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.
Optical metamaterials harness clouds of electrons...
Ever-shrinking electronic devices could get down...
Vertically aligned carbon nanofibers (VACNFs) are a commonly manufactured material, but conventional techniques for creating them have relied on the use of ammonia gas, which is toxic. Though it not costly, it is also not free, either. Researchers in North Carolina have demonstrated that VACNFs can be manufactured using ambient air, making the manufacturing process safer and less expensive.
Imagine a computer so efficient that it can recycle its own waste heat to produce electricity. While such an idea may seem far-fetched today, significant progress has already been made to realize these devices. Researchers at the Univ. of Utah have fabricated spintronics-based thin film devices which do just that, converting even minute waste heat into useful electricity.
Researchers at Tyndall National Institute in Ireland have produced the first ever atom-by-atom simulation of nanoscale film growth by atomic layer deposition (ALD), a thin-film technology used in the production of silicon chips. The accomplishment required the acquisition of the complete set of hundreds of ALD reactions at the quantum mechanical level.
New research shows that a remarkable defect in synthetic diamond produced by chemical vapor deposition allows researchers to measure, witness, and potentially manipulate electrons in a manner that could lead to new “quantum technology” for information processing.
To manufacture plastic parts with high-end surfaces, the entire forming tool is heated to 110 C using a technique known as variothermic tempering. To retrieve the finished plastic part, the mold must be cooled by up to 30 C, consuming lots of energy. Researchers have now developed a new kind of tempering technique that is up to 90% more energy efficient than variothermic tempering approaches.
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.
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.
Northwestern Univ. and Argonne National Laboratory scientists have recently overcome problems with growing graphene on chemically inert substrates, demonstrating the first growth of graphene on a single-crystal silver substrate. Their method could advance graphene-based optical devices and enable the interfacing of graphene with other two-dimensional materials.
Researchers in Germany are showing the way toward low-cost, industrial-scale manufacturing of a new family of electronic devices. Gas sensors that could be integrated into food packaging to gauge freshness, new types of solar cells and flexible transistors, and sensors that could be built into electronic skin: All can be made with carbon nanotubes, sprayed like ink onto flexible plastic sheets or other substrates.
By coating compact disks in photocatalytic compounds and spinning them to clean water, scientists in Taiwan have found a potential new use for old music CDs. The disks, equipped with tiny zinc oxide nanorods, are able to break down more than 95% of the contaminants in methyl orange dye, a benchmark organic compound for testing photocatalytic reactions.
A team from Cambridge Univ. in England has devised a simple technique to increase the density of nanotube forests grown on conductive supports about five times over previous methods. The new technique could one day help improve the performance of microelectronics in devices ranging from batteries to spacecraft.
A new method developed in Germany makes it possible to manufacture ultra-thin saw wires by placing diamond on carbon nanotubes. The new invention is designed to cut through silicon wafers with minimum kerf, or “sawdust”, loss that is the unavoidable result of current tools used in semiconductor wafer fabrication.
An international group of researchers from the U.S. and South Korea have discovered a groundbreaking technique in manufacturing nanostructures that has the potential to make electrical and optical devices smaller. The new patterning technology, called atomic layer lithography, based on a layering technique at the atomic level and relies on a surprising low-tech tool: Scotch Magic tape.
Engineers at NIST have developed a new technique for fabricating high aspect ratio 3-D nanostructures over large device areas using a combination of electron beam lithography, photolithography and resist spray coating. While it has long been possible to make complicated 3-D structures with many mask layers or expensive grayscale masks, the new technique enables researchers to etch features in two process steps without masks
In the future, carbon nanomembranes are expected to be able to filter out very fine material or even gases. Right now, basic research is concentrating on methods for the production of these nanomembranes. Using a new process a research team in Germany has produced 12 different carbon nanomembranes from a variety of starting materials.
Scientists at Switzerland have developed a new method for making antimicrobial surfaces that can eliminate bacteria under a minute. The breakthrough relies on a new sputtering technique that uses a highly ionized plasma to, for the first time, deposit antibacterial titanium oxide and copper films on 3-D polyester surfaces. This promotes the production of free radicals, which are powerful natural bactericides.
Flexible thin film solar cells that can be produced by roll-to-roll manufacturing are a highly promising route to cheap solar electricity. Researchers in Switzerland report that they have designed a low-cost cadmium telluride solar cell technology based on metal foil substrates. By doping the cells with cooper, they have elevated efficiency from 8 to 11.5%.
Electron beam (e-beam) lithography enables researchers to write very small patterns on large substrates with a high level of precision. In the Nano3 cleanroom facility at the Univ. of California, San Diego’s Qualcomm Institute, a new Vistec e-beam writer is helping to develop nanoscale transistors for integrated electronics, as well as neural probes for brain diagnostics.
Diffusion of sodium ions from the glass substrate is thought to be the primary cause of potential-induced degradation (PID) in crystalline silicon photovoltaic cells. A research institute and metals company in Japan have partnered to develop a thin film solution. The titanium oxide-based composite metal compound they have developed is inexpensive to produce and highly scalable.
Concentric hexagons of graphene grown in a furnace at Rice University represent the first time anyone has synthesized graphene nanoribbons on metal from the bottom up—atom by atom. As seen under a microscope, the layers brought onions to mind. Though flat graphene could never be like an onion, the name stuck.
A team led by John Hagopian, an optics engineer at NASA’s Goddard Space Flight Center, has recently demonstrated that it can grow a uniform layer of carbon nanotubes through the use of atomic layer deposition. The marriage of the two technologies now means that NASA can grow nanotubes on 3-D components, such as complex baffles and tubes commonly used in optical instruments.
A polymer thin film solar cell (PSC) produces electricity from sunlight by the photovoltaic effect. Though light and inexpensive, PSCs currently suffer from a lack of enough efficiency for large scale applications and they also have stability problems. Researches in Korea have designed and added multi-positional silica-coated silver nanoparticles that have greatly improved stability and performance of these cells.
Twenty years after the discovery of single-walled carbon nanotubes (SWNTs), a team of scientists in Finland, Russia, and Denmark has managed to control chirality in carbon nanotubes during their chemical vapor deposition synthesis. Because chirality defines the optical and electronic properties of nanotubes, the ability to predict it has been a longstanding goal for materials developers.
Wake Forest University's Organic Electronics group has developed an organic semiconductor “spray paint” that can be applied to large surface areas without losing electric conductivity. The new spray-deposition method has the advantages of drop casting, spin coating, and prior spray-on techniques: It can applied to large surfaces of any medium, retaining electrical performance.
Until recently, there has been no systematic way of evaluating how different anti-fog coatings perform under real-world conditions. A team of MIT researchers has developed such a testing method, and used it to find a coating that outperforms others not only in preventing foggy buildups, but also in maintaining good optical properties without distortion.
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