The exploitation of cathode materials with high capacity as well as high operating voltage is extremely important for the development of aqueous zinc‐ion batteries (ZIBs). Yet, the classical high‐capacity materials (e.g., vanadium‐based materials) provide a low discharge voltage, while organic cathodes with high operating voltage generally suffer from a low capacity. In this work, organic (ethylenediamine)–inorganic (vanadium oxide) hybrid cathodes, that is, EDA‐VO, with a dual energy‐storage mechanism, are designed for ultrahigh‐rate and ultralong‐life ZIBs. The embedded ethylenediamine (EDA) can not only increase the layer spacing of the vanadium oxide, with improved mobility of Zn ions in the V–O layered structure, but also act as a bidentate chelating ligand participating in the storage of Zn ions. This hybrid provides a high specific capacity (382.6 mA h g−1 at 0.5 A g−1), elevated voltage (0.82 V) and excellent long‐term cycle stability (over 10 000 cycles at 5 A g−1). Assistant density functional theory (DFT) calculations indicate the cathode has remarkable electronic conductivity, with an ultralow diffusion barrier of 0.78 eV for an optimal Zn‐ion diffusion path in the EDA‐VO. This interesting idea of building organic–inorganic hybrid cathode materials with a dual energy‐storage mechanism opens a new research direction toward high‐energy secondary batteries.

The electronic structures, charge mobility, and optical properties of the CsXBr3 (X = Ge and Sn) perovskite cells and blue phosphorus (BP) van der Waals heterojunctions have been investigated by using the first-principles method based on density functional theory. We found that the electronic band structures of layered BP and perovskite cells are still retained, a type II band arrangement can be observed in the heterojunctions, and the bandgaps of the heterojunctions gradually decrease with the increase in the number of perovskite layers. Additionally, electrons and holes are gathered at the BP and the perovskite interface of the heterojunctions, respectively. The potential difference formed by net charge aggregation at the BP and perovskite interface can result in a built-in electric field, which promotes the separation of electrons and holes. The maximum carrier mobility of the CsGe(Sn)Br3/BP heterojunctions can reach up to 7.364 × 103 (7.815 × 103) cm2 V−1 s−1 along the y direction of the electron in the CG(S)B/BP heterojunctions by the Boltzmann transport method. Moreover, due to the retention of the high absorption coefficient of monolayer BP, the light absorption spectra of the heterojunctions are obviously increased in the visible and purple light regions, and the absorption coefficient is as high as 105 cm−1, indicating that the heterojunctions could be potentially applied to various optoelectronic devices and solar cells.

The composition and structure of interstellar dust are important and complex for the study of the evolution of stars and the interstellar medium (ISM). However, there is a lack of corresponding experimental data and model theories. By theoretical calculations based on ab-initio method, we have predicted and geometry optimized the structures of Carbon-rich (C-rich) dusts, carbon (12C), iron carbide (FeC), silicon carbide (SiC), even silicon (28Si), iron (56Fe), and investigated the optical absorption coefficients and emission coefficients of these materials in 0D (zero−dimensional), 1D, and 2D nanostructures. Comparing the nebular spectra of the supernovae (SN) with the coefficient of dust, we find that the optical absorption coefficient of the 2D 12C, 28Si, 56Fe, SiC and FeC structure corresponds to the absorption peak displayed in the infrared band (5−8) µm of the spectrum at 7554 days after the SN1987A explosion. And it also corresponds to the spectrum of 535 days after the explosion of SN2018bsz, when the wavelength in the range of (0.2−0.8) and (3−10) µm. Nevertheless, 2D SiC and FeC corresponds to the spectrum of 844 days after the explosion of SN2010jl, when the wavelength is within (0.08−10) µm. Therefore, FeC and SiC may be the second type of dust in SN1987A corresponding to infrared band (5−8) µm of dust and may be in the ejecta of SN2010jl and SN2018bsz. The nano−scale C−rich dust size is ∼ 0.1 nm in SN2018bsz, which is 3 orders of magnitude lower than the value of 0.1 µm. In addition, due to the ionization reaction in the supernova remnant (SNR), we also calculated the Infrared Radiation (IR) spectrum of dust cations. We find that the cation of the 2D layered (SiC)2+ has a higher IR spectrum than those of the cation (SiC)1+ and neutral (SiC)0+.

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Using density functional theory calculation and rigid band model, we investigate the electronic structure and magnetostrictive properties of transition heavy-metal doped Fe-based (Fe–Al, Fe–Si, Fe–B, and Fe–Be) alloys. It is found that a small amount of addition of 4d/5d heavy-metal atoms greatly enhances the coefficient of tetragonal magnetostriction of Fe-based alloys, reaching up to about 1000 ppm in Fe87.5Al6.25Pt6.25 and Fe75Al18.75Rh6.25 alloys. The underlying mechanism is mainly ascribed to combined factors of band narrowing induced by non-bonded states in pure Fe layer, strong spin–orbit coupling effect by heavy metals, and improved mechanical properties, through analysis of the electronic density of states near Fermi level and k-mesh resolved magnetocrystalline anisotropy energy in momentum space. These results provide useful guidance for optimizing the magnetostrictive performance of Fe-based alloys for practical application.

The magnetic flux noise caused by surface spin fluctuations in superconducting quantum interference devices (SQUIDs) limits their development. In this work, we report that different adsorbents such as H, O2, NO, and NO2 that adsorb on the surfaces of Mg-based and Pb-based SQUIDs, respectively, producing large local magnetic moments ranging from 0.7–1.6 μ B, with energy barriers for thermal spin fluctuation as low as 10–30 mK. Moreover, we observe that the presence of H atoms on the surface of MgO can cause the coadsorption of other molecules, which generates additional spin sources. Monte Carlo simulations of the weakly coupled spin on a two-dimensional square lattice produce a low-frequency flux noise spectrum. We suggest eliminating the surface magnetism by coating the surface with monolayer indium phosphide or protecting the surface from other molecules by nonmagnetic preoccupants with a larger adsorption energy. The work provides important physical insights and feasible strategies for reducing magnetic noise sources in superconducting circuits.

Ion implantation is a superior post-synthesis doping technique to tailor the structural properties of materials. Via density functional theory (DFT) calculation and ab-initio molecular dynamics simulations (AIMD) based on stochastic boundary conditions, we systematically investigate the implantation of low energy elements Ga/Ge/As into graphene as well as the electronic, optoelectronic and transport properties. It is found that a single incident Ga, Ge or As atom can substitute a carbon atom of graphene lattice due to the head-on collision as their initial kinetic energies lie in the ranges of 25–26 eV/atom, 22–33 eV/atom and 19–42 eV/atom, respectively. Owing to the different chemical interactions between incident atom and graphene lattice, Ge and As atoms have a wide kinetic energy window for implantation, while Ga is not. Moreover, implantation of Ga/Ge/As into graphene opens up a concentration-dependent bandgap from ~0.1 to ~0.6 eV, enhancing the green and blue light adsorption through optical analysis. Furthermore, the carrier mobility of ion-implanted graphene is lower than pristine graphene; however, it is still almost one order of magnitude higher than silicon semiconductors. These results provide useful guidance for the fabrication of electronic and optoelectronic devices of single-atom-thick two-dimensional materials through the ion implantation technique.