Scientists experimentally realize 2D Si-Ge alloys with tunable electronic properties, getting us closer to a breakthrough in modern electronics. Semiconducting 2D alloys could be key to overcoming the technical limitations of modern electronics. Although 2D Si-Ge alloys would have interesting properties for this purpose, they were only predicted theoretically. Now, scientists from Japan Advanced Institute of Science and Technology have realized the first experimental demonstration. They have also shown that the Si to Ge ratio can be adjusted to fine…
Carbon dioxide (CO2) is one of the major greenhouse gases causing global warming. If carbon dioxide could be converted into energy, it would be killing two birds with one stone in addressing the environmental issues. A joint research team led by City University of Hong Kong (CityU) has developed a new photocatalyst which can produce methane fuel (CH4) selectively and effectively from carbon dioxide using sunlight. According to their research, the quantity of methane produced was almost doubled in the…
Just as pressing a guitar string produces a higher pitch, sending laser light through a material can shift it to higher energies and higher frequencies. Scientists have discovered how to use this process to explore quantum materials in more detail. Topological insulators are one of the most puzzling quantum materials – a class of materials whose electrons cooperate in surprising ways to produce unexpected properties. The edges of a TI are electron superhighways where electrons flow with no loss, ignoring…
Scientists at Tokyo Institute of Technology (Tokyo Tech) produced and extensively characterized novel organic molecules with a long helical structure. Unlike previous helical molecules, these longer compounds exhibit special interactions between coils that could give rise to interesting optical and chemical properties with applications in light polarization, catalysis, and molecular springs. More often than not, organic molecules with unique 3D structures bear physicochemical properties that cannot be found in other types of compounds. Helicenes, chains of simple benzene rings that…
Rice, Los Alamos make low-cost, scalable photocathodes from halide perovskites Rice University engineers have discovered technology that could slash the cost of semiconductor electron sources, key components in devices ranging from night-vision goggles and low-light cameras to electron microscopes and particle accelerators. In an open-access Nature Communications paper, Rice researchers and collaborators at Los Alamos National Laboratory (LANL) describe the first process for making electron sources from halide perovskite thin films that efficiently convert light into free electrons. Manufacturers spend…
Beauty in imperfection Scientists clarify how crystal defects in Ni-based alloys give rise to high thermoelectric conversion efficiencies, advancing thermoelectric technology. If we are to prevent the impending environmental crisis, it is imperative that we find efficient and sustainable ways to avoid being wasteful. One area with much room for improvement is the recycling of waste heat from industrial processes and technological devices into electricity. Thermoelectric materials are at the core of research in this field because they allow for…
Materials scientists of Far Eastern Federal University (FEFU), in collaboration with an international research team, have advanced the design of composite ceramic materials (Ce3+:YAG-Al2O3), i.e. solid-state light converters (phosphors) that can be applied in-ground and aerospace technologies. The LED systems based on the developed materials to save 20-30 percent more energy compared to commercial analogues. A related article was published in Materials Characterization. Over 15% of the total global electricity production or about $ 450 billion annually spent on lighting….
XSEDE Stampede2 simulates polarized elongation of actin filaments Our cells are filled with ‘bones,’ in a sense. Thin, flexible protein strands called actin filaments help support and move around the bulk of the cells of eukaryotes, which includes all plants and animals. Always on the go, actin filaments constantly grow, shrink, bind with other things, and branch off when cells move. Supercomputer simulations have helped solve the mystery of how actin filaments polymerize, or chain together. This fundamental research could…
Metallurgists have all kinds of ways to make a chunk of metal harder. They can bend it, twist it, run it between two rollers or pound it with a hammer. These methods work by breaking up the metal’s grain structure — the microscopic crystalline domains that form a bulk piece of metal. Smaller grains make for harder metals. Now, a group of Brown University researchers has found a way to customize metallic grain structures from the bottom up. In a…
Fraunhofer LBF identifies potential for lightweight design Increasingly stringent statutory emission limits are pushing the automotive industry toward innovative lightweight design solutions. In this context, the fatigue strength of thin sheet metal structures, especially made from multi-material, is becoming increasingly important. The car manufacturer Opel Automobile GmbH, together with Fraunhofer LBF and SAM of TU Darmstadt, has developed innovative numerical fatigue strength assessment approaches for multi-material joints based on fatigue tests of hybrid joined shear and peel specimens. The method…
A promising lead halide perovskite is great at converting sunlight to electricity, but it breaks down at room temperature; now scientists have discovered how to stabilize it with pressure from a diamond anvil cell. Among the materials known as perovskites, one of the most exciting is a material that can convert sunlight to electricity as efficiently as today’s commercial silicon solar cells and has the potential for being much cheaper and easier to manufacture. There’s just one problem: Of the…
Rice model may lead to better materials for aerospace, automotive, medical applications. Carbon nanotube fibers are not nearly as strong as the nanotubes they contain, but Rice University researchers are working to close the gap. A computational model by materials theorist Boris Yakobson and his team at Rice’s Brown School of Engineering establishes a universal scaling relationship between nanotube length and friction between them in a bundle, parameters that can be used to fine-tune fiber properties for strength. The model…
Scientists at the U.S. Department of Energy’s Ames Laboratory and collaborators at Brookhaven National Laboratory and the University of Alabama at Birmingham have discovered a new light-induced switch that twists the crystal lattice of the material, switching on a giant electron current that appears to be nearly dissipationless. The discovery was made in a category of topological materials that holds great promise for spintronics, topological effect transistors, and quantum computing. Weyl and Dirac semimetals can host exotic, nearly dissipationless, electron…
Computer simulations hold tremendous promise to accelerate the molecular engineering of green energy technologies, such as new systems for electrical energy storage and solar energy usage, as well as carbon dioxide capture from the environment. However, the predictive power of these simulations depends on having a means to confirm that they do indeed describe the real world. Such confirmation is no simple task. Many assumptions enter the setup of these simulations. As a result, the simulations must be carefully checked…
Researchers at the Institute of Natural Products Engineering at TU Dresden have developed an insulating material made from recycled paper for shipping temperature-sensitive foods and medicines. As part of a research and development project, the fundamentals were laid for the production of ecologically sustainable fresh food shipping packaging and thus for an alternative to environmentally harmful Styrofoam and plastic packaging. Thermally insulated packaging keeps shipping goods within a certain temperature range. The packaging provides passive cooling, often with additional coolants,…
Like a person breaking up a cat fight, the role of catalysts in a chemical reaction is to hurry up the process – and come out of it intact. And, just as not every house in a neighborhood has someone willing to intervene in such a battle, not every part of a catalyst participates in the reaction. But what if one could convince the unengaged parts of a catalyst to get involved? Chemical reactions could occur faster or more efficiently….