A bottleneck for commercializing sodium-ion batteries is the inadequate plateau capacity of hard carbon anodes, which stems from a deficiency of closed pores. Informed by the "adsorption-insertion-pore filling" mechanism, this work employs a synergistic phosphoric acid activation and pre-oxidation process to construct hard carbon from anthracite with copious closed pores. Consequently, the reversible capacity of the modified hard carbon anode increases by 66.3% to 334.8 mAh g(-1), with its ICE remaining at 90.8%, which is attributed to the critical role of closed pores in facilitating Na+ transport and storage. Extensive investigations demonstrate that the enhanced plateau capacity (257.0 mAh g(-1)) exhibits a strong correlation with the micropore volume of the precursor, validating that the plateau capacity primarily relies on a pore-filling mechanism. The universality of this pore-formation strategy is further demonstrated by extending it to phenolic resin. The modified resin-derived hard carbon achieves a reversible capacity of 415.7 mAh g(-1), representing a 20.1% enhancement, along with a plateau capacity of 337.2 mAh g(-1). Our work not only underscores the pivotal role of precursor cross-linking but also highlights the broad application potential of this pore-formation strategy.

Dual-atom catalysts (DACs) provide a powerful platform for oxygen electrocatalysis, yet rational design remains limited by the lack of transferable mechanistic principles. Machine learning (ML) has the potential to address this gap, yet its role in mechanistic discovery remains largely underexplored despite its wide use in catalyst screening. Here, using extended phthalocyanines (M1M2-ePc), we establish an integrated DFT-ML-experiment framework that maps catalytic performance onto an interpretable electronic landscape. Screening 81 DFT-computed and 360 ML-predicted metal pairs identifies FeM-ePc as a promising bifunctional catalyst family. Notably, SHapley Additive exPlanations (SHAP) analysis highlights the importance of electronic background and the key role of the secondary metal in regulating catalytic activity. First-principles calculations further uncover a cooperative dual-descriptor mechanism, in which d-band center and charge transfer jointly govern bifunctional activity. Combining LASSO with SISSO yields compact analytical formulas that quantitatively reproduce ηORR and ηOER, providing interpretable descriptors for DACs. Guided by these findings, FeCo-ePc-L with atomically dispersed Fe-Co sites was synthesized to experimentally examine the ML-guided prediction. This work highlights the utility of interpretable ML for mechanistic discovery in DACs by revealing role-asymmetric electronic cooperation between paired metal centers.

Cobalt-free lithium-rich layered oxides (Co-free LLOs) represent promising high-capacity and cost-effective cathode chemistries for next-generation lithium-ion batteries. However, their practical application is still limited by sluggish interfacial kinetics and complex redox regulation in the absence of cobalt, which hinders the efficient activation of the Li-rich layered framework and bulk charge transport, resulting in unsatisfactory initial capacity utilization and rate capability. Here, we demonstrate that these intrinsic limitations can be effectively addressed through a spatially decoupled redox strategy in which distinct redox functionalities are assigned to different regions within a single particle. Specifically, a three-region functional architecture is constructed in Co-free LLOs: the bulk region preserves the original layered framework and maintains reversible oxygen redox contribution as the primary source of high capacity; the near-surface bulk region undergoes fluorine substitutional regulation, which effectively modulates oxygen redox behavior by suppressing irreversible oxygen overoxidation while enhancing transition-metal cationic redox to maintain charge compensation; meanwhile, a localized spinel-like reconstructed region formed in the near-surface area provides additional low-voltage capacity through Mn3+/Mn4+ redox and accelerates interfacial Li+ transport via three-dimensional diffusion pathways. The outermost surface is further protected by an in situ formed LiF-rich amorphous layer, which stabilizes the electrode/electrolyte interface. This spatially graded architecture, enabled by fluorine-induced local electronic structure modulation, creates distinct functionalities across different length scales. As a result, the optimized cathode delivers a high reversible capacity of 310.11 mAh g-1, an initial Coulombic efficiency of 87.7%, and a superior rate capability. This work provides a spatially decoupled redox design strategy for developing high-energy cobalt-free cathodes and offers insights into multiscale functional regulation in Li-rich layered oxides.

The green and efficient regeneration of spent lithium iron phosphate (S-LFP) is crucial for the sustainable development of lithium-ion batteries. While the well-preserved olivine structure of spent S-LFP provides a foundation for direct regeneration, its intrinsically low lithium-ion diffusion coefficient poses a kinetic challenge for efficient relithiation. Conventional regeneration methods rely on harsh conditions to accelerate the diffusion of lithium ions into the lithium vacancies of the S-LFP crystal lattice. To address this challenge, this study proposes a "defect-accelerated regeneration" strategy, which achieves efficient repair of S-LFP by performing ball milling in a solution system containing lithium acetate (LiOAc) and citric acid (CA), followed by short-term annealing. The mechanochemical effects induced by this process enable simultaneous lithium replenishment and the controlled introduction of crystal defects, which act as preferential pathways for lithium-ion migration and synergistically enhance the reaction kinetics. Results demonstrate that the regenerated lithium iron phosphate exhibits a complete crystal structure and improved electrochemical performance: a specific discharge capacity of 154.14 mAh g-1 at 0.1C and a capacity retention rate of 93.14% after 500 cycles at 1C, higher than those of the original S-LFP. This work demonstrates a pathway for the low-cost and low-energy consumption recycling of S-LFP.

Improving the interfacial mass transfer efficiencies of ozone and pollutants in heterogeneous catalytic ozonation systems is crucial to solving the technical barrier of low reactive oxygen species (ROS) yield, thereby minimizing interference from coexisting components in water to achieve efficient decontamination. Herein, a biochar-coupled manganese oxide catalyst (MnO@BC) was designed, which achieved a dual adsorption and interfacial reaction between ozone and pollutants, significantly enhanced the hydroxyl radical (·OH) yield, leading to a 92.5% removal efficiency for atrazine (ATZ). The hydroxyl groups on the carbon layer achieve effective adsorption of ozone molecules (Eads=-0.72 eV), inducing Mn-O bond formation with Mn sites and the transfer of 0.29 e⁻, leading to the generation of surface atomic oxygen (*O). Subsequently, this *O spontaneously converts into ·OH, as evidenced by the highly negative Gibbs free energy change (ΔG = -13.9 eV). The improved synergetic process significantly increases ·OH yield by 3.8 times compared to ozone alone. Benefiting from the dual synergy process, the constructed O3/MnO@BC system significantly resists the interference of coexisting components in water, exhibiting unique advantages compared to traditional catalytic systems. It also performed well in purifying broad-spectrum micropollutants, synchronously weakening the toxicity, and blooming superior prospects for filtered water purification. The study designs catalysts from the perspective of the microscopic heterogeneous interface, providing novel theoretical insights and solutions to solve the technical barrier of heterogeneous catalytic ozonation.

Fe-N-C catalysts, especially FeN4 moieties, hold great promise for boosting the oxygen reduction reaction (ORR). However, they still suffer from sluggish reaction kinetics due to the unsatisfactory adsorption energy of intermediates resulting from the symmetrical distribution of electrons in FeN4 active sites. Strategies in single-atom catalysis have primarily focused on tailoring the local coordination of metal centers. Here, we advance this approach by demonstrating that the intrinsic properties of the support can be harnessed as active, cooperative components. We report a symmetry-broken O-Fe-N3 moiety anchored on a hierarchical porous carbon sphere with a negatively charged surface. This "smart" carrier establishes an interfacial electric field that facilitates O2 activation and electrostatically repels harmful intermediates (e.g., H2O2), concurrently enhancing activity and stability. Theoretical calculations also reveal that the resultant structure can trigger energy level splitting of Fe 3d orbitals, thereby regulating the hybridization of the central Fe 3d orbital. Combined with the optimized electronic structure of the Fe site, the catalyst achieves an exceptional half-wave potential of 0.90 V vs. RHE and remarkable durability. A flexible Zn-air battery using this catalyst delivers a high-power density of 249 mW cm-2. This work establishes a new "active site-smart carrier" synergistic design principle, opening a distinct avenue for next-generation electrocatalysts.

Dual-atom catalysts (DACs) outperform single-atom catalysts (SACs) via interatomic electronic modulation of active sites, yet accurate fabrication of diatomic structures restricts their mechanistic research. Herein, we fabricate a Fe-Fe homonuclear DAC (Fe(CN)6-Fe-NC) through strong coordination between ferrocyanide and unsaturated Fe sites on Fe-ZIF-NC inspired by Prussian blue chemistry. A two-step synthetic route preloads Fe ions in ZIF-8 before introducing ferrocyanide, which precisely forms Fe-Fe dual sites and avoids Fe cluster aggregation. The paired Fe atoms deliver two synergistic effects toward the oxygen reduction reaction (ORR): bridging O2 adsorption weakens O─O bonds to reduce dissociation barriers, and intermetallic electron tuning optimizes intermediate desorption. The catalyst achieves a remarkable half-wave potential of 0.91 V, surpassing commercial Pt/C (0.84 V). Assembled as air cathodes, liquid and flexible Zn-air batteries reach peak power densities of 235.9 and 163 mW cm-2 both exceeding Pt/C counterparts. This coordination engineering strategy enables controllable homonuclear diatomic construction and reveals promising prospects of DACs for advanced energy devices.

The commercialization of sodium-ion batteries is significantly hindered by the limited plateau capacity of hard carbon, caused by insufficient closed pores within the carbon matrix. Herein, we employ palm kernel shells as a representative precursor to synthesize closed-pore-rich hard carbon through elemental regulation and ultramicropore defects engineering. Pre-carbonization followed by acid washing enhances the structural stability of the carbon matrix and prevents excessive graphitization induced by internal impurities. Subsequent alkali activation fabricates abundant ultra-micropore defects within the carbon-based precursor, acting as developmental sites to support the formation of closed pores during carbonization. As the temperature increases, the defects are gradually transformed into initially enclosed pores. These initially enclosed pores restrict the bridging and excessive growth of carbon layers, facilitating the formation of short and thin carbon layers that serve as structural boundaries, thus forming a significant number of closed pores. Ultimately, the optimized hard carbon exhibits excellent rate performance with 219.7 mAh g-1 and cycling stability of 95.4 % after 1000 cycles at 10 C. The assembled full-cell delivers high energy densities of 242.1 Wh kg-1 and 182.6 Wh kg-1 at 25 degrees C and -40 degrees C, respectively. Our study provides a new insight into the preparation of hard carbon with high plateau capacity through the utilization of ultra-micropore defects.

Lithium-sulfur (Li-S) batteries have garnered widespread attention and research due to their high theoretical capacity and energy density. However, their commercialization is hindered by several issues, including low electrical conductivity of the sulfur electrode, the polysulfide shuttle effect, and slow charge-discharge kinetics. Double-atom transition metal phthalocyanines (M2-Pc), which are large conjugated compounds with M2-N12 rings, have potential application value in electrochemical catalysis due to their unique electronic structures and metal coordination properties. Through a five-step screening strategy, the study investigated the catalytic activity of a series of M2-Pc (M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn) towards S8/LiPSs. The results show that Fe2-Pc exhibits the best catalytic activity, attributed to its low Gibbs free energy (0.88 eV) in the rate-limiting step of the discharge reaction and its low decomposition energy barrier (0.72 eV) of Li2S during the charge reaction. Additionally, the integral of crystal orbital Hamiltonian population (ICOHP) can serve as a descriptor

Electrocatalytic semi-hydrogenation of alkynes offers a sustainable pathway for synthesizing functionalized olefins, yet challenges in achieving high selectivity and Faradaic efficiency at low overpotentials remain unresolved. Herein, we report bimetallic PdAu electrocatalysts (PdAu@CC) with low Pd loadings for selective semi-hydrogenation of terminal alkynes through an intermetallic hydrogen spillover pathway. The optimized PdAu@CC catalysts with a Pd molar fraction of 4 % demonstrate exceptional performance in converting acetylene benzene to vinyl benzene, achieving 97.5 % selectivity and 78.2 % Faradaic efficiency at a low potential of-0.17 V vs. RHE, outperforming monometallic Au@CC and Pd@CC. Mechanistic investigations reveal that highly dispersed Pd sites in the Au matrix efficiently dissociate water to generate active H* intermediates. Au sites activate alkynes and promote alkenes desorption, which effectively avoid over-hydrogenation of alkynes. Kinetically favorable Pd-to-Au hydrogen spillover enables selective alkynes-to-alkene hydrogenation, suppressing competitive hydrogen evolution. This work highlights the intermetallic hydrogen spillover as a strategic pathway for designing dual-active-site electrocatalysts with high performance in alkyne semi-hydrogenation. (c) 2025 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

The fundamental challenge of trimetallic single-atoms catalysts stems from the difficulty in supporting the coexistence of different metals with their unique physicochemical features. Here, the trimetallic single-atoms electrocatalyst is constructed as a model system to explore electrocatalytic ORR/OER. The tri-metal (Fe, Co, and Ni) single-atoms loaded on nitrogen-carbon framework exhibits superior ORR/OER kinetics (E-1/2 = 0.927 V, E-j=10 = 1.56 V). The flexible zinc-air batteries generate excellent power density and durability (62 mW cm(-2) and 200 h at 15 degrees C, 291.2 mW cm(-2) and 250 h at room temperature). Density functional calculations confirm that the trimetallic synergy effect outperform mono- and bimetallic effects, yielding adsorption strength close to 0. This paper describes an intuitionistic descriptor where Delta E-OH* displays a volcano relationship with ORR overpotential, and establishes a generalized strategy for efficient bifunctional oxygen electrocatalyst while comprehensively understanding the structure-mechanism-activity relationship.

The metal-nitrogen-carbon (M-N-C)-based catalysts are promising to replace PGM (platinum group metal) to accelerate oxygen reduction reaction due to their excellent electrocatalytic performance. However, the inferior intrinsic activity and poor active site density confining further improvement in their performance. Modulating the electronic structure and reasonably designing the pore structure are widely acknowledged effective strategies to boost the activity of the M-N-C catalysts. However, it is a great challenge to form abundant pores to regulate the electronic structure via the facile method. Herein, a hierarchical, porous dual-atom catalyst FeNi-NPC-1000 has been architectured by the Na2CO3 template method and bimetallic doping modification strategy. Benefitting from the optimized pore and electronic structure, the as-prepared FeNi-NPC-1000 possesses a high specific surface area (1412.8 m(2) g(-1)) and improved ORR activity (E-1/2 = 0.877 V vs RHE), which is superior to that of Pt/C (E-1/2 = 0.867 V vs RHE). With the evidence of AC-STEM, XAS, and DFT, the FeNi-N-8-C moiety is proven to be the key active site to realize high-efficiency ORR catalysis. When assembled it as an air cathode of ZABs, FeNi-NPC-1000 displays superior discharge performance (P-max = 367.1 mW cm(-2)) and a stable battery long-life. This article will provide a new strategy for designing dual-metal atomic catalysts applied in metal-air batteries. [GRAPHICS] .

The design and synthesis of low-cost and efficient non-noble metal bifunctional electrocatalysts for enhancing the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is a pressing demand for the development of rechargeable zinc-air batteries. In this paper, a range of metal@nitrogen-doped carbon nanotubes (M@N-CNTs, M = Fe, Ni) materials were prepared by the typical solvothermal synthesis with Fe and Ni co-doped zeolitic imidazolate framework-8 (ZIF-8) as precursors. The synthesized catalysts have a multidimensional structure of one-dimensional M-N-doped carbon nanotubes coexisting with carbonized M-N-doped dodecahedra, providing abundant catalytically active sites for oxygen, as well as multidimensional channels for mass diffusion and electron transport, thus exhibiting excellent catalytic activity and stability. The FeNi@N-CNTs-10 electrocatalyst possesses a half-wave potential of E-1/2 = 0.92 V for ORR and E-j=10 = 1.46 V (eta = 230 mV) for OER in 0.1 molL-1 KOH, which is superior to commercial 20 wt% Pt/C+ RuO2 (E-1/2 = 0.82 V, E-j=10 = 1.61 V (eta = 380 mV)). Zinc-air battery loaded with FeNi@N-CNTs-10 presents a power density of 187 mWcm(-2) and smaller voltage gap (1.0 V) than commercial Pt/C + RuO2 for >1600 discharge-charge cycles at 10 mAcm(-2). The outstanding performance is due to the multidimensional structure, high graphitization carbon and complementary effect between FeNi and M-N-x moiety. The design of multidimensional structure with bifunctional active sites could be extended to other metal-air batteries.

M-N-C(M=Fe,Co,Ni,etc.) catalyst owns high catalytic activity in the oxygen catalytic reaction which is the most likely to replace the Pt-based catalysts.But it is still a challenge to further increase the active site density.This article constructs the high-efficiency FeMn-N/S-C-1000 catalyst to realize ORR/OER bifunctional catalysis by hetero-atom,bimetal(Fe,Mn) doped simultaneously strategy.When evaluated it as bi-functional electro-catalysts,FeMn-N/S-C-1000 exhibits excellent catalytic activity(E 1/2 =0.924 V,E j=10 =1.617 V) in alkaline media,outperforms conventional Pt/C,RuO 2 and most non-precious-metal catalysts reported recently,Such outstanding performance is owing to N,S co-coordinated with metal to form multi-types of single atom,dual atom active sites to carry out bi-catalysis.Importantly,nitrite poison test provides the proof that the active sites of FeMn-N/S-C are more than that of single-atom catalysts to promote catalytic reactions directly.To better understand the local structure of Fe and Mn active sites,XAS and DFT were employed to reveal that FeMn-N 5 /S-C site plays the key role during catalysis.Notably,the FeMn-N/S-C-1000 based low-temperature rechargeable flexible Zn-air also exhibits superior discharge performance and extraordinary durability at-40℃.This work will provide a new idea to design diatomic catalysts applied in low-temperature rechargeable batteries.

Manganese dioxide has been significantly utilized in zinc ion batteries (ZIBs). However, in the rechargeable battery system, the manganese dioxide cathode suffers from poor conductivity, volume expansion, and substance dissolution, resulting in low capacity and poor stability. Herein, a 3D frame structure MnO2@CNTs cathode is proposed. In this system, the electrodeposited spherical MnO2 is anchored and interlinked via the in‐situ growth carbon nanotubes (CNTs) onto the carbon cloth. Benefiting the unique 3D frame structure, the MnO2 structure crush problem and the pathway of the electrons and ions are dramatically improved. The optimized MnO2@CNTs cathode demonstrate a high capacity of 256.35 mAh g−1 at 0.1 A g−1 and exceptional cycling stability. Furthermore, in‐situ Raman spectroscopy elucidates the energy storage mechanism of aqueous ZIBs (AZIBs). Moreover, COMSOL finite elements analysis demonstrates that the petal edge‐rich nanostructures of MnO2@CNTs generate a localized high electric field under constant current, accelerating ion/electron transfer. This work explains the rationale for CNTs to improve the properties of MnO2 cathodes, providing a new perspective for the design of high‐performance batteries.

Aqueous zinc-ion batteries (ZIBs) have been considered one of the most promising flexible chemical power sources, because of their affordable cost, absolute security, and lightweight. However, the development of flexible aqueous ZIBs has been hindered by cathode materials due to their unsatisfied capacity, unstable structure, and ambiguous electrochemical energy storage mechanism. To address the above issues, a high-performance manganese cerium -doped dioxide-based core-shell hybrid structure cathode (CS@Ce-MnO2) has been successfully prepared via a facile low-temperature liquid-phase reaction strategy. Benefit from the delicately designed hierarchical carbon spheres core and cerium-doped manganese dioxide nanosheets shell structure, the capacity and stability of CS@Ce-MnO2 based flexible ZIBs has been dramatically improved, and the origin of the improved electrochemical performance and storage mechanism was demonstrated by electrochemical methods and ex-site x-ray diffraction (XRD) and scanning electron microscopy (SEM). The principal reason for the high reversible specific capacity is the plausible Zn2+ and H+coinsertion/extraction, while the porous structure of the carbon spheres contributes to the improved electron conduction and ion transport in the MnO2 matrix. This work provides a new opportunity for high-performance flexible aqueous zinc-ion batteries.

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Lithium-sulfur (Li-S) batteries have attracted considerable attention owing to their extremely high energy densities. However, the application of Li-S batteries has been limited by low sulfur utilization, poor cycle stability, and low rate capability. Accelerating the rapid transformation of polysulfides is an effective approach for addressing these obstacles. In this study, a defect-rich single-atom catalytic material (Fe-N4/DCS) is designed. The abundantly defective environment is favorable for the uniform dispersion and stable existence of single-atom Fe, which not only improves the utilization of single-atom Fe but also efficiently adsorbs polysulfides and catalyzes the rapid transformation of polysulfides. To fully exploit the catalytic activity, catalytic materials are used to modify the routine separator (Fe-N-4/DCS/PP). Density functional theory and in situ Raman spectroscopy are used to demonstrate that Fe-N-4/DCS can effectively inhibit the shuttling of polysulfides and accelerate the redox reaction. Consequently, the Li-S battery with the modified separator achieves an ultralong cycle life (a capacity decay rate of only 0.03% per cycle at a current of 2 C after 800 cycles), and an excellent rate capability (894 mAh g(-1) at 3 C). Even at a high sulfur loading of 5.51 mg cm(-2) at 0.2 C, the reversible areal capacity still reaches 5.4 mAh cm(-2).

Lithium-sulfur (Li-S) batteries are considered promising candidates for next-generation advanced energy storage systems due to their high theoretical capacity, low cost and environmental friendliness. However, the severe shuttle effect and weak redox reaction severely restrict the practical application of Li-S batteries. Herein, a functional catalytic material of tin disulfide on porous carbon spheres (SnS2@CS) is designed as a sulfur host and separator modifier for lithium-sulfur batteries. SnS2@CS with high electrical conductivity, high specific surface area and abundant active sites can not only effectively improve the electrochemical activity but also accelerate the capture/diffusion of polysulfides. Theoretical calculations and in situ Raman also demonstrate that SnS2@CS can efficiently adsorb and catalyse the rapid conversion of polysulfides. Based on these advantages, the SnS2@CS-based Li-S battery delivers an excellent reversible capacity of 868 mAh/g at 0.5C (capacity retention of 96 %), a high rate capability of 852 mAh/g at 2C, and a durable cycle life with an ultralow capacity decay rate of 0.029 % per cycle over 1000 cycles at 2C. This work combines the design of sulfur electrodes and the modification of separators, which provides an idea for practical applications of Li-S batteries in the future.(c) 2022 Elsevier Inc. All rights reserved.