Science Daily April 30, 2018 Using a novel “flip-chip” technique an international team of researchers (USA – University of Illinois, Japan) prepared single-crystalline Bi2Se3 films with predetermined thicknesses in terms of quintuple layers (QLs) on top of Nb substrates fresh from in situ cleavage. Measurements of the film surface disclosed superconducting gaps and coherence peaks of similar magnitude for both the topological surface states and bulk states and revealed key characteristics relevant to the mechanism of coupling between the topological surface states and the superconducting Nb substrate. This new sample preparation method opens many new avenues in research, building a […]
Category Archives: Advanced materials
Japan Just Found a Huge Rare-Earth Mineral Deposit That Can Supply The World For Centuries
Science Alert April 16, 2018 Rare-earth minerals used in electronic devices are plentiful in layers of the Earth’s crust. There are only a few economically viable areas where they can be mined and they’re generally expensive to extract. Researchers in Japan have found a deposit of rare-earth minerals about 1,150 miles (1,850 km) southeast of Tokyo. It’s within Japan’s exclusive economic zone, so the island nation has the sole rights to the resources there. There’s enough yttrium to meet the global demand for 780 years, dysprosium for 730 years, europium for 620 years, and terbium for 420 years. China has tightly […]
Scientists breed bacteria that make tiny high-energy carbon rings
Science Daily April 6, 2018 Researchers at Caltech used directed evolution to evolve a new function in Escherichia coli bacteria, to produce a high-energy carbon compound, bicyclobutanes, a group of chemicals that contain four carbon atoms arranged so they form two triangles that share a side. The carbon rings are useful starting materials for creating other chemicals and materials… read more. TECHNICAL ARTICLE
New research shows how paper-cutting can make ultra-strong, stretchable electronics
Nanowerk April 3, 2018 A team of researchers in the US (SUNY Buffalo, Temple University) inspired by kirigami used nanoconfinement engineering and strain engineering to create tiny sheets of strong yet bendable electronic materials made of a polymer, PthTFB. The nanosheets can be stretched up to 2000% with simultaneously high electrical conductivity, show remarkable electronic and mechanical reversibility and reproducibility under more than 1000 cycle. The conductivity of the nanosheets increases by three orders of magnitude due to the charge‐transfer complex formation between polymer chain and halogen, while the electrical conductance can be maintained over the entire strain regime. The […]
Thin engineered material perfectly redirects and reflects sound
Science Daily April 10, 2018 Using 3-D printers, an international team of researchers (USA – Duke University, Finland) fabricated a metamaterial made of a series of rows of hollow columns with a narrow opening cut down the middle of one side. The width of the channels between each row of columns and the size of the cavity inside each individual column controls how the sound is manipulated. The program is fed boundary conditions needed to dictate the outgoing and reflected waves’ behavior. They demonstrated redirecting a sound wave coming straight at the metamaterial to a sharp 60-degree outgoing angle with […]
Crash! Scientists explain what happens when nanoparticles collide
Eurekalert April 4, 2018 To understand the forces that control energy transport at the nanoscale, researchers at SUNY Buffalo focused on small nanoparticles — those with diameters of 5 to 15 nanometers. They found that in collisions, particles of this size behave differently depending on their shape. Nanoparticles with crystal facets transfer energy well, making them an ideal component of materials designed to harvest energy; nanoparticles that are rounder in shape, with amorphous surfaces, adhere to nonlinear force laws making them especially useful for shock mitigation; the behavior of nanoparticles with sharp edges varies depending on sharpness of the edges […]
Engineers turn plastic insulator into heat conductor
Science Daily March 30, 2018 Previously engineered ultradrawn nanofibers from a standard sample of polyethylene could only dissipate heat along the length of each polymer chain. A team of researchers in the US (MIT, Argonne National Laboratory) developed a new way to engineer a polymer conductor using oxidative chemical vapor deposition, whereby two vapors are directed into a chamber and onto a substrate, where they interact and form a film creating rigid chains of polymers, rather than the twisted, spaghetti-like strands in normal polymers. 2 square centimeter samples they produced were able to conduct heat at about 2 watts per […]
Knitting electronics with yarn batteries
Science Daily March 28, 2018 Researchers in China twisted carbon nanotube fibers into a yarn, then coated one piece of yarn with zinc to form an anode, and another with magnesium oxide to form a cathode. These two pieces were then twisted like a double helix and coated with a polyacrylamide electrolyte and encased in silicone. In tests the yarn zinc-ion battery was stable, had a high charge capacity, was rechargeable and waterproof. The material could be knitted and stretched, cut into several pieces, each of which could power a watch. In a proof-of-concept demonstration, eight pieces of the cut […]
Microengineered slippery rough surface for water harvesting in air
Nanowerk March 30, 2018 A team of researchers in the US (Pennsylvania State University, UT Dallas) developed a pitcher plant-inspired slippery surface with hydrophilic chemistry. They added the directional grooves and gave the new surface a microscale roughness that increased the surface area. The rate of water and fog harvesting are directly proportional to the amount of surface area on which droplets can form. The rice leaves-inspired grooves whisk the water droplets away through capillary action or gravity. If the slippery rough surface (SRS) material is produced at scale, they estimate that over 120 liters of water can be collected […]
Tuning in to magnetic ink
Eurekalert April 4, 2018 By injecting iron-based reagents into a hot acetic acid solution, researchers in Saudi Arabia synthesized magnetic iron-oxide nanoparticles that dispersed into deionized water to form an ink. When deposited as a thin film on a glass substrate, the new magnetic substrate could act as an energy-storing inductor device with an adjustable capacity of over 20 percent. By modifying the nanoparticles’ surfaces with hydrocarbon chains, they were able to produce free-standing magnetic sheets of a few millimeters in thickness. The discovery boosts prospects for inexpensive electronics that work worldwide by tuning in to multiple cellular bands and […]