Phys.org July 13, 2021 Oxide-based cathode materials are key components of secondary batteries. Problems originating from the lattice oxygen instability in oxide-based intercalation cathodes are widely reported, such as capacity degradation, gas generation, and thermal runaway, highlighting the importance of deep insights into the critical factors for lattice oxygen stability. Researchers in Japan Investigated the lattice oxygen stability in layered rock-salt LiNi1/3Co1/3Mn1/3O2−δ with a focus on oxygen release behavior and relevant changes in crystal and electronic structures. Release of lattice oxygen facilitates cation mixing, transition metal slab expansion, and Li slab contraction, thus deteriorating the layered structure. In the beginning […]
Tag Archives: S&T Japan
Insect-sized robot navigates mazes with the agility of a cheetah
Science Daily July 2, 2021 Researchers in Japan used a curved piezoelectric thin film driven at its structural resonant frequency as the main body of an insect-scale soft robot for its fast translational movements, and two electrostatic footpads were used for its swift rotational motions. These two schemes were simultaneously executed during operations through a simple two-wire connection arrangement. They achieved a high relative centripetal acceleration of 28 body length per square second which is better than those of common insects, including the cockroach. In demonstration the robot passed through a 120-centimeter-long track in a maze within 5.6 seconds. The […]
Stress-free path to stress-free metallic films paves the way for next-gen circuitry
Nanowerk July 4, 2021 To create thin films of tungsten with unprecedentedly low levels of film stress researchers in Japan have been working with scattering (HiPIMS), a sputtering technique. Using argon gas and a tungsten target, the team looked at how ions with different energies arrived at the substrate over time in unprecedented detail. Instead of using a bias pulse set off at the same time as the HiPIMS pulse, they used their knowledge of when different ions arrived and introduced a tiny delay, 60 microseconds, to precisely select for the arrival of high energy metal ions. They found that […]
A bright future: Using visible light to decompose CO2 with high efficiency
Science Daily June 21, 2021 AgIO3 is useful for the CO2 reduction reaction. However, it needs much higher energy than what visible light can provide to function as an efficient photocatalyst. Researchers in Japan developed a new photocatalyst that incorporates single-walled carbon nanotubes (SWCNTs) with AgIO3 and AgI to form a three-component composite catalyst which solve both the synthesis and the electron transfer pathway problems. Spectroscopic observations using the composite showed that during the synthesis process, the encapsulated iodine molecules received charge from the SWCNT and converted into specific ions. They reacted with AgNO3 to form AgI and AgIO3 microcrystals, […]
Scientists use public databases to leap over scourge of publication bias
Eurekalert June 9, 2021 Due to publication bias, there has been little focus on genes other than well-known signature hypoxia-inducible genes. Therefore, researchers in Japan performed a meta-analysis to identify novel hypoxia-inducible genes. They searched publicly available transcriptome databases to obtain hypoxia-related experimental data, retrieved the metadata, and manually curated it, selected the genes that are differentially expressed by hypoxic stimulation, and evaluated their relevance in hypoxia by performing enrichment analyses. They calculated and evaluated the number of reports and similarity coefficients of each gene to HIF1A, which is a representative gene in hypoxia studies. In this data-driven study, they […]
Controlling magnetization by surface acoustic waves
Nanowerk May 27, 2021 Interconversion between electron spin and other forms of angular momentum is useful for spin-based information processing. Well-studied examples of this are the conversion of photon angular momentum and rotation into ferromagnetic moment. Recently, several theoretical studies have suggested that the circular vibration of atoms work as phonon angular momentum; however, conversion between phonon angular momentum and spin-moment has yet to be demonstrated. Researchers in Japan demonstrated that the phonon angular momentum of surface acoustic wave can control the magnetization of a ferromagnetic Ni film by means of the phononic-to-electronic conversion of angular momentum in a Ni/LiNbO3 […]
Creating nanomaterials with new laser driven method
Nanowerk May 31, 2021 For successful implementation of photoelectrocatalytic synthesis of fuels and value-added chemicals hybrid photoelectrodes with low energy consumption and high photocurrent densities are essential. Researchers in Japan have developed a laser-driven technology to print sensitizers with desired morphologies and layer thickness onto different substrates, such as glass, carbon, or carbon nitride (CN). The process uses a thin polymer reactor impregnated with transition metal salts, confining the growth of TMO nanostructures on the interface in milliseconds, while their morphology can be tuned by the laser. Multiple nano-p-n junctions at the interface increase the electron/hole lifetime by efficient charge […]
Weird Electromagnetic Bursts Appear Before Earthquakes – And We May Finally Know Why
Science Alert May 30, 2021 Seismologists have been aware of brief, subtle anomalies in underground electrical fields leading up to an earthquake, sometimes occurring as soon as a few weeks before the quake happens. Research suggests that when gases interact with newly created crack surfaces, the unpaired electrons within the rock crystal defects are thermally stimulated, released into the crack due to the temperature rise at the crack tip via plastic work, and attached to ambient gas molecules to electrify them in a negative state. Researchers in Japan used a customized lab setup to test the reactions of quartz diorite, […]
Using micro-sized cut metal wires, team forges path to new uses for terahertz waves
Phys.org May 14, 2021 Terahertz flat optics is a design concept for replacing conventional three-dimensional bulky optical components with two-dimensional ultra-thin optical components. However, high refractive index materials suitable for flat optics are frequently subject to high Fresnel reflections due to the cumbersome control of the relative permeability it requires. Researchers in Japan fabricated metasurface consisting of 80,036 pairs of cut metal wires on both the front and back of a 5 μm-thick polyimide film with a super-fine ink-jet printer using silver paste ink. They have experimentally shown that the metasurface is reflectionless, has a high refractive index, extremely low […]
Successful synthesis of perovskite visible-light-absorbing semiconductor material
Nanowerk May 7, 2021 Tin-containing oxide semiconductors are cheaper than most semiconductor materials, but their photofunctional applications are constrained by a wide optical band gap. Researchers in Japan doped hydride ions into the tin-containing semiconductor material successfully reducing the band gap from 4 eV to 2 eV, due to the chemical reduction of the tin component that accompanied the hydride ion doping. They verified tin reduction reaction in the semiconductor material through physicochemical measurements. The reduction leads to the generation of a “tin lone electron pair,” whose different electronic states notably contribute to the visible light absorption of the material. […]