Phys.org November 11, 2021 Researchers at the University of Wisconsin developed a technique to convert ammonia to nitrogen gas using a metal catalyst containing ruthenium without added energy. The process can be harnessed to produce electricity, with protons and nitrogen gas as byproducts. In addition, the metal complex can be recycled through exposure to oxygen and used repeatedly, a much cleaner process than using carbon-based fuels. The new reaction avoids toxic byproducts. If the reaction were housed in a fuel cell where ammonia and ruthenium react at an electrode surface, it could cleanly produce electricity without the need for a […]
Tag Archives: Materials science
Ultra-thin film of magnetite optimized for spintronics
Phys.org November 17, 2021 Magnetite has physical properties which may make it useful for spintronics technology. However, it is difficult to fabricate magnetite with high crystallinity owing to the imperfection of the substrate surface. An international team of researchers (Japan, China) has developed a chemical polishing technique—known by its acronym CARE—to prepare an atomically flat and highly ordered magnesium oxide substrate. CARE treatment of the substrate enabled the thin film to undergo a temperature-dependent resistivity change—known as the Verwey transition—of a factor of 5.9. The results have important applications – quantum computing technologies may rely on spintronics to optimize logistical, […]
Ultrafast charging of batteries using fully new anode material
Nanowerk November 15, 2021 Nanosizing of active electrode material is a common strategy to increase the effective lithium-ion diffusion transport rate, but it also decreases the volumetric energy/power density and stability of the battery. An international team of researchers (the Netherlands, China, Germany) has demonstrated nickel niobate (NiNb2O6) as a new intrinsic high-rate anode material for lithium-ion batteries without the requirement of realizing nano-architectures. The NiNb2O6 host crystal structure exhibits only a single type of channel for lithium-ion intercalation and can be fully lithiated with a capacity of about 244 mAh g−1 at low current densities. A high diffusion coefficient […]
Electron family creates previously unknown state of matter
Science Daily November 5, 2021 What distinguishes a superconducting state from a normal state is a spontaneously broken symmetry corresponding to the long-range coherence of pairs of electrons, leading to zero resistivity and diamagnetism. An international team of researchers (Germany, Sweden, Japan, France) was investigating the superconducting metal Ba1-xKxFe2As2 from the class of iron pnictides when they discovered that four electrons instead of two were forming a bond. It was scrutinized for two years using seven different methods to confirm the result. All data were consistent with the same result. Thus, they concluded that the four-particle electron family in certain […]
These Engineers May Have Come Up With The Perfect Material For Unbreakable Screens
Science Alert November 5, 2021 Lead halide perovskite (LHP) semiconductors show exceptional optoelectronic properties. Barriers for their applications, however, lie in their polymorphism, instability to polar solvents, phase segregation, and susceptibility to the leaching of lead ions. An international team of researchers (Australia, Slovenia, China, UK, France, Japan, Singapore) has developed a process to wrap or bind the nanocrystals in porous glass to stabilize the material, enhance its efficiency, and inhibit the toxic lead ions from leaching out from the materials. The product showed high stability when exposed to heat, light, air, and humidity, and was able to retain 80 […]
Key witness helps scientists detect ‘spooky’ quantum entanglement in solid materials
Phys.org November 8, 2021 The lack of methods to experimentally detect and quantify entanglement in quantum matter impedes our ability to identify materials hosting highly entangled phases, such as quantum spin liquids. An international team of researchers (USA – Oak Ridge National Laboratory, Drew School, Germany, UK, France, Poland) tested three entanglement witnesses using a combination of neutron scattering experiments and computational simulations. Entanglement witnesses are techniques that act as data analysis tools to determine which spins cross the threshold between the classical and quantum realms. To ensure that the witnesses could be trusted, the team applied all three of them […]
Engineers develop flexible, self-healing material to protect steel from the elements
Phys.org October 22, 2021 An international team of researchers (USA – Rice University, South Dakota School of Mines and Technology, SUNY Buffalo, George Washington University, Rensselaer Polytechnic Institute, Canada) has designed a lightweight sulfur–selenium (S–Se) alloy with high stiffness and ductility that can serve as an excellent corrosion-resistant coating with protection efficiency of ≈99.9% for steel in a wide range of diverse environments. S–Se coated mild steel showed a corrosion rate that is 6–7 orders of magnitude lower than bare metal in abiotic (simulated seawater and sodium sulfate solution) and biotic (sulfate-reducing bacterial medium) environments. The coating is strongly adhesive, […]
New chiral nanostructures to extend the material platform
Phys.org October 22, 2021 The majority of previously developed chiral nanomaterials reveal the optical activity in a relatively shorter wavelength range (ultraviolet–visible, UV–vis), not in short-wave infrared (SWIR). An international team of researchers (South Korea, USA – University of Michigan) has demonstrated a versatile method to synthesize chiral copper sulfides using cysteine, as the stabilizer, and transferring the chirality from molecular- to the microscale through self-assembly. The assembled structures showed broad chiroptical activity in the UV–vis-NIR-SWIR region (200–2500 nm). They could tune the chiroptical activity by simply changing the reaction conditions. This approach can be extended to materials platforms for […]
Shape-shifting materials with infinite possibilities
Phys.org October 22, 2021 Researchers at Harvard University have created structural materials, they call totimorphic materials, that have an arbitrary range of shape-morphing capabilities. By having a neutrally stable unit cell they could separate the geometry of the material from its mechanical response at both the individual and solved the problem of balancing the needs of conformability and rigidity. They connected individual unit cells with naturally stable joints, building 2-D and 3-D structures from individual totimorphic cells. Using both mathematical modeling and real-world demonstrations they showed the material’s shape-shifting ability. One single sheet of totimorphic cells could curve up, twist […]
Stronger than spider silk: Bagworm silk enables strong conducting fibers
Science Daily October 22, 2021 Researchers in Japan combined polyaniline, a conducting polymer that can be easily synthesized, with bagworm silk obtained from a bagworm nest. The composite fibers obtained from the silk and polyaniline were 2 microns in diameter and acted as optical waveguides. They demonstrated that green laser light propagates along these fibers, while remaining confined within each fiber. Using SQUID measurements they determined that the fibers can act as paramagnets. By applying the bagworm silk/polyaniline composite in a field-effect transistor device, the research team also confirmed that the composite fiber is suitable for use in textile transistors. […]