Sandia National Laboratories researchers have made the first measurements of thermoelectric behavior by a nanoporous metal-organic framework (MOF), a development that could lead to an entirely new class of materials for such applications as cooling computer chips and cameras and energy harvesting. This work builds on previous research in which the Sandia team realized electrical conductivity in MOFs by infiltrating the pores with TCNQ.
Non-metallic mesoporous structures have already demonstrated potential for applications in gas...
Researchers have demonstrated a new metal matrix composite that is so light that it can float on...
New work from the Carnegie Institution’s Russell Hemley and Ivan Naumov hones in on the physics underlying the recently discovered fact that some metals stop being metallic under pressure. Metals are compounds that are capable of conducting the flow of electrons that make up an electric current.
Researchers from North Carolina State Univ. have discovered that electron spin brings a previously unknown degree of order to the high entropy alloy nickel iron chromium cobalt (NiFeCrCo), and may play a role in giving the alloy its desirable properties.
Proximity effects in hybrid heterostructures, which contain distinct layers of different materials, allow one material species to reveal and/or control properties of a dissimilar species. Specifically, for a magnetic thin film deposited onto a transition metal oxide film, the magnetic properties change dramatically as the oxide undergoes a structural phase transition.
Sudden cardiac death accounts for approximately 10 percent of natural deaths, most of which are due to ventricular fibrillation. Each year it causes 300,000 deaths in the United States and 20,000 in Spain. Researchers have demonstrated for the first time that the transition to calcium alternans, an arrhythmia associated with increased risk of sudden death, has common features with the magnetic ordering of metals.
A research team has investigated the electronic properties of the family of unconventional superconductors based on fullerenes, which have the highest known superconducting critical temperature among molecular superconductors, and was able to demonstrate the guiding influence of the molecular electronic structure in controlling superconductivity and achieving maximum Tc.
Just as a delicate balance of ingredients determines the tastiness of a cookie or cake, the specific ratio of metals in an alloy determines desirable qualities of the new metal, such as improved strength or lightness. A new class of alloys, called high entropy alloys, is unique in that these alloys contain five or more elements mixed evenly in near equal concentrations and have shown exceptional engineering properties.
The fantasy epic Game of Thrones is back April 12, 2015, and it is sure to be chock full of intrigue, indiscretions and, of course, swords. The most sought-after blades in Westeros are made from Valyrian steel, forged using ancient magic. But could you make your own Valyrian steel sword using real-life chemistry?
In a new paper, a team of Yale Univ. researchers assesses the “criticality” of all 62 metals on the Periodic Table of Elements, providing key insights into which materials might become more difficult to find in the coming decades, which ones will exact the highest environmental costs and which ones simply cannot be replaced as components of vital technologies.
One third of the world’s food-producing land has been lost in the past 40 years as a result of soil degradation, putting global food security at risk. Researchers have discovered how aluminum, a toxic result of soil acidification, acts to reduce plant growth.
As you heat up a piece of iron, the arrangement of the iron atoms changes several times before melting. This unusual behavior is one reason why steel, in which iron plays a starring role, is so sturdy and ubiquitous in everything from teapots to skyscrapers. But the details of just how and why iron takes on so many different forms have remained a mystery.
Researchers have demonstrated a technique for mapping deformation in metals that can recover destroyed serial numbers on metal objects such as firearms, a common challenge in forensics. The technique might also meet other forensic needs such as reconstructing vehicle identification numbers or imprints on ammunition casings.
When a metal tube lines an oil well thousands of feet below the surface of the ocean, that metal had better be solid and reliable. Unfortunately, the environment in such deep wells is often rich in hydrogen, a gas that can penetrate high-tech alloys and make them brittle, making fractures and leaks more likely. Now researchers have figured which characteristics of a metal structure foster this embrittlement in the presence of hydrogen.
Earth’s magnetic field is crucial for our existence, as it shields the life on our planet’s surface from deadly cosmic rays. It is generated by turbulent motions of liquid iron in Earth’s core. Iron is a metal, which means it can easily conduct a flow of electrons that makes up an electric current. New findings show a missing piece of the traditional theory explaining why metals become less conductive when they are heated.
Rust never sleeps. Whether a reference to the 1979 Neil Young album or a product designed to protect metal surfaces, the phrase invokes the idea that corrosion from oxidation is an inevitable, persistent process. But a new Binghamton Univ. study reveals that certain features of metal surfaces can stop the process of oxidation in its tracks.
Researchers have developed a new “high-entropy” metal alloy that has a higher strength-to-weight ratio than any other existing metal material. High-entropy alloys are materials that consist of five or more metals in approximately equal amounts.
Nanoporous metals have a wide range of applications because of their superior qualities. They posses a high surface area for better electron transfer, which can lead to the improved performance of an electrode in an electric double capacitor or battery. Nanoporous metals offer an increased number of available sites for the adsorption of analytes, a highly desirable feature for sensors.
Yale Univ. engineer Jan Schroers will lead a three-year, $1.2 million project intended to dramatically accelerate the pace of discovering and characterizing bulk metallic glasses (BMGs), a versatile type of pliable glass that’s stronger than steel. The grant will enable Schroers’ team to screen more than 3,000 potential BMG alloys in a week, a vast improvement over traditional methods.
Research at Oak Ridge National Laboratory has cracked one mystery of glass to shed light on the mechanism that triggers its deformation before shattering. The study improves understanding of glassy deformation and may accelerate broader application of metallic glass, a moldable, wear-resistant, magnetically exploitable material that is thrice as strong as the mightiest steel and ten times as springy.
Univ. of Texas at Arlington engineering professors have received an Air Force grant to examine the material surface at the micro- and nano-scale level that will provide clues for predicting fatigue in aircraft parts. The new approach will rely on a scanning whitelight interferometric surface profiler integrated with a compact mechanical tester and an electron backscatter diffraction module to deliver in-situ 3-D surface profiling.
The phase-out of traditional incandescent bulbs in the U.S. and elsewhere, as well as a growing interest in energy efficiency, has given LED lighting a sales boost. That trend could be short-lived as key materials known as rare earth elements become more expensive. Scientists at Rutgers Univ., however, have now designed new materials for making household LED bulbs without using these ingredients.
Iron catalysts remove oxygen inexpensively, but are susceptible to rust or oxidation in biofuel production. Precious metals that resist corrosion are even less efficient at removing oxygen. But adding just a touch of palladium to the iron produces a catalyst that quickly removes oxygen atoms, easily releases the desired products, and doesn't rust, according to scientists at Pacific Northwest National Laboratory and Washington State Univ.
Swedish and Chinese researchers have recently shown how a unique nano-alloy composed of palladium nano-islands embedded in tungsten nanoparticles creates a new type of catalysts for highly efficient oxygen reduction, the most important reaction in hydrogen fuel cells. Their results are published in the scientific journal Nature Communications.
The key to creating a material that would be ideal for converting solar energy to heat is tuning the material’s spectrum of absorption just right: It should absorb virtually all wavelengths of light that reach Earth’s surface from the sun—but not much of the rest of the spectrum, since that would increase the energy that is reradiated by the material, and thus lost to the conversion process.
Researchers are developing a robotic fabric that moves and contracts and is embedded with sensors, an approach that could lead to "active clothing" or a new class of "soft" robots. The robotic fabric, developed at Purdue Univ., is a cotton material containing sensors made of a flexible polymer and threadlike strands of a shape-memory alloy that return to a coiled shape when heated, causing the fabric to move.
Donald Sadoway and his colleagues at the Massachusetts Institute of Technology have already started a company to produce electrical-grid-scale liquid batteries, whose layers of molten material automatically separate due to their differing densities. But a newly developed formula substitutes different metals for the molten layers. The new formula allows the battery to work at a much lower temperature.
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