Graphene’s exotic properties can be tailored by cutting large sheets down to ribbons of specific lengths and edge configurations. But this “top-down” fabrication approach is not yet practical, because current lithographic techniques always produce defects. Now, scientists from the U.S. and Japan have discovered a new “bottom-up” self-assembly method for producing defect-free graphene nanoribbons with periodic zigzag-edge regions.
Individuals in industrial associations, educational institutions and government organizations who are interested in composites, or materials made from constituent materials with different physical or chemical properties, now have free, 24/7 access to simulation tools through an online community with offices in the Purdue Research Park.
The world’s first “solar battery”, invented by researchers at Ohio State Univ., is a battery and a solar cell combined into one hybrid device. Key to the innovation is a mesh solar panel, which allows air to enter the battery, and a special process for transferring electrons between the solar panel and the battery electrode. Inside the device, light and oxygen enable different parts of the chemical reactions that charge the battery.
Nanostructures of virtually any possible shape can now be made using a combination of techniques developed to exploit the unique properties of so-called perovskites. The group based in the Netherlands, developed a pulsed laser deposition technique to create patterns in ultra thin layers, one atomic layer at a time. The perovskites’ crystal structure is undamaged by this soft lithography technique, maintaining electrical conductivity.
In a rare case of having their cake and eating it too, scientists from NIST and other institutions have developed a toolset that allows them to explore the complex interior of tiny, multi-layered batteries they devised. It provides insight into the batteries’ performance without destroying them, which results in both a useful probe for scientists and a potential power source for micromachines.
Diamonds aren’t just a girl’s best friend, they’re also R&D’s best friend—or at least a new acquaintance. Many laboratories and companies are embracing synthetic diamond for its elevated super properties in applications ranging from analytical instruments and biomedical sensors to electronics and lasers to water purification.
A common complaints about solar power is that solar panels are still too expensive. Efforts at making them more efficient or longer-lasting have been limited. A new method developed in Okinawa could solve the expense problem: A hybrid form of deposition is being used to create perovskite solar cells from a mixture of inexpensive organic and inorganic raw materials, eliminating the need for expensive crystallized silicon.
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.
Glenn Johnson, CEO of BlueVine Graphene Industries Inc., said many of the methodologies being utilized to produce graphene today are not easily scalable and require numerous post-processing steps to use it in functional applications. He said his company has developed a way to scale graphene production using a roll-to-roll chemical vapor deposition process.
A new method for controllably constructing precise inter-nanotube junctions and structures in carbon nanotube (CNT) arrays, Northeastern Univ. researchers say, is facile and easily scalable. It will allow them to tailor the physical properties of nanotube networks for use in applications ranging from electronic devices to CNT-reinforced composite materials found in everything from cars to sports equipment.
Imagine a balloon that could float without using any lighter-than-air gas. Instead, it could simply have all of its air sucked out while maintaining its filled shape. Such a material might be possible with a new method developed at the California Institute of Technology that allows engineers to produce a ceramic that contains about 99.9% air yet is strong enough to recover its original shape after being smashed by more than 50%.
Artificial membranes mimicking those found in living organisms have many potential applications ranging from detecting bacterial contaminants in food to toxic pollution in the environment to dangerous diseases in people. Now a group of scientists in Chile has developed a way to create these delicate, ultra-thin constructs through a "dry" process, by evaporating two commercial, off-the-shelf chemicals onto silicon surfaces.
A new concept in metallic alloy design called “high-entropy alloys” has yielded a multiple-element material that tests out as one of the toughest on record. But, unlike most materials, the toughness as well as the strength and ductility of this alloy, which contains five major elements, actually improves at cryogenic temperatures.
As a semiconductor material, germanium is superior to silicon. But it is more expensive to process for widespread use in batteries, solar cells, transistors and other applications. Researchers in Missouri have now developed what they call “a simple, one-step method” to grow nanowires of germanium from an aqueous solution. Their process could make it more feasible to use germanium in lithium-ion batteries.
Polymers come with a range of properties dictated by their chemical composition and geometrical arrangement. Yasuyuki Tezuka and his team at Tokyo Institute of Technology have now applied an approach to synthesize a new type of multicyclic polymer geometry. While mathematicians are interested because these structures have not been realized before, the geometry studies also provide insights for chemists.
Materials like solid gels and porous foams are used for padding and cushioning, but each has its own advantages and limitations. To overcome limitations, a team from Lawrence Livermore National Laboratory has found a way to design and fabricate, at the microscale, new cushioning materials with a broad range of programmable properties and behaviors that exceed the limitations of the material's composition through 3-D printing.
Researchers in Europe have succeeded for the first time in growing single-walled carbon nanotubes with only a single, prespecified structure. The nanotubes thereby have identical electronic properties. The decisive trick was producing the carbon nanotube from custom-made organic precursor molecules.
A team of materials chemists, polymer scientists, device physicists and others at the Univ. of Massachusetts Amherst report a breakthrough technique for controlling molecular assembly of nanoparticles over multiple length scales that should allow faster, cheaper, more ecologically friendly manufacture of organic photovoltaics and other electronic devices.
Using a relatively straightforward technique, a team of NIST researchers has created what may be the most highly enriched silicon currently being produced. The material is more than 99.9999% pure silicon-28, with less than 1 part per million (ppm) of the problematic isotope silicon-29. Many quantum computing schemes require isotopically pure silicon, for example to act as a substrate for qubits.
For the first time, researchers have succeeded in "growing" single-wall carbon nanotubes (CNT) with a single predefined structure, and hence with identical electronic properties. The method involved self-assembly of tailor-made organic precursor molecules on a platinum surface. In the future, carbon nanotubes of this kind may be used in ultra-sensitive light detectors and ultra-small transistors.
The Facilities 450mm Consortium (F450C), a partnership of leading nanoelectronics facility companies guiding the effort to design and build the next-generation 450mm computer chip fabrication facilities, has announced it has again increased in size, naming Pfeiffer Vacuum as the twelfth member company to join the consortium.
Traditional lithography is based on a simple principle: Oil and water don’t mix. The method, first developed by an actor in Bavaria in 1796, used a smooth piece of limestone on which an oil-based image was drawn and overlayed with gum arabic in water. During printing, the ink was attracted to the oil, and was repelled by the gum.
Most MEMS are made primarily of silicon for reasons of convenience, but they wear out quickly due to friction and they are not biocompatible. Researchers at Argonne National Laboratory and a handful of other institutions around the world have directed their focus on ultrananocrystalline diamond (UNCD), which are smooth and wear-resistant diamond thin films. Recent work opens the door to using diamond for fabricating advanced MEMS devices.
Like the perfect sandwich, a perfectly engineered thin film for electronics requires not only the right ingredients, but also just the right thickness of each ingredient in the desired order, down to individual layers of atoms. In recent experiments Cornell Univ. researchers found a major difference between assembling atomically precise oxide films and the conventional layer-by-layer “sandwich making” of molecular beam epitaxy.
A group of scientists from South Korea have converted used-cigarette butts into a high-performing material that could be integrated into computers, handheld devices, electrical vehicles and wind turbines to store energy. In published research, the team has demonstrated that the cellulose acetate fibres that cigarette filters are mostly composed of could be transformed into a carbon-based material using pyrolysis.
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