Highly purified crystals that split light with precision are valued in specialized optics. But photonic crystals are difficult to make with current techniques, namely electron beam etching. Researchers at Princeton and Columbia universities have proposed a new method derived from colloidal suspensions that could allow scientists to customize and grow optimal crystals with relative ease.
By “drawing” micropatterns on nanomaterials using...
The yield so far is small, but chemists at the...
Researchers at the Univ. of California, Riverside have used a quartz-rich material to fabricate a lithium-ion battery that outperforms the current industry standard by three times. This key material? Sand. Through a heating process with salt and magnesium, the scientists created a porous nano-silicon sponge that greatly increases active surface area.
Researchers at Pacific Northwest National Laboratory have developed a porous material to replace the graphite traditionally used in a battery's electrodes. Made from silicon, which has more than 10 times the energy storage capacity of graphite, the sponge-like material can help lithium-ion batteries store more energy and run longer on a single charge.
The light-warping structures known as metamaterials have a new trick in their ever-expanding repertoire. Researchers at NIST have built a silver, glass and chromium nanostructure that can all but stop visible light cold in one direction while giving it a pass in the other. The device could someday play a role in optical information processing and in novel biosensing devices.
Materials science experts in North Carolina and China collaborated on work that drew inspiration from the structure of bones and bamboo. The team has found that by gradually changing the internal structure of metals, stronger, tougher materials can be created and customized for a wide variety of applications, from body armor to automobile parts. The gradient structure concept works on numerous metals, including stainless steel and nickel.
Computer simulation has shown Stanford Univ. engineers how to make a crystal that would toggle like a light switch between conductive and non-conductive structures. This flexible, switchable lattice, just three atoms thick, can be turned on or off by mechanically pushing or pulling, and could lead to flexible electronic materials.
A proposed hybrid quantum processor for a future quantum computer uses trapped atoms as the memory and superconducting qubits as the processor. The concept requires, however, an optical trap that is able to work well with superconductors, which don’t like magnetic fields or high optical power. Joint Quantum Institute scientists believe they’ve developed an effective method for creating these ultra-high transmission optical nanofibers.
Titanium dioxide nanoparticles show great promise as optical encapsulants or fillers for tunable refractive index coatings. However, they've been largely shunned because they’ve been difficult and expensive to make. Scientists at Sandia National Laboratories have now come up with an inexpensive way to synthesize properly sized titanium dioxide nanoparticles and is seeking partners who can demonstrate the process at industrial scale.
Superlyophobic surfaces are simultaneously repellant for almost any liquid and exhibit high contact angles and low flow resist. But the demanding and usually expensive fabrication remains a bottleneck for further development. Researchers in Shenzhen, China, however, have now formulated a facile and inexpensive microfabrication method that uses polymers to help transfer the superlyophobic structures to curable materials.
A dash of clay, a dab of fiber from crab shells, and a dollop of DNA: This strange group of materials are actually the ingredients of promising green fire retardants invented by researchers at NIST. Applied to polyurethane foam, the bio-based coatings greatly reduced the flammability of the common furniture padding after it was exposed to an open flame.
Haydale, a U.K.-based developer of a unique plasma functionalization process for nanomaterials, has announced the publication of research showing its functionalized graphene nanoplatelets significantly improve the nanoscale reinforcement of resin. The report states a greater than two times increase in tensile strength and modulus of an epoxy composite using this technology.
Bang & Olufsen is working with scientists in Denmark to develop a method for creating white aluminium surfaces. This has been exceedingly difficult for manufacturers because the existing technology used to color aluminium cannot be used to produce the color white because the molecules used to create “white” are too big. Rather than use pigments, then, researchers have a way to make it become white during the process.
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.
In response to persistent haze and concerns about its health effects, scientists in Hong Kong have developed a simple face mask which can block out suspended particles. The nanofiber technology can filter ultra-fine pollutants that have yet been picked up by air quality monitors. These particles can measure 1 micrometer or less.
Researchers in Australia have created a micrometer thin film with record-breaking optical nonlinearity suitable for high-performance integrated photonic devices. To create the thin film the researchers spin coated graphene oxide solution to a glass surface. Using a laser as a pen they created microstructures on the graphene oxide film to tune the nonlinearity of the material.
While flexible gadgets such as “electronic skin” and roll-up touch screens are moving ever closer to reality, their would-be power sources are either too wimpy or too stiff. But that’s changing fast. Scientists have developed a new device that’s far thinner than paper, can flex and bend, and store enough energy to provide critical back-up power for portable electronics.
Super-resolution microscopy has allowed optical imaging of objects with dimensions smaller than the diffraction limit. Researchers studying a type of material called supramolecular polymers have used this type of imaging to develop a new technique that allows them study molecular self-assembly at an unprecedented level of detail.
Of all the electricity generated in the U.S., more than quarter is consumed by lighting. In 2010, North Carolina’s RTI International launched a new product, NLite, intended to help alleviate this burden by improving the reflectance performance of power-intensive lighting devices such as luminaires and liquid crystal displays. The technology, based on nanofiber reflectance polymers, won a 2011 R&D 100 Award.
Researchers in Spain have developed a highly fluorescent hybrid material that changes color depending on the polarization of the light that it is illuminated by. They achieved this with a perfect fit between an inorganic nanostructure and dye molecules.
Of late, engineers have been paying more and more attention to nature’s efficiencies, such as the Lotus effect, which describes the way the Lotus plant uses hydrophobic surfaces to survive in muddy swamps. A researcher at Virginia Tech has developed a simpler two-step application process to create a superhydrophobic copper surface that leverages the Lotus effect.
Researchers in Ireland have used a simple method for transforming flakes of graphite into defect-free graphene using commercially available tools, such as high-shear mixers. They demonstrated that the process could be scaled up to produce hundreds of liters or more, and they have partnered with Thomas Swan Ltd. to develop two new graphene-based products for the marketplace.
Researchers have produced a stable porous membrane that is thinner than a single nanometer. The membrane consists of two layers of graphene on which have been etched tiny pores of a precisely defined size. Extremely light and breathable, the new material could help enable a new generation of ultra-rapid filters or functional waterproof clothing.
Researchers in Pennsylvania and Texas have shown the ability to grow high quality, single-layer materials one on top of the other using chemical vapor deposition. This highly scalable technique, often used in the semiconductor industry, can produce materials with unique properties that could be applied to solar cells, ultracapacitors for energy storage, or advanced transistors for energy efficient electronics, among many other applications.
Chemists have found that cellulose, the most abundant organic polymer on Earth, can be heated in a furnace in the presence of ammonia and turned into the building blocks for supercapacitors. The new process produces nitrogen-doped, nanoporous carbon membranes, which act as the electrodes of a supercapacitor. The only byproduct is methane, which could be used immediately as a fuel or for other purposes.
Using an acoustic metadevice that can influence the acoustic space and can control any of the ways in which waves travel, engineers have demonstrated, for the first time, that it is possible to dynamically alter the geometry of a 3-D colloidal crystal in real time. The crystals designed in the study, called metamaterials, are artificially structured materials that extend the properties of naturally occurring materials and compounds.
Researchers in Sweden have designed a paper filter which is capable of removing virus particles with the efficiency matching that of the best industrial virus filters. The paper filter, which is manufactured according to traditional paper making processes, consists of 100% high purity cellulose nanofibers directly derived from nature.
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