Phys.org July 26, 2018 A team of researchers in the US (University of Colorado, Boulder, NIST) designed two new polymers, one which starts as a solid and can be converted into liquid, and the other which starts as a liquid and can be converted into a solid. The solid and liquid polymers both switch phase when irradiated by UV light with a 365-nm wavelength for about five minutes. However, the light affects the two materials differently. Using light instead of temperature or pressure to control the phase changes makes it possible to exert exquisite spatial control over these phase changes, […]
Category Archives: Advanced materials
Superflexible aerogels are highly efficient absorbents, thermal insulators, and pressure sensors
Phys.org July 26, 2018 Researchers in Japan have introduced extremely elastic aerogels that are easy to process and can be produced at low cost. Their success relies on a doubly cross-linked organic-inorganic network structure with adjustable network density. The delicate structures are highly elastic. They can be bent, rolled, twisted, and cut into desired shapes. The more densely crosslinked versions exhibit high thermal insulation, surpassing conventional materials like polyurethane foam. When exposed to a mixture of hexane and water, they exclusively absorb the hexane, which can subsequently be removed by squeezing the material like a sponge or by evaporation. This […]
Scientists develop new materials that move in response to light
Phys.org July 24, 2018 A team of researchers in the US (Tufts University, Los Alamos National Laboratory) has developed magnetic elastomeric composites that move in different ways when exposed to light. The flexible material composites, when illuminated, are capable of macroscale motion, through the interplay of optically absorptive elements and low Curie temperature magnetic materials. These composites can be formed into films, sponges, monoliths, and hydrogels, and can be actuated with light at desired locations. They demonstrated the versatility of the material for gripping and releasing, heliotactic motion, light-driven propulsion, and rotation… read more. TECHNICAL ARTICLE
Nanocrystal links could lead to better electronics
Nanowerk July 17, 2018 Colloidal nanocrystals can be easily tweaked to have a number of different properties as a function of their size. Depending on how they’re built, colloidal nanocrystals could be made into solar panels, electronics or optical devices. Through an integrated theoretical and experimental approach to characterize the transport properties of colloidal nanocrystals, an international team of researchers (Germany, USA – University of Chicago, Argonne National Laboratory) found that the inorganic links between the nanoparticles themselves are changing and reforming on the surface of the nanoparticles. The linker molecules react where they are attached and form a sort […]
New coatings make natural fabrics waterproof
Science Daily June 29, 2018 Conventional water-repellent coatings have been shown to persist in the environment and accumulate in our bodies. Researchers at MIT have developed a process that allows for iCVD deposition of durable, conformal short fluorinated polymers stabilized with a crosslinking agent resulting in high hydrophobicity, low liquid adhesion while maintaining initial substrate breathability. To further enhance the dynamic water repellency performance, the chemical treatment is combined with physical texturing making this combined approach a suitable candidate to meet the industrial needs. The process works on different kinds of materials including cotton, nylon, linen and paper, opening a […]
On track to commercial extraction of uranium from seawater
Next Big Future June 16, 2018 Seawater contains about three parts per billion of uranium. It’s estimated that there is at least four billion tons of uranium in seawater, which is about 500 times the amount of uranium known to exist in land-based ores which must be mined. A team of researchers in the US (PNNL, industry) has chemically modified regular, inexpensive acrylic fiber to convert it into an adsorbent which is selective for uranium, efficient and reusable. The material is inexpensive, adsorbent properties are reversible, and the captured uranium is easily released to be processed into yellowcake. Analysis of […]
Scientists predict a new superhard material with unique properties
Phys.org June 14, 2018 An international team of researchers (Russia, Armenia, China) predicted new tungsten borides, some of which are promising hard materials that are expected to be stable in a wide range of conditions, according to the computed composition–temperature phase diagram. The new boron-rich compound WB5 is predicted to be superhard, with a Vickers hardness of 45 GPa, possess high fracture toughness of ∼4 MPa·m0.5, and thermodynamically stable in a wide range of temperatures at ambient pressure, and remains a high-performance material even at very high temperatures. Superhard substances have a broad scope of application in well drilling, machine […]
In desert trials, next-generation water harvester delivers fresh water from air (w/video)
Eurekalert June 8, 2018 In 2017, researchers at UC Berkeley successfully field tested their newest prototype water harvester in the Arizona desert. It worked as designed, sucking water out of the air without any power other than sunlight. They demonstrated that the harvester should be easy to scale up by simply adding more of the water absorber, a highly porous MOF. A team of researchers in the US (UC Berkeley, Lawrence Berkeley National Laboratory) has created a new MOF based on aluminum, called MOF-303, that is at least 150 times cheaper and captures twice as much water in lab tests. This […]
Evidence for a new property of quantum matter revealed
Science Daily June 12, 2018 Quantum spin liquids do not achieve an ordered magnetic state, even at the lowest temperatures. An international team of researchers (USA – Johns Hopkins University, Georgia Institute of Technology, NSF, Argonne National Laboratory, Russia) studied an organic compound called k-(BEDT-TTF)2Hg(SCN)2 Br that may be both a spin liquid and a dipole liquid. They observed that in this quantum material even at super-cold temperatures, electrical dipoles are still present and fluctuate according to the laws of quantum mechanics. The discovery has potential application in quantum computing and information storage… read more. TECHNICAL ARTICLE
MOF material offers selective, reversible and repeatable capture of toxic atmospheric gas
Science Daily June 11, 2018 An international team of researchers (UK, USA – Oak Ridge National Laboratory, Russia, France, China) has developed an MOF, denoted as MFM-300(Al), which exhibits reversible, selective capture of nitrogen dioxide at ambient pressures and temperatures — at low concentrations — in the presence of moisture, sulfur dioxide and carbon dioxide. Despite the highly reactive nature of nitrogen dioxide, the MFM-300(Al) material proved extremely robust, demonstrating the capability to be fully regenerated, or degassed, multiple times without loss of crystallinity or porosity. This work may pave the way for the development of future capture and conversion technologies… […]