanoparticle gels take so long to form after a quench even though the constituent nanoparticles are rapidly diffusing through the suspension?
Findings based on research at the U.S. Department of Energy’s Advanced Photon Source are critical to our understanding of nucleation and growth dynamics, which underlie the desired properties and use of soft and hard materials in a variety of applications, including pressure sensitive adhesives, thermoplastics, microelectronics, and cardiovascular stents.
Slow Flow and Sudden Avalanches Relax Stress in Glasses: When familiar solids like metal, wood, or rubber are deformed, a consistent restoring force appears that pushes back against the deformation. Research at the U.S. Department of Energy’s Advanced Photon may guide new strategies for processing amorphous solids and could also provide new theoretical insights into the factors underlying their dynamic behavior.
The upcoming APS Upgrade makes the need for high-frame-rate detectors especially acute because the tremendous gains in coherent flux will, in principle, increase the best time resolution of XPCS by 4 orders of magnitude, allowing measurements of nanoscale fluctuations in aqueous environments such as those relevant to biochemical function.
Proteins of a Feather Come Together to Create Color: Biologists would like to understand how and why birds are brightly colored. Some materials scientists look to nature to find better ways to recreate such colors. A study conducted using the U.S. Department of Energy’s Advanced Photon Source points to possible answers to both those questions and represents the first directly self-assembled single gyroid crystals known to science, potentially opening new photonic technologies.
Measuring Cartilage Dynamics at Nanoscale: Researchers used high brightness x-rays at the U.S. Department of Energy’s Advanced Photon Source to advance our understanding of cartilage dynamics and demonstrate a valuable new research tool.
Relaxing with Soft Materials: A team of investigators used the U.S. Department of Energy’s Advanced Photon Source for their studies of the detailed microscopic dynamics of relaxation in a model soft gel, establishing a previously elusive connection between the rearrangement events occurring on the microscopic scale and the observable stress relaxation behavior on the macroscale.