[Image above] Credit: NIST
The newest Airbus and Boeing passenger jets flying today are made primarily from advanced composite materials such as carbon fiber reinforced plastic—extremely light, durable materials that reduce the overall weight of the plane by as much as 20% compared to aluminum-bodied planes. Such lightweight airframes translate directly to fuel savings, which is a major point in advanced composites’ favor.
Miniscule ribbons of graphene are highly sought-after building blocks for semiconductor devices because of their predicted electronic properties. But making these nanostructures has remained a challenge. Now, a team of researchers from China and Japan have devised a new method to make the structures in the lab.
There’s a new tool in the push to engineer rechargeable batteries that last longer and charge more quickly. An X-ray microscopy technique recently developed at Lawrence Berkeley National Lab has given scientists the ability to image nanoscale changes inside lithium-ion battery particles as they charge and discharge.
Solar cells based on cadmium and tellurium could move closer to theoretical levels of efficiency because of some sleuthing by researchers at the Oak Ridge National Lab. The team used advanced microscopy techniques to discover efficiency differences of crystalline structures of various mixtures of cadmium, tellurium, and selenium. In fact, selenium is an integral part of the formulation that resulted in a world record for solar cell efficiency.
Thanks to a reaction that resembles a sort of proton pinball game, a thin layer of moisture on the surface of a catalysts can improve the efficiency of fuel cells, devices used to transform chemical energy (a fuel like hydrogen, for example) directly into electricity without releasing greenhouse gases in emissions.
University of Wisconsin–Madison engineers have created high-performance, micro-scale solar cells that outshine comparable devices in key performance measures. The engineers created a densely packed, side-by-side array of miniature electrodes on top of transparent glass. The resulting structure separates light-harvesting and charge-conducting functions between the two components.
Researchers at the University of California, Riverside have created a new silicon-tin nanocomposite anode that could lead to lithium-ion batteries that can be charged and discharged more times before they reach the end of their useful lives. The longer-lasting batteries could be used in everything from handheld electronic devices to electric vehicles.
Hydrogen is widely regarded as a promising and clean alternative energy source. The traditional source of hydrogen (H2) for fuel cell use is water, which is split into H2 and oxygen (O2). But O2 is a low-value product. So, this week in ACS Central Science, researchers report a new approach and a new catalyst that can produce not just hydrogen but also valuable chemicals, including the most common ingredient in nail polish.
Using perovskites, a Korean research team at the Korea Advanced Institute of Science and Technology (KAIST) and Sungkyunkwan University developed a semi-transparent solar cell that is highly efficient and, additionally, functions very effectively as a thermal-mirror. The team has developed a top transparent electrode (TTE) that works well with perovskite solar cells.
Iowa State University scientists have developed a self-destructing, lithium-ion battery capable of delivering 2.5 V and dissolving or dissipating in 30 minutes when dropped in water. The battery can power a desktop calculator for about 15 minutes.
When seconds count, the right clothing matters. For the Rio Olympics, Nike used 3-D printing technology to develop small silicone protrusions for redirecting air flow around the runner. Body scanners helped Adidas design suits to keep swimmers in ideal form. Swiss cycling specialist Assos turned to wind tunnels to craft custom, form-fitting suits for the U.S. cycling team.
Researchers at UCLA found that calcium-silicate-hydrates, the binding phase that holds cement paste together, tend to dissolve at high-stress regions, and re-precipitate at low-stress regions. This is in correspondence with Le Chatelier’s principle, also known as the equilibrium law. “As a result of such dissolution-precipitation behavior, a macroscopic, time-dependent ‘creep’ deformation manifests.”
Bulk metallic glasses are metallic alloys whose neatly ordered atomic structure can be altered into an amorphous, non-crystalline structure. However, these alloys are complex, often containing five or six different elements, including expensive noble metals like gold or palladium—and scientists have no clue which combinations of elements will form them. Now, researchers have developed a method to predict which alloys may form a bulk metallic glass.
Known for their extraordinary surface area, a sugar packet equivalent of MOF provides a city block of area to absorb gas or catalyze reactions. But scientists recently uprooted the belief that these frameworks must be made from rigid starting materials. Their new design strategy transformed flexible polymers into 3-D porous structures by incorporating the flexible polymers into the synthesis of MOFs.
Glass-fiber cables transmit information over long distances at the speed of light. Once they have reached their destination, however, these optical signals have to be converted into electrical signals for subsequent processing in the computer. Karlsruhe Institute of Technology researchers have now developed a novel type of photodetector that needs far less space than conventional ones.
Fraunhofer scientists are manufacturing transistors and microchips that are only a few square millimeters in size out of the semiconductor material gallium nitride. “Due to its special crystal structure, the same voltages can be applied at even higher frequencies, leading to a better power and efficiency performance,” says one of the researchers.