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Hydrogen fuel derived from the sea could be an abundant and sustainable alternative to fossil fuels, but the potential power source has been limited by technical challenges, including how to practically harvest it. Now, researchers at the University of Central Florida have designed, for the first time, a nanoscale material that can efficiently split seawater into oxygen and hydrogen.
A team of German and U.S. researchers has detected the rolling movement of a nano-acoustic wave predicted by the famous physicist and Nobel prize-winner Lord Rayleigh in 1885. The researchers used a nanowire inside which electrons are forced onto circular paths by the spin of the acoustic wave. This phenomenon can find applications in acoustic quantum technologies or in so-called phononic components, which are used to control the propagation of acoustic waves.
Researchers have revealed the correlated structural and chemical evolution of silicon and the solid-electrolyte interplay that forms in all batteries and makes them work. The researchers grew a “forest” of silicon nanowires on a stainless steel disk as the anode for a battery and found that the electrolyte penetrates silicon everywhere, forming pockets of solid-electrolyte interplay that disrupt electron pathways. This process disconnects isolated islands of silicon in the anode that cannot contribute to battery capacity.
Researchers at North Carolina State University have demonstrated a low-cost technique for retrieving nanowires from electronic devices that have reached the end of their utility, and then using those nanowires in new devices. The work is a step toward more sustainable electronics.
Researchers at Cornell University have developed nanostructures that enable record-breaking conversion of laser pulses into high-harmonic generation, paving the way for new scientific tools for high-resolution imaging and studying physical processes that occur at the scale of an attosecond – one quintillionth of a second. The nanostructures created by the team make up an ultrathin resonant gallium-phosphide metasurface that overcomes many of the usual problems associated with high-harmonic generation in gases and solids.
Some materials used in aerospace applications can degrade and erode with prolonged exposure to atomic oxygen, ultraviolet radiation, extreme temperature cycling, and micrometeoroids in outer space. Introducing self-healing materials that incorporate specially designed nanoparticles and microparticles could provide a more durable solution for space structures. Several labs at the University of Illinois Urbana-Champaign have worked together to meet this challenge and, for the first time, have sent self-healing materials into orbit for testing at the International Space Station National Laboratory.
Engineers at Washington University in St. Louis have made a new fiber that is stronger than steel and tougher than Kevlar. A problem associated with artificial spider silk fiber is the need to create beta-nanocrystals, a main component of natural spider silk, which contributes to its strength. So, the engineers redesigned the silk sequence by introducing amyloid sequences that have a high tendency to form beta-nanocrystals.
Engineers at Washington University in St. Louis have used nanoparticles to manipulate the electrical activity of neurons in the brain and of heart muscle cells. The noninvasive technology inhibits the electrical activity of neurons using polydopamine nanoparticles and near-infrared light. The negatively charged nanoparticles, which selectively bind to neurons, absorb near-infrared light that creates heat, which is then transferred to the neurons, inhibiting their electrical activity. By contrast, when applied to heart muscle cells, the technology excited them, showing that the excitability in cells can be either increased or decreased, depending on their type.
Designing new nanomaterials is an important aspect of developing next-generation devices used in electronics, sensors, energy harvesting and storage, and optical detectors. To design such nanomaterials, researchers create interatomic potentials through atomistic modeling, a computational approach that predicts how these materials behave by accounting for their properties at the smallest level. Now, researchers at Northwestern University have developed a new framework using machine learning that improves the accuracy of interatomic potentials in new materials design. The findings could lead to more accurate predictions of how new materials transfer heat, deform, and fail at the atomic scale.
Researchers have discovered a "layer" Hall effect in a solid state chip constructed of antiferromagnetic manganese bismuth telluride, a finding that signals a much sought-after topological Axion insulating state. Researchers believe that when it is fully understood, topological Axion insulators can be used to make semiconductors with potential applications in electronic devices. The material (antiferromagnetic manganese bismuth telluride) forms a two-dimensional layered crystal structure, which allowed the researchers to mechanically exfoliate atom-thick flakes using cellophane tape. Thin flake structures with even numbers of layers were proposed to be an Axion insulator.
