In a rare case of having their cake and eating it too, scientists from NIST and other institutions have developed a toolset that allows them to explore the complex interior of tiny, multi-layered batteries they devised. It provides insight into the batteries’ performance without destroying them, which results in both a useful probe for scientists and a potential power source for micromachines.
A novel x...
If it's true that good things come in small packages, then NIST can now make anyone working with nanoparticles very happy. The institute recently issued Reference Material (RM) 8027, the smallest known reference material ever created for validating measurements of man-made, ultrafine particles between 1 and 100 nm in size.
using an aberration-corrected scanning transmission electron microscope, researchers have recently understood how defects in 2-D crystals such as tungsten disulphide can move, or dislocate, to other locations in the material. Understanding how atoms "glide" and "climb" on the surface of 2-D crystals may pave the way for researchers to develop materials with unusual or unique characteristics.
Researchers have discovered a way to create a highly sensitive chemical sensor based on the crystalline flaws in graphene sheets. The imperfections have unique electronic properties that the researchers were able to exploit to increase sensitivity to absorbed gas molecules by 300 times.
Researchers in Switzerland have succeeded in observing the “forbidden” infrared spectrum of a charged molecule for the first time. These extremely weak spectra offer perspectives for extremely precise measurements of molecular properties and may also contribute to the development of molecular clocks and quantum technology.
While freestanding graphene offers promise as a replacement for silicon and other materials in microprocessors and next-generation energy devices, much remains unknown about its mechanical and thermal properties. An international team of physicists, led by a research group at the Univ. of Arkansas, has recently discovered that heating can be used to control the curvature of ripples in freestanding graphene.
Researchers in Russia have developed a new method for the industrial synthesis of an ultra-hard material that exceeds diamond in hardness. An article recently published in Carbon describes in detail a method that allows for the synthesis of ultrahard fullerite, a polymer composed of fullerenes, or spherical molecules made of carbon atoms.
A comprehensive look at how tiny particles in a lithium-ion battery electrode behave shows that rapid-charging the battery and using it to do high-power, rapidly draining work may not be as damaging as researchers had thought—and that the benefits of slow draining and charging may have been overestimated.
A new study published in The Journal of Geology provides support for the theory that a cosmic impact event over North America some 13,000 years ago caused a major period of climate change known as the Younger Dryas stadial, or “Big Freeze.” The key to the mystery of the Big Freeze lies in nanodiamonds scattered across Europe, North America, and portions of South America.
Plastics are made of polymers, which are a challenge for scientists to study. Their chain-like strands of thousands of atoms are tangled up in a spaghetti-like jumble, their motion can be measured at many time scales and they are essentially invisible to some common x-ray study techniques. A better understanding of polymers at the molecular scale could lead to improved manufacturing techniques and the creation of new materials.
On the macroscale, adding fluorine atoms to carbon-based materials makes for water-repellant, non-stick surfaces, such as Teflon. However, on the nanoscale, adding fluorine to graphene vastly increased the friction experienced when sliding against the material. Through a combination of physical experiments and atomistic simulations, a Univ. of Pennsylvania research team has discovered the mechanism behind this surprising finding.
A new concept in metallic alloy design has yielded a multiple-element material that not only tests out as one of the toughest on record, but, unlike most materials, the toughness as well as the strength and ductility of this alloy actually improves at cryogenic temperatures. This multi-element alloy was synthesized and tested through a collaboration of researchers.
Researchers at Oak Ridge National Laboratory got a surprise when they built a highly ordered lattice by layering thin films containing lanthanum, strontium, oxygen and iron. Although each layer had an intrinsically nonpolar distribution of electrical charges, the lattice had an asymmetric distribution of charges.
The most familiar photovoltaic (PV) designs use rigid layers of silicon crystal, but recently inexpensive organic semiconductor materials have also been used successfully. At this time, organic PV devices are hindered by low efficiency, in part because quantifying their electrical properties is a challenge. Researchers have now developed a method that allows the prediction of the current density-voltage curve of a photovoltaic device.
A team of researchers in the U.S. and China have developed a new sensor that can detect and count nanoparticles, at sizes as small as 10 nm, one at a time. The researchers say the sensor, which is a Raman microlaser sensor in a silicon dioxide chip that does not need rare-earth ions to achieve high resolution, could potentially detect much smaller particles, viruses and small molecules.
Researchers have discussed the merits of surface-stress influence on mechanical properties for decades. Now, a new research platform, called nanomechanical Raman spectroscopy and developed at Purdue Univ., uses a laser to measure the "nanomechanical" properties of tiny structures undergoing stress and heating.
Bridges become an infrastructure problem as they get older, as de-icing salt and carbon dioxide gradually destroy the reinforced concrete. A new robot called C2D2 (Climbing Corrosion Detecting Device) is now in use in Switzerland and can check the condition of these structures, even in places that people cannot reach.
A team of scientists from Germany, Canada, and the United States has now developed a promising new measurement method that works without destroying anything yet offers nanoscale resolution. The method, an enhancement of resonant x-ray reflectometry identifies the chemical elements involved and is able to determine both the magnetic order and the electron distribution.
A mechanical engineering student at EPFL in Switzerland wanted to understand the reason behind the formation of a “foam volcano” after tapping the neck of a bottle of beer. He studied the phenomenon with a high-speed camera and compared it to the outcome of applying the same action to sparkling water. His work offers insights into the behavior of cavitation nuclei.
Electronic devices with unprecedented efficiency and data storage may someday run on ferroelectrics—remarkable materials that use built-in electric polarizations to read and write digital information, outperforming the magnets inside most popular data-driven technology. But ferroelectrics must first overcome a few key stumbling blocks, including a curious habit of "forgetting" stored data.
Since 2006, when NASA’s Stardust spacecraft delivered its aerogel and aluminum foil dust collectors back to Earth, a team of scientists has combed through them. They now report finding seven dust motes that probably came from outside our solar system, perhaps created in a supernova explosion and altered by eons of exposure to the extremes of space. They would be the first confirmed samples of contemporary interstellar dust.
The physical properties of the ultra-white scales on certain species of beetle could be used to make whiter paper, plastics and paints, while using far less material than is used in current manufacturing methods. Current technology is not able to produce a coating as white as these beetles can in such a thin layer, and spectroscopic analyses are revealing how this colorization is achieved through a dense complex network of chitin.
The “Bearded Man, 170-180 A.D.” is a Roman-Egyptian portrait that adorned the sarcophagus sheltering his mummified remains. The details of who he was have been lost to time, but a microscopic sliver of painted wood could hold the keys to unraveling the first part of this centuries-old mystery. Figuring out what kind of pigment was used, and the exact materials used to create it, could help scientists unlock his identity.
Graphene may be tough, but those who handle it had better be tender. The environment surrounding the atom-thick carbon material can influence its electronic performance, according to researchers at Rice and Osaka universities who have come up with a simple way to spot contaminants.
Zeolites used extensively in industry are promising catalysts that turn biomass into transportation fuels, but the activity and stability of this class of materials is challenging to understand and predict. Employing a combination of methods devised at Pacific Northwest National Laboratory and the Swiss Light Source, scientists were able to determine the distribution of aluminum ions in structural variants of zeolites.
Researchers at the National Physical Laboratory in the U.K. have discovered that the conductivity at the edges of graphene devices is different to the central material. The group used local scanning electrical techniques to examine the local nanoscale electronic properties of epitaxial graphene, in particular the differences between the edges and central parts of graphene Hall bar devices.
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