Ionics最新文献

{"title":"Electro-mechanical trade-offs in solid oxide fuel cell flow channels: multi-objective optimization with machine learning-assisted grey wolf optimizer","authors":"Aimen A. Bouaiss,&nbsp;Mohamed Souri Mimoune,&nbsp;Djafar Chabane,&nbsp;Achraf Senoussi,&nbsp;Oussama Bouaiss,&nbsp;Ali Mohammadi,&nbsp;Nadhir Lebaal","doi":"10.1007/s11581-026-07324-2","DOIUrl":"10.1007/s11581-026-07324-2","url":null,"abstract":"<div><p>Optimizing solid oxide fuel cell (SOFC) performance requires balancing competing electro-mechanical demands. This paper presents an integrated framework leveraging artificial neural networks (ANNs) and the multi-objective grey wolf optimizer (MOGWO) to improve flow channel geometry under coupled electro-mechanical constraints. Channel-shaping parameters, including width, height, and inclination angle, were optimized along with the interdependent interconnect rib dimensions. A Sobol sequence-based design of experiments ensures robust surrogate training, enabling rapid simultaneous maximization of power density and minimization of the interconnect von Mises stress and electrolyte failure probability. Optimal trade-off solutions are identified using the TOPSIS method and validated via FEM simulations. The results reveal two dominant design regimes: wide, shallow channels favor power output but increase mechanical risk, whereas taller, narrower channels enhance structural reliability. The proposed framework significantly reduces computational cost compared to direct FEM approaches, offering a practical tool for comparative thermo-mechanical screening of candidate SOFC designs.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"9447 - 9480"},"PeriodicalIF":3.4,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A robust potentiometric sensor for rapid and selective monitoring of indium(III) ions in environmental waters","authors":"Oguz Özbek,&nbsp;Isa Mert Eski,&nbsp;Kıymet Berkil Akar","doi":"10.1007/s11581-026-07339-9","DOIUrl":"10.1007/s11581-026-07339-9","url":null,"abstract":"<div><p>The industrial use of indium has increased significantly in recent years, raising concerns about its release into the environment during production, recycling, and waste disposal processes. Indium and its compounds may accumulate in environmental compartments and have been associated with adverse effects on aquatic organisms as well as potential human health risks, including pulmonary toxicity following occupational exposure. Therefore, the development of rapid, cost-effective, selective, and in situ analytical methods for indium determination is of considerable importance. In this study, a potentiometric In³⁺–selective sensor was fabricated and its analytical performance was evaluated. The developed sensor exhibited good selectivity toward In³⁺ ions over various potentially interfering ions, a Nernstian sensitivity of 20.2 ± 0.82 mV/decade, a wide linear working range of 1.0 × 10^− 2–1.0 × 10^− 6 M, a low detection limit of 4.71 × 10^− 7 M, and a fast response time of 8 s. In addition, the sensor worked effectively over a broad pH range (5.0–10.0) and demonstrated satisfactory repeatability. The sensor was successfully employed as an indicator electrode in the potentiometric titration of In³⁺ ions with ethylenediaminetetraacetic acid (EDTA). Furthermore, its applicability was verified through the analysis of environmental water samples, yielding satisfactory recovery values and demonstrating the potential of the proposed sensor for practical indium(III) determination in environmental samples.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"9505 - 9514"},"PeriodicalIF":3.4,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anion-participating solvation in multi-salt cooperative electrolytes for enhanced low-temperature Li-storage capability","authors":"Bin Zhang,&nbsp;Qing Yin,&nbsp;Shouxun Peng,&nbsp;Zeyu Zhao,&nbsp;Meiyu Shi,&nbsp;Xiwen Li,&nbsp;Zheng Li,&nbsp;Bin Xiao,&nbsp;Xiuquan Gu,&nbsp;Mingjia Zhi,&nbsp;Eugene Chubenko,&nbsp;Vitaly Bondarenko,&nbsp;Hanna Bandarenka,&nbsp;Yanwei Sui","doi":"10.1007/s11581-026-07336-y","DOIUrl":"10.1007/s11581-026-07336-y","url":null,"abstract":"<div><p>Low-temperature operation remains a major challenge because sluggish Li⁺ transport and aggravated polarization severely compromise energy delivery and cyclability. Here we develop a wide-temperature tri-salt electrolyte comprising LiBF₄, LiFSI and LiDFOB in a PC/DME/iBA solvent matrix. With an optimized formulation (0.75 M LiBF₄, 0.2 M LiFSI, 0.05 M LiDFOB, PC : DME : iBA = 25:65:10, v/v/v, T-electrolyte), Li||LiCoO₂ batteries deliver high reversibility, strong rate capability and durable cycling from − 20 to 40 °C. Remarkably, at −20 °C, the optimized electrolyte sustains 143.5 mAh g^− 1 at 0.2 C and preserves 129.7 mAh g^− 1 after 500 cycles, corresponding to ~ 85.5% of the room-temperature capacity, whereas a conventional low-temperature electrolyte rapidly decays to 47.2 mAh g^− 1 over the same cycles. Raman spectroscopy and molecular dynamics (MD) simulations reveal that anions and iBA participation reconstruct the Li⁺ solvation sheath by suppressing PC over-coordination and lowering representative cluster binding energies, thereby reducing the desolvation penalty and promoting anion-derived inorganic-enriched interphases. XPS reveals that the T-electrolyte stabilizes both Solid Electrolyte Interphase (SEI) and Cathode Electrolyte Interphase (CEI) by promoting LiF/LiSO_<i>x</i>F/borate-rich inorganic passivation while suppressing uncontrolled carbonate/ether decomposition, and by forming a self-limited cathode CEI in which ROCO₂Li semicarbonates act as a compliant scaffold to preserve interfacial integrity under cycling at − 20 °C. This work establishes a practical solvation-interphase design strategy for enhanced Li-storage at low temperature.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"9557 - 9574"},"PeriodicalIF":3.4,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heterojunction-driven MoS₂@TiO₂/g-C₃N₄ nanocomposites enabling superior solar energy harvesting and Cr(VI) photoreduction","authors":"N. Hemavathy,&nbsp;M. Sukanya,&nbsp;M. Thirunavukkarasu,&nbsp;Shradha Umathe,&nbsp;Komatigunta Nagaraju,&nbsp;S. Kumaran","doi":"10.1007/s11581-026-07338-w","DOIUrl":"10.1007/s11581-026-07338-w","url":null,"abstract":"<div><p>The MoS₂@TiO₂/g-C₃N₄ nanocomposite was synthesized through an integrated hydrothermal–polymerization technique and evaluated for its bifunctional role in dye-sensitized solar cells (DSSCs) and photocatalytic Cr(VI) reduction. X-ray diffraction results verified the successful construction of a ternary heterostructure, exhibiting well-defined reflections assigned to anatase TiO₂ [(101), (004), (200)], hexagonal MoS₂ [(002), (100)], and the (002) lattice plane of g-C₃N₄ at approximately 27.4°, confirming the coexistence of all phases within the composite. Morphological observations from SEM revealed that nanosized MoS₂/TiO₂ spheres were homogeneously distributed over g-C₃N₄ sheets, resulting in a three-dimensional interconnected network that minimized particle agglomeration and promoted rapid charge migration. When applied as a photoanode in DSSCs, the composite achieved superior photovoltaic efficiency with <i>V</i>_<i>oc</i> = 0.746 ± 0.02 V, <i>J</i>_<i>sc</i> = 17.01 ± 0.01 mA cm⁻², FF = 68.7 ± 0.02, and an overall PCE of 8.8 ± 0.01%, outperforming both pure TiO₂ (5.4 ± 0.03%) and Pt-based electrodes (7.1 ± 0.03%). The photoanode exhibited a significantly longer electron lifetime (54 ms)—about 8–10 times higher than that of TiO₂ (25 ms)—and displayed minimal solution (<i>Rs</i> = 0.86 Ω) and charge-transfer resistance (<i>Rct</i> = 12.3 Ω) compared to pristine TiO₂ (<i>Rs</i> = 1.22 Ω, <i>Rct</i> = 15.6 Ω). Photocatalytic studies further revealed outstanding Cr(VI) reduction efficiencies of 32%, 45%, 66%, and 98% for g-C₃N₄, MoS₂, TiO₂, and the MoS₂@TiO₂/g-C₃N₄ composite, respectively. The enhanced activity is attributed to the synergistic heterojunction architecture that ensures efficient charge separation and extended light utilization, positioning this hybrid as a highly efficient and environmentally sustainable material for solar energy harvesting and pollutant remediation.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"9515 - 9530"},"PeriodicalIF":3.4,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advanced battery state estimation in electric vehicles using graph neural network and evolutionary optimization","authors":"R. Sundaramoorthi,&nbsp;Chitraselvi S","doi":"10.1007/s11581-026-07316-2","DOIUrl":"10.1007/s11581-026-07316-2","url":null,"abstract":"<div><p>The rapid shift to clean energy technologies has propelled the adoption of Electric Vehicles (EVs), necessitating advanced battery state estimation techniques to optimize lithium-ion (Li-ion) battery performance. Traditional estimation approaches struggle to accurately estimate battery states due to the complex and nonlinear nature of Li-ion batteries. This study presents a novel battery state estimation framework for EVs, integrating the Kolmogorov-Arnold Graph Neural Network (KAGN) with the Chaotic Secretary Bird Optimization (CSBO) algorithm to accurately predict the State of Charge (SoC), State of Health (SoH), and State of Temperature (SoT) of Li-ion batteries. The proposed model addresses the nonlinear and dynamic nature of battery behavior using graph-based feature extraction and evolutionary hyperparameter optimization. The KAGN effectively captures complex interdependencies among battery parameters like voltage, current, and temperature, while CSBO enhances convergence, accuracy, and generalization by avoiding local optima and tuning key parameters. The system validates its performance using the NASA Li-ion Battery Dataset and real-time experimental setups, achieves a Mean Absolute Error (MAE) of 0.0065, a Root Mean Square Error (RMSE) of 0.0085, and a high R² score of 0.9885, and outperforms existing Deep Learning (DL) models. Additionally, the architecture incorporates an interleaved dual-phase bidirectional DC-DC converter for efficient energy regulation, power distribution, and thermal stability. Through simulation and experimental validation, the KAGN-CSBO framework demonstrates superior accuracy and robustness in predicting battery states under varying operational conditions, enhancing battery safety, lifespan, and energy efficiency.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"9481 - 9503"},"PeriodicalIF":3.4,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring Li + and Na+ substitution for defect engineering in high-entropy oxides for lithium storage behavior","authors":"Ersu Lökçü","doi":"10.1007/s11581-026-07301-9","DOIUrl":"10.1007/s11581-026-07301-9","url":null,"abstract":"<div><p>High-entropy oxides (HEOs) are promising electrode materials for electrochemical energy storage due to their structural tunability and defect driven functionalities. Here, aliovalent substitution of Li⁺ and Na⁺ into rock-salt (MgCoNiCuZn)O is investigated. Single-phase HEOs with 15 mol% aliovalent incorporation were synthesized and confirmed by XRD and Rietveld refinement. XPS analysis revealed higher oxygen vacancy concentrations in Na-containing samples compared to Li-containing ones. Both systems exhibited comparable electrochemical behavior with high reversible capacities, while Na⁺ containing HEOs demonstrated slightly better rate capability and cycling stability. These results highlight that Na, owing to its abundance and low cost, can serve as a sustainable alternative to Li for defect engineering and performance optimization in HEO-based anodes. This study also opens new opportunities for designing HEO-based anodes and extending these concepts to other functional HEOs through compositional engineering.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"9547 - 9556"},"PeriodicalIF":3.4,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11581-026-07301-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Production, characterization, and adsorption modeling of Pb(II) ions using eco-friendly pomegranate peel, biochar, and activated carbon","authors":"Nilgün Onursal,&nbsp;Mutlu Canpolat,&nbsp;Yalçın Altunkaynak","doi":"10.1007/s11581-026-07340-2","DOIUrl":"10.1007/s11581-026-07340-2","url":null,"abstract":"<div><p>Pomegranate peel was transformed into three adsorbent materials, including raw pomegranate peel (RPP), biochar produced by pyrolysis (BPP), and activated carbon (PPAC), and comparatively evaluated for Pb²⁺ removal from aqueous solutions. The main objective of this study is to investigate the effect of thermal conversion and chemical activation on the adsorption performance of pomegranate peel-derived materials and to develop a sustainable and high-efficiency biosorbent for heavy metal remediation. PPAC was produced via pyrolysis and subsequent ZnCl2 chemical activation of pomegranate peel biomass. Batch experiments identified optimal conditions at pH 5.31 and 120 min contact time with an initial Pb²⁺ concentration of 250 mg/ L. At 298 K, equilibrium capacities (Q_m) reached 53.19 mg/ g (RPP), 147.05 mg/ g (BPP), and 370.37 mg/ g (PPAC), revealing a pronounced enhancement after thermal conversion and especially after chemical activation. This significant improvement demonstrates the effectiveness of structural and surface modifications in enhancing metal adsorption capacity. The superior performance of PPAC is associated with its highly developed porous framework and enriched surface chemistry, which intensify metal–surface interactions. Adsorption behavior followed the pseudo-second-order kinetic model, indicating that Pb²⁺ uptake is governed primarily by surface-controlled chemical processes. Thermodynamic analysis revealed a spontaneous and endothermic adsorption process, with negative ΔG^o values ranging from − 15.92 to − 20.54 kJ/mol, a positive ΔH^o value of 41.57 kJ/mol, and positive ΔS^o values of 192.92–195.32 J/mol.K. These findings highlight the environmental relevance of converting agricultural waste into efficient adsorbents for sustainable wastewater treatment applications. The findings confirm that activation of pomegranate peel substantially upgrades its adsorption efficiency, highlighting PPAC as a viable material for sustainable Pb²⁺ remediation.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"9405 - 9423"},"PeriodicalIF":3.4,"publicationDate":"2026-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A ternary BiOCOOH/g-C3N5/Carbon nanotube nanocomposite engineered for enhanced pseudocapacitance and energy storage","authors":"Velarasan V,&nbsp;Puviarasu P","doi":"10.1007/s11581-026-07333-1","DOIUrl":"10.1007/s11581-026-07333-1","url":null,"abstract":"<div><p>While bismuth oxyformate (BiOCOOH) is known to be a promising pseudocapacitive material for supercapacitors, its poor electrical conductivity, low surface area and cyclic stability continue to hinder its practical applications. Here we report the first ternary integration of BiOCOOH nanospheres with nitrogen-enriched graphitic carbon nitride (g-C₃N₅) nanosheets and acid-functionalised multi-walled carbon nanotubes (MWCNTs) into a hierarchical nanocomposite via a facile solvothermal method. Three specific innovations distinguish this work: First, the use of g-C₃N₅ (confirmed by X-ray photoelectron spectroscopy (XPS) N 1s analysis) rather than the conventional graphitic carbon nitride (g-C₃N₄) provides a nitrogen-richer, more electrochemically active scaffold. Second, systematic kinetic analysis confirms a mixed pseudocapacitive charge-storage mechanism (b-value = 0.647; surface-capacitive contribution increasing from 43% at 10 mV s^− 1 to 63% at 50 mV s^− 1). Third, the ternary architecture reduces the charge-transfer resistance by more than 90% relative to pure BiOCOOH (from &gt; 22,000 Ω to 1,834 Ω), as confirmed by electrochemical impedance spectroscopy (EIS). The composite delivers a specific capacitance of 419 F g^− 1 at 0.5 A g^− 1 by the linear galvanostatic charge-discharge (GCD) method, a 5.4-fold improvement over bare BiOCOOH and retains 92% capacitance over 1000 cycles. When assembled as a BiOCOOH/g-C₃N₅/MWCNT // activated carbon asymmetric coin-cell device, a specific cell capacitance of 63.3 F g^− 1 at 1 A g^− 1 and a peak energy density of 28.49 Wh kg^− 1 at 900 W kg^− 1 are achieved, with 13.43 Wh kg^− 1 retained at 2250 W kg^− 1. These findings demonstrate the viability of BiOCOOH/g-C₃N₅/MWCNT nanoarchitecture as a promising, cost-effective, and active electrode material for future-generation pseudocapacitive energy storage devices.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"9425 - 9446"},"PeriodicalIF":3.4,"publicationDate":"2026-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-situ Ni-doped W18O49/NF compatible with Al3+ electrolyte for high-rate performance in supercapacitors","authors":"Boya Wang,&nbsp;Junkai Li,&nbsp;Chen Zhu,&nbsp;Jin Hu,&nbsp;Shizhao Xiong,&nbsp;Kaizhao Wang","doi":"10.1007/s11581-026-07328-y","DOIUrl":"10.1007/s11581-026-07328-y","url":null,"abstract":"<div><p>Tungsten oxides with oxygen vacancies, particularly W₁₈O₄₉, hold promise for pseudocapacitive energy storage but are often limited by moderate conductivity and insufficient structural stability under high-rate operation. In this work, a Ni-doped W₁₈O₄₉ electrode with an urchin-like architecture directly grown on nickel foam (Ni-W₁₈O₄₉/NF) is reported via a one-step solvothermal method. This unique interconnected microsphere morphology provides abundant active sites, facilitates electrolyte penetration, and ensures efficient charge transport. The capacitive behaviors of Ni-W₁₈O₄₉/NF electrode in different electrolytes were compared and screened. As a result, when evaluated in 1 M AlCl₃ electrolyte, the electrode delivers a specific capacitance of 625 mF cm^− 2 at a high current density of 20 mA cm^− 2. Moreover, it exhibits a high Coulombic efficiency of 99.76% and excellent capacitance retention of 99.33% after 3000 cycles at 15 mA·cm^− 2. This is confirmed to be attributed to the pseudo-capacitance contribution generated by the smaller Al³⁺ diameter embedded in the Ni-W₁₈O₄₉ lattice. The doped Ni element extends the diameters of these tunnels and generates additional potential defects, thereby providing more sites for the incorporation of Al³⁺. This work provides a scalable design strategy for durable, high-rate supercapacitor electrodes by combining transition-metal doping, oxygen-defect engineering, and electrolyte design.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"9395 - 9404"},"PeriodicalIF":3.4,"publicationDate":"2026-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Towards efficient hydrogen production: A study on ammonia electrolysis technology — catalyst mechanisms and design strategies","authors":"Wanze Li,&nbsp;Kailong Zhang,&nbsp;Xiaofeng Gu,&nbsp;Tianxiang Li,&nbsp;Shihan Chen,&nbsp;Haoran Zhang,&nbsp;Yufang Ye,&nbsp;Hewen Liu","doi":"10.1007/s11581-026-07322-4","DOIUrl":"10.1007/s11581-026-07322-4","url":null,"abstract":"<div><p>Hydrogen energy serves as a pivotal clean energy carrier for deep decarbonization in hard-to-abate sectors; however, its large-scale deployment is impeded by bottlenecks in hydrogen storage and transportation. Ammonia, distinguished by its high hydrogen storage density (17.6 wt%) and favorable logistics, has emerged as an ideal hydrogen storage medium. Electrochemical ammonia oxidation (AOR) enables the efficient conversion of ammonia to hydrogen under mild conditions, offering significant energy savings with a theoretical potential of merely 0.06 V vs. RHE, drastically lower than the 1.23 V required for water electrolysis. This review systematically summarizes recent advancements in this technology, focusing on reaction mechanisms and catalyst design optimization. Regarding the mechanism, we delineate typical ammonia oxidation pathways, such as the O-S and G-M mechanisms, and contrast the reaction steps and intermediates of AOR with those of the oxygen evolution reaction (OER). In terms of catalyst development, we discuss performance optimization via structural regulation and electronic modification. Notably, single-atom anchoring technology is highlighted for maximizing atomic utilization and precisely tuning electronic structures through atomic-level metal dispersion, providing a novel strategy for designing efficient, low-cost catalysts. Finally, we summarize current challenges and outline future directions—ranging from catalyst performance optimization and membrane electrode assembly (MEA) development to system integration and demonstration—aiming to propel this technology toward scalable, cost-effective implementation and bolster the hydrogen economy.</p><p>Trial registration number: Not applicable.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"32 9","pages":"8903 - 8932"},"PeriodicalIF":3.4,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}