It’s estimated that more than half of U.S. energy is wasted as heat. Mostly, this waste heat simply escapes into the air. But that’s beginning to change, thanks to thermoelectric innovators such as Massachusetts Institute of Technology’s Gang Chen. Thermoelectric materials convert temperature differences into electric voltage.
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.
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.
The engineering of functional systems at the molecular scale, nanotechnology refers to the applied part of nanoscience which typically includes the engineering to control, manipulate and structure matter at an atomically small scale. Nanotechnology as a field is nothing less than diverse, ranging from extensions of conventional device physics to new approaches based upon molecular self-assembly.
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.
There’s a new wave of sound on the horizon carrying with it a broad scope of tantalizing potential applications, including advanced ultrasonic imaging and therapy, and acoustic cloaking, levitation and particle manipulation. Researchers with Lawrence Berkeley National Laboratory have developed a technique for generating acoustic bottles in open air that can bend the paths of sound waves along prescribed convex trajectories.
In a recent paper, a team at Stanford Univ. which includes materials science expert Yi Cui and 2011 R&D Magazine Scientist of the Year Steven Chu report that they have taken a big step toward accomplishing what battery designers have been trying to do for decades: design a pure lithium anode.
Long before humans figured out how to create colors, nature had already perfected the process. Now scientists are tapping into those secrets to develop a more environmentally friendly way to make colored plastics. Their paper on using structure—or the shapes and architectures of materials—rather than dyes, to produce color appears in Nano Letters.
An Israeli and German research team have succeeded in creating a tiny screw-shaped propeller that can move in a gel-like fluid, mimicking the environment inside a living organism. The filament that makes up the propeller, made of silica and nickel, is only 70 nm in diameter. The entire propeller is just 400 nm long.
Tough, ultra-light foam of atom-thick sheets can be made to any size and shape through a chemical process invented at Rice Univ. In microscopic images, the foam dubbed “GO-0.5BN” looks like a nanoscale building, with floors and walls that reinforce each other. The structure consists of a pair of 2-D materials: floors and walls of graphene oxide that self-assemble with the assistance of hexagonal boron nitride platelets.
A team of researchers has created a new way of manufacturing microstructured surfaces that have novel 3-D textures. These surfaces, made by self-assembly of carbon nanotubes, could exhibit a variety of useful properties—including controllable mechanical stiffness and strength, or the ability to repel water in a certain direction.
A new study has investigated the effects of small but finite inertia on the propulsion of micro- and nano-scale swimming machines. Scientists have found that the direction of propulsion made possible by such inertia is opposite to that induced by a viscoelastic fluid. The findings could help to optimize the design of swimming machines to improve their mobility in medical applications.
A new method of building materials using light, developed by researchers at the Univ. of Cambridge, could one day enable technologies that are often considered the realm of science fiction. Although cloaked starships won’t be a reality for quite some time, the technique which researchers have developed for constructing materials with building blocks a few nanometers across can be used to control the way that light flies through them.
Scientists at SLAC National Accelerator Laboratory have invented a customizable chemical etching process that can be used to manufacture high-performance focusing devices for the brightest x-ray sources on the planet, as well as to make other nanoscale structures such as biosensors and battery electrodes.
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.
By colliding ultra-small gold particles with a surface and analyzing the resulting fragments, a trio of scientists at Pacific Northwest National Laboratory discovered how and why the particles break. This information is important for controlling the synthesis of these tiny building blocks that are of interest to catalysis, energy conversion and storage, and chemical sensing.
Vibrate a solution of rod-shaped metal nanoparticles in water with ultrasound and they'll spin around their long axes like tiny drill bits. Why? No one yet knows exactly. But researchers at the NIST have clocked their speed, and it's fast. At up to 150,000 revolutions per minute, these nanomotors rotate 10 times faster than any nanoscale object submerged in liquid ever reported.
Applying just the right amount of tension to a chain of carbon atoms can turn it from a metallic conductor to an insulator, according to Rice Univ. scientists. Stretching the material known as carbyne by just 3% can begin to change its properties in ways that engineers might find useful for mechanically activated nanoscale electronics and optics.
A special class of tiny gold particles can easily slip through cell membranes, making them good candidates to deliver drugs directly to target cells. A new study from Massachusetts Institute of Technology materials scientists reveals that these nanoparticles enter cells by taking advantage of a route normally used in vesicle-vesicle fusion, a crucial process that allows signal transmission between neurons.
A new material structure developed at Massachusetts Institute of Technology generates steam by soaking up the sun. The structure—a layer of graphite flakes and an underlying carbon foam—is a porous, insulating material structure that floats on water. When sunlight hits the structure’s surface, it creates a hotspot in the graphite, drawing water up through the material’s pores, where it evaporates as steam.
New technology under development at the Univ. of California, Berkeley could soon give bomb-sniffing dogs some serious competition. A team of researchers has found a way to dramatically increase the sensitivity of a light-based plasmon sensor to detect incredibly minute concentrations of explosives.
Researchers at the Univ. of Illinois at Urbana-Champaign have demonstrated that an array of novel gold, pillar-bowtie nanoantennas (pBNAs) can be used like traditional photographic film to record light for distances that are much smaller than the wavelength of light (for example, distances less than ~600 nm for red light). A standard optical microscope acts as a “nanocamera” whereas the pBNAs are the analogous film.
A team including scientists from Spain and from IBM Research in Switzerland have published work which describes an extremely simple method to obtain high quality nanographenes from easily available organic compounds. This method is based on the reactivity of a group of molecules named arynes, which can act as "molecular glue" to paste graphene fragments together.
Scientists in Texas have created a unique sensor that amplifies the optical signature of molecules by about 100 billion times. The new imaging method uses a form of Raman spectroscopy in combination with an intricate but mass reproducible optical amplifier. Newly published tests found the device could accurately identify the composition and structure of individual molecules containing fewer than 20 atoms.