Cathodes integrating high energy density and durable long-term cycling stability under varied conditions play a crucial role in sodium-ion batteries (SIBs). Herein, we report a synergistic design strategy involving Cr3+/Al3+ co-substitution and N-doped carbon coating to construct flower-like Na3V2-x(CrAl)x(PO4)3@NC (NVCAP-x) cathodes that address the inherent constraints of NASICON-type Na3V2(PO4)3 (NVP). Systematic structural analyses reveal that Cr3+ (d3) and Al3+ (d0) co-substitution induces controlled lattice contraction, shortening the average metal–oxygen bond length from 1.998 Å to 1.977 Å, thereby reinforcing framework rigidity. This lattice modulation enables reversible utilization of the high-voltage V4+/V5+ redox couple at ∼3.95 V, while the rigid [AlO6] octahedra effectively accommodate local strain from ionic-radius mismatch and V4+/V5+ ionic radius contraction, preserving long-range NASICON symmetry during cycling. The conformal N-doped carbon layer (∼5 nm) establishes dual interfacial protection: physically blocking direct electrode-electrolyte contact and chemically anchoring surface V species via pyridinic-N coordination, which may help mitigate vanadium dissolution. The optimized NVCAP-0.1 cathode achieves near-theoretical reversible capacity (114.9 mAh g−1 at 1C) through the concurrent activation of V3+/V4+ (∼3.4 V) and V4+/V5+ (∼3.95 V) redox couples, maintaining 91.7% capacity after 15,000 cycles even at 100C. Notably, the electrode shows wide-temperature tolerance, delivering 75.9 mAh g−1 after 750 cycles at −20 °C (5C) and 121.4 mAh g−1 at 55 °C (1C). The assembled hard carbon (HC)//NVCAP-0.1 full-cell further validates practical viability, powering a light-emitting diode and maintaining >76% capacity after 100 cycles at 5C.

Solid polymer electrolytes (SPEs) hold immense promise for next-generation lithium metal batteries, yet their progress is fundamentally hampered by an intrinsic trade-off between ionic conductivity and mechanical strength, further exacerbated by uncontrolled anion migration. Herein, we report a rationally designed composite SPE that transcends these limitations through a synergistic dual-anchor strategy. By integrating lithium titanate (Li4Ti5O12, LTO) nanoparticles with two functional sites on their surface into a thermoplastic polyurethane/polycarbonate matrix, we create a multifunctional network. In this network, (i) Lewis-acidic Ti4+ sites on LTO selectively immobilize TFSI- anions, promoting LiTFSI dissociation and yielding a high lithium-ion transference number (t(Li)(+)) of 0.73, thereby suppressing space-charge layer effects; (ii) hydroxyl groups on LTO form dense hydrogen bonds with polymer carbonyls, constructing a robust framework that enhances tensile strength to 4.1 MPa without disrupting continuous ion-conduction pathways. This design enables the synergistic enhancement of ionic conductivity and mechanical properties, resulting in an exceptional ionic conductivity (1.26 mS cm(-1)) at 30 degrees C, a low activation energy (0.195 eV), and a wide electrochemical stability window (5.0 V). Consequently, the Li parallel to Li symmetric cell demonstrates ultralong cycling stability over 1600 h at 0.5 mA cm(-2). When paired with a LiFePO4 cathode, the full cell delivers outstanding rate capability and retains 92% of its initial capacity after 330 cycles at a high rate of 2 C. This work not only presents a high-performance SPE but also establishes a versatile design paradigm that leverages coupled Lewis-acidic and hydrogen-bonding interactions to overcome the long-standing strength-conductivity dilemma in solid-state electrolytes for dendrite-free lithium metal batteries.

Element doping-sulfidation synergy enables electronic modulation and exposure of active sites, which are vital for efficient and stable bifunctional electrocatalysts in green hydrogen production. This study reports the synthesis of a 3D microflower-like NiFeMn-S catalyst via hydrothermal synthesis of Mn-doped NiFe layered double hydroxides (NiFe-LDH), followed by sulfidation. Mn doping induces valence shifts of Ni/Fe and the oxidation of Mn to Mn3+/Mn4+, forming multivalent synergy for Ni/Fe/Mn electronic interactions, tuning the electronic structure, and boosting charge transfer; sulfidation forms Ni3S4/FeS multiphase coupling, with interfacial effects optimizing intermediate adsorption-desorption and reaction pathways, and the 3D microflower-like nanosheet structure mitigates structural collapse and enhances stability. NiFeMn-S exhibits superior catalytic activity and stability compared to pristine NiFe-LDH, requiring merely 1.6 V cell voltage to drive electrochemical water splitting in alkaline media. This research provides novel insights into designing high-performance non-precious metal catalysts through multidimensional modification.

Zinc-ion batteries (ZIBs) are constrained by vanadium-based cathodes with limited capacity and poor structural stability. Herein, Al-doped V2O3@ nitrogen-doped carbon (Al-V2O3@NC) microspheres, synthesized via hydrothermal and annealing processes, are engineered to address these issues through multi-scale modifications. Specifically, Al doping induces robust Al-O bonds to mitigate volume expansion during Zn2+ (de)intercalation and generates abundant oxygen vacancies, enhancing active sites and electron transport. The conformal NC coating preserves morphology and accelerates charge transfer. In-situ activation transforms Al-V2O3@NC into Al-V2O5nH(2)O@NC, delivering 495.3 mAh g(-1) at 0.2 A g(-1), 348.4 mAh g(-1) at 10.0 A g(-1), and 75.5 % retention after 6000 cycles at 10.0 A g(-1), which is attributed to the synergistic effects of the stabilized Al-O framework, accelerated ion diffusion, and pseudocapacitive-dominated charge storage (with capacitive contributions exceeding > 90 % at 1.0 mV s(-1)). This work provides a versatile strategy for optimizing vanadium-based cathodes in high-performance aqueous ZIBs.

Aqueous zinc-ion batteries (ZIBs) are bottlenecked by vanadium-based cathodes with inferior conductivity, sluggish Zn2+ transport, and structural instability. Herein, we design Zn-doped V2O3@C (Zn-V2O3@C) nanorods via MOF-derived annealing, integrating Zn evaporation-coupled doping and V2O3@C heterostructure engineering. The V2O3@C heterointerface with a built-in electric field (BIEF) accelerates internal electron transfer; residual Zn dopants (Zn: V = 0.037) induce lattice expansion (unit cell volume expanded by 1.51 Å3 after doping) and oxygen vacancies, narrowing the band gap to 0.56 eV and reducing Zn2+ diffusion barrier to 0.12 eV, which synergistically optimizes electronic structure and ion transport kinetics. Given the aforementioned strategies, the cathode delivers superior rate capability, with 422.8 mAh g-1 at 0.2 A g-1 and 265.8 mAh g-1 even at 10.0 A g-1. This versatile evaporation-doping strategy serves as a valuable reference for modulating high-performance ZIB cathodes.

The development of solid-state polymer electrolytes is severely hampered by the persistent trade-off among ionic conductivity, flame retardancy, and electrochemical stability. While poly(ethylene oxide) (PEO) offers good Li+ solvation, its high crystallinity impedes room-temperature ion transport, and its inherent flammability poses safety risks. Existing modification strategies often improve one property at the expense of others. Herein, we break this long-standing three-way conflict through the molecular/structural design of a phosphorylated poly (vinyl alcohol) (PVA)/PEO semi-interpenetrating polymer network (PPB-FR). Our first key innovation lies in the construction of this unique architecture, which simultaneously suppresses the crystallinity of PEO (from 84.5% to 24.8%) and establishes a continuous flame-retardant framework, thereby bypassing the issue of additive-blocked ion pathways. The second, mechanistic innovation is the creation of a "phosphoryl-group-bridged" dual-ion conduction mechanism. Combined DFT calculations and solid-state 7Li NMR reveal that while Li+ migrates along amorphous PEO chains, the phosphoryl groups act as critical "relay stations" (lowering the local hopping barrier) to bridge transport across otherwise obstructed regions. This synergistic mechanism enables a high lowtemperature ionic conductivity of 2.25 & times; 10-4 S cm-1 and a high Li+ transference number of 0.547. The third innovation is the multi-functionality of the phosphoryl groups, which integrate intrinsic flame retardancy (LOI of 32.4%), structural reinforcement (tensile strength of 59 MPa), and in situ formation of a LiF/Li3PO4-rich stable solid electrolyte interphase. Consequently, Li symmetric cells demonstrate exceptional durability over 600 h under step-increased current densities up to 1.5 mA cm- 2, and LiFePO4 full cells deliver remarkable rate capability and cycling stability.

Two-dimensional layered VS2 is a promising anode material for lithium-ion batteries (LIBs) with a high theoretical capacity, yet its practical application is plagued by low electrical conductivity and severe volume expansion during cycling. Herein, we report a novel synergistic strategy integrating NH3 pre-intercalation, interlayer in-situ polymerization of polypyrrole (PPy), sulfur vacancy (Vs) engineering to fabricate a hierarchical NH3 & sdot;VS2-x/S8@PPy composite anode. The pre-intercalated NH3 expands the interlayer spacing from 5.6 & Aring; to 9.7 & Aring;, enabling smooth diffusion of pyrrole monomers into the interlayers for in-situ polymerization; meanwhile, the strong oxidizability of pyrrole cation radicals induces partial desulfurization of VS2, generating both Vs and S8. Comprehensive structural characterizations (XRD, TEM, Raman, and XPS) confirm that PPy chains are uniformly inserted into VS2 interlayers, Vs are homogeneously distributed in the VS2 lattice, and S8 is embedded in the composite matrix. The PPy-VS2 organic-inorganic interface electric field (OIIEF) synergizes with S vacancies to boost electrochemical kinetics via charge transfer. Density functional theory (DFT) calculations reveal that interlayer PPy and Vs synergistically optimize the electronic structure of VS2 (band gap reduced from 0.417 eV to 0 eV), enhance Li+ adsorption energy (from -2.68 eV to -3.44 eV), and lower Li+ diffusion barrier (from 1.01 eV to 0.80 eV), thereby accelerating charge/ion transport kinetics. Electrochemically, NH3 & sdot;VS2-x/S8@PPy delivers a high reversible capacity of 822 mAh g- 1 at 0.2 A g- 1 after 200 cycles and maintains 561 mAh g- 1 even at 1 A g- 1 after 1000 cycles, outperforming pristine VS2 and single-modified counterparts. This work demonstrates the critical role of multiscale regulation (interlayer expansion, defect engineering, and interface modulation) in overcoming the intrinsic limitations of layered sulfide anodes, providing a universal design reference for highcapacity and long-life LIB anode materials.

The commercialization of aqueous zinc-ion batteries is hampered by a fundamental paradox: electrolytes with anti-freezing properties typically lack self-healing capability, and vice versa. Herein, we decouple this trade-off through the ingenious design of a synergistic network within a eutectogel electrolyte. This network is governed by strong Zn2+ coordination acting as rigid anchors, coupled with a dynamic quaternary hydrogen-bond (HB) network involving glycerol, ClO4 -, water, and polyacrylamide serving as flexible bridges. In this configuration, the strong Zn2+ coordination and dense hydrogen bonds synergistically inhibit ice lattice formation to ensure anti-freezing, while the reversible hydrogen bonds enable dynamic molecular reconfiguration for self-healing. The resulting gel remains ice-free at -75 degrees C and self-heals within 10 min even at -20 degrees C. Concurrently, this unique structure reconstructs the Zn2+ solvation sheath, significantly reducing the water coordination number from 3.65 to 2.62, which effectively suppresses water-induced parasitic reactions. Coupled with robust in situ interfacial engineering, the assembled battery exhibits a high specific capacity and exceptional cycling stability (97.0% capacity retention after 1000 cycles at 5 A g-1) over a wide temperature range of 80 degrees C (-20 degrees C-60 degrees C). This work not only provides a high-performance electrolyte for practical zinc batteries but also establishes an innovative design paradigm for resolving property conflicts in advanced functional materials.

Volume expansion and interfacial instability in transition metal selenides limit the realization of their high theoretical capacity in lithium/sodium-ion batteries (LIBs, SIBs). This work reports an in-situ electrochemical reaction-triggered structural evolution that transforms Fe3Se4/MnSe heterostructures encapsulated in N, Se co-doped hollow carbon nanospheres into soft-rigid components. This approach breaks away from conventional static electrode designs by introducing a dynamic in-situ reconstruction strategy. Through atomically precise electronic regulation and multi-scale structural engineering, it effectively overcomes inherent limitations. Specifically, the material undergoes a unique "tailored phase transformation": Fe3Se4 transforms into an amorphous structure, acting as a soft component to ensure rapid ion dynamics; meanwhile MnSe transforms from the α-phase to the β-phase with high degree of crystallinity, serving as a mechanical stabilizer to withstand volume strain. Furthermore, density functional theory calculations indicate that this heterostructure achieves an optimized d-band center (-0.277 eV), which acts as an electron regulator to enhance interfacial chemical bonding while simultaneously lowering the activation energy barrier for ion insertion/extraction. Consequently, the anode exhibits outstanding electrochemical properties: under the current density of 2 A g-1 maintaining a capacity of 714 mAh g-1 for LIBs and 252 mAh g-1 for SIBs after 1500 cycles.

Two-dimensional (2D) layered VS2 is a promising lithium-ion batteries (LIB) anode for high capacity but is limited by low conductivity and severe volume expansion in cycling. By using the solvothermal method, this study presents a synergistic modification strategy: W6+ (1.37 & Aring;) doping substitutes V4+ (1.31 & Aring;) to induce lattice distortion and sulfur vacancies, reducing interfacial charge-transfer resistance (R ct) from 946.8 to 147.8 Omega. Simultaneously, NH3 preintercalation expands the interlayer spacing from 5.7 to 9.7 & Aring;, enabling in situ pyrrole polymerization and Li+ diffusion. Annealing at 600 degrees C converts interlayer polypyrrole to N-doped carbon (60.7% pyrrolic N, 31.7% pyridinic N), forming a VS2 structure featuring rigid nitrogen-doped carbon (NC) interlayers, which enhance conductivity and buffer structural stress during cycling. The obtained VS2 after W-doping and NC intercalation (W-VS2@NC) demonstrates 705 mAh g-1 at 1 A g-1 (93% retention over 1000 cycles) and 526 mAh g-1 even at 5 A g-1. Mechanistic analyses confirm that W-doping introduces XPS-validated V3+/V2+ heterovalence for rapid electron transport, interlayer carbon layers (9.2 & Aring; spacing) buffer volume changes via a "spring effect", and N-doping (7.6% quaternary N) provides extra Li+ adsorption sites. This work presents a strategy for the synergistic optimization of conductivity and structural stability in layered sulfide anodes.

Despite their environmental friendliness, security and high volumetric energy density of zinc anodes, aqueous Zinc-ion batteries (AZIBs) still face poor reversibility of Zn anodes, especially under high current density, originating from various parasitic reactions induced by high activity of water. The hydrated deep eutectic electrolyte (HDEE) effectively suppresses parasitic reactions, but the electrochemical performance still needs to be optimized. Here, our research emphasized the importance of balancing enhanced reversibility and fast Zn2+ transfer kinetics. A new green and low-cost HDEE (Zn(ClO4)(2)6H(2)O/Glycerol) is developed, and then an optimized solvation structure [Zn(H2O)(2.0)(Gl)(1.3)(ClO4)(2.7)](2)(+) can be formed by adding glycerol (Gl), which not only maintains a high Zn2+ diffusion coefficient (1.2 x 10(-7) cm(2) s(-1)), but also disrupts the bulk water network via strong H-bonding with ClO4- and water, significantly lowering the freezing point (-65 degrees C) and inhibiting the parasitic reactions/cathode dissolution. Furthermore, the evolution of the HDEEs solvation chemistry and its impact on the electrode/electrolyte interfacial stabilities can be understood through precise adjustments of the molar ratios of Zn(ClO4)(2)6H(2)O and Gl, molecular dynamics and COMSOL simulation. The Zn//Zn with the HDEE (Zn|HDEE|Zn cells) can cycle for similar to 5000 h without short-circuiting at 1 mA cm(-2), which is roughly 12.5 times more stable than ordinary aqueous electrolyte, indicating effective suppression of parasitic reactions. The Zn//NH4V4O10 with HDEE (Zn|HDEE|NH4V4O10 cells) can stably cycle 3500 cycles with 120 mAh g(-1) at 10 A g(-1) at room temperature and 1000 cycles with 95 mAh g(-1) at 5 A g(-1) at a low temperature of -20 degrees C. This study provides a path toward the development of HDEE electrolyte and a thorough comprehension of the influence of Zn2+ solvation structure on reversibility.

The organic molecule of phytic acid is innovatively utilized to block the edges of partial MoS2 with steric effect to achieve differential intercalation of polypyrrole. After annealing, the intercalated MoS2 nanosheet retains the 1T phase with a large spacing of 0.98 nm, while the unintercalated regions transform into the 2H phase with a small spacing (0.62 nm), thus forming a 1T-2H MoS2 heterostructure. This structure integrates the high electrochemical activity of the 1T phase with the excellent stability of the 2H phase. Furthermore, MoS2 nanosheets are anchored by nitrogen-doped carbon (NC) nanotubes and coated with a N/P co-doped carbon (NPC) protective layer, forming a unique sandwich hierarchical structure (NC@T/H-MoS2@NPC). The synergistic effect of the 1T-2H MoS2 heterostructure and the unique hierarchical structure enhances ion diffusion kinetics and structural integrity. This electrode demonstrates remarkable cycling life, with 8 000 cycles at 10 A g-1 in Li-ion batteries and 15 000 cycles at 5 A g-1 in Na-ion batteries. The 1T and 2H phases exhibit different storage Na+/Li+ behaviors under ex situ X-ray diffraction tests. The density functional theory results reveal the heterostructure and NC layer modulate the Fermi level, reducing Li+/Na+ migration energy barrier and optimizing energy storage.

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Doping heterogeneous atoms can modulate electronic structure, which matters for creating efficient bifunctional electrocatalysts in realizing conversion of hydrogen and electricity. This study demonstrates that Fe-doped Ni5P4 nanosheet arrays on nickel foam (Fe-Ni5P4/NF) using Prussian blue analogues as precursors are successfully synthesized by straightforward hydrothermal reactions and phosphating. Fe-Ni5P4/NF exhibits great efficiency in creating hydrogen from water under alkaline conditions. The Fe-Ni5P4/NF dual electrode just need a minimal cell voltage of 1.54 V at 10 mA cm(-2) and maintain operational stability for a minimum of 50 h, demonstrating outstanding bifunctional properties. The introduction of Fe modifies the electronic configuration for Ni5P4, substantially boosting the activity of the electrocatalyst. This study offers a framework for designing splendid bifunctional electrocatalysts through synergistic doping strategies in electrochemical applications.

A recyclable hard-template method is proposed to exploit spindle-shaped hollow nitrogen-doped amorphous carbon (h-NAC) with a large number of short-range curved carbon fragments as anodes for lithium/sodium ion batteries (LIBs/SIBs). Besides providing adsorption sites due to the high existence of oxygen-containing functional groups (-CO and -COOH), the heavily exposed edge regions also provide a favorable storage environment with high adsorption energy for Li+/Na+ due to their short-range curved structure. Importantly, the etching solution of hard templates can be recycled to generate the FeOOH nanospindles as a precursor through a simple chemical titration, which supplies a new idea for the green preparation of hollow materials. The h-NAC electrode is proven to be bifunctional for storing lithium and sodium ions, displaying favorable rate capability (255 mAh g-1 and 106 mAh g-1 at 5 A g-1 for LIBs and SIBs, respectively). After 1000 cycles at 1 A g-1, the reproducible capacities of the LIBs and SIBs kept 496 mAh g-1 and 181 mAh g-1, respectively.

As active materials for large-radius Na+ storage, metal sulfide (MS) anodes still face several challenges, including poor intrinsic electric conductivity, severe volume change along with the shuttle and dissolution effects of discharge-produced polysulfides. In this work, the mixed nickel-manganese sulfides (NiMnS) in the morphology of uniform 2D ultrathin nanosheets are derived from layered metal-organic frameworks (MOFs), where the NiS-MnS heterojunction are accommodated in carbon matrix with S dopant (NiMnS/SC). Through experiments and density functional theory (DFT) simulations, it is revealed that the carbon matrix with S dopant has multifunctional effects on active NiMnS during the charge/discharge process, including conductive intermediary, electrochemical active site, physical barrier, and chemical adsorption. This work may promote the design of MS-based electrodes in SIBs and extend the application of carbon material with S dopant in Na-S batteries.

In this work, globular WS2/Co9S8 nanoflowers coated with nitrogen-doped carbon (NC) and anchored on nitrogen-doped porous graphene (NPG) foam (NPG@WS2/Co9S8@NC) were successfully fabricated via solvothermal and chemical vapor deposition methods. The WS2/Co9S8 heterostructure has the ability to generate an internal electric field that acts as a powerful driving factor for charge transport. The NC layer and three-dimensional NPG foam provide a special structure for the stabilization of WS2 nanosheets and Co9S8 nanoparticles, which not only increases its conductivity and expands the layer spacing, but also mitigates structural changes in electrode materials during charge and discharge. When NPG@WS2/Co9S8@NC is treated as the anode in a lithium-ion battery (LIB), a capacity of 952 mA h g(-1) at 1 A g(-1) can be achieved even after 600 cycles. The combined effect of self-supported electrodes and heterostructures has given us some new opportunities for improving the capability of anode components in LIBs.

Vanadium oxide is provided with abundant redox centers for high theoretical capacity as anode of sodiumion batteries (SIBs), but still has poor inherent conductivity and volume expansion leading to fast capacity decay during cycling. In the study, the manganese vanadate microspheres enclosed in nitrogen-doped carbon layers (MnV2O4 @NC) are availably constructed via reflux vanadization of Mn glycerol precursor and in situ thermal decomposition. The MnV2O4 @NC microspheres shows excellent the long-cycle stability as anode materials for SIBs, remaining the specific capacity of 205 mAh g-1 at current of 1000 mA g-1 after nearly 4000 cycles. Due to the increased valence range of bimetallic oxides and three-dimensional channels of spinel structure, the cubic MnV2O4 encapsulated by carbon shell can effectively enhance charge transfer, optimize electronic structure, stabilize crystal structure, and improve cycle stability. These results disclose the prospects of vanadate-based spinel material in high performance SIBs. (c) 2023 Published by Elsevier B.V.

To reduce environmental pollution and plastic recycling costs, polyamide-66 (PA-66) as the most consumed engineering polymer needs to be recycled effectively. However, the existing recycling methods cannot convert waste PA-66 into valuable chemicals for upcycling under ambient conditions. Here, we report an integrated hydrolysis and electrocatalytic process to upcycle waste PA-66 into valuable adiponitrile (ADN), adipic acid, and H-2 commodities, thereby closing the PA-66 loop. To enable electrooxidation of the PA-66 hydrosylate hexamethylenediamine (HMD), we fabricated anode catalysts with hierarchical Ni3S2@Fe2O3 core-shell heterostructures comprising spindle-shaped Ni3S2 cores and Fe2O3 nanosheet shells. The unique core-shell architecture and synergy of the Ni3S2 and Fe2O3 catalysts enabled the selective dehydrogenation of C-N bonds from HMD to nitrile C equivalent to N bonds, forming ADN with near-unity Faradaic efficiency at 1.40 V during the 100-h stability test even at 100 mA cm(-2). X-ray photoelectron spectroscopy revealed that the Ni(Fe) oxy(hydroxide) species formed were in the active state during oxidation, accelerating the activation of the amino C-N bond for dehydrogenation directly into the C equivalent to N bonds.