Bin Wen

Conversion‐type materials for all‐solid‐state lithium batteries face low conductivity, sluggish kinetics, severe volume expansion, and unstable interfaces. Herein, a MoSe ₂ /C composite is fabricated via a wet‐chemical synthesis approach combined with shell engineering. Density functional theory calculations show that the carbon skeleton enhances conductivity, improves Li ⁺ adsorption, and lowers the diffusion barrier. In situ and finite element analyses confirm that the hollow carbon mitigates volume expansion and redistributes stress. Distribution of relaxation times analysis reveals that stress buffering suppresses interfacial degradation and enhances Li ⁺ migration. Pseudocapacitive analysis shows a slightly higher contribution for pristine MoSe ₂ due to face‐to‐face stacking versus point‐contact packing in MoSe ₂ /C, which sacrifices some initial active area. However, the carbon skeleton accelerates the kinetics of the remaining active regions and provides excellent stress buffering and interfacial stability. Consequently, the MoSe ₂ /C anode exhibits rate capability and long‐term cycling performance in both half‐cells (11 000 cycles at 3 A g ⁻¹ ) and full‐cells (200 cycles at 0.1 C). This work proposes a counterintuitive strategy of “trading part of the initial active area in exchange for superior structural and interfacial stability,” offering a rational design paradigm for conversion‐type materials.

Machine-learning-based nonlocal density functional approximations have demonstrated substantial potential in advancing the applicability of electronic density functional theory. However, most existing approaches rely on handcrafted local or nonlocal descriptors, which limits their scalability in modeling long-range electronic responses. In this work, we propose a novel exchange-correlation functional approximation model-GTAttn-XC, which introduces a learnable attention mechanism to enable unsupervised modeling of long-range electronic responses. By coupling a multiscale real-space grid graph representation with attention operators, the proposed method achieves a unified description of local accuracy and nonlocal interactions, while avoiding the computational overhead associated with explicit high-order correlation terms. Evaluations on multiple benchmark datasets, including MGCDB84, demonstrate that the model consistently delivers high accuracy across a range of tasks, such as weak interactions, reaction energies, barrier heights, and thermochemical energies. These results establish a new technical pathway toward high-accuracy nonlocal exchange-correlation approximations.

The development of high-energy all-solid-state batteries is critically hindered by the electrochemical instability of solid electrolytes against high-voltage oxide positive electrodes. While fluorination is a promising strategy to enhance electrolyte stability, conventional methods are ineffective, resulting in insufficient fluorine content and a debilitating trade-off with ionic conductivity. Here, we report a solid-state anion-exchange strategy that overcomes these limitations by producing core-shell Li-fluoride/LiCl nanocomposite precursors. These precursors enable the synthesis of heavily fluorinated lithium-halide and lithium-sulfide electrolytes that combine high ionic conductivity with good oxidative stability. This stability originates from the formation of a robust, self-limiting LiF-rich interphase at the positive electrode. Consequently, an all-solid-state battery using a Li-rich oxide positive electrode achieves high performance, retaining over 77.5% capacity after 2000 cycles at a high rate of 3 C (1 C = 275 mA/g) and a 5.0 V cutoff. This anion-exchange approach is broadly applicable to other systems and establishes a versatile platform for designing advanced fluorinated materials for next-generation batteries.

Magnesium–zinc (Mg–Zn) alloys derive much of their mechanical strength from the formation and evolution of intermetallic compounds. However, the Mg-rich and intermediate compositional regimes remain insufficiently resolved structurally, hindering a comprehensive and phase-consistent understanding of phase stability and its role in microstructural strengthening. Here, we develop a high-accuracy neuroevolution potential (NEP) for the Mg–Zn system by integrating an active-learning strategy with the CALYPSO structure-search method, enabling systematic exploration of complex configurational phase space with near-first-principles accuracy. Extensive NEP-assisted structure searches reproduce all experimentally established Mg–Zn intermetallic phases and predict a previously unreported thermodynamically stable Mg₃Zn₂ phase with P4₂/mnm symmetry, together with a metastable I4/mcm-Mg₂Zn phase. Mg₃Zn₂ is a plausible candidate constituent phase, as a selected simulated X-ray diffraction feature is consistent with an unassigned peak previously reported in multiphase Mg–Zn alloys. Additionally, Mg₃Zn₂ exhibits superior thermal robustness, retaining higher strength and hardness at elevated temperatures compared with the widely studied MgZn₂. These results demonstrate the effectiveness of NEP-assisted structure prediction in resolving hidden intermetallic phases and establishing systematic structure–property relationships in chemically complex alloy systems.

The Al _8.77 Fe _0.80 Ni _1.20 Si _0.23 (aluminium iron nickel silicate) phase, obtained via high-pressure sintering of an Al-rich prealloy (nominal composition Al _78.08 Fe _8.65 Ni _8.69 Si _4.58 ), is characterized as a novel phase in the Al—Si—Ni—Fe quaternary system. The obtained phase crystallizes in the space group P 2 ₁ / c , with lattice parameters a = 6.2093 (9), b = 6.2579 (9), c = 8.5661 (12) Å, and β = 94.877 (5)°. It is isotypic with Al ₉ Fe _0.7 Ni _1.28 [ a = 6.2406 (1), b = 6.2993 (1), c = 8.5992 (1) Å, and β = 95.129 (1)°; Chumak et al. (2007). Intermetallics , 15 , 1416–1424] and Co ₂ Al ₉ [ a = 6.2163 (3), b = 6.2883 (3), c = 8.5587 (3) Å, and β = 94.772 (4)°; Boström et al. (2005). Z. Anorg. Allg. Chem . 631 , 534–541]. It features a co-occupancy of Al and Si atoms with a ratio of the refined site-occupancy factors of 0.88 (10):0.12 (10), as well a co-occupancy Ni/Fe with site-occupancy factors of 0.60 (4):0.40 (4).

A mixture with the initial chemical composition Al ₅₉ Cr ₂₁ Fe ₁₀ Si ₁₀ was subjected to high-pressure sintering, resulting in the unexpected synthesis of an intermetallic compound with the composition Al _48.18 Cr _22.78 Fe _4.04 Si ₃ , which adopts the Cr _0.88 Fe _0.12 Ga structure type in the space group R 3 m . Structural analysis indicates that Al, Cr and Fe jointly occupy a special position (Wyckoff site 18 h ), with refined site occupancy factors of 0.676 (6), 0.17 (2) and 0.16 (2), respectively. Cr and Fe share another special position (Wyckoff site 3 b ), with refined site occupancy factors of 0.60 (6) and 0.40 (6), respectively. Other atoms in the crystal (Al and Si) fully occupy their sites.

The intermetallic phase (Al _13.28 Si _2.72 )(Fe _1.19 Ni _2.81 ) was obtained by high-pressure sintering (HPS) of a mixture with an elemental atomic ratio corresponding to (Al,Si) ₅ (Fe,Ni). The space group was determined to be C 2/ m with Z = 2. The structure model contains three co-occupied sites with occupancy ratios of Si:Al = 0.679:0.321, Ni:Fe = 0.46:0.54 and Ni:Fe = 0.94:0.06, and five sites with full occupancy of Al atoms.

Magnesium alloys hold significant application value in transportation light weighting, yet the intrinsic strengthening mechanism of their core strengthening phase Mg₁₇Al₁₂ within the high-pressure solidification (HPS) process window remains unclear. Through density functional theory multiscale simulations under 4 GPa, this study reveals the electronic-mechanical coupling mechanism of Mg₁₇Al₁₂, demonstrating that hydrostatic pressure induces lattice contraction to 10.29 Å (Δ = −2.3%) and reduces cohesive energy to −162.49 kJ mol⁻¹, with phonon spectrum confirming high-pressure stability. Material axial stiffness (C₁₁) and shear modulus (C₄₄) increase by 17% and 16%, respectively, achieving a theoretical strength of 9.41 GPa (46% increase) and a 13.7% enhancement in plastic elongation, thereby realizing a synergistic breakthrough in strength and toughness. Electronic structure analysis identifies s–p orbital hybridization of Al bonds triggering a three-dimensional covalent network, while the coexistence of charge localization at Al sites and free electron gas in Mg–Mg bonds establishes a metal-covalent dual-phase ground state, evidenced by reduced Fermi-level density of states and band broadening that reflect dual electron configuration with coexisting localized and itinerant states. Further electronic reconstruction through covalent network strengthening, brittle index optimization (G/B ratio decrease of 8%), and band discretization defines a cross-scale interaction paradigm of ‘quantum orbital modulation → mesoscopic bond reorganization → macroscopic property response’. These findings provide theoretical guidance for HPS parameter design and high-performance magnesium alloy development, advancing lightweight material design toward electronic engineering principles.

The title single-crystal was obtained during the synthesis of a Mg–Al–Zn–Ga alloy, which was achieved by subjecting the alloy to elevated pressures and temperatures. The compound crystallizes in the space group Im 3 (No. 204), with seven distinct metal-atom sites. One of these is occupied by gallium, two by aluminium and zinc, one by zinc and magnesium, and three by magnesium. The structure model contains a vacancy-centred Bergman cluster and a 26-face polyhedron centred on one of the magnesium sites. The crystal structure framework in this study shows a marked similarity to previously examined frameworks, but also evinces significant differences [Edagawa et al. (1992). Philos. Mag. B 65, 1011–1023].