‘Ubiquitous element strategy’ for overcoming potential deficiencies of rare elements in the synthesis of industrially important electronic, thermionic, and structural materials
Japanese scientists report on a unique ‘ubiquitous element strategy’ for synthesizing industrially important electronic, thermionic, and structural materials using naturally abundant elements. This strategy aims to overcome the ‘rare-element crisis’ that was triggered by increasing demand for such elements as lithium, used in batteries, and dysprosium for Ne-Fe-B permanent magnets.
In the review article published in the journal Science and Technology of Advanced Materials, scientists from Tokyo Institute of Technology describe their research on the synthesis and applications of oxide materials based on the 20–30 most abundant elements including Si, Al, Ca, Na, and Mg. The key to this strategy is an in-depth knowledge of the role of elements in the physical properties of materials—knowledge available from research on the science and technology of nanometer-sized materials.
Research covered in this paper includes:
The conversion of ceramic 12CaO•7Al2O3 (C12A7)—interconnected, positively charged nano-cages—into a chemically and thermally stable transparent conductor which undergoes a metal-superconductor transition at 0.2 K. C12A7 has a wide bandgap of >7 eV and a low work function of 2.4 eV. The authors describe the synthesis, properties, and applications—light-emitting, electron field emitters, and nonvolatile memories—of C12A7 based on their own research.
The generation of ionized oxygen is important in the electronics industry for applications including the production of silicon diode layers on semiconductors. Conventional methods rely on the catalytic action of Pt—a metal in scarce supply. Here, the researchers describe the production of large quantities of atomic oxygen by incandescent heating of 2-mm-diameter tube of yttria-doped zirconia—a solid oxide electrolyte that conducts oxygen ions. This method of generating atomic oxygen is more efficient, highly selective in the types of ions generated, and enables lower temperature oxidation of silicon compared with thermal oxidation.
In another example of the ‘ubiquitous element strategy’ the authors describe the effect of phase transitions on the controlled fracture in mullite ceramics (3Al2O3•2SiO2), which is crucial for impact-resistant armor and bumper shields for spacecraft. The researchers found that mullite exhibited superior protection as Whipple bumper shields compared to conventional aluminum alloys “tested for the impact by an aluminum alloy flyer at 5.5 km/s”.
Other materials discussed include SrTiO3/TiO2, exhibiting a fivefold higher Seebeck effect compared with bulk material; the pulsed laser deposition of flat MgO(111) films on Al2O3(0001) substrates and of atomically flat MgO(111) films on YSZ(111) substrates with NiO(111) buffer layers.
This up to date and highly informative review includes 34 figures and 115 references.Reference
Science and Technology of Advanced Materials 12 (2011) p. 034303. [http://dx.doi.org/10.1088/1468-6996/12/3/034303]Media contacts: Mikiko Tanifuji
Fine felted nanotubes: CAU research team develops new composite material made of carbon nanotubes
22.11.2017 | Christian-Albrechts-Universität zu Kiel
A material with promising properties
22.11.2017 | Universität Konstanz
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
22.11.2017 | Life Sciences
22.11.2017 | Materials Sciences
22.11.2017 | Life Sciences