When studying extremely fast reactions in ultra-thin materials, two measurements are better than one. A new research tool invented by researchers at Lawrence Livermore National Laboratory (LLNL), Johns Hopkins Univ. and NIST captures information about both temperature and crystal structure during extremely fast reactions in thin-film materials.
It’s a well-known phenomenon in electronics: Shining light on a semiconductor, such as the silicon used in computer chips and solar cells, will make it more conductive. But now researchers have discovered that in a special semiconductor, light can have the opposite effect, making the material less conductive instead. This new mechanism of photoconduction could lead to next-generation excitonic devices.
Nanoparticles could revolutionize the medical industry, but they must first target a specific region in the body, be trackable, and perform their function at the right moment. Researchers in Japan have made progress in this direction with a new type of nanomaterial: the nanosheet. Specifically, they have designed a strong, stable and optically traceable smart 2-D material that responds to pH, or the acidity or basicity of its environment.
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.
As tech company LG demonstrated this summer with the unveiling of its 18-in flexible screen, the next generation of roll-up displays is tantalizingly close. Researchers are now reporting a new, inexpensive and simple way to make transparent, flexible transistors that could help bring roll-up smartphones with see-through displays and other bendable gadgets to consumers in just a few years.
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.
Researchers at Oak Ridge National Laboratory got a surprise when they built a highly ordered lattice by layering thin films containing lanthanum, strontium, oxygen and iron. Although each layer had an intrinsically nonpolar distribution of electrical charges, the lattice had an asymmetric distribution of charges.
Anyone who has ever had a glass of fizzy soda knows that bubbles can throw tiny particles into the air. But in a finding with wide industrial applications, Princeton Univ. researchers have demonstrated that the bursting bubbles push some particles down into the liquid as well.
Wrapping wound dressings around fingers and toes can be tricky, but for burn victims, guarding them against infection is critical. At the National Meeting & Exposition of the American Chemical Society scientists have reported the development of new ultra-thin coatings called nanosheets that can cling to the body's contours and keep bacteria at bay. The super-thin sheets have been tested on mice and could help transform burn treatment.
By carefully controlling the position of an atomic-scale diamond defect within a volume smaller than what some viruses would fill, researchers have cleared a path toward better quantum computers and nanoscale sensors. These diamond defects are attractive candidates for qubits, the quantum equivalent of a computing bit, and accurate positioning is key to using them to store and transmit information.
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.
About one in four older adults suffers from chronic pain. Many of those people take medication, usually as pills. But this is not an ideal way of treating pain: Patients must take medicine frequently, and can suffer side effects, since the contents of pills spread through the bloodstream to the whole body. Now researchers have refined a technique that could enable pain medication to be released directly to specific parts of the body.
By “drawing” micropatterns on nanomaterials using a focused laser beam, scientists in Singapore have modifed properties of nanomaterials for effective photonic and optoelectronic applications. Their method increased electrical conductivity and photoconductivity of the modified molybdenum disulfide material by more than 10 times and about five times respectively.
The addition of elements to the surface of graphene can modify the material’s physical and chemical properties, potentially extending the range of possible applications. Recently performed theoretical calculations at RIKEN in Japan show that the addition of oxygen to graphene on copper substrates results in enhanced functionalization. The resulting structure, known as an enolate, make support applications that require catalytic response.
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.
SiEnergy Systems, an Allied Minds company commercializing low temperature thin film solid oxide fuel cell (SOFC) technology from Harvard University, has announced that it has been selected for $2.65 million in funding from Advanced Research Projects Agency-Energy (ARPA-E). SiEnergy has develop innovative and unique hybrid electrochemical system that performs as both fuel cell and battery.
According to researchers, a simple, scalable method of making strong, stretchable graphene oxide fibers that are easily scrolled into yarns and have strengths approaching that of Kevlar is possible. An international collaboration has recently produced graphene oxide yarn fibers much stronger than other carbon fibers.
In semiconductor-based components, high mobility of charge-carrying particles is important. In organic materials, however, it is uncertain to what degree the molecular order within the thin films affects the mobility and transport of charge carriers. Using a new imaging method, researchers have shown that thin-film organic semiconductors contain regions of structural disorder that could inhibit the transport of charge and limit efficiency.
Normally, keeping glass clean and clear depends on repelling or wiping away water droplets. Or a coating attached to help do this. But researchers in Singapore have discovered that doing just the opposite, collecting water, is the key to keeping a surface clear. Their superhydrophilic coating attracts water to create a uniform, thin, transparent layer.
Scientists seeking ways to engineer the assembly of tiny particles measuring just billionths of a meter have achieved a new first: the formation of a single layer of nanoparticles on a liquid surface where the properties of the layer can be easily switched. Understanding the assembly of such nanostructured thin films could lead to the design of new kinds of membranes with a variable mechanical response for a wide range of applications.
The days of self-assembling nanoparticles taking hours to form a film over a microscopic-sized wafer are over. Researchers with Lawrence Berkeley National Laboratory have devised a technique whereby self-assembling nanoparticle arrays can form a highly ordered thin film over macroscopic distances in one minute.
Essential oils have boomed in popularity as people seek alternatives to replace their synthetic cleaning products, anti-mosquito sprays and medicines. Now scientists are tapping them as candidates to preserve food in a more consumer-friendly way. A study from the Journal of Agricultural and Food Chemistry reports the development of new edible films containing oils from clove and oregano that preserve bread longer than commercial additives.
In the wake of recent offshore oil spills, and with the growing popularity of “fracking”—in which water is used to release oil and gas from shale—there’s a need for easy, quick ways to separate oil and water. Now, scientists have developed coatings that can do just that. Their report on the materials, which also could stop surfaces from getting foggy and dirty, appears in ACS Applied Materials & Interfaces.
Saudi Arabian-based petrochemical company SABIC and Cima NanoTech have announced the joint development of a new transparent conductive polycarbonate film. The collaboration leverages both Cima NanoTech’s proprietary SANTE nanoparticle technology and SABIC’s LEXAN film to produce a film that outperforms indium tin oxide by a factor of ten.
Researchers in Spain have introduced a platform technology based on optical antennas for trapping and controlling light with graphene. Their experiments show that the dramatically squeezed graphene-guided light can be focused and bent, following the fundamental principles of conventional optics. The work opens new opportunities for smaller and faster photonic devices and circuits.
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