Tandem electrocatalysis offers considerable potential for selectively converting nitrate ions (NO3-) to ammonia (NH3) via electrochemical reduction, yet its practical application is often hampered by sluggish nitrite ions (NO2-) intermediate transfer between spatially separated active sites and mismatched reaction potentials, which together constrain conversion efficiency and limit high Faradaic efficiency (FE) to a narrow operating window. Herein, we report a rationally designed dual-phase Cu-doped Co/CoO (Cu-Co/CoO) heterojunction, featuring spatially distinct yet synergistic active sites and abundant atomic-scale heterointerfaces that enable accelerated tandem catalysis. Mechanistic investigations reveal that the Cu-doped CoO domain predominantly catalyzes the reduction of NO3-to NO2-, which is rapidly transferred across the heterointerface to the Cu-doped Co domain for further hydrogenation to NH3. As a result, the Cu-Co/CoO catalyst achieves a high FE exceeding 85% and sustains high NH3 yields across a broad potential range. Notably, the catalyst achieves a remarkable NH3 yield of 27.3 mmol h-1 mgcat-1 and an NH3 partial current density of 0.58 A cm-2 at-0.8 V (vs. RHE). Integration into a Zn-NO3-battery system further enables simultaneous high-rate NH3 production and power output. This work establishes a viable methodology for engineering high-performance tandem electrocatalysts and offers new insights into interfacial engineering for renewable NH3 synthesis. (c) 2026, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Graphene-supported single-atom catalysts (SACs) are promising noble-metal-free alternatives for the nitrogen reduction reaction (NRR). However, prevailing studies focus almost exclusively on planar graphene supports, overlooking the significant curvature inherent in experimentally relevant structures. To bridge this gap, we employ density functional theory to investigate the impact of graphene curvature on the NRR performance of M-N3X-C SACs (M = 41 types metal elements; X = N, B, C, O, P, S). Through high-throughput computational screening of M-N-4-C SACs across varying curvatures (r = 4, 6, 8, infinity angstrom), we firstly identified highly active candidates (Tc@c6_cave, V@c6_vex, Tc@c8_cave, V@c8_vex, V@cin_flat) for NRR. We also conducted electronic structure analysis to elucidate the enhanced NRR performance of the identified SACs at the electronic level. Furthermore, we explored the synergistic effects of curvature and coordination environment tailored by heteroatom doping on the NRR performance of M-N3X-C, which demonstrates that TcN3P@c8_cave possesses the best activity and selectivity with the limiting potential of -0.30 V. Crucially, our calculations demonstrate that substrate curvature fundamentally alters the metal-dependent trends in NRR activity given specific coordination environment. This work establishes curvature as a critical design parameter for optimizing SAC with various coordination environments towards efficient NRR catalysis.

Dendritic growth resulting from inhomogeneous magnesium plating and stripping compromises anode integrity, critically limiting the achievable energy density of magnesium metal batteries. Addressing this challenge requires controlling the spatial uniformity of nucleation site distribution, magnesium ion flux, and interfaces. Herein, a scalable surface architecture is engineered on magnesium foil, forming a conformal nanosheet network that minimizes spatial inconsistencies to ensure uniform nucleation and deposition of magnesium metal. The confinement index is introduced to quantitatively describe the network's stability to regulate magnesium ion deposition. The optimized magnesium anode exhibited exceptional stability, achieving over 500 h of reversible plating/stripping under harsh conditions. After 5 days of air exposure, the optimized magnesium anode maintains cycling performance with no degradation, highlighting its outstanding resistance to atmospheric oxidation. Paired with a high mass loading of 17.4 mg cm-2 Mo6S8, full cells demonstrate remarkable cycling stability throughout 3000 cycles. Moreover, large-sized pouch cells incorporating optimized magnesium anodes demonstrate stable cycling performance over 600 cycles when paired with a high mass loading Mo6S8 cathode, while achieving a high energy density of 143.74 Wh kg-1 in combination with a Cu2-xSe cathode. These results substantiate the practical applicability and technological promise of an optimized magnesium anode in advanced battery systems.

A deep understanding of reactant adsorption behaviors is crucial for unraveling structure-activity relationships and identifying simple descriptors for the kinetics of multi-electron redox reactions, such as the sulfur redox process in Li-S batteries (LSBs). Recently, the "10-electron rule" for evaluating the adsorption strength of single atoms (Eads) has been established for free-atom-like single-atom alloys (SAAs). However, our density-functional theory calculations show that this rule is unfeasible for single-atom catalysts (SACs) with metal centers covalently coordinated by nonmetal atoms. Herein, we proposed a new 18-electron rule for covalent SACs by establishing the quasi-atom interaction model (Q-AIM), which interprets the U-type behavior of Eads(S) dominated by antibonding-orbital filling. Additional calculations demonstrate that Eads(S) can serve as an efficient descriptor of the kinetics of sulfur redox involving multiatom polysulfides. Then, guided by the efficient predictor and Q-AIM, we employed machine learning to screen ∼800,000 candidate SACs. Ultimately, we obtained over 400 and 8000 promising SACs for sulfur evolution and sulfur reduction, respectively. Furthermore, Eads(S) can be extended to predict the catalytic performance of SACs in Li/Na/K-S/Se batteries. This work not only simplifies complex multi-electron processes to single-atom adsorption energy but also establishes a link between occupied electronic states and the catalytic performance of SACs.

ABSTRACT Sodium‐metal batteries (SMBs) are gradually emerging as a powerful supplement to lithium‐ion batteries (LIBs) due to their prominent advantages in resources, cost, performance, and other aspects. However, their practical implementation is hindered by the unstable solid electrolyte interphase (SEI). This interfacial issue triggers dendrite growth and electrolyte consumption, resulting in shortened cycle life and low coulombic efficiency of the batteries. This study proposes a highly efficient strategy: incorporating a solvent‐coordinating additive‐tetramethoxygermane (Ge(OCH 3 ) 4 ) into the conventional electrolyte. This additive weakens the coordination ability between sodium ions (Na + ) and solvents, thereby accelerating Na + transport kinetics. Simultaneously, it enables the in situ formation of a germanium/germanium oxide (Ge/GeO 2 )‐containing SEI layer on the sodium (Na) metal surface, which in turn reduces the nucleation energy barrier of Na metal. This dual functionality facilitates the uniform nucleation and deposition of Na + . As a result, the Na||Na symmetric cell cycles stably over 3500 cycles at a high current density of 10 mA cm −2 . Furthermore, the Na 3 V 2 (PO 4 ) 3 (NVP)||Na full cell achieves ultra‐high‐rate performance up to 100 C and demonstrated stable cycling for 4400 cycles at 20 C, with a capacity retention of 93.3%. This work provides an effective approach for the design of advanced SMB electrolyte systems.

Lithium metal batteries (LMBs) represent one of the most promising energy storage systems due to unparalleled energy density. However, in commercial electrolytes, their practical high-power performance is still hampered by unstable electrolyte interfaces, leading to severe anode dendrite growth and cathode degradation. Here, 4-fluoro-3-nitrophenylboronic acid is introduced as a dual-function additive, contributing to uniform N-/F-rich interphase layers at both electrodes of the LMBs. Therefore, in the optimized electrolyte, Li-metal electrodes demonstrate enhanced plating/stripping reversibility of > 700 h (vs. 250 h at 1 mA cm−2 and 0.5 mAh cm−2) and coulombic efficiency of 98.2

Earth-abundant nickel phosphide electrocatalysts show great potential for the hydrogen evolution reaction (HER), yet their efficiency requires further enhancement for practical applications. Herein, a novel in situ strategy is developed to synthesize a high-performance electrocatalyst on nickel foam (NF), composed of N-doped carbon-coated Ni5P4–Ni3P heterostructures. This is achieved through the phosphidation and subsequent carbon coating of hydrothermally grown Ni(OH)2 nanosheets. The resulting catalyst exhibits excellent HER activity in acidic media, requiring a low overpotential of only 63 mV to achieve a current density of 10 mA cm−2. The superior performance stems from the synergistic effects of multiple factors: the porous nanosheet architecture and multi-phase interfaces provide abundant active sites, while the conductive N-doped carbon network significantly enhances charge-transfer kinetics and catalyst stability. This work presents an effective approach for designing efficient non-precious metal HER electrocatalysts.

Abstract The initially anode-free sodium metal batteries represent promising candidates for high specific energy and safe battery systems, relying solely on cathodic sodium reservoirs. However, the irreversible accumulation of electrochemically inactive “dead” Na and unstable solid electrolyte interphases fundamentally constrains cyclability through rapid active Na depletion. Here, we utilize a grain-boundary gallium-rich polycrystalline aluminum current collector to trigger controlled dissolution of aluminum ions. The dissolved aluminum ions modify the local coordination environment of the electrolyte, thereby perturbing the solvation equilibrium of sodium ions and facilitating sodium ions migration toward the positive electrode for charge compensation. The gallium-rich aluminum current collector enables stable Na plating/stripping for over 2500 cycles. The pouch cell with Na 3 V 2 (PO 4 ) 3 delivers 88.7% capacity retention after 100 cycles at 35.1 mA g −1 in 1 M NaPF 6 in diglyme, based on a nominal capacity of 117 mAh g −1 . In addition, the full cell with a high positive electrode loading (47.4 mg cm −2 ) achieves a high specific energy of 201.5 Wh kg −1 , calculated based on all cell components (positive electrode, negative electrode, separator and electrolyte). This work proposes a viable current collector design concept that can be extended to other initially anode-free battery systems.

Aqueous zinc-ion batteries are plagued by anode challenges such as dendrite growth and corrosion, which stem from intrinsic surface heterogeneity. Although constructing a homogeneous interfacial layer is a promising strategy, conventional electrolyte additives often suffer from incomplete or unstable coverage. Here, we evaluated thiol-containing 2-mercaptopyridine (MP) as a potential additive because of its strong coordination capability. However, it unexpectedly exacerbated localized dendrite formation, revealing strong yet uneven adsorption. Enlightened by this, we constructed a uniform MP-based molecular monolayer through a tailored solution immersion process, thereby converting a detrimental effect into a superior protective function. This engineered interface, anchored through dual active sites (thiol and pyridine nitrogen), enables ultrafast and homogeneous zinc adsorption and deposition. Experimental and theoretical results confirm that the monolayer modulates surface charge distribution, suppresses tip-enhanced electric fields, and guides uniform ion flux. Consequently, the symmetric cell achieves exceptional cycling stability of 2100 h at 1 mA cm-2 and 1 mAh cm-2. The Zn||Cu cell cycles stably for over 1100 h with a 99.35% average Coulombic efficiency, whereas full cells show markedly enhanced capacity retention. This work demonstrates a rational interface design by turning an initial failure into a functional strategy.

ABSTRACT Calcium (Ca) metal batteries are challenged by sluggish and unstable Ca plating/stripping in electrolytes with strongly coordinating anions. In the conventional calcium bis(trifluoromethanesulfonyl)imide (Ca(TFSI) 2 )/dimethoxyethane (DME) electrolyte, the large barriers to shed coordinated TFSI – and traverse the CaF 2 ‐rich interphases lead to a plating overpotential exceeding 1.5 V at 0.02 mA cm −2 . In contrast, this work demonstrates that synergistic tris(trimethylsilyl)borate (TMSB) and 2‐methoxyethylamine (MOEA) co‐solvents effectively weaken Ca 2+ –TFSI − coordination by Lewis acid–base interactions and strong bidentate coordination of MOEA with Ca 2+ , while promoting the formation of Ca 2 Si‐rich, kinetically favorable interphases via electron‐rich Si sites. Consequently, the optimized electrolyte enables substantially improved Ca metal redox kinetics and cycling stability, delivering an initial plating overpotential of 0.3 V and stable plating/stripping for over 350 h at 0.02 mA cm −2 with slight potential drift. It also exhibits good rate capability over 0.02–0.2 mA cm −2 , maintaining overpotentials below 0.8 V. This work highlights the crucial role of multi‐solvent synergy in optimizing interfacial stability and redox kinetics for calcium‐metal anodes.

Calcium fluoroborate salt electrolytes are promising for high-voltage Ca-metal batteries (CMBs), yet challenged by poor Ca-metal reversibility at room temperature, urgently necessitating formulation innovation. Here, a qualitative descriptor space is established, strongly correlating solvent dipole effect with Ca-metal reversibility in calcium fluoroborate salt electrolytes. It deduces the desirable solvents for better Ca-metal reversibility are of stronger local and proper overall dipole effects due to a higher degree of salt dissociation and more favorable desolvation and interphase kinetics. Under this guidance, the designed ester-based pure calcium fluoroborate electrolyte demonstrated unparalleled Ca-metal reversibility with initial Ca plating/stripping overpotentials <0.16 V (vs Ca/Ca2+) stably cycling >500 h at 0.02 mA cm(-2) and 0.02 mAh cm(-2), and full cell capacity retention of 84.5% after 120 cycles at 50 mA g(-1) and 1-4.2 V. This work indicates the feasibility of regulating solvent dipole effect to enhance the performance of high-voltage CMBs.

Fe-N-C catalysts are among the most promising platinum-group-metal-free electrocatalysts for the oxygen reduction reaction (ORR), yet their practical application is limited by the insufficient intrinsic activity of isolated Fe sites and Fe-induced degradation. Herein, a neighboring Fe-Cr dual-atom catalyst (FeCr/N-P-C) is constructed via a one-step pyrolysis strategy. Structural characterizations reveal atomically dispersed neighboring Fe-Cr dual sites with a proposed axial N-Fe1N3-Cr1N3 coordination configuration and strong interatomic electronic coupling. Benefiting from Cr-induced electronic modulation, the Fe sites exhibit a 4.6-fold higher turnover frequency (0.534 s− 1 at 0.80 V) than Fe single atoms, together with an onset potential of 1.01 V. The catalyst also shows an ultralow half-wave potential loss of only 21 mV after 30,000 cycles and retains 85

Mn-based Prussian blue (MnHCF) holds promise as one of the cathode materials for aqueous sodium-ion batteries (ASIBs), yet its performance is significantly compromised by unstable Mn3+. Beyond its known role in degrading crystal structure, the impacts on electrolytes have been hardly noticed, which could also initiate side reaction and affect MnHCF. This study targets the research gap and deepen understanding of the degrade mechanism of MnHCF. Here, we reveal that Mn3+ initiates a series of chain reactions unique to MnHCF: Mn3+ undergoes disproportionation and promotes H2O decomposition, generating H+ and MnO2. The accumulated H+ then drove the subsequent steps, dissolving the formed MnO2, attacking the MnHCF framework and finally promoting the self-decomposition of Fe(CN)64-/3-into Fe-based Prussian blue. Realizing the H+ is the indispensable mediator in the chain reactions, we manage to disrupt the reaction pathway using a co-solvent electrolyte with reduced water activity. As a result, the subsequent degradation is effectively suppressed, enabling a full cell with significantly enhanced cycling stability of over 2000 cycles. The study unravels the chain reactions caused by Mn3+ and H+, offering deep insights into the capacity decay mechanisms of MnHCF, expecting to advance the development of durable, reliable ASIBs.

Sulfur-doped graphene (SG) has attracted considerable interest for energy conversion and storage applications. However, the relevant catalytic mechanisms remain obscure due to ongoing contentious debates regarding the location of dopant atoms. While theoretical studies often assume sulfur dopants preferentially reside at edge sites, experimental evidence consistently shows their homogeneous distribution throughout the carbon lattice. Here, we first demonstrated the thermal and dynamical instabilities of previously proposed models of S-bearing defects in the basal plane of SG, which were used to explain experimentally observed enhanced lithium adsorption and magnetism. We then presented new stable defect configurations in the graphene lattice that incorporate both sulfur dopants and inevitable oxygen-bearing functional groups, thereby explaining those experimental observations. These in-plane defect models provide an internally consistent explanation for the active sites and catalytic mechanisms of oxygen, nitrogen, and sulfur reduction reactions, and suggest that the catalytic performance of SG cannot be rationalized solely by edge-located sulfur dopants. In particular, several of the newly identified in-plane defects exhibit calculated activities comparable to, or in some cases exceeding, those of representative edge configurations. Our findings highlight a previously underappreciated role of basal-plane defects in sulfur-doped carbonaceous materials, encompassing both metal-free catalysts and graphene-based single-atom systems.

Amid intensifying global climate change, there is an urgent demand for effective strategies to capture CO2 and convert it into value-added chemicals. Graphdiyne (GDY), with its high surface area, superior conductivity, tunable electronic structure, and robust stability, significantly enhances catalytic activity and selectivity. However, how the electronic structure governs stability, interaction mechanisms and selectivity is still unknown. In this paper, the electronic structure governing catalytic CO2 capture/hydrogenation was investigated for single-atom transition metal catalysts (Ni, Fe, Mo, Ru) anchored on GDY (TM@GDY). First-principles calculations not only unveil the distinct roles of metal centers in modulating adsorption energetics and charge transfer, thereby establishing a structure-activity framework, but also confirm that all TM@GDY systems possess robust electronic configurations. Notably, Ni@GDY primarily relies on van der Waals interactions for CO2 adsorption, while other TM@GDY systems (Fe, Mo, Ru) enable chemical adsorption. Among these, Ru@GDY demonstrates the highest catalytic activity, featuring a strong CO2 adsorption energy (-0.82 eV) and efficient pathways for methane (CH4) and methanol (CH3OH) generation. Mechanistic analysis indicates that the *CO2 -> *HCO route is kinetically favorable, with the intermediate *COOH exhibiting a higher formation probability than *HCO2. The elevated d-band center of Ru synergistically facilitates CO2 activation by weakening the C--O bond strength, stabilizing critical reaction intermediates, and optimizing the reaction energy barriers, thereby enhancing the overall reduction efficiency. These findings advance the fundamental understanding of single-atom catalysts and provide a rational framework for designing high-performance CO2 capture and conversion systems, contributing to sustainable energy solutions.

Sodium manganese hexacyanoferrate (Mn-HCF) is a promising cathode for aqueous sodium-ion batteries (ASIBs) due to its low cost and high theoretical capacity. However, its practical application is hindered by rapid capacity fading, which originates from Mn dissolution and the uneven lattice expansion induced by Jahn–Teller distortion and successive phase transitions. While strategies such as lattice doping, surface coating, and electrolyte additives have been explored to mitigate Mn dissolution, they merely delay rather than prevent the process. Moreover, the subsequent degradation reactions remain poorly understood. Herein, we elucidate a degradation chain reaction initiated by Mn dissolution. Dissolved Mn2+ ions catalyze interfacial water oxidation, generating protons that protonate the C≡N ligands of Fe(CN)64−/3−. The subsequent ligand dissociation releases Fe2+/3+, which then react with residual Fe(CN)64− and Na+ to precipitate NaxFe[Fe(CN)6] (Fe-HCF) on the electrode surface, ultimately leading to the lattice collapse of Mn-HCF. As this chain reaction continues, conventional approaches that only slow Mn dissolution are insufficient, and thus, the vacancies must be refilled in real time to halt the process. Accordingly, we introduce iron(III) trifluoromethanesulfonate (Fe(OTf)3) into a concentrated 17.6 m NaClO4 aqueous electrolyte. The Fe3+ ions rapidly occupy Mn vacancies as they form, thereby blocking the chain reaction at its source. A full cell incorporating the stabilized Mn-HCF cathode and a PTCDI (3,4,9,10-perylenetetracarboxylicdiimide) anode retains 80

Achieving high-capacity dendrite-free zinc deposition has been persistently challenged by the trade-off between interfacial stabilization and ion transport. Conventional electrolyte designs improve interfacial stability at the expense of bulk ion mobility, resulting in rapid failure under high-capacity operation. Herein, we present a strategy that uses a viscous glycidyl ether-based additive to suppress bulk ion diffusion while enabling ultrafast surface transport on Zn (002) planes. In situ electrochemical atomic force microscopy captures epitaxial deposition mediated by rapid adatom diffusion and lattice incorporation, effectively decoupling interfacial kinetics from bulk transport limitations. A dual-functional hydrophobic and zincophilic interface, which suppresses both dendrites and hydrogen evolution, is quantitatively confirmed by quartz crystal microbalance and differential electrochemical mass spectrometry. Consequently, Zn||Zn cells achieve 7800-h stability (1.0 mA cm-2, 1.0 mAh cm-2) and a record 1 Ah single-discharge capacity in pouch cells (1.0 mA cm-2, 10 mAh cm-2). Zn||AlVOH full cells deliver a 1.25-Ah capacity (4.2 mAh cm-2) and retain 83.2% of their capacity after 300 cycles at 0.1 A g-1, illustrating a viable route to practical high-energy aqueous zinc batteries.

Achieving both high-voltage tolerance and fast ion conduction in polyether-based electrolytes presents a fundamental challenge. Conventional stabilization approaches enhance oxidative resistance but typically compromise lithium-ion mobility, resulting in severe polarization under high currents. Here, we report a composite quasi-solid-state electrolyte incorporating ester-terminated poly-tetra(ethylene glycol) diacrylate (polyTEGDA) with aluminum ethoxide (Al(EtO)3) nanowire framework. The unsaturated Al centers act as strong Lewis acids, coordinating with C-O-C and C=O groups to redistribute electron density, thereby expanding the electrochemical stability window from 4.2 to 5.1 V and facilitating the formation of a dense inorganic-organic interfacial ion-transport layer. Furthermore, in situ photopolymerization ensures robust lithium metalelectrolyte contact and mitigates interfacial resistance. Using a comprehensive two-dimensional multinuclear NMR framework-including 1H-1H EXSY, 7Li TQMAS, and 7Li CEST-we directly detected the dynamic evolution of Li-O-Al coordination and quantify fast Li+ exchange across the electrode-electrolyte interface. The electrolyte delivers high ionic conductivity (1.13 & times; 10-3 S cm- 1 at 25 degrees C) and excellent electrochemical stability. Critically, Li||LiNi0.6Co0.2Mn0.2O2 full cells exhibit remarkably high-voltage and high-rate stability at 4.8 V and 3 C for over 200 cycles with an average Coulombic efficiency of 99.19%. This coordination strategy bridges molecular-level stability regulation with practical high-power operation, advancing the design of fast-charging lithium metal batteries.

The development of sodium batteries is hindered by dendrite growth and sodium ion loss in conventional anodes under practical operating conditions. We engineer a gradient sodium-tin alloy/sodium bilayer anode through in situ chemical displacement. The upper gradient alloy phase serves as an ion-buffering interlayer that synergistically regulates thermodynamic driving forces and ion-transfer kinetics to achieve dendrite-free morphology. The underlying metallic sodium layer functions as an ion reservoir dynamically compensating for sodium ions to maintain the structural stability of the gradient phase and mitigate the consumption of sodium during long-term cycling. The resulting symmetric cells demonstrate ultralong cyclability exceeding 7000 h at a current density of 3 mA cm-2. Encouragingly, when paired with a high-loading Na3V2(PO4)3 cathode (30 mg cm-2), the full cell cycles stably for nearly 1000 cycles and delivers an unprecedented energy density of 200 Wh kg-1. This work establishes a materials design paradigm to address fundamental challenges in post-lithium battery systems.

Silicon carbide nanowires (SiC NWs) combine the benefits of bulk SiC materials with the properties of low-dimensional nanomaterials. They are known for their excellent mechanical strength and durability, which are critical for their potential applications in high-stress environments and micro-nano functional systems. Here, the mechanical properties and deformation mechanisms of 2H-SiC NWs with rare defects in the [0001] orientation are reported. A series of in situ operational experiments were carried out to evaluate the mechanical behavior and deformation processes of the nanowires, obtaining dynamic images, quantitative force profiles, stress-strain curves and lattice evolution during bending. Experimental results indicate that the maximum bending strain reached 17.7%, and the viscoelastic behavior during the recovery process after fracture was captured. Based on the elastic deformation and brittle fracture behavior of SiC NWs, this is attributed to the presence of the amorphous SiO2 layer encapsulating the surface of the nanowires, which can also enhance their flexibility, enabling their application under higher pressure conditions. These advancements contribute to the further mechanical design of SiC NWs, expand the photonic application scenarios, and promote their application in high-performance electronic devices.