Science Daily May 6, 2021 Researchers in Japan designed an ion-exchanging method using an A-type zeolite (silicon/aluminum ratio of 1) because of its appropriate pore size for adsorbing CO2. The alkaline-earth ion exchange imparted a large electric field strength that, supposedly, acted as a driving force for the adsorption. They chose a doubly charged calcium ion as the exchange ion since it allowed for the greatest amount of adsorption. To investigate the underlying adsorption mechanism, they carried out far-IR measurements and backed them up with density functional theory calculations. It showed a distinct shift towards longer wavelengths following CO2 adsorption. […]
Tag Archives: S&T Japan
First 3D-printed proton-conductive membrane paves way for tailored energy storage devices
Phys.org April 15, 2021 Researchers in Japan chose mixtures of proton-conducting ionic liquids, inorganic silica nanoparticles, and UV-sensitive photocurable resins as inks for 3D printing of membranes. They found that the mixing ratio of the precursors enabled tuning of the viscosity of inks, and the inks with an appropriate mixing ratio could be applied for 3D printing. They confirmed that the inks can function as proton exchange membranes in all-solid-state electrochemical double-layer capacitors after curing by UV irradiation…read more. TECHNICAL ARTICLE
World’s fastest exfoliation of material has potential use for photoactuator production
Phys.org April 19, 2021 Researchers in Japan found that under irradiation with UV light crystals of a photochromic diarylethene peels off into micrometer sized crystals at a speed of 260 microseconds. These crystals can be potentially applied to macroscopic photomechanical actuators rapidly driven based on molecular machinery. As the material returns to its former molecular structure when exposed to visible light, the exfoliation method positions itself as a candidate for photoactuator manufacturing. A machine made up of photoactuators would not need direct contact with the power source to move. Among its many possible functions, it could be accurately manipulated within […]
Discovery of a mechanism for making superconductors more resistant to magnetic fields
Phys.org March 30, 2021 Researchers in Japan discovered that when the crystalline films of indium is thinned to a two-dimensional atomic layer, the spin, and the momentum of the electrons in the layer are coupled, causing the electron spins to frequently rotate. This offsets the effect of the changes in electronic energy induced by the magnetic field and thus preserves superconductivity. This mechanism can enhance the critical magnetic field up to 16-20 Tesla, which is approximately triple the generally accepted theoretical value. It is expected to have a wide range of applications as it was observed for an ordinary superconducting […]
Toward perdurable flexible electronics
Nanowerk March 23, 20212 In wearable electronics, to acquire stability and simultaneously preserve stretchability, sensitivity, and scalability is of high significance yet challenging for practical device applications. Researchers in Japan developed a kirigami-structured graphene–polymer hybrid nanocomposite for strain sensors by a laser direct writing technique on a polyimide sheet. To protect the device, ecoflex polymer was applied as the passivation layer. Depending on the applications, ecoflex grid-wrapped and film-encapsulated have high stretchability and sensitivity. In demonstrations the sensor platform suffered almost no performance degradation even after >60 000 stretching cycle tests due to less strain within the sensor. As proof-of-concept for […]
Tunable smart materials
Science Daily March 22, 2021 Biological molecules in living organisms have a remarkable ability to form self-assembled structures when triggered by an external molecule. Based on this concept researchers in Japan created a tunable system involving poly(sodium acrylate) microparticles that can have one of two types of chemical groups attached. The adjustable parameters x and y refer to the molar percent of microparticles with β-cyclodextrin and adamantyl residues, respectively. The shape of assemblies formed by microparticles was dependent on the residue content. For assemblies to form, x needed to be at least 22.3. As the value of y increased, the […]
Microwave-assisted recording technology promises high-density hard disk performance
Science Daily March 9, 2021 Researchers in Japan analyzed the operation of the flux-control (FC) device by measuring the temporal resistance change in the sub-nanosecond region. They showed that the reversal of the FC device becomes faster as the bias current is increased and can be completed by 0.5 ns after the transition of the write current. They reproduced the experimental results by micromagnetic simulations using a head model, confirming that the simulations correctly describe the magnetization dynamics of the actual device. The simulations showed that the recording field gain by the FC device appears with little delay after the rise […]
Virtually unlimited solar cell experiments
EurekAlert March1, 2021 Researchers in Japan used machine learning to screen hundreds of thousands of donor: acceptor pairs based on an algorithm trained with data from previously published experimental studies. Trying all possible combinations of 382 donor molecules and 526 acceptor molecules resulted in 200,932 pairs that were virtually tested by predicting their energy conversion efficiency. Basing the construction of our machine learning model on an experimental dataset drastically improved the prediction accuracy. To verify this method, one of the polymers predicted to have high efficiency was synthesized in the lab and tested. Its properties were found to conform with […]
Inductance based on a quantum effect has the potential to miniaturize inductors
Phys.org February 5, 2021 The magnitude of the conventional inductance is proportional to the volume of the inductor’s coil, which hinders the miniaturization of inductors. Researchers in Japan have demonstrated an inductance of quantum-mechanical origin, generated by the emergent electric field induced by current-driven dynamics of spin helices in a magnet. In microscale rectangular magnetic devices with nanoscale spin helices, they observed a typical inductance as large as −400 nanohenry, comparable in magnitude to that of a commercial inductor, but in volume about a million times smaller. The inductance is enhanced by nonlinearity in current and shows non-monotonous frequency dependence, […]
Direct coherent multi-ink printing of fabric supercapacitors
Phys.org January 29, 2021 Fiber-shaped supercapacitors are a desirable high-performance energy storage technology for wearable electronics. The traditional method for device fabrication is based on a multistep approach to construct energy devices, which can present challenges during fabrication, scalability, and durability. An international team of researchers (China, USA – University of Colorado, Carnegie Mellon University, Singapore) has developed an all-in-one coaxial fiber-shaped asymmetric supercapacitor (FASC) device using direct coherent multi-ink writing, 3-D printing technology by designing the internal structure of the coaxial needles and regulating the rheological property and feed rates of the multi-ink. The device delivered a superior areal […]