Graphene nanoribbons formed into a 3-D aerogel and enhanced with boron and nitrogen are excellent catalysts for fuel cells, even in comparison to platinum, according to Rice Univ. researchers. A team led by materials scientist Pulickel Ajayan and chemist James Tour made metal-free aerogels from graphene nanoribbons and various levels of boron and nitrogen to test their electrochemical properties.
In science, it’s commonly known that materials can change in a number of ways when subjected to different temperatures, pressures or other environmental forces. A material might melt or snap in half. And for engineers, knowing when and why that might happen is crucial information. Now, a Florida State Univ. researcher has laid out an overarching theory that explains why certain materials act the way they do.
Wake up in the morning and stretch; your midsection narrows. Pull on a piece of plastic at separate ends; it becomes thinner. So does a rubber band. One might assume that when a force is applied along an axis, materials will always stretch and become thinner. Wrong.
A superconductor that works at room temperature was long thought impossible, but scientists at the Univ. of Southern California may have discovered a family of materials that could make it reality. The team found that aluminum "superatoms" appear to form Cooper pairs of electrons at temperatures around 100 K. Though 100 K is still pretty chilly, this is an increase compared to bulk aluminum metal.
To power a car so it can travel hundreds of miles at a time, lithium-ion batteries of the future are going to have to hold more energy without growing too big in size. That's one of the dilemmas confronting efforts to power cars through rechargeable battery technologies. In order to hold enough energy to enable a car trip of 300 to 500 miles before recharging, current lithium-ion batteries become too big or too expensive.
Superconductor materials are prized for their ability to carry an electric current without resistance, but this valuable trait can be crippled or lost when electrons swirl into tiny tornado-like formations called vortices. These disruptive mini-twisters often form in the presence of magnetic fields, such as those produced by electric motors.
Scientists have known how to draw thin fibers from bulk materials for decades. But a new approach to that old method, developed by researchers at Massachusetts Institute of Technology, could lead to a whole new way of making high-quality fiber-based electronic devices. The idea grew out of a long-term research effort to develop multifunctional fibers that incorporate different materials into a single long functional strand.
Graphene is often touted as a replacement for silicon in electronic devices due to its extremely high conductivity and unbeatable thinness. But graphene isn’t the only 2-D material that could play such a role. Univ. of Pennsylvania researchers have made an advance in manufacturing one such material, molybdenum disulphide.
Researchers succeeded in creating an electrocatalyst that is needed for storing electric energy made of carbon and iron. A challenge that comes with the increased use of renewable energy is how to store electric energy. Platinum has traditionally been used as the electrocatalyst in electrolyzers that store electric energy as chemical compounds.
Researchers at the Univ. of California, Riverside have developed a novel paper-like material for lithium-ion batteries. It has the potential to boost by several times the specific energy, or amount of energy that can be delivered per unit weight of the battery. This paper-like material is composed of sponge-like silicon nanofibers more than 100 times thinner than human hair.
A team of researchers from the Univ. of Michigan and Western Michigan Univ. is exploring new materials that could yield higher computational speeds and lower power consumption, even in harsh environments. Most modern electronic circuitry relies on controlling electronic charge within a circuit, but this control can easily be disrupted in the presence of radiation, interrupting information processing.
Compact, sensitive and fast nanodetectors are considered to be somewhat of a "Holy Grail" sought by many researchers around the world. And now a team of scientists in Italy and France has been inspired by nanomaterials and has created a novel solid-state technology platform that opens the door to the use of terahertz photonics in a wide range of applications.
The future of electronics could lie in a material from its past, as researchers from The Ohio State Univ. work to turn germanium, the material of 1940s transistors, into a potential replacement for silicon. At the American Association for the Advancement of Science meeting, Asst. Prof. of Chemistry Joshua Goldberger reported progress in developing a form of germanium called germanane.
A research team led by North Carolina State Univ. has identified and synthesized a material that can be used to create efficient plasmonic devices that respond to light in the mid-infrared (IR) range. This is the first time anyone has demonstrated a material that performs efficiently in response to this light range, and it has applications in fields ranging from high-speed computers, to solar energy to biomedical devices.
Although most materials slightly expand when heated, there is a new class of rubber-like material that not only self-stretches upon cooling; it reverts back to its original shape when heated, all without physical manipulation. The material is like a shape-memory polymer because it can be switched between two different shapes.
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.
With a low price tag and mild flavor, tilapia has become a staple dinnertime fish for many Americans. Now it could have another use: helping to heal our wounds. In ACS Applied Materials & Interfaces, scientists have shown that a protein found in this fish can promote skin repair in rats without an immune reaction, suggesting possible future use for human patients.
Researchers from North Carolina State Univ. are using a technique they developed to observe minute distortions in the atomic structure of complex materials, shedding light on what causes these distortions and opening the door to studies on how such atomic-scale variations can influence a material's properties.
Scientists used supercomputers to find a new class of materials that possess an exotic state of matter known as the quantum spin Hall effect. The researchers published their results in Science in December 2014, where they propose a new type of transistor made from these materials. The team calculated the electronic structures of the materials using the Stampede and Lonestar supercomputers of the Texas Advanced Computing Center.
More than 80% of microbial infections in the human body are caused by a build–up of bacteria, according to the National Institutes of Health. Bacteria cells gain a foothold in the body by accumulating and forming into adhesive colonies called biofilms, which help them to thrive and survive but cause infections and associated life–threatening risks to their human hosts.
How do you make nickel look and behave like copper? A team of scientists at Yale Univ. has done just that by developing a novel technique to artificially alter a material’s atomic properties by substantially modifying the orbital properties of electrons. The electrons can also be tunably configured in orbital patterns with unique magnetic, superconductive and optical properties.
Treated buckyballs not only remove valuable but potentially toxic metal particles from water and other liquids, but also reserve them for future use, according to scientists at Rice Univ. The Rice lab of chemist Andrew Barron has discovered that carbon-60 fullerenes (buckyballs) that have gone through the chemical process known as hydroxylation aggregate into pearl-like strings as they bind to and separate metals from solutions.
Metamaterials offer tantalizing future prospects such as high-resolution optical microscopes and superfast optical computers. To realize the vast potential of metamaterials, however, scientists will need to hone their understanding of the fundamental physics behind them. This will require accurately predicting nonlinear optical properties.
Injectable nanoparticles that could protect an injured person from further damage due to oxidative stress have proven to be astoundingly effective in tests to study their mechanism. A team of scientists designed methods to validate their 2012 discovery that combined polyethylene glycol-hydrophilic carbon clusters could quickly stem the process of overoxidation that can cause damage in the minutes and hours after an injury.
Artists, print designers and interior decorators have long had access to a broad palette of paint and ink colors for their work. Now, researchers have created a broad color palette of electrochromic polymers, materials that can be used for sunglasses, window tinting and other applications that rely on electrical current to produce color changes.