EureakAlert June 13, 2022 Cephalopod (octopuses, squids, and cuttlefish) skin is a soft organ that can endure complex deformations, such as expanding, contracting, bending, and twisting, capable of cognitive sensing and responding that enable the skin to sense light, react and camouflage its wearer. While artificial skins with either these physical or these cognitive capabilities have existed, none has simultaneously exhibited both qualities. An international team of researchers (USA – Pennsylvania State University, University of Houston, South Korea, China) has developed artificial neuromorphic cognitive skins based on arrayed, biaxially stretchable synaptic transistors constructed entirely out of elastomeric materials. Through investigation […]
Tag Archives: Materials science
Room-temperature molecular switch discovery paves the way for faster computers, longer-lasting batteries
Phys.org June 9, 2022 Until now, molecular switching has only been possible when the molecules are extremely cold. Researchers in Australia have developed a semiempirical microscopic model of spin crossover materials (SCO) materials combining crystal field theory with elastic intermolecular interactions. The model reproduces the key experimental results including thermally induced phase transitions, light-induced spin-state trapping (LIESST), and reverse-LIESST. They reproduced and explained the experimentally observed relationship between the critical temperature of the thermal transition. They proposed strategies to design SCO materials with higher TLIESST. The most dramatic increases came from increasing the cooperativity of the spin-state transition by increasing […]
A new arrangement: Using quantum dots to quench the smallest ferrimagnetism
Phys.org May 31, 2022 Researchers in Japan mathematically modeled the electron scattering Kondo effect in ferrimagnetic substances. They used a novel T-shaped lattice of four quantum-dots connected to two reservoirs of electrons to induce a current. While pairs of quantum-dots have been used to model quantum phenomena before, the T-shaped arrangement was new and allowed ferrimagnetism to emerge. Due to the symmetrical geometric configuration of the system, they expected to go from the minimal ferrimagnetic state to the Kondo state without going through other quantum entangled states, amplifying the electrical conductivity as usual. But it was suppressed, contrary to their […]
A new ultra-thin electrode material: A step closer to next-generation semiconductors
Nanowerk May 30, 2022 To overcome the limitations of processing costs, power consumption and integration of miniaturizing silicon-based logic devices, studies are being conducted on electronic and logic devices based on very thin two-dimensional semiconductors at an atomic layer level. An international team of researchers (South Korea, Japan) were able to selectively control the electrical properties of semiconductor electronic devices using Cl-doped tin diselenide (Cl-SnSe2). They were able to freely control the characteristics of the N-type and P-type devices by minimizing defects with the semiconductor interface. In other words, a single device could perform the functions of both N-type and […]
Is it topological? A new materials database has the answer
MIT News May 19, 2022 The recently introduced theories of topological quantum chemistry and symmetry-based indicators (SIs) have facilitated the discovery of topological phases of matter and large-scale searches for materials with experimentally accessible topological properties at the Fermi energy (EF). Away from EF, energetically isolated bands and topological gaps are also useful in numerous experimental settings; they can be accessed via (electro)chemical doping, electrostatic gating, hydrostatic pressure, and nonequilibrium photoexcitation and are relevant to Floquet engineering and nonlinear optical experiments. An international team of researchers (Spain, USA – MIT, Princeton University, Germany) has completed a catalog of stable and […]
Long-hypothesized ‘next generation wonder material’ created
Science Daily May 21, 2022 Scientists have long been interested in the construction of new or novel carbon allotropes. The most well-known carbon allotropes are graphite and diamonds, which are created out of sp2 carbon and sp3 carbon, respectively. However, the traditional methods don’t allow for the different types of carbon to be synthesized together in large capacity. Researchers at the University of Colorado used alkyne metathesis as well as thermodynamics and kinetic control to successfully create a material that could rival the conductivity of graphene but with control. Now the team is looking into the details of it, including […]
Researchers demonstrate organic crystals can serve as energy converters for emerging technologies
Phys.org May 20, 2022 While organic crystals were previously thought to be fragile, an international team of researchers (UAE, USA – New York University) has discovered that some organic crystals are mechanically very robust. They demonstrated that the ferroelectric crystals of guanidinium nitrate exert a linear stroke of 51%, the highest value observed when transitioning at 295–305 K on heating and at 265–275 K on cooling. Their maximum force density is higher than electric cylinders, ceramic piezo actuators, and electrostatic actuators, and their work capacity is close to that of thermal actuators. They demonstrated that the material expanded and contracted over half […]
Unique quantum material could enable ultra-powerful, compact computers
Phys.org May 20, 2022 A long-standing challenge has been to realize materials that integrate and connect tunable electrical transport and tunable spin configurations. Two-dimensional materials offer a platform to realize this concept but known 2D magnetic semiconductors are electrically insulating in their magnetic phase. An international team of researchers (USA – Columbia University, Brookhaven National Laboratory, Oak Ridge National Laboratory, Washington University, Japan) demonstrated tunable electron transport within the magnetic phase of the 2D semiconductor chromium sulfide bromide (CrSBr) and showed strong coupling between its magnetic order and charge transport. Exploiting the sensitivity of magnetoresistance to magnetic order, they uncovered […]
Multisensory hybrid material as smart electronic skin
Nanowerk May 16, 2022 Researchers in Austria proposed a simplified design with biocompatible materials for an efficient electronic skin. They demonstrated that it can deliver multi-stimuli sensitivity with high spatial resolution. While the piezoelectricity of ZnO provided sensitivity to external force, the thermoresponsiveness of the hydrogel core provided sensitivity to surrounding temperature and humidity changes. The hydrogel core exerted mechanical stress onto the ZnO shell, which was translated to a measurable piezoelectric signal. A localized force sensitivity was achieved with very low cross talk. They demonstrated the sensor’s sensitivity to humidity was above and below the hydrogel’s lower critical solution […]
Rigid waterproof coating for paper aims to reduce our dependence on plastic
Science Daily May 13, 2022 Researchers in Japan developed an easy silica–resin coating technique to compensate for paper’s weaknesses, including its lack of water resistance and strength, and proposed its use as an environmentally friendly alternative to plastic. When they dispersed 2 nm anatase TiO2 nanoparticles on the paper’s cellulose fibers it exhibited moderate photocatalytic effects such as methylene blue degradation and antibacterial activity. The porous silica–resin film which has high adsorptive capacity efficiently captured organic pollutants until they decomposed via photocatalytic reactions. As a result, the stable silica–resin–TiO2 composite coating protected paper from the environment for an extended period, […]