Abstract 1. Scalable-manufactured randomized glass-polymerhybridmetamaterialfordayti...
1. Random glass-polymer hybrid metamaterial
(Scalable-manufacturedrandomized glass-polymer hybrid metamaterial for daytime radiative cooling)
Passive radiant cooling is the absorption of heat from the surface and its radiation into the space, ie infrared radiation into the transparent atmosphere. However, the energy density mismatch between solar radiation and low infrared radiation flux from near ambient temperature surfaces requires materials that are capable of strongly emitting thermal energy and hardly absorbing sunlight. Zhai et al. randomly embed resonant polar dielectric microspheres into a polymer matrix to produce a metamaterial that is completely transparent to the solar spectrum and has an infrared emissivity greater than 0.93 in the atmospheric window. When the backing is silver coated, the metamaterial shows a radiation cooling power of 93 W/m2 in direct sunlight. More critically, Zhai et al. demonstrated a high-throughput, and economical, roll-to-roll manufacturing approach that is critical to promoting radiant cooling of energy technologies. (Science DOI: 10.1126/science.aai7899)
2. Bloch-Siegert movement in single layer WS2
(Large, valley-exclusive Bloch-Siegert shift in monolayer WS2)
Coherence effects with non-resonant light can be used to shift the energy levels of atoms, molecules, and solids. The main effect is the optical Stark movement, but there are also additional contributions from the so-called Bloch-Siegert movement, making it difficult to directly and uniquely observe in solids. Sie et al. observed a very large Bloch-Siegert movement in a single layer of tungsten disulfide (WS2) under infrared optical driving. Since the two effects obey the opposite selection rules at different valleys, by controlling the light helicity, the Bloch-Siegert movement can be restricted to one valley and the optical Stark movement occurs at the other valley. This large valley-unique Bloch-Siegert movement enhances the control of the valley properties of two-dimensional materials. (Science DOI: 10.1126/science.aal2241)
3. "Ab initio" synthesis of zeolites used to pre-establish catalytic reactions
("Ab initio" synthesis of zeolites for preestablished catalyticreactions)
Unlike homogeneous catalysts that are typically designed for specific reactions, zeolites are heuristically studied and optimized heterogeneous catalysts. Gallego et al. proposed a method for synthesizing active and selective zeolites by simulating a pre-established reaction state transition (TS) to be catalyzed using an organic structure directing agent. In these zeolites, pores and cavities close to the molecular recognition mode can be produced. For disproportionation of toluene and isomerization of ethylbenzene to xylene, TS is greater than the reaction product. Zeolite ITQ-27 showed high disproportionation activity and ITQ-64 showed high selectivity for the desired para and ortho isomers. For the case of products of similar size and TS, Gallego et al. synthesized a catalyst MIT-1 for isomerization of internal dicyclopentane to adamantane. (Science DOI: 10.1126/science.aal0121)
4. Atomic-scale sensing of a single-atom magnetic dipole field
(Atomic-scalesensing of the magnetic dipolar field from single atoms)
Spin resonance provides the high energy resolution required to determine the structure of organisms and materials by sensing weak magnetic interactions. In recent years, significant achievements have been made in the detection and coherent control of atomic scale spin centers for sensitive local magnetometers. However, localizing spin sensors with sub-nanometer precision and characterizing spin-spin interactions remains an important challenge. Choi et al. used a single Fe atom as an electron spin resonance (ESR) sensor in a scanning tunneling microscope to measure the magnetic field emitted by nearby spins with atomic accuracy. Choi et al. measured the interaction energy between the ESR sensor and the adsorbed atoms by magnetically (Fe and Co) components artificially constructed on the surface of the magnesium oxide, which showed an inverse cubic distance dependence (r-3.01 ± 0.04). This indicates that the atoms are primarily coupled by magnetic dipole-dipole interactions, which, depending on the observation, dominate the atomic spacing greater than 1 nm. This dipole sensor can determine the magnetic moment of a single adsorber with high precision. Achieving atomic-scale spatial resolution in spin remote sensing can ultimately result in structural imaging of individual magnetic molecules, nanostructures, and spin-labeled biomolecules. (Nature Nanotechnology DOI: 10.1038/NNANO.2017.18)
5. Volume rectification effect in polar semiconductors
(Bulkrectification effect in a polar semiconductor)
The non-centrosymmetric conductor is a very interesting material platform with rich spintronic functions and unique superconducting properties, usually produced in polar systems with Rashba-type spin-orbit interactions. Polar conductors should also have inherent non-reciprocal transmissions in which the currents to the right and left are different from each other. However, such rectification is difficult to achieve in bulk materials because, unlike translationally asymmetric pn junctions, the bulk material is translationally symmetric, which makes this phenomenon very rare. Ideue et al. reported the bulk rectification effect in the three-dimensional Rashba-type polar semiconductor BiTeBr. The experimentally observed non-reciprocal electrical signals were quantitatively interpreted by considering the theoretical calculation of the Boltzmann equation for the giant Rashba spin-orbit coupling. This result provides a microscopic understanding of the inherent rectification effects inherent to polar conductors and a simple electrical model for estimating spin-orbit parameters in various non-centrosymmetric systems. (Nature Physics DOI: 10.1038/NPHYS4056)
6. Remote steric effect enhancement nickel catalysis
(Parameterization of phosphine ligands demonstrates enhancement of nickel catalysis via remotesteric effects)
Because Ni has low cost, abundant earth stock and its ability to promote cross-coupling reactions, it has recently developed rapidly in the field of Ni-catalyzed cross-coupling. Although ligand design has driven advances in the field of Pd-catalyzed cross-coupling, researchers are still paying little attention to the development of specific Ni ligands. Wu et al. have discovered a class of phosphines that can catalyze Csp3 Suzuki coupling with acetal Ni to produce benzyl ether. This benzyl ether-producing reaction utilizes previously known Ni ligands and Pd designer phosphines. It is difficult to achieve. Using parameters to quantify the spatial and electronic properties of phosphine in combination with regression statistical analysis, Wu et al. identified a ligand model. The study shows that effective phosphine compounds have long-term steric hindrance, a concept that can guide future design of ligands with Ni. The analysis reveals that the ligand space environment, that is, the two classical descriptors of the cone angle and the % buried volume are not equivalent. (NatureChemistry DOI: 10.1038/NCHEM.2741)
7. Revitalizing lithium metal anodes for high-energy batteries
(Reviving thelithium metal anode for high-energy batteries)
Lithium-ion batteries have had a profound impact on our daily lives, but the inherent limitations make it difficult for lithium-ion chemistries to meet the growing demand for portable electronics, electric vehicles and grid-scale energy storage. Therefore, chemicals other than Li ions are currently being studied and need to be made available for commercial applications. The use of metallic Li is one of the most popular choices for next-generation Li batteries, especially for Li-S and Li-air systems. After decades of being forgotten for safety issues, metallic lithium is now ready for revival thanks to the development of analytical tools and nanotechnology-based solutions. In this review, Lin et al. first summarize the current understanding of lithium anodes, then highlight the recent key advances in material design and advanced characterization techniques, and finally discuss the opportunities and possibilities for Li anodes to be developed in future applications. The direction. (Nature Nanotechnology DOI: 10.1038/NNANO.2017.16)
8. Advanced Characterization Technology for Lithium Ion Batteries
(State-of-the-art characterization techniques for advanced lithium-ionbatteries)
In order to meet the needs of the future industry from personal devices to automobiles, it is also necessary to improve durability and reduce costs in order to achieve the most advanced rechargeable lithium-ion batteries. Understanding electrode degradation mechanisms is critical to enhancing battery performance and longevity. Various advanced in-situ and real-time analytical characterization tools developed over the past few years are indispensable for optimizing battery materials, understanding battery degradation mechanisms, and ultimately improving overall battery performance. Lu et al. reviewed recent advances in the development and application of advanced characterization techniques, such as in-situ transmission electron microscopy of high performance lithium-ion batteries. Using three representative electrode systems, layered metal oxides, lithium-rich layered oxides, and Si- or Sn-based alloys, discusses how these tools can help researchers understand battery processes and design better battery systems. . They also summarized the application of characterization techniques to lithium-sulfur and lithium-air batteries and highlighted the importance of these technologies in the development of next-generation batteries. (Nature Energy DOI: 10.1038/nenergy.2017.11)
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