[Image above] Credit: NIST
Adapting an old trick used for centuries by both metalsmiths and pastry makers, a team of researchers at MIT has found a way to efficiently create composite materials containing hundreds of layers that are just atoms thick but span the full width of the material. The discovery could open up wide-ranging possibilities for designing new, easy-to-manufacture composites for optical devices, electronic systems, and high-tech materials.
The bacteria that live in dental plaque and contribute to tooth decay often resist traditional antimicrobial treatment, as they can “hide” within a sticky biofilm matrix, a glue-like polymer scaffold. A new strategy conceived by University of Pennsylvania researchers took advantage of the pH-sensitive and enzyme-like properties of iron-containing nanoparticles to catalyze the activity of hydrogen peroxide, a commonly used natural antiseptic.
A team of scientists led by Oak Ridge National Laboratory has developed a novel way to produce 2-D nanosheets by separating bulk materials with nontoxic liquid nitrogen. The environmentally friendly process generates a 20-fold increase in surface area per sheet, which could expand the nanomaterials’ commercial applications.
Graphene oxide has been hailed as a veritable wonder material; when incorporated into nanocellulose foam, the lab-created substance is light, strong and flexible, conducting heat and electricity quickly and efficiently. Now, a team of engineers at Washington University in St. Louis has found a way to use graphene oxide sheets to transform dirty water into drinking water, and it could be a global game-changer.
Detecting noxious gases, such as those released from power plants and other sources, is something that graphene could be even better. Researchers discovered a way to significantly improve its performance by peppering high-quality graphene sheets with boron impurities. Compared to pristine graphene, boron-doped graphene sheets were 27 times more sensitive at detecting nitrogen dioxide and 105 times more sensitive at detecting ammonia.
Storing fluctuating and delivering stable electric power supply are central issues when using energy from solar plants or wind power stations. Scientists from the Leibniz Institute for Interactive Materials (DWI), RWTH Aachen University and Hanyang University in Seoul now significantly improved a key component for the development of new energy storage systems that can accommodate for fluctuations in energy gain.
A new technology developed at Aalto University demonstrates that any picture or text can be inkjet-printed as a solar cell. When light is absorbed in an ordinary ink, it generates heat. A photovoltaic ink, however, coverts part of that energy to electricity. The darker the color, the more electricity is produced, because the human eye is most sensitive to that part of the solar radiation spectrum which has highest energy density.
Researchers at the University of Illinois at Chicago have engineered a potentially game-changing solar cell that cheaply and efficiently converts atmospheric carbon dioxide directly into usable hydrocarbon fuel, using only sunlight for energy.
A new lithium-air battery battery concept, called a nanolithia cathode battery, promises similar theoretical performance as lithium-air batteries while overcoming their drawbacks. In the new variant, the same kind of electrochemical reactions take place between lithium and oxygen during charging and discharging, but they take place without ever letting the oxygen revert to a gaseous form.
While investigating perovskite crystals, University of Groningen scientists made an observation that could make perovskite solar cells more efficient. It could also lead to new sensors for oxygen and water vapor. ‘We assume that there are positively charged groups of traps on the surface because of the crystal structure of the hybrid perovskites’, explains one of the researchers.
A novel, low cost and green lithiated tin vanadium oxide compound has been synthesized via simple, economical and scalable sol-gel method to replace the conventional graphite as electrode material for lithium-ion batteries. This material has a long technological lifespan as it can last long as long as it is well-kept under moisture free condition.
Scientists have identified how to control different properties and stability in hybrid perovskites using lead-free preparation. These new design principles identified super-ion building blocks, clusters of atoms that carry the same charge as the ions that they replace. Scientists can tailor these building blocks improve stability and other desired traits.
Scientists at the National Renewable Energy Laboratory, in collaboration with researchers at Shanghai Jiao Tong University, devised a method to improve perovskite solar cells, making them more efficient and reliable with higher reproducibility. The research involved hybrid halide perovskite solar cells and revealed treating them with a specific solution of methyl ammonium bromide would repair defects, improving efficiency.
Researchers at the University of Illinois at Urbana Champaign have developed a new method for making brighter and more efficient green LEDs. Using an industry-standard semiconductor growth technique, they have created gallium nitride cubic crystals grown on a silicon substrate that are capable of producing powerful green light for advanced solid-state lighting.
Chalcogenide glasses whose optical properties can be modified on a small scale by laser light promises a wide range of applications. Properties of small areas of a versatile optical film can be tweaked by applying ultrashort pulses of laser light, researchers at Agency for Science, Technology and Research (A*STAR), Singapore, show. This tunability makes the material suitable for various light-based applications, from lenses to holograms.
Engineers from the University of Utah and the University of Minnesota have discovered that interfacing two particular oxide-based materials makes them highly conductive, a boon for future electronics that could result in much more power-efficient laptops, electric cars and home appliances that also don’t need cumbersome power supplies.
A team of researchers at Tohoku University has discovered that a Mg-Sc alloy shows shape memory properties. This newly discovered Mg-Sc alloy with a bcc structure shows a martensitic transformation and accordingly, it exhibits superelastic effect at -150ºC. This finding raises the potential for development and application of lightweight SMAs across a number of industries, including the aerospace industry.
The old rules don’t necessarily apply when building electronic components out of 2-D materials, according to scientists at Rice University. The lab analyzed hybrids that put 2-D materials like graphene and boron nitride side by side to see what happens at the border. They found that the electronic characteristics of such “co-planar” hybrids differ from bulkier components.