SLAC National Accelerator Laboratory October 19,2018 In tantalum disulfide the charge density waves are all oriented in the same direction in the alpha state. A team of researchers in the US (MIT, SLAC National Accelerator, Harvard University) zapped a thin crystal of tantalum disulfide with a very brief laser pulse. They found that some of the waves flipped into a beta state with a different electron orientation, and the alpha and beta regions were separated by domain walls. A second flash of light dissolved the domain walls and returned the material to its pure alpha state. They could fine-tune the […]
Category Archives: Advanced materials
Self-healing material can build itself from carbon in the air
MIT News October 11, 2018 In proof-of-concept experiments a team of researchers in the US (MIT, UC Riverside) used, a gel matrix composed of a polymer made from aminopropyl methacrylamide and glucose, an enzyme called glucose oxidase, and the chloroplasts (from spinach), that becomes stronger as it incorporates the carbon. It is not yet strong enough to be used as a building material, though it might function as a crack filling or coating material. The results point to a new class of materials capable of using atmospheric CO2 fixation as a regeneration source, finding utility as self‐healing coatings, construction materials, […]
The future of electronic devices: Strong and self-healing ion gels
Phys.org October 12, 2018 Researchers in Japan have created a polymer gel, called the ion gel, by combining two materials, one is repelled by ionic liquids while the other bonds with hydrogen to form a diblock copolymer. The combination of the liquid salts and the diblock copolymer material resulted in a final micellar structure. Hydrogen bonding is reversible and contributes to a material’s ability to self-heal which can be completed within a few hours. The material has applications in flexible electronics…read more. TECHNICAL ARTICLE
New, highly stable catalyst may help turn water into fuel
Science Daily September 28, 2018 Much of the previous work was performed with electrolyzers made from just two elements — one metal and oxygen. A team of researchers in the US (University of Illinois, Argonne National Laboratory) developed a porous material — a pyrochlore oxide of yttrium ruthenate which was more porous and had a new crystalline structure. As a porous structure is highly desirable when it comes electrocatalysts, the new materials could split water molecules at a higher rate than the current industry standard…read more. TECHNICAL ARTICLE
Scientists discover a ‘tunable’ novel quantum state of matter
Nanowerk September 12, 2018 An international team of researchers (China, USA – Boston College, Princeton University, Lawrence Berkeley National Laboratory, Taiwan) arranged atoms on the surface of crystals in many different patterns on ferromagnet to explore the associated phenomena. The electrons hovering above their atoms aligned in a straight line, with two-fold symmetry ignoring the lattice symmetry. When a magnetic field was applied they could turn one line in any direction they chose rotating the line of electrons just by controlling the magnetic field around them. Anisotropy was 100 times more than what theory predicts. The findings open enormous possibilities […]
Multifunctional carbon fibres enable massless energy storage
Physics World September 7, 2018 Carbon fibres’ microstructural designs have been generated to realise a targeted mechanical property. An international team of researchers (Italy, Sweden, France) compared the microstructure and electrochemical performance for two types of commercial carbon fibre, middling mechanical properties and the hardest hitters in terms of structural strength. They found that the intermediate strength carbon fibres were much less organised but still had such high mechanical properties that even smaller crystals might still get good mechanical properties. According to the researchers exploiting the electrochemical properties of carbon fibres could drop device masses by as much as 50%… […]
Cannibalistic materials feed on themselves to grow new nanostructures
Science Daily August 31, 2018 A team of researchers in the US (Oak Ridge National Laboratory, Pennsylvania State University, Drexel University) has shown that by thermal exposure and electron-beam irradiation, hexagonal TiC single adlayers form on defunctionalized surfaces of Ti3C2 MXene at temperatures above 500 °C, generating new 2D materials Ti4C3 and Ti5C4, with the substrate being the source material. The work could lead to the development of bottom-up synthesis methods using substrates terminated with similar hexagonal-metal surfaces, for controllable synthesis of larger-scale and higher quality single-layer transition metal carbides… read more. Open Access TECHNICAL ARTICLE
Dual-layer solar cell sets record for efficiently generating power
Nanowerk August 31, 2018 The combination of hybrid perovskite and Cu(In,Ga)Se2 (CIGS) has the potential for realizing high-efficiency thin-film tandem solar cells because of the complementary tunable bandgaps and excellent photovoltaic properties of these materials. Researchers in Japan used nanoscale interface engineering of the CIGS surface and a heavily doped poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) hole transport layer between the subcells that preserves open-circuit voltage and enhances both the fill factor and short-circuit current. The solar cell achieved a 22.43% efficiency, and unencapsulated devices under ambient conditions maintained 88% of their initial efficiency after 500 hours of aging under continuous 1-sun illumination… read […]
Scientists predict superelastic properties in a group of iron-based superconductors
Science Daily August 30, 2018 By performing pressure simulations within density functional theory for the family of iron-based superconductors an international team of researchers (Germany, USA – Iowa State University) predicts that in these systems the appearance of two consecutive half-collapsed tetragonal transitions at pressures Pc1and Pc2. They identify clear trends of critical pressures and discuss the relevance of the collapsed phases in connection to magnetism and superconductivity. Not only does this study have implications for properties of magnetism and superconductivity, it may have much wider application in room-temperature elasticity… read more. TECHNICAL ARTICLE
Scientists design material that can store energy like an eagle’s grip
Science Daily August 9, 2018 Researchers in the UK have redesigned auxetic materials with smooth curves which distribute the forces and make repeated deformations possible. A major problem for materials exposed to harsh conditions, such as high temperature, is their expansion. The new material can be designed so its expansion properties continuously vary to match a gradient of temperature farther and closer to a heat source. It will be able to adjust itself naturally to repeated and severe changes. The work lays the basis for designs of lightweight 3D supports, which also fold in specific ways and store energy which […]