Phys.org January 13, 2022 For quantum information processing the strongest-performing permanent magnets contain expensive rare-earth metals magnets. Researchers at the Iowa State University scanned vast number of iron-based permanent magnets and established that lanthanum-based hexaferrites show an advantage over conventional samarium-based hexaferrites. They identified LaFe12O19 as an excellent candidate for a gap magnet (iron-based permanent magnet). It is an excellent wide-bandgap semiconductor, can withstand higher voltages, frequencies, and temperatures. They discovered a new quantum state in this material, which strongly locks the magnetization along a fixed direction in the crystal, it could host other rare earths possessing nontrivial localized electronic […]
Tag Archives: Advanced materials
New nanocrystals put a tiny twist on useful materials
Phys.org January 12, 2022 Conductive MOFs possess rich compositions with complex architectures, but remain unexplored as nanocrystals, hindering their incorporation into scalable devices. MOFs form via a series of chemical reactions that join metal ions with linker molecules. Researchers at the University of Oregon made iron triazolate nanoparticles by adding a third ingredient, molecules that mimic the linkers, but that can only bind to something on one end. They act like dead-ends for the growing MOF, ensuring it stays small. They behaved differently at different sizes and temperatures. They could tune the materials to behave a certain way, by adjusting […]
Changing the properties of ferroelectric materials by vacating a single oxygen atom
Phys.org January 3, 2022 In ferroelectric materials, a slight shift of the atoms causes significant changes in the electric field and in the contraction or expansion of the material. An international team of researchers (Israel, USA – UCLA) succeeded in deciphering the atomic structure and electric field deployment in domain walls at the atomic scale. They corroborate the assumption that domain walls allow for the existence of a two-dimensional border between domains as a result of partial oxygen vacancy in areas that are common to two domains, thus enabling greater flexibility in the deployment of the local electric field. They […]
Scientists find ways to help perovskite solar cell ‘self-healing’
Nanowerk December 28, 2021 Organic-inorganic hybrid perovskite solar cells, considered as a competitive alternative to conventional silicon solar cells, are prone to degrade when exposed to air. An international team of researchers (China, Greece, Australia) introduced PVP to the methylammonium lead iodide perovskite precursor. It can control crystal growth and endow the devices with self-healing ability in a moisture environment. When it was introduced in perovskite solar cells, it acted as a protective armor with an automatic blood backflow effect against water vapor. In addition, PVP can improve crystal growth with fewer defects and larger grains…read more. TECHNICAL ARTICLE
Magnetic ‘hedgehogs’ could store big data in a small space
Nanowerk December 17, 2021 An international team of researchers (USA- Ohio State University, Mexico) used a magnetic microscope to visualize the patterns formed in thin films of manganese germanide. The magnetism in this material follows helices, like the structure of DNA which leads to numerous patterns. The images revealed that in certain parts of the sample, the magnetism at the surface was twisted into a pattern resembling the spikes of a hedgehog, about 50 nanometers in size. The hedgehog patterns could be shifted on the surface with electric currents or inverted with magnetic fields. This foreshadows the reading and writing […]
Study shows that zwitterions can raise the dielectric constant of soft materials
Phys.org December 17, 2021 To create efficient energy storage solutions and actuators, engineers need materials with high dielectric constant. The current method of incorporating polar additives with a high dielectric constant has not yielded high enough dielectric constant for many applications. Researchers at Penn State University have demonstrated a new method for raising the dielectric constant by adding zwitterions, small molecules with one positive electrical charge and one negative electrical charge separated by covalent bonds. Zwitterions are non-volatile molecules that are highly polar. In their recent experiments, the team added the zwitterions to polymeric single-ion conductors. Zwitterions raised dielectric constant […]
Innovative textile vents to release heat when you sweat
Phys.org December 15, 20212 Researchers at Duke University have developed and demonstrated a multimodal adaptive wearable with moisture-responsive flaps composed of a nylon/metal heterostructure, which can simultaneously regulate convection, sweat evaporation, and mid-infrared emission to accomplish large and rapid heat transfer tuning in response to human perspiration vapor. They showed that the metal layer not only plays a crucial role in low-emissivity radiative heating but also enhances the bimorph actuation performance. The multimodal adaptive mechanism expands the thermal comfort zone by 30.7 and 20.7% more than traditional static textiles and single-modal adaptive wearables without any electricity and energy input, making […]
N-type conductive tin sulfide thin films: Towards environmentally friendly solar cells
Science Daily December 13, 2021 An international team of researchers (Japan, USA – National Renewable Energy Laboratory) has fabricated n-type conductive SnS thin films by impurity doping. Conventional SnS thin films are usually p-type conductive. Thus, SnS thin-film solar cells have been fabricated using a pn heterojunction with p-type SnS thin film and other n-type semiconductor thin films, such as CdS. However, the conversion efficiency of such heterojunction devices is approximately 5%. The SnS thin-film solar cells employing a pn homojunction, which uses SnS thin films for both p-type and n-type layers, is expected to exhibit higher conversion efficiency. Utilizing […]
New copper surface eliminates bacteria in just two minutes
Phys.org December 13, 2021 The ions released from the metal’s surface are toxic to bacterial cells. But this process is slow when standard copper is used. Researchers in Australia used a special copper mold casting process to make the alloy, arranging copper and manganese atoms into specific formations. The manganese atoms were then removed from the alloy using dealloying leaving pure copper full of tiny microscale and nanoscale cavities in its surface. The resulting copper is composed of comb-like microscale cavities and within each tooth of the comb structure are much smaller nanoscale cavities; it has a massive active surface […]
Unbreakable bionic glove made from silk for human-machine-interfacing
Nanowerk December 14, 2021 An international team of researchers (Denmark, Finland) has designed a new electronic material called CareGum by mixing silk fibroin and reduced graphene oxide. They used a phenolic glue to facilitate sacrificial and hierarchical hydrogen bonds. The hierarchal bonding scheme gives rise to high mechanical toughness, record-breaking elongation capacity of ≈25 000%, excellent conformability to arbitrary and complex surfaces, 3D printability, a tenfold increase in electrical conductivity, and a fourfold increase in Young’s modulus compared to its pristine counterpart. Since its conductivity is based on ions, CareGum can convey information over longer distances than rigid electronics based […]