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Continuous strain engineering of multiferroics not only enhances understanding of their properties but also guides the optimization of their performances for use in electronic, optical, and magnetic devices. However, due to technical challenges in real‐time monitoring of the ferroic orders, the precise evolution process remains unclear. Here, the evolution of the ferroelectric (FE) and antiferromagnetic (AFM) orders are revealed in multiferroic freestanding BiFeO3 films under sequential and anisotropic biaxial strain, using rotational anisotropy second harmonic generation (RA‐SHG) technology and first‐principles calculations. The change and recovery of RA‐SHG patterns illustrate the reversible control of the in‐plane FE polarization in the films by sequential strain application. The in‐plane FE direction can be manipulated within ≈4° by strain along the (100) and (010) directions, while the AFM order is more significantly affected, with ≈8° rotation in RA‐SHG patterns. This research unveils the appearance of new SHG peaks in freestanding BFO films under strain and shows that they evolve independently of FE‐induced SHG linked to lattice changes, suggesting a spin structure‐related variation. This work paves a new way for studying of strain‐manipulated 2D multiferroics and highlights the promise of freestanding perovskite films as low‐dimensional multifunctional devices. This study explores the evolution of ferroelectric (FE) and antiferromagnetic (AFM) orders in freestanding BiFeO3 films under anisotropic strain using rotational anisotropy second harmonic generation (RA‐SHG) and first‐principles calculations. The research reveals reversible control of in‐plane FE polarization and significant AFM order rotation, discovering new SHG peaks linked to spin structure variations. These findings highlight the potential of strain‐engineered perovskite films for low‐dimensional multifunctional devices.

Two-dimensional (2D) materials within the hematene-type binary oxides and perovskites family have recently gathered huge research interest for nanoelectronic devices. However, the exploration of their fascinating topological properties remains limited. Herein, through first-principles calculations, we systematically examine the electronic, magnetic, and topological properties of substitutionally doped 2D ABO 3 (A = As, Sb, or Bi, and B = V, Nb, or Ta) perovskite structures at the B site of a B 2 O 3 system. Interestingly, the atomic substitution makes the 2D ABO 3 structures dynamically stable. Our detailed calculations show the ferromagnetic (FM) and antiferromagnetic phases of these materials. The calculated Chern number ( C ) for the FM 2D ABO 3 (A = As, Sb, or Bi, B = Nb or Ta) suggests their topologically non-trivial phases. Furthermore, the computed nontrivial Berry curvature highlights the topological properties in AsNbO 3 . These findings highlight opportunities in 2D-ABO 3 materials, for applications in spintronics.

Interaction effects can change materials properties in intriguing ways, and they have, in general, a huge impact on electronic spectra. In particular, satellites in photoemission spectra are pure many-body effects, and their study is of increasing interest in both experiment and theory. However, the intrinsic spectral function is only a part of a measured spectrum, and it is notoriously difficult to extract this information, even for simple metals. Our joint experimental and theoretical study of the prototypical simple metal aluminum demonstrates how intrinsic satellite spectra can be extracted from measured data using angular resolution in photoemission. A nondispersing satellite is detected and explained by electron–electron interactions and the thermal motion of the atoms. Additional nondispersing intensity comes from the inelastic scattering of the outgoing photoelectron. The ideal intrinsic spectral function, instead, has satellites that disperse both in energy and in shape. Theory and the information extracted from experiment describe these features with very good agreement.

Development of an electrocatalyst that is cheap and has good properties to replace conventional noble metals is important for H2 applications. In this study, dealloying of an amorphous Ti37Cu60Ru3 alloy was performed to prepare a free‐standing nanostructured hydrogen evolution reaction (HER) catalyst. The effect of dealloying and addition of Ru to TiCu alloys on the microstructure and HER properties under alkaline conditions was investigated. 3 at.% Ru addition in Ti40Cu60 decreases the overpotential to reach a current density of 10 mA cm−2 and Tafel slope of the dealloyed samples to 35 and 34 mV dec−1. The improvement of electrocatalytic properties was attributed to the formation of a nanostructure and the modification of the electronic structure of the catalyst. First‐principles calculations based on density function theory indicate that Ru decreases the Gibbs free energy of water dissociation. This work presents a method to prepare an efficient electrocatalyst via dealloying of amorphous alloys. Dealloying of an amorphous TiCuRu alloy produces a sandwich structure. Cu and Cu2O particles with sizes in the range of 5 to 900 nanometers form on the dealloyed surface, increasing the roughness factor. Ru addition significantly improves the hydrogen evolution reaction performance of the dealloyed TiCu in 1 M KOH electrolyte, even outperforming the commercial Pt/C.

Lithium metal battery is a promising candidate for high‐energy‐density energy storage. Unfortunately, the strongly reducing nature of lithium metal has been an outstanding challenge causing poor stability and low coulombic efficiency in lithium batteries. For decades, there are significant research efforts to stabilize lithium metal anode. However, such efforts are greatly impeded by the lack of knowledge about lithium‐stable materials chemistry. So far, only a few materials are known to be stable against Li metal. To resolve this outstanding challenge, lithium‐stable materials have been uncovered out of chemistry across the periodic table using first‐principles calculations based on large materials database. It is found that most oxides, sulfides, and halides, commonly studied as protection materials, are reduced by lithium metal due to the reduction of metal cations. It is discovered that nitride anion chemistry exhibits unique stability against Li metal, which is either thermodynamically intrinsic or a result of stable passivation. The results here establish essential guidelines for selecting, designing, and discovering materials for lithium metal protection, and propose multiple novel strategies of using nitride materials and high nitrogen doping to form stable solid‐electrolyte‐interphase for lithium metal anode, paving the way for high‐energy rechargeable lithium batteries. Novel stabilization strategies for Li metal anode are proposed by uncovering lithium‐stable materials chemistry across the periodic table using first‐principles calculations. Nitride anion chemistry exhibits unique lithium stability, which is thermodynamically intrinsic or a result of stable passivation. Applying nitride interphase and nitrogen doping provides ultimate stability to protect lithium metal anode.

Chalcogenide glass has a unique volatile transition between high‐ and low‐resistance states under an electric field, a phenomenon termed ovonic threshold switching (OTS). This characteristic is extensively utilized in various electronic memory and computational devices, particularly as selectors for cross‐point memory architectures. Despite its advantages, the material is susceptible to glass relaxation, which can result in substantial drifts in threshold voltage and a decline in off‐current performance over successive operational cycles or long storage time. In this study, we introduce an OTS device made from stoichiometric Sb2Se3 glass, which retains an octahedral local structure within its amorphous matrix. This innovative material exhibits outstanding OTS capabilities, maintaining minimal degradation despite undergoing over 107 operating cycles. Via comprehensive first‐principles calculations, our findings indicate that the mid‐gap states in amorphous Sb2Se3 predominantly stem from the atomic chains characterized by heteropolar Sb‐Se bonds. These bonds exhibit remarkable stability, showing minimal alteration over time, thereby contributing to the overall durability and consistent performance of the material. Our findings not only shed light on the complex physical origins that govern the OTS behavior but also lay the groundwork for creating or optimizing innovative electrical switching materials. The performance degradation upon electrical operations often leads to significant read/write errors in the memory array. In this paper, the authors present a simple selector utilizing stoichiometric Sb2Se3, demonstrating exceptional endurance with minimal drift. The underlying mechanism accountable for its robust performance is elucidated through systematic first‐principles calculations.

Zinc–selenium (Zn–Se) batteries have generated great research interest because they could potentially meet the requirements of a high‐capacity, high energy density storage device. Unfortunately, efforts to control the shuttle effect of polyselenides have yielded limited success. Nanostructured carbon hosts with nonpolar surfaces have insufficient ability to restrict polyselenides within the cathode. Herein, first‐principles calculations are used to successfully study the merits of heteroatom‐doped graphene as an efficient sorbent with an excellent ability to inhibit the shuttle effect of polyselenides. The calculation results show that using B as a dopant could distinctly enhance interaction between hosts and polyselenides, which occur significant charge transfer with polyselenides and reduce the diffusion energy barrier of Zn ions. Then, we synthesized carbon/Se and boron‐doped carbon material/Se composite cathodes proving that B‐doped carbon could restrict the shuttle effect of polyselenides, which increases the electrochemical performance of Zn–Se batteries. Therefore, the theoretical study identifies a delightful restricted material that could potentially restrict the shuttle effect in Zn–Se batteries and provides a foundation and strategy for the fabrication of long‐life, high‐power‐density Zn–Se batteries. According to the first‐principles calculation, B‐doped carbons could occur significant charge exchange with polyselenides and reduce the diffusion energy barrier of Zn ions in zinc–selenium batteries. The test of electrochemical performance demonstrates that B‐doped carbon materials possess a significant restriction effect for the shuttle effect of polyselenides.

Anhydrous phase B (anh‐B) is a dense magnesium silicate with the composition Mg14Si5O24 and space group Pmcb. In magnesium‐rich environments, forsterite reacts with periclase to form anh‐B, and the formation of anh‐B was proposed as a plausible mechanism for the origin of the X‐discontinuity. However, the elastic properties of anh‐B, which are critical for evaluating the seismic features associated with its formation, have not been determined. In this study, we investigated the elasticity of anh‐B at high pressure and temperature via first‐principles calculations. Combining with the elasticity of other minerals, we determined the contrasts caused by the formation of anh‐B: ∼3%, ∼7%, and ∼10% jumps for density, VP, and VS, respectively. The 2%–8% impedance contrasts of the X‐discontinuity can be explained by the formation of 15–60 vol% anh‐B, which requires 3–12 vol% MgO as a reactant. Plain Language Summary The reaction between forsterite and periclase, leading to the formation of anhydrous phase B (anh‐B), has been suggested as a plausible mechanism for the X‐discontinuity. However, the exact impedance contrasts associated with this reaction remain unclear due to the previously undetermined elasticity of anh‐B. To address this knowledge gap, our study utilized first‐principles calculations to thoroughly investigate the elastic properties of anh‐B under mantle conditions. By incorporating the elasticity data of other minerals, we successfully derived the property contrasts resulting from the formation of anh‐B for the first time. Our results indicate that 15–60 vol% anh‐B needs to be formed to explain the X‐discontinuity. These insightful results significantly advance our understanding of the reaction's seismic implications. Key Points We obtained the elasticity of anhydrous phase B under mantle conditions for the first time via first‐principles calculations The formation of anhydrous phase B causes ∼10% P‐wave impedance contrast and ∼13% S‐wave impedance contrast The formation of 15–60 vol% anhydrous phase B can explain the deep X‐discontinuity in the cold subduction zones

Designing catalysts that can simultaneously accelerate reactant activation and hydrogenation remains a central challenge in electrochemical ammonia synthesis. Here, a computation‐guided, dual‐site electrocatalyst design strategy that bridges first‐principles theory with device‐level validation is reported. Guided by density functional theory, Cu‐doped ZnO is identified as an optimal dual‐site platform: Cu sites upshift the Zn d‐band center, strengthening *NO2 adsorption and enabling facile deoxygenation, while ZnO sites promote water dissociation to supply protons at the reaction interface. This cooperative synergy precisely tunes nitrite activation and hydrogenation kinetics, suppressing competing hydrogen evolution. The resulting catalyst achieves a record NH3 yield of 552.16 mg h−1 cm−2 with 87.9% Faradaic efficiency in a membrane electrode assembly—4× and 18× higher than flow‐ and H‐cell configurations, respectively. Operando spectroscopy confirms the predicted mechanism, demonstrating a theory‐to‐device workflow that replaces trial‐and‐error with predictive catalyst design. This approach establishes a generalizable paradigm for developing advanced electrocatalysts for sustainable chemical transformations. Designing Cu doped ZnO catalysts for NO2RR via first principles calculation and boosting electrocatalytic nitrite reduction through Cu‐ZnO synergistic deoxygenation, hydrogenation, and NH3 desorption. Cu doping elevates the d‐band center of Zn, strengthening *NO2 binding and deoxygenation, while ZnO sites regulate water adsorption and dissociation, providing H, establishing a proton‐rich microenvironment, and accelerating interfacial mass transfer kinetics.

2D transition metal borides (MBenes) with abundant surface terminals hold great promise in molecular sensing applications. However, MBenes from etching with fluorine‐containing reagents present inert ‐fluorine groups on the surface, which hinders their sensing capability. Herein, the multilayer fluorine‐free MoBTx MBene (where Tx represents O, OH, and Cl) with hydrophilic structure is prepared by a hydrothermal‐assisted hydrochloric acid etching strategy based on guidance from the first‐principle calculations. Significantly, the fluorine‐free MoBTx‐based humidity sensor is fabricated and demonstrates low resistance and excellent humidity performance, achieving a response of 90% to 98%RH and a high resolution of 1%RH at room temperature. By combining the experimental results with the first‐principles calculations, the interactions between MoBTx and H2O, including the adsorption and intercalation of H2O, are understood first in depth. Finally, the portable humidity early warning system for real‐time monitoring and early warning of infant enuresis and back sweating illustrates its potential for humidity sensing applications. This work not only provides guidance for preparation of fluorine‐free MBenes, but also contributes to advancing their exploration in sensing applications. A simpler and safer hydrothermal‐assisted HCl etching strategy is utilized to successfully prepare multilayer fluorine‐free hydrophilic MoBTx MBene. The multilayer hydrophilic structure with oxygen functional terminals is verified by first‐principles calculations and experimental characterization. It is demonstrated that surface physical adsorption and physical intercalation of water molecules are the main mechanisms of MoBTx‐based humidity sensors.