ABSTRACT Sodium‐ion batteries (SIBs) are widely regarded as a promising alternative to lithium‐ion batteries due to their abundant sodium resources, broad geographical distribution, and low cost, rendering them particularly attractive for large‐scale energy storage applications. However, the development of anode materials that simultaneously deliver high energy density, long cycle life, and robust safety remains a critical challenge for the commercialization of SIBs. Currently, SIB anode materials can be generally classified into intercalation‐type, conversion‐type, and alloy‐type materials. Although intercalation‐type anodes suffer from limited capacity and conversion‐type materials are often plagued by poor electronic conductivity and severe voltage hysteresis, alloy‐type anodes have attracted increasing attention due to their high theoretical capacities, suitable operating potentials, and favorable intrinsic conductivity. Nevertheless, single‐metal alloy anodes (e.g., Sn, Bi, and Sb) typically undergo severe volume expansion during sodiation, leading to structural degradation and rapid capacity fade. To address these issues, extensive efforts have been devoted to developing modification strategies, including carbon compositing, structural engineering, electrolyte optimization, and the design of multicomponent alloy systems. In this review, we provide a comprehensive and systematic overview of alloy‐type anode materials for SIBs, covering single‐metal, binary (active–active and active–inactive), ternary, and higher‐order alloy‐type anode systems. The fundamental sodium storage mechanisms are summarized, while composition regulation strategies and structural design principles are critically discussed. Finally, the remaining challenges and future research directions toward practical applications are highlighted. This review aims to offer valuable insights into the rational design of high‐performance and commercially viable alloy‐type anodes for next‐generation sodium‐ion batteries.

Lithium–sulfur (Li–S) batteries represent promising energy storage devices by virtue of their ultrahigh theoretical energy density, yet their practical deployment is severely impeded by the polysulfide shuttle, sluggish sulfur redox kinetics, and progressive degradation of lithium anodes. Herein, we design a thiol‐functionalized UiO‐66 (UiO‐66‐SH)‐coated polypropylene separator that addresses these challenges simultaneously. The UiO‐66‐SH combines abundant coordinatively unsaturated Zr sites and SH groups, enabling both strong chemical anchoring of lithium polysulfides and catalytic acceleration of their conversion to Li2S. The modified separator exhibits superior electrolyte wettability, a high Li+ transference number (0.76), and enhanced ionic conductivity. Furthermore, it regulates lithium deposition to achieve a dendrite‐free anode and mitigates polysulfide‐induced corrosion. Consequently, Li–S cells incorporating UiO‐66‐SH/PP separator deliver an initial discharge capacity of 821.3 mAh g−1 at 1 C, retain 521 mAh g−1 after 500 cycles, and achieve a high‐rate capacity of 590.9 mAh g−1 at 5 C. Even under a high sulfur loading of 5.05 mg cm−2, a reversible capacity of 620.1 mAh g−1 is maintained after 200 cycles. This work offers a rational design of a multifunctional MOF‐based separator that integrates polysulfide entrapment, catalytic conversion, and anode protection, paving the way toward high‐performance, long‐life Li–S batteries.

MXene has emerged as a promising two-dimensional (2D) lubricant additive due to its layered structure, low interlayer shear strength, and tribochemical activity. However, their structural instability under oxygen-containing and high-temperature conditions often leads to oxidation and decomposition, which severely limits their practical use in lubrication systems. In this study, instead of suppressing this transformation, we harness the tribochemically induced in situ evolution of MXene to construct a self-adaptive lubricating interface for low friction and wear under oil lubrication. Comprehensive interfacial characterizations reveal that tribological loading drives the transformation of MXene into a highly graphitized carbon-rich tribofilm, while coordination interactions between oleic acid (OA) and MXene facilitate carbon reconstruction at the sliding interface. Reactive molecular dynamics (RMD) simulations further demonstrate that friction-induced shear promotes Ti-C bond dissociation and carbon graphitization, providing atomistic insights into the dynamic interfacial reconstruction process. The combined effects of tribochemical transformation and molecular coordination promote the formation and progressive reconstruction of a robust graphitized tribofilm, thereby sustaining low friction and enhancing wear resistance. This work provides new insights into the tribological behavior of MXene-based additives and highlights their potential for high-performance lubrication in advanced mechanical systems.

Lithium-rich manganese-based oxide (LRMO) cathode materials have emerged as promising candidates for next-generation lithium-ion batteries (LIBs) due to their high specific capacity and exceptional energy density. Nevertheless, their practical application is significantly hindered by pronounced voltage decay and capacity loss during cycling, which stem from complex and interrelated mechanisms. This review presents a comprehensive, multi-scale analysis of the degradation pathways in LRMO materials, spanning from atomic-level structural dynamics to mesoscopic heterogeneities and macroscopic particle evolution. Special focus is directed toward unraveling the synergistic interplay between oxygen anionic and cationic redox processes, oxygen release, transition metal ions (TMs) migration, irreversible phase transitions, heterogeneous electrochemical reactions, and operational conditions. By integrating insights from advanced characterization, theoretical modeling, and electrochemical analyses, this review establishes a cohesive framework that elucidates the intricate relationships among oxygen activity, TMs dynamics, and structural transformations. These mechanistic insights lay a critical foundation for the development of stabilization strategies aimed at mitigating voltage decay and capacity loss. Ultimately, this review bridges the gap between fundamental mechanistic understanding and practical engineering applications, offering actionable guidance for the design of durable and high-energy-density LRMO cathode materials tailored for high-performance energy storage systems.

The growing reliance on batteries in modern society highlights the crucial role of separators in energy storage devices. As the demand for high-performance batteries increases, developing advanced separators─guided by a deep understanding of physical phenomena and structure-property relationships─becomes critical for next-generation energy storage systems. Recent developments in separator technology have evolved from simple polymer-based materials to sophisticated organic/inorganic composites. A key innovation in this field is the incorporation of inorganic particles into separators, which significantly improves their physical and chemical performance. Among these inorganic additives, zeolites and other porous materials stand out due to their ordered pore structures, high porosity, large specific surface areas, and excellent thermal stability. This review highlights the chemical and physical properties of zeolites that make them valuable for designing composite separators. We explore the engineering of polymer/zeolite composite separators, with an emphasis on enhancing mechanical strength, increasing ionic conductivity, and promoting favorable chemical interactions. Furthermore, we evaluate the suitability of synthetic zeolites in various types of energy storage systems, focusing on their structural and thermal advantages relevant to separator performance. Finally, we discuss future research directions, potential technological advancements, and the challenges associated with integrating zeolites into catalysts, adsorbents, battery separators, and solid-state electrolytes.

Simultaneously achieving stable lithium metal batteries (LMBs) under cryogenic and high-voltage conditions remains a fundamental challenge due to uncontrolled interfacial chemistry at lithium anodes and nickel-rich cathodes. Here, we report an intramolecular polarization strategy that jointly regulates Li+ solvation dynamics, solid electrolyte interphase (SEI) formation, and cathode electrolyte interphase (CEI) stress dissipation. An intramolecularly polarized electrolyte featuring orthogonally arranged electron donor-acceptor moieties with a dipole moment (∼4.2 D) establishes a potential-dependent solvation screening effect, reducing Li+ desolvation energy to 38.1 kJ mol-1, while enabling anodic stability beyond 5.3 V. The tailored solvation chemistry induces spontaneous formation of dual-gradient interphases composed of a LiF-rich SEI and a boroxane-incorporated CEI with an interface modulus ∼20 nN. Consequently, Li||Li symmetric cells exhibit stable cycling over 16 000 h with a minimal polarization of 8.3 mV. Full cells employing LiNi0.8Co0.1Mn0.1O2 cathodes retain 90% capacity after 1000 cycles at 4.5 V and maintain 80% at 4.9 V. 3 Ah pouch cells achieve a high energy density of 509 Wh kg-1 at 30°C with 96.8% capacity retention after 80 cycles, while delivering 439.1 Wh kg-1 at -30°C. This work establishes a molecular polarization paradigm for electrolyte and interphase engineering toward high-energy-density LMBs under extreme conditions.

The pursuit of high-energy-density lithium-sulfur (Li-S) batteries necessitates the use of lean electrolyte conditions. However, this goal is severely hampered by the sluggish kinetics of the sulfur reduction reaction (SRR), especially in the "solid-solid" conversion stage, where each step requires distinct active sites with specific electron-donating capabilities. Herein, we report a catalyst architecture that integrates "long-range order" with "local disorder", creating gradient-ordered active sites through amorphous nanodomain modification and precise local electronic structure regulation. This catalyst, termed an electron-pinned interface catalyst (EPIC) and denoted as a-FeOOH@Fe/AlOx, exhibits synergistic catalytic enhancement via multi-level electronic interactions. Operando studies and DFT simulations reveal that the catalyst establishes conductive pathways facilitated by its gradient electron-donating properties, thereby decoupling the SRR process and significantly enhancing the "solid-solid" conversion efficiency. Under lean electrolyte conditions, this catalyst achieves a high areal capacity of 10.7 mAh·cm-2 at a sulfur loading of 10.2 mg·cm-2, exhibits 94.2% capacity retention after 150 cycles in a pouch cell, and enables stable operation of a 3.6 Ah pouch cell with an energy density of 418.6 Wh·kg-1. This strategy effectively overcomes the reaction kinetic limitations in lean electrolyte conditions, providing valuable insights and a novel design paradigm for future high-energy-density Li-S batteries.

Construction of an advanced current collector with optimized structure and multi-functionality is critical for solving the thorny problems (e.g., lithium polysulfides (LiPSs) shuttle effect, low conductivity, and sluggish sulfur conversion) of Li-S batteries. Unlike the use of an conventional pore-free 2D current collector (low sulfur loading) or the 3D current collector rich in irregular macropores (poor sulfur fixation ability), herein a hierarchically porous current collector (HPCC) with tailored pore architecture and multifunctionality is designed, which is constituted by a large-pore 3D carbon cloth (CC) substrate (pore size > 50 & micro;m), conjugated microporous conducting polymers (CMPs) filler materials (pore size 0.8-1.6 nm) and Pd nanopaticle catalysts (3-5 nm). The HPCC optimizes the original large-pore 3D CC structure into a hierarchically porous structure with regularized pore size and uniform catalytic sites, achieving a 2D/3D functional balance. Benefiting from the enhanced Li+/e(-) transportation, high-efficiency LiPSs adsorption, and strong catalysis ability for LiPSs, the batteries with HPCC achieve the ultrahigh discharging capacity of 1304 mAh g(-)(1) at 0.2 C, exceptional stability (0.42% decay/cycle at 10.59 mA & centerdot;cm(-)(2)) even at a high sulfur loading condition of 10.3 mg cm(-)(2), and good commercial application potential (driving electric-car operation). This pore engineering strategy establishes a paradigm for developing a high-energy-density battery.

Modulating interfacial ion transport via separator engineering is pivotal for overcoming the rate capability and cycle life limitations of lithium metal batteries (LMBs). Although polarity-tuning strategies have been widely explored, a clear physical linkage between molecular-level design and transport kinetics, particularly as quantified by Sand's time, remains unresolved, making separator optimization largely empirical. Herein, we report a systematic series of isoreticular covalent organic frameworks (COFs) that decouple pore topology from electronic effects and introduce framework electronegativity (χ) as a quantitative descriptor for ion-selective transport. By modulating χ, exemplified through progressive fluorination, a push-pull electrostatic microenvironment is established that promotes Li+ transport while repelling PF6-, thereby suppressing concentration polarization and revealing an effective scaling relationship between χ and Sand's time. Guided by this descriptor, an optimized TFCOF@PP separator increases the Li+ transference number by 73% and markedly suppresses concentration polarization, enabling stable cycling of LiFePO4 full cells at 5 C with 83.1% capacity retention after 4000 cycles. The system further demonstrates robust performance under demanding conditions, including high-voltage NCM811 cells, elevated temperatures (60 °C), and mechanical abuse. This work elucidates the physical origin linking framework electronegativity to interfacial transport kinetics, providing a rational, descriptor-based strategy for separator design to mitigate kinetic failure in metal batteries.

Spatial heterogeneity at electrode/electrolyte interfaces critically influences the electrochemical performance and degradation of lithium-ion batteries, yet the respective contributions of surface morphology and interfacial chemistry to localized electrochemical kinetics remain...

FeV2S4 holds promise as an anode for sodium-ion batteries (SIBs) because of its large interlayer spacing, high storage capacity, and metallic conductivity. However, the significant volume expansion and polysulfides dissolution during cycling usually lead to material pulverization and performance degradation. Herein, the thin N-doped carbon (NC) layer encapsulated FeV2S4/Fe nanorods (FeV2S4/Fe@NC) have been constructed via the multi-step strategy. Under the synergistic effect of outer NC and inner FeV2S4/Fe, the optimized FeV2S4/Fe@NC anode prepared at 850 degrees C demonstrates fast-charging sodium storage capabilities (525 mAh g-1/2 A g-1/400 cycles and 281 mAh g-1/15 A g-1). Remarkably, except for 25 degrees C, such well-chosen anode can easily run at extreme temperatures, demonstrating excellent all-climate rate capabilities (135 mAh g-1/5 A g-1 at 0 degrees C and 289 mAh g-1/15 A g-1 at 40 degrees C) and cyclic stability (371 mAh g-1/0.5 A g-1/200 cycles at 0 degrees C and 529.2 mAh g-1/2 A g-1/300 cycles at 40 degrees C). Additionally, the components of SEI film, electrochemical kinetics, theoretical calculations, and various in-situ/ex-situ characterizations confirm the rapid charge transfer, highly efficient Na+ diffusion, and conversion-based reaction mechanism in FeV2S4/Fe@NC. Furthermore, the full cells consisted of FeV2S4/Fe@NC anodes and reduced graphene oxide modified Na3V2(PO4)3 (Na3V2(PO4)3@rGO) cathodes realize satisfied electrochemical performances (242 mAh g-1 over 140 cycles at 1 A g-1). This work offers a rational synthesis approach for designing high-performance dual-metal chalcogenide-based anodes for sodium-ion storage.

In recent years, halide perovskite quantum dot (PQD) solar cells have garnered more research interest, yet poor operational and environmental stability limit their commercialization. Herein, a robust all-perovskite low-dimensional (LD)/PQD heterojunction is proposed to address these issues. In particular, rationally designed 2D perovskite single crystals dissolved in optimized solvents are directly coated on the PQD matrix to drive spontaneous conformal LD prototype growth. Notably, this strategy features a heating-free procedure with negligible erosion characteristics. Benefiting from the well-matched energy-level alignment at the intimate heterojunction, interfacial charge extraction is synergistically promoted, while a defect-free 2D single-crystal layer suppresses humidity-induced degradation via effective encapsulation. With this engineered LD/PQD heterojunction, the optimized FAxCs1-xPbI3 PQD device delivers a champion efficiency of 17.6% (certified value of 16.98%), with 9-fold enhanced humidity stability versus that of the pure PQD analogue. This work provides a novel heterostructure construction paradigm and mechanistic guidance for improving the efficiency and environmental stability of PQD-based optoelectronic devices.

ABSTRACT Spent graphite (SG) from end‐of‐life lithium‐ion batteries suffers from persistent structural disorder, yet the defect chemistry governing its regeneration remains poorly understood. Here, we identify carbon vacancies and quasi‐sp 3 topological defects as the dominant degradation motifs and leverage this insight to devise a defect‐targeted regeneration strategy. Under electrothermal coupling enabled by flash Joule heating in a CoCl 2 molten‐salt medium, cobalt species are selectively directed to defect sites, where strong Co‐defect interactions reduce the energy barrier for topological reconstruction. The resulting Co‐induced charge redistribution activates quasi‐sp 3 ‐carbon via population of π * antibonding states, while thermally assisted and field‐directed carbon migration promotes its conversion into a more ordered sp 2 ‐rich lattice. Concurrently, residual interphases and impurities are eliminated, lattice stress is relieved, and the cobalt catalyst is efficiently recovered. The regenerated graphite (RG) delivers a capacity of 257 mAh g −1 after 1000 cycles at 1 A g −1 , corresponding to 83% retention relative to the post‐activation capacity, and outperforms commercial graphite under identical conditions. This work establishes a chemically informed route for the rapid upcycling of SG through defect‐selective topological repair.

ABSTRACT Single‐atom catalysts (SACs) play a critical role in diverse catalytic applications, but their efficient synthesis remains a significant challenge. Herein, we develop an ultrafast magnetic‐field‐enabled quench (MFEQ) strategy to synthesize a series of M 1 /G‐FeO x (M═Ni, Fe, Co, Ir, Ru, and Pt) SACs within a few seconds. Using Ni 1 /G‐FeO x as a proof of concept, this method leverages the rapid quenching of thermally incandescent Fe foam into an Ni‐containing ethanol solution, triggering simultaneous graphene formation and Ni anchoring. The Ni 1 /G‐FeO x catalyst shows exceptional alkaline oxygen evolution reaction (OER) performance, operating at 200 mV for 10 mA cm −2 and sustaining 105 mA cm −2 for 330 h without degradation. Notably, the Ni 1 /G‐FeO x ‐catalyzed anion exchange membrane water electrolysis (AEMWE) device exhibits a low voltage of 1.86 V at 1.0 A cm −2 and 600 h long‐term stability. Density functional theory (DFT) calculations and experiments reveal that the strong electronic interactions between Ni 1 /G and FeO x contribute to the optimized electronic structure and reduced energy barrier. Techno‐economic analysis (TEA) highlights the superior energy efficiency of the MFEQ method, which requires only US$19.2 in energy expenditure to synthesize 1 kg of SACs. This work provides new insights into the ultrafast fabrication of SACs.

Direct regeneration of spent layered ternary oxide cathodes offers a sustainable pathway for resource recovery and circular battery manufacturing. However, their long‐term stability is fundamentally constrained by intrinsic electronic interactions. In particular, the inherent π‐type hybridization between Ni 3 d orbitals and O 2 p orbitals facilitates detrimental Ni migration and rock‐salt phase formation, ultimately leading to rapid capacity degradation. Here, we leverage the preexisting Li vacancies in spent LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM) as orientation sites to induce localized lattice stress fields during regeneration. The resulting lattice perturbation modulates the spin configuration of bridging O anions, thereby triggering antiferromagnetic coupling between adjacent Ni cations and O anions. Consequently, the Ni─O orbital hybridization transitions from weak π‐dominated to robust σ‐dominated interactions, as evidenced by enhanced covalent character of the Ni─O bonds. This reinforced bonding framework effectively suppresses Ni migration and defect propagation during repeated lithiation/delithiation cycles. As a result, the regenerated NCM cathode exhibits significantly improved durability, retaining ∼60% of its initial capacity after 750 cycles. These findings reveal a direct correlation between the local valence bond evolution and cycling reversibility of cathode materials, offering new design principles and mechanistic insights for stabilizing regenerated cathode materials.

Rational design of cost-effective atomic cluster (AC) catalysts with high mass activity and robust durability remains a huge challenge for the practical alkaline hydrogen evolution reaction (HER), primarily due to sluggish water dissociation kinetics at the electrolyte/electrode interface and inherent tendency of ACs to agglomerate. Herein, we report a design concept by employing NbOx nanoislands anchored on fullerene-derived carbon (FDC) to spatially confine and stabilize Os ACs and enhance interfacial water dissociation ability for efficient alkaline HER catalysis in an anion exchange membrane water electrolysis (AEMWE). We find that the NbOx nanoislands create a structurally confined environment that induces strong interfacial metal-support interactions for stabilizing the Os ACs against aggregation and enhancing the operational stability. Moreover, oxophilic NbOx domains optimize interfacial water organization with enriched "free" hydrogen-bonded water at the reaction interface and strengthen the adsorption of hydroxyl species to accelerate water dissociation for a sufficient proton supplement. The resulting NbOx-Os@FDC catalyst achieves an ultralow overpotential of 14 mV at 10 mA cm-2 and an exceptional mass activity of 2.42 A mgOs-1 at -0.1 V vs RHE. Particularly, NbOx-Os@FDC-based AEMWE with an ultralow Os loading realizes an industrial-level current density of 1 A cm-2 at 1.74 V with high durability.

Direct regeneration is considered a sustainable solution to the issue of resource recycling and the environmental pollution caused by discarded lithium-ion batteries (LIBs). However, the direct regeneration of spent LiFePO4 cathode materials still faces a formidable challenge that the irregular strains induced by the irreversible FePO4 phase after several charge and discharge cycles hinder the regenerative replenishment of Li+. This work proposes a lattice stress modulation strategy that reduces FePO4 phase into Fe2P2O7 phase (reduction of unit cell volume from 271.7 to 122.6 Å3), which releases the residual stress, paving continuous transport channels for Li+. In addition, the phase transformation reconstructs the FeO6 octahedra, significantly decreasing the migration energy barrier of ions within the lattice. Ultimately, the steric effect is synergistically weakened, facilitating the replenishment of Li+ and the elimination of Li-Fe anti-site defects. The regenerated LiFePO4 cathodes outperform commercial cathodes (80.2

The Christiansen effect, owing to its unique wavelength-selective scattering characteristics, exhibits significant application potential in fields such as optical modulation, biomimetic structural coloration, sensing and smart windows, and is gradually transitioning from theoretical research to functional material development. Here, we review the latest research progress of Christiansen structural color materials, from fundamental physical mechanisms to multidimensional dynamic regulation. It focuses on comparing fluidic platforms dominated by compositional and thermodynamic control, as well as solid-state architectures including rigid composite materials, open-framework infiltration and in situ component locking strategies, revealing the limitations and advantages of different physical morphologies in terms of material stability and functional integration. On this basis, the review delves into multidimensional color-tuning strategies based on the Christiansen effect, covering both the molecular structural changes and the modulation of physical fields, including electric, thermal, and optical fields. Finally, the review provides an interdisciplinary research perspective, discussing the application of the generalized refractive index matching mechanism in biological tissue transparency and industrial device integration, and outlines the future development direction of Christiansen structural colors from fundamental property regulation toward high-performance, integrated devices.

The rapid growth of lithium-ion batteries has intensified the need for efficient recycling of spent LiNi0.5Co0.2Mn0.3O2 (NCM) cathodes. However, direct regeneration is hindered by the high-spin state of Ni2+ (S = 1) in degraded surface structures, which impedes Li+ intercalation and limits repair efficiency. Here, we introduce a strong electronegative ligand field to modulate the surface NiO6 coordination environment, enabling precise regulation of Ni spin state and electronic structure. This strategy alters the occupancy of Ni eg orbitals, converting high-spin Ni2+ (t2 g 6eg 2, S = 1) to low-spin Ni3+ (t2 g 6eg 1, S = 1/2) while downshifting the Ni d-band center. The resulting electronic reconfiguration weakens Ni-Li interactions, enabling efficient lithiation and regeneration of the degraded NCM black mass. The regenerated cathode, when assembled into pouch cells, exhibits Ah-level capacity with electrochemical performance comparable to commercial counterparts. This work establishes a direct correlation between Li+ transport kinetics and the Ni spin-state regulation, offering a new chemical paradigm for the direct regeneration of degraded cathodes.

ABSTRACT Solid‐phase regeneration is widely considered as the most promising scalable approach for recycling spent LiFePO 4 (S‐LFP) cathode. However, the sluggish defect‐repair kinetics in traditional solid‐phase routes remains mechanistically unclear, limiting the practical deployment of this technology. Here, theoretical calculations reveal that the phonon localization in defect‐rich S‐LFP is the essential factor responsible for the sluggish defect‐repair kinetics. Localized phonons retard thermal diffusion, hindering the energy available to overcome defect repair barriers, and concurrently intensify electron‐phonon coupling that suppresses the electron migration necessary for the reduction of Fe(III). Guided by this insight, we employ electric/thermal coupling field strategy to repair the S‐LFP cathode. Carriers driven by the electric field transfer energy to phonons through electron‐phonon scattering, which promotes energy redistribution across disparate phonon modes, collectively enhancing phonon delocalization. As a result, Li‐Fe antisites (Fe Li ) were repaired within 5 s at 700°C, and the complete structural repair and lithiation are achieved within 60 s. Experimental results indicate that the regenerated cathode delivers a discharge specific capacity of 151.2 mAh g −1 at 0.1C, and exhibits a capacity retention of 84.3% after 1100 cycles at 1 C. This theoretical breakthrough establishes a solid theoretical foundation for developing advanced S‐LFP restoration technologies.