Nanowerk October 29, 2022 The lithium-metal batteries cycling encounters a low Coulombic efficiency (CE) due to the unceasing electrolyte decomposition. Improving the stability of solid electrolyte interphase (SEI) suppresses the decomposition and increases CE. However, SEI morphology and chemistry alone cannot account for CE, and a full explanation is still lacking. Researchers in Japan found that in diverse electrolytes, the large shift in the Li electrode potential and its association with the Li+ coordination structure influences the CE. Machine learning regression analysis and vibrational spectroscopy revealed that the formation of ion pairs is essential for upshifting the Li electrode potential, […]
Tag Archives: S&T Japan
Advanced fabric that can cool a wearer down and warm them up
Nanowerk October 11, 2022 Textiles incorporated with phase changing materials (PCMs) can bridge the supply and demand for energy by absorbing and releasing latent heat. The integration of solar heating and the Joule heating function supplies multidriving resources, facilitates energy charging and storage, and expands the service time and application scenarios. Researchers in Japan have developed a fibrous membrane-based textile by designing the hierarchical core–sheath fiber structure for trimode thermal management. Coaxial electrospinning allows an effective encapsulation of PCMs, with high heat enthalpy density enabling the membrane to buffer drastic temperature changes in the clothing microclimate. The favorable photothermal conversion […]
New nanocomposite films boost heat dissipation in thin electronics
Phys.org September 26, 2022 Thermally conductive films with large in-plane anisotropy to prevent thermal interference between heat sources in close proximity and to cool in other directions by diffusion are important for efficient heat dissipation of thin electronic devices. Researchers in Japan have developed flexible composite films composed of a uniaxially aligned carbon-fiber filler within a cellulose nanofiber matrix through liquid-phase three-dimensional patterning. The film exhibited a high in-plane thermal conductivity anisotropy of 433%, with combined properties of a thermal conductivity of 7.8 W/mK in the aligned direction and a thermal conductivity of 1.8 W/mK in the in-plane orthogonal direction. […]
A little strain goes a long way in reducing fuel cell performance
Science Daily September 9, 2022 Using a proton-conducting oxide as an electrolyte film in electrochemical devices introduces an interface, which thermally and chemically generates mechanical strain. To reduce the strain researchers in Japan focused on BZY20, which is a combination of yttrium, barium, zirconium, and oxygen atoms. They found that the atoms on the edges of this cube are 2% closer at the interface between the oxide and the surface than in layers far away from the surface. This compressive strain reduces the proton conductivity to nearly 1/100,000 of what it is in bulk samples. As the layers build up, […]
From bits to p-bits: One step closer to probabilistic computing
Nanowerk August 29, 2022 To engineer probabilistic computers for more advanced computers researchers in Japan have developed a mathematical description to understand what happens to p-bits which could form the basis of probablistic computing. They utilized superparamagnetic tunnel junctions that have high sensitivity to external perturbations and determined the exponents through several independent measurements. They experimentally clarified the ‘switching exponent’ that governs fluctuation under the perturbations caused by magnetic field and spin-transfer torque in magnetic tunnel junctions. This gave them the mathematical foundation to implement magnetic tunnel junctions into the p-bit to sophisticatedly design probabilistic computers. They showed that these […]
Small molecules, giant (surface) potential
Phys.org August 26, 2022 The performance of organic optoelectronic and energy-harvesting devices is largely determined by the molecular orientation and resultant permanent dipole moment, yet this property is difficult to control during film preparation. Researchers in Japan have demonstrated the active control of dipole direction in organic glassy films by physical vapour deposition. It was obtained by utilizing the small surface free energy of a trifluoromethyl unit and intramolecular permanent dipole moment induced by functional groups. According to the researchers their work could pave a way toward the formation of spontaneously polarized organic glassy films, leading to improvement in the […]
Scientists fine-tune ‘tweezers of sound’ for contactless manipulation of objects
Phys.org August 22, 2022 The previous acoustic tweezers developed by researchers in Japan could lift things from reflective surfaces without physical contact, but stability remained an issue. Now, using an adaptive algorithm to fine-tune how the tweezers are controlled, they have drastically improved how stably the particles can be lifted. They found a way of using the same setup to achieve significant enhancements in how they can lift particles from rigid surfaces. With the right arrangement of speakers at the right frequency, amplitude, and phase, it becomes possible to superimpose the sound waves and setup a field of influence which […]
Tiny crystal vases
Nanowerk August 13, 2022 Skeletal or concave polyhedral crystals appear in a variety of synthetic processes and natural environments. However, their morphology, size, and orientation are difficult to control because of their highly kinetic growth character. Researchers in Japan have developed a new method to produce micrometer-scale single crystals in the form of hollow vessels. Upon drop-casting of a heated ethanol solution onto a quartz substrate, the molecules spontaneously assembled into standing vessel-shaped single crystals uniaxially and synchronously over the wide area of the substrate, with small size polydispersity. The crystal edge was active even after consumption of the molecules […]
Record-Breaking Experiment Could Solve a Huge Challenge in Quantum Computing
Science Alert August 8, 2022 Strong interactions between two single atoms have not been harnessed for ultrafast quantum operations due to the stringent requirements on the fluctuation of the atom positions and the necessary excitation strength. Researchers in Japan have developed a technique to trap and cool atoms to the motional quantum ground state of holographic optical tweezers, which allows control of the inter-atomic distance down to 1.5 μm with a quantum-limited precision of 30 nm. Then they used ultrashort laser pulses to excite a pair of these nearby atoms far beyond the Rydberg blockade regime and performed Ramsey interferometry with attosecond […]
At the water’s edge: Self-assembling 2D materials at a liquid-liquid interface
Science Daily July 21, 2022 Researchers in Japan have demonstrated a facile one-pot synthesis of laminated 2D coordination polymer films comprising bis(terpyridine)iron and cobalt at a water/dichloromethane interface. Cross-sectional elemental mapping unveiled the stratum-like structure of the film and revealed that the second layer grows to the dichloromethane side below the first layer. Cyclic voltammetry clarified that the bottom layer mediates charge transfer between the top layer and the substrate in a narrow potential region of mixed-valence states. Furthermore, the bilayer film sandwiched by electrodes in a dry condition shows stable rectification character, and the barrier voltage corresponds to the […]