Researchers from the Max Planck Institute for Intelligent Systems in Stuttgart have developed a new method for the active degradation of organic pollutants in solution by using swimming microengines. These tiny “engines” are made from platinum and iron and are highly efficient in removing organic pollutants from water using hydrogen peroxide.
In 2007 and 2008, two research papers reported in the journal Nature that a suite of zircons from the Jack Hills included diamonds, requiring a radical revision of early Earth history. The papers posited that the diamonds formed, somehow, before the oldest zircons, or more than 4.3 billion years ago. A research team now claims the oldest “diamonds” on the Earth are simply fragments of polishing compound.
A new method for extracting titanium significantly reduces the energy required to separate it from its tightly bound companion, oxygen. Scientists have discovered that they could eliminate the energy-intensive steps of the Kroll process, a finding that could lower cost and accessibility of future titanium products.
Quantum dots have potential for applications that make use of their ability to absorb or emit light and/or electric charges. Examples include more vividly colored light-emitting diodes (LEDs), photovoltaic solar cells, nanoscale transistors and biosensors. But because these applications have differing, sometimes opposite, requirements, finding ways to control the dots’ optical and electronic properties is crucial to their success.
Modern epoxies are frequently made stronger, lighter and more resilient with the addition of multiwalled carbon nanotubes (MWCNTs), a special form of carbon that under a microscope looks like rolls of chicken wire. Few analytical methods have been employed, however, to determine the effect this material has on environmental or health safety. NIST has developed a suite of tests for evaluating the performance of these nanocomposite materials.
Supramolecular chemistry is just beginning to come into its own with the emergence of nanotechnology. Metal organic frameworks (MOFs) are commanding much of the attention because of their appetite for greenhouse gases, but a new player has joined the field—supramolecular organic frameworks (SOFs). Researchers have unveiled the first 2-D SOFs that self-assemble in solution.
The Ulsan National Institute of Science and Technology in Korea has developed a new method for the mass production of boron/nitrogen co-doped graphene nanoplatelets, which could lead to the fabrication of a graphene-based field-effect transistor with semiconducting nature. This opens up opportunities for practical use in electronic devices.
Lithium-ion batteries could have significantly higher energy density if their graphite anodes were to be replaced by lithium metal anodes. Hampering this change, however, has been the persistent growth of dendrites that eventually short-circuit the battery. Researchers have recently discovered that the bulk of dendrite material lies below the surface of the lithium electrode, underneath the electrode/electrolyte interface.
Graphene, a two-dimensional array of carbon atoms, has shown great promise for a variety of applications, but for many suggested uses the material requires treatments that can be expensive and difficult to apply predictably. Now, a team of researchers has found a simple, inexpensive treatment that may help to unleash the material’s potential.
Stanene is the name given by researchers to 2-D sheets of tin that are only one atom thick. A Stanford Univ. team predicts stanene would be the first topological insulator to demonstrate zero heat dissipation properties at room temperature, conducting charges around its edges without any loss. Experiments are underway to create the material in the laboratory. If successful, stanene will enhance devices being built under a DARPA program.
Researchers have created a new type of molecular motor made of DNA and demonstrated its potential by using it to transport a nanoparticle along the length of a carbon nanotube. The design was inspired by natural biological motors that have evolved to perform specific tasks critical to the function of cells.
Ribbons of ultrathin graphene combined with polyurethane paint meant for cars is just right for deicing sensitive military radar domes, according to scientists at Rice Univ. The Rice lab of chemist James Tour, in collaboration with Lockheed Martin, developed the compound to protect marine and airborne radars with a robust coating that is also transparent to radio frequencies.
Metal-organic frameworks (MOFs) are commanding considerable research attention because of their appetite for greenhouse gases. But now supramolecular organic frameworks (SOFs), held together by non-covalent bonds, have joined the field. Researchers have unveiled the first 2-D SOFs that self-assemble in solution, an important breakthrough that holds implications for sensing, separation technologies, and biomimetics.
Medical diagnostics seeks to learn early on whether a serious disease is developing or what its course will be. In many cases, treacherous molecules are present only in trace amounts, however. Researchers in Germany have come up with a new method of detection which has allowed them to notice the presence of only 17 dye molecules. The highly sensitive method might one day be used to scan a tiny drop of blood for potential diseases.
Scientists from the Hamburg Center for Free-Electron Laser Science have devised a novel way to boil water in less than a trillionth of a second. The theoretical concept, which uses terahertz radiation but has not yet been demonstrated in practice, could heat a small amount of water by as much as 600 C in just half a picosecond.
The goal of fabricating fixed-size one-dimensional silica structures and being able to precisely control the diameter during growth has long eluded scientists. Now, Oak Ridge National Laboratory researchers Panos Datskos and Jaswinder Sharma have demonstrated what they describe as the addressable local control of diameter of each segment of the silica rod.
The same tiny cellulose crystals that give trees and plants their high strength, light weight and resilience, have now been shown to have the stiffness of steel. Calculations using precise models based on the atomic structure of cellulose show the crystals have a stiffness of 206 gigapascals, which is comparable to steel.
Physicists in Germany have developed a “planet-satellite model” to precisely connect and arrange nanoparticles in 3-D structures. Inspired by the photosystems of plants and algae, these artificial nanoassemblies of DNA strands might in the future serve to collect and convert energy.
Scientists working to advance imaging useful to medicine and security are capitalizing on the same phenomenon behind the lingering "ghost" image that appeared on old television screens. A team of researchers has created a way to control the length of time light from a luminescent nanocrystal lingers, adding a new dimension of time to color and brightness in optical detection technology.
Today’s fuel cells require costly platinum as a catalyst for the reaction that forms water from hydrogen and oxygen. A research team inspired by nature to develop an alternative catalyst has designed a material consisting of organic molecules as well as iron or manganese on a metallic substrate. These materials are less costly and more easily available than platinum.
A Duke Univ. research team has developed a better recipe for synthetic replacement cartilage in joints. Combining two innovative technologies, the team found a way to create artificial replacement tissue that mimics both the strength and suppleness of native cartilage. Articular cartilage is the tissue on the ends of bones where they meet at joints in the body.
Strategies to manipulate light and sound go back to the first spherical glass bead and the pounding of the first hollow log. But their full potential is only just becoming apparent, according to a review by materials scientists at Rice Univ. and their colleagues. New abilities to corral light and sound from the macroscale to the nanoscale with structured polymers could deliver profound changes in the way we live.
A research team in France has invented an adhesion method that creates a strong bond between two gels by spreading on their surface a solution containing nanoparticles. Until now, there was no entirely satisfactory method of obtaining adhesion between two gels or two biological tissues. The bond is resistant to water and uses no polymers or chemical reactions.
One of the most difficult hurdles in adapting carbon nanotubes to industrial purposes is processing the carbon nanotubes into smaller forms to allow them to more easily disperse. However, recent research has managed to cut carbon nanotubes into the smallest dimensions ever to overcome this problem.
There are examples of art imitating nature all around us, from Monet to Chihuly, but when physicist Latika Menon peered under the electron microscope last fall, she discovered the exact opposite in gallium nitride nanowires that bore an uncanny resemblance to artistic pots found in her native India. Menon has begun to control these shapes, which will make the nanowires significantly more promising for use in advanced devices.