Although the potential uses for graphene seem limitless, there has been no easy way to scale up from microscopic to large-scale applications without introducing defects. Researchers in Chicago and Korea have recently developed a supersonic spray system that produces very small droplets of graphene which disperse evenly, evaporate rapidly, and reduce aggregation tendencies. And, to the researchers’ surprise, it also eliminates defects.
Using a doped-graphene matrix to slow down and then trap atoms of the precious metal osmium, researchers in the U.K. have shown the ability to control and quantify the growth of metal-crystals. When the trapped atoms come into contact with further osmium atoms they bind together, eventually growing into 3-D metal-crystals. They have called this new technique nanocrystallometry.
Soon after graphene’s isolation, early research already showed that lithium batteries with graphene in their electrodes had a greater capacity and lifespan than standard designs. At the Univ. of Manchester, U.K., where graphene was first isolated, researchers are working with more than 30 companies to advance technology in graphene-enabled energy storage, particularly in the area of lithium-ion batteries and supercapacitors.
They are 3-D and yet single-sided: Moebius strips. These twisted objects have only one side and one edge. Using this iconic form, an international team of scientists has succeeded in designing the world’s first “triply” twisted molecule. Because of their peculiar quantum mechanical properties these structures are interesting for applications in molecular electronics and optoelectronics.
Fancy Erector Set? Nope. The elaborate fractal structure shown at left is many, many times smaller than that and is certainly not child's play. It’s the latest example of a fractal nanotruss—nano because the structures are made up of members that are as thin as 5 nm; truss because they are carefully architected structures that might one day be used in structural engineering materials.
In response to requests from the semiconductor industry, a team of researchers at the Physical Measurement Laboratory has demonstrated that atomic force microscope probe tips made from its near-perfect gallium nitride nanowires are superior in many respects to standard silicon or platinum tips. They also found a way to use the tips as LEDs to illuminate sample regions while scanning.
Scientists at the U.S. Dept. of Energy’s Argonne National Laboratory have discovered a previously unknown phase in a class of superconductors called iron arsenides. This sheds light on a debate over the interactions between atoms and electrons that are responsible for their unusual superconductivity.
Images taken by Rice Univ. scientists show that some diamonds are not forever. The Rice researchers behind a new study that explains the creation of nanodiamonds in treated coal also show that some microscopic diamonds only last seconds before fading back into less-structured forms of carbon under the impact of an electron beam.
Graphene’s promise as a material for new kinds of electronic devices, among other uses, has led researchers around the world to study the material in search of new applications. But one of the biggest limitations to wider use of the strong, lightweight, highly conductive material has been the hurdle of fabrication on an industrial scale.
In recent work at Brookhaven National Laboratory, semiconductor quantum dots (QDs) have been combined with graphene to develop nanoscale photonic devices that can dramatically improve our ability to detect light. The research has demonstrated that the thickness of the organic molecule layer that typically surrounds the QDs is crucial in attaining sufficiently high efficiency of light/energy transfer into the graphene.
Researchers have found that a particular species of quantum dots that weren't commonly thought to blink, do. So what? Well, although the blinks are short, even brief fluctuations can result in efficiency losses that could cause trouble for using quantum dots to generate photons that move information around inside a quantum computer or between nodes of a future high-security internet based on quantum telecommunications.
Melanin—and specifically, the form called eumelanin—is the primary pigment that gives humans the coloring of their skin, hair and eyes. It protects the body from the hazards of ultraviolet and other radiation that can damage cells and lead to skin cancer, but the exact reason why the compound is so effective at blocking such a broad spectrum of sunlight has remained something of a mystery.
An international team of researchers have figured out a new way of storing and releasing hydrogen by making a unique crystal phase of a material containing lithium, boron and the key ingredient, hydrogen. To check how they could get the hydrogen back out of the material, the scientists heated it and found that it released hydrogen easily, quickly and only traces of unwanted by-products.
Although lubricants for machinery are widely used, almost no fundamental innovations for this type of product has been made in the last 20 years, according researchers in Germany who have been working on a new class of lubricating substance. Their new liquid crystalline lubricant enable nearly frictionless sliding because although it is a liquid, the molecules display directional properties like crystals do.
This gift from science just keeps on giving. Measurements taken at NIST show why a material already known to be good at separating components of natural gas also can do something trickier: help convert one chemical to another, a process called catalysis. The discovery is a rare example of a laboratory-made material easily performing a task that biology usually requires a complex series of steps to accomplish.
Photocatalysis is a promising route to convert solar energy into chemical fuels, or to split water into molecular hydrogen. But viable photocatalysts, or promoters, for these applications are scarce. A team of chemists in California has come up with a model to explain this promoting effect that could shift the focus in the search for substitutes of the metals, and help identify better promoters for photocatalysis in the near future.
Brigham Young Univ. engineering professors Julie Crockett and Dan Maynes have created a sloped channel that is super-hydrophobic, and causes water to bounce like a ball as it rolls down the ramp. Their recent study finds surfaces with a pattern of microscopic ridges or posts, combined with a hydrophobic coating, produces an even higher level of water resistance, depending on how the water hits the surface.
A team led by researchers from the Univ. of California, Los Angeles has developed a new process to control molecular growth within the "building block" components of inorganic materials. The method, which uses nanoparticles to organize the components during a critical phase of the manufacturing process, could lead to innovative new materials, such as self-lubricating bearings for engines.
Terahertz, or T-ray, range of the electromagnetic has rich promise for scientific applications, but instrumentation that can take advantage of these rays for imaging are still in progress. Univ. of Michigan researchers have recently made a breakthrough by converting terahertz light into sound using a compact, sensitive detector that operates at room temperature and is fabricated in an unusual manner.
Researchers at the Univ. of California, Riverside have developed a new nanometer scale ruthenium oxide anchored nanocarbon graphene foam architecture that improves the performance of supercapacitors. They found that the new structure could operate safely in aqueous electrolyte and deliver two times more energy and power compared to supercapacitors commercially available today.
A material called sodium manganese dioxide has shown promise for use in electrodes in rechargeable batteries. Now a team of researchers has produced the first detailed visualization—down to the level of individual atoms—of exactly how the material behaves during charging and discharging, in the process elucidating an exotic molecular state that may help in understanding superconductivity.
Scientists at IBM Research have used a new “computational chemistry” hybrid approach to accelerate the materials discovery process that couples laboratory experimentation with the use of high-performance computing. The new polymers are the first to demonstrate resistance to cracking, strength higher than bone, the ability to reform to their original shape (self-heal), and the ability to be completely recycled back to the starting material.
Graphene continues to reign as the next potential superstar material for the electronics industry, a slimmer, stronger and much faster electron conductor than silicon. With no natural energy bandgap, however, graphene’s superfast conductance can’t be switched off, a serious drawback for transistors and other electronic devices.
Using a material found in Silly Putty and surgical tubing, a group of researchers at the Univ. of California, Riverside Bourns College of Engineering have developed a new way to make lithium-ion batteries that will last three times longer between charges compared to the current industry standard. The innovation involves the development of silicon dioxide nanotube anodes.
Scientists at NASA Langley Research Center have developed a new material technology that alters a surface’s topography and chemistry to promote or mitigate adhesion. LaRC is holding a workshop and meeting on May 22 that explains how these newly available materials work to enhance or remove adhesion. Manufacturers and developers are welcome to attend.