Electrolytes play a key role in determining the electrochemical performance, safety, and lifespan of potassium-based batteries, making their selection and optimization a critical area of research. This study systematically investigates the effects of two major potassium-based battery electrolytes, potassium hexafluorophosphate (KPF6) and potassium difluorosulfonimide (KFSI) in ethylene carbonate/diethyl carbonate (EC/DEC) solvents, on battery performance, solid electrolyte interphase (SEI) stability, aluminum (Al) current collector corrosion behavior, electrochemical stability window, and dendrite growth issue. Experimental results reveal that KFSI electrolyte significantly outperforms KPF6 in terms of cycling stability, rate capability, and Coulombic efficiency (CE), primarily due to the formation of a high-quality SEI on electrode surface. Through X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) analyses, we construct the SEI structure for both electrolytes, and find that the SEI formed by KFSI is more uniform and stable. Additionally, KPF6 exhibits weaker corrosivity towards the Al current collector compared to KFSI due to the formation of an AlF3 layer with higher oxidation stability on Al surface. Furthermore, in-situ optical microscopy observations indicate that the dendrite growth in KFSI electrolyte is more uniform, preventing the aggregates. These findings provide essential experimental evidence and theoretical support for optimizing the electrolyte in potassium-based batteries.

ABSTRACT Ru atomic clusters (AC) are promising cost‐effective platinum‐group‐metal anode catalysts for the alkaline hydrogen oxidation reaction (HOR) in anion‐exchange‐membrane fuel cells (AEMFCs), yet their practical application remains limited by insufficient structural robustness and sluggish proton transport across the electrolyte/electrode interface. Herein, we report a design concept that leverages p ‐block indium single atoms with In‐N 3 O 1 coordination as electronic bridges to stabilize Ru AC and reconstruct a proton‐conductive interfacial hydrogen‐bond network for efficient and durable HOR catalysis in practical AEMFCs. We find that the bridged In‐N 3 O 1 sites establish strong covalent Ru‐In anchoring interactions through pronounced d‐p orbital hybridization, stabilizing Ru AC against coalescence and detachment for markedly improved operational durability. Meanwhile, electronic coupling between Ru AC and bridged In‐N 3 O 1 sites tunes surface oxophilicity of Ru to promote higher coverage of hydroxyl adsorbate species and drive dynamic reorientation of interfacial water from cation‐bound states toward free water in the gap region, thereby reinforcing hydrogen‐bond connectivity and enabling more efficient interfacial proton transport. The resulting Ru AC/In 1 @CNO delivers a mass activity of 7.17 A mg Ru −1 , surpassing Pt/C by 9.0‐fold. Particularly, Ru AC/In 1 @CNO‐based AEMFCs achieve a high peak power density of 1.33 W cm −2 and maintain stable operation for over 50 h at 500 mA cm −2 .

Dead-ended proton exchange membrane fuel cells are highly susceptible to liquid-water accumulation, which destabilizes reactant transport, spatial current generation, and long-term operation. In this study, a thermally assisted drainage strategy is proposed to promote in-cell water redistribution through a proposed evaporation-migration-condensation-discharge pathway. Unlike conventional thermal-management approaches that mainly pursue temperature uniformity or overall performance enhancement, this work uses a deliberately imposed local temperature gradient as the direct driving force for thermally assisted drainage. A custom 75 cm2 single-cell platform was developed and integrated with in situ flow visualization, 36-point segmented current-density measurement, electrochemical impedance spectroscopy, and post-test microstructural characterization to evaluate the drainage behavior and effects of this strategy. Under the tested conditions, increasing the bottom-zone temperature from 50 to 80 °C increased the cell voltage at 1.2 A·cm−2 by 5.61%, reduced the cathode flooded-area fraction from 37.69% to 11.86%, and increased the outlet-condensate collection ratio from 21.96% to 55.00% at 0.8 A·cm−2. In addition, the proposed strategy mitigated cathode catalyst-layer thinning and platinum particle coarsening after 120 h of operation. These results indicate that, under the tested single-cell conditions, localized thermal-gradient management can mitigate flooding-induced instability and improve water redistribution in dead-ended proton exchange membrane fuel cells, while providing an experimental basis for evaluating longer purge intervals and more efficient reactant use in future system-level studies.

Symmetric solid oxide cells (SSOCs) have attracted considerable attention because of their simplified architecture and reversible operation, but their advancement is hindered by a scarcity of electrode materials that simultaneously combine high catalytic activity and robust redox stability. Herein, B-site Ru-doped, A-site-deficient (La0.6Sr0.4)0.9Ru0.1Co0.2Fe0.8O3-δ (LSRCF) is developed as a high-performance symmetric electrode. Ru doping combined with A‑site deficiency enables dual functionality. On the fuel electrode side, CoFeRu nanoalloys exsolve in situ to form active metal/oxide heterointerfaces, accelerating fuel oxidation. DFT calculations further reveal that the exsolved CoFeRu/RP-LSRCF heterointerface strengthens propane adsorption, lowers the dehydrogenation barrier, and facilitates oxidation of carbonaceous intermediates, thereby accounting for the excellent coking resistance. On the oxygen electrode side, Ru suppresses detrimental Sr segregation by increasing its migration barrier and improves oxygen reduction kinetics. At 850°C, the LSRCF cell delivers peak power densities of 940, 860, and 1230 mW cm-2 under H2, CH4, and C3H8, respectively, with outstanding tolerance to coking and sulfur. In CO2 electrolysis mode, the cell achieves a current density of 3390 mA cm-2 at 1.6 V and 850°C with stable long-term operation. These results demonstrate an effective strategy for developing high-performance symmetric electrode materials.

Proton exchange membrane fuel cells operating in dead-end mode suffer from spatially coupled water-thermal non-uniformities, which lead to inlet membrane dehydration and outlet flooding, jointly degrading performance and durability. Conventional uniform cooling strategies cannot effectively decouple these competing phenomena, which motivates the development of spatially differentiated thermal management approaches. A multi-zone cooling strategy has been developed to enable independent precision control of three temperature zones (30 degrees C/60 degrees C/80 degrees C) within a single cell. This innovation achieves synergistic water-thermal regulation by actively leveraging thermal gradients: Outlet flooding is suppressed through a localized high-temperature zone (80 degrees C) that enhances liquid water evaporation; Inlet membrane dehydration is prevented via a cooler upper zone (30 degrees C) that promotes water retention; Compared with integral cooling at 60 degrees C, the optimized multi-zone cooling improved current-density uniformity by 45.49%, reduced ohmic resistance by up to 26.12%, and increased cell voltage by 6.86% at 1100 mA & sdot;cm-2, while decreasing electrochemical surface area loss from 38.52% to 7.16% and suppressing the growth of hydrogen crossover by 59.57% over 120 h These results indicate that multi-zone cooling can effectively decouple water-thermal failure modes in dead-end operation and significantly enhance performance stability and durability, highlighting its potential for advanced thermal management in proton exchange membrane fuel cells.

The development of efficient and stable cathode materials for in-situ hydrogen peroxide (H2O2) production via the two-electron oxygen reduction reaction (2e- ORR) is pivotal for advancing electro-Fenton technology. Herein, a monolithic carbon-based cathode (CM-1000) was fabricated through direct carbonization of a thermosetting phenolic resin and employed as an efficient and durable electrode for H2O2 production in electroFenton system. The self-supporting and binder-free architecture effectively eliminates interfacial resistance and catalyst detachment issues commonly associated with catalyst-coated electrodes, thereby ensuring stable catalytic activity and structural integrity. To benchmark its performance against common carbon-based materials, the CM-1000 cathode achieved a H2O2 production rate of 1.82 mmol center dot L- 1 center dot h- 1 under optimal conditions (current 100 mA, pH 3), significantly surpassing conventional graphite bar (0.32 mmol center dot L- 1 center dot h- 1) and carbon felt (1.07 mmol center dot L- 1 center dot h- 1). Such performance stems from a synergistic effect of a highly aromatic carbon matrix enriched with stabilized carbonyl (C = O) and etheric (C-O-C) functional groups, coupled with a well-developed porous architecture (BET surface area 407.52 m2 center dot g- 1). In the electro-Fenton system, CM-1000 achieved complete degradation of dimethyl phthalate (DMP) within 45 min (kapp=0.100 min- 1), while maintaining stable 100% degradation efficiency and consistent H2O2 production performance over seven consecutive cycles. These results demonstrate the great potential of the monolithic carbon-based cathode for practical electro-Fenton water treatment.

Herein, we delved into the mechanism behind the enhanced OER activity of NiMoO4 contributed by amorphous ceria. The in situ generated Ce4+-O-Ni species regulate the electronic structure, facilitate charge transfer and promote hydroxyl adsorption, thereby endowing the NiMoO4@CeOx with exceptional catalytic activity and stability.

Low-temperature solid oxide fuel cells (LT-SOFCs) offer efficient and fuel-flexible energy conversion but require reduced operating temperatures to enable cost-effective and durable deployment. Here, we investigate three LiNiO2-based electrodes N10-1 (LiNiO2), N10-4 (Li0.95NiO2), and Al-doped Ni-9 (10 wt% Al2O3-modified LiNiO2) as anode materials for LT-SOFCs. Structural and vibrational analyses reveal that lithium deficiency induces lattice disorder and phonon softening, while Al substitution regulates local bonding environments. SEM and XPS measurements indicate distinct particle morphologies and surface oxygen chemistries, with Ni-9 exhibiting stabilized Ni3+ states and modified non-lattice oxygen contributions. Electrochemical testing demonstrates that Ni-9 delivers enhanced electrochemical transport behavior and peak power densities (PPDs) of 665 mW cm-2 (H2), 568 mW cm-2 (C3H8), and 388 mW cm-2 (CH4) at 550 degrees C, outperforming N10-1 and N10-4. These results demonstrate that Al2O3-modified LiNiO2-based anodes achieve functional electrochemical stability and fuelflexible performance, providing a promising pathway toward low-temperature SOFC operation.

Efficient and durable catalysts are important for the oxygen evolution reaction (OER) and urea oxidation reaction (UOR) to achieve sustainable hydrogen production. However, the differences in binding energies of different intermediates pose challenges for achieving bifunctional catalysts. Herein, we present an advanced nickel-iron phosphide catalyst enriched with phosphorus vacancies (Vp-NiFeP/NF), which demonstrates an ultra-high activity of 222 mV at 10 mA cm-2 in OER and 1.41 V at 100 mA cm-2 in UOR with long-term stability. In situ Raman spectroscopy confirms that phosphorus vacancies accelerate surface reconstruction from Ni2P to NiOOH, while in situ ATR-SEIRAS reveals that oxyanion suppresses OH- adsorption, thereby enhancing the selectivity of the urea oxidation reaction. Moreover, phosphorus vacancies facilitate the breaking of C-N bond in urea, thus accelerating its decomposition. Density Functional Theory (DFT) research confirmed that vacancies induce localized inhomogeneous spin states of asymmetric nickel sites and simultaneously tune the binding energies of key intermediates in different pathways, thereby improving the catalytic efficiency of OER and UOR. This research provides a new strategy for developing high-performance electrocatalysts for water splitting and urea oxidation.

As an extremely promising process for converting methane (CH4) and carbon dioxide (CO2) to syngas, dry reforming of methane (DRM) has attracted considerable attention due to its wide industrial application. However, the performance of nickel-based catalysts in DRM is seriously restricted by carbon deposition, sintering, and poor long-term stability at high temperatures. Herein, CeO2 nanorods were employed as support for Ni-Co catalysts. The current work not only stabilized the metal phase but also enhanced the CO2 activation by the Ni-Co bimetallic system, therby effectively suppressed carbon deposition and enhancing both the thermal stability and catalytic performance. The 7Ni-Co/CeO2 nanorod catalyst displayed excellent catalytic performance in DRM, which exhibited 91.8% CO2 conversion and 90.2% CH4 conversion at 800 & ring;C, and the H-2/CO ratio was 0.86 with stable conversion for a long time. Meanwhile, it also displayed remarkable long-term stability in DRM. The 7Ni-Co/CeO2 nanorod catalyst still had less than a 1% decrease in conversion after a 450 min reaction, and the carbon deposition was almost ignored. This work reported the first investigation of CeO2 nanorods as support for Ni-Co catalysts, providing an effective approach for efficient and stable DRM in industrial application.

Reversible solid oxide cells (Re-SOCs) are promising devices for efficient energy conversion and CO2 utilization. However, conventional La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) oxygen electrodes suffer from severe Sr surface segregation and CO2 poisoning, which lead to the formation of insulating SrCO3 and rapid performance degradation. Herein, an ordered macroporous LSCF oxygen electrode (LSCF@PMMA) is constructed via a template-assisted strategy to regulate lattice strain and surface stability. The macroporous architecture introduces compressive lattice strain and well-defined mass-transport channels, which enlarge the triple-phase boundaries (TPBs). Structural analyses and detailed theoretical calculations reveal that the strain-enhanced O-2p-M-3d hybridization lowers the energy barriers for oxygen adsorption and dissociation while increasing the Sr migration barrier. Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) and in situ Raman further verify that suppressed Sr segregation effectively enhances CO2 tolerance. As a result, the single-cell with the LSCF@PMMA electrode delivers a peak power density of 1.22 W cm-2 at 850°C in fuel cell (FC) mode and a current density of 3.35 A cm-2 at 1.8 V for CO2 electrolysis, while also exhibiting negligible degradation over 150 h in FC mode and excellent stability during reversible operation. This work highlights strain-engineered as an effective strategy for developing intermediate-temperature CO2-tolerant electrodes in Re-SOCs.

This review highlights the growing importance of electrocatalytic CO 2 reduction in sustainable energy production, focusing on overcoming key industrial challenges, such as catalyst instability, poor selectivity, and low energy efficiency.

Dry reforming of methane, the endothermic co-conversion of CH4 and CO2 into syngas (H2/CO), is typically limited by low-temperature activity and carbon-induced deactivation at high temperatures. Here, a geometrically isolated dual-site architecture is established by co-anchoring Ni and Ru atomic sites on defect-rich CeO2. The optimized 1NiRu/CeO2 catalyst achieves CH4/CO2 conversions of 21.46%/24.10% and a H2/CO ratio of 0.91 at 500°C, and approaches equilibrium (86.77%/92.78%) at 750°C. 1NiRu/CeO2 demonstrates outstanding stability over 150 h, with negligible carbon deposition compared to 1Ru/CeO2. Operando spectroscopy and theoretical calculations reveal preferential CH4 activation at Ru sites in the isolated Ni-Ru dual-site structure. The Ruδ+-Ov-Ce3+ interfacial sites preferentially dissociate CH4 into CH3 * species that are further oxidized to CH3O* via a low-barrier, lattice oxygen-mediated pathway, while Niδ+-Ov-Ce3+ sites readily activate CO2 and replenish Olattice. This oxidative pathway effectively suppresses CHx deep dehydrogenation and, coupled with Ni-driven CO2 activation, establishes a self-sustaining Olattice/Ov redox cycle. This synergistic cycle enables a site-selective division of labour for CH4/CO2 activation, thereby maintaining coke-resistant activity across 400°C-750°C. This work establishes a generalizable strategy for isolated dual-site catalyst design, where Ru-preferential CH4 activation and vacancy-governed interfacial cooperation orchestrate low-temperature activity, stability, and coke resistance, enabling efficient and durable CH4/CO2 valorization via dry reforming.

Local reversal is a hidden failure mode in proton exchange membrane fuel cells, in which abnormal local current may develop before global voltage reversal is detected. This study investigates local reversal induced by membrane drying and its mitigation through targeted hydrothermal regulation. A dual-zone cooling structure was developed to regulate the dehydration-sensitive region independently from the remaining cell region. High-frequency resistance, electrochemical impedance spectroscopy, segmented current–density mapping, scanning electron microscopy and transmission electron microscopy were combined to examine the effects of membrane hydration, gas-feeding direction and local cooling temperature. Low initial membrane hydration caused local reversal by disrupting local proton transport, amplifying ohmic polarization, and forcing current redistribution toward better-hydrated regions. Extending humidified nitrogen conditioning improved membrane hydration and suppressed the reversal region. Gas-feeding direction altered local water distribution, with bottom anode feeding and top cathode feeding giving the most uniform current distribution. Local cooling further mitigated local reversal by improving water retention in the dehydration-sensitive region, and 40 °C provided a balanced trade-off between reversal suppression and electrochemical loss. After 120 h, catalyst-layer thinning decreased from 24.55 % to 11.10 %, while platinum agglomeration decreased from 40.68 % to 21.31 %. These results demonstrate that targeted hydrothermal regulation suppresses the membrane-drying-driven reversal pathway and improves local durability.

Abstract The catalyst Sr 2 Fe 0.5 NiMo 0.43 Ru 0.07 O 6 was prepared by a solid-state method. Upon reduction, Fe-Ni-Ru alloy nanoparticles exsolve and strongly interact with the high-oxygen-vacancy support. This work reveals the stabilization mechanism of the exsolved perovskite structure, offering new insights for the design of efficient and long-life DRM catalysts.

Solid oxide cells (SOCs) are efficient for energy conversion and storage, but operation on hydrocarbons is limited by coking, sulfur poisoning, and slow surface kinetics. To address these challenges, we constructed a 3D oxygen-exchange network that integrates Sr1.9Fe1.5Mo0.43Ru0.07O6-delta (SFMR), exsolved FeRu nanoalloy, and a continuous CeO2 coating using an impregnation-exsolution strategy. Within this oxygen-exchange network, a vacancy-rich ceria/perovskite interface hosts an interfacial dipole (FeRu <-delta(-) | CeO2 ->delta(+)) that couples exsolved FeRu to the Ce4+/Ce3+ redox pair. This dipole-driven charge redistribution enriches FeRu d states at the Fermi level (E-F) and strengthens O 2p-d mixing, providing a unified lever to accelerate C & horbar;H and H & horbar;H bond activation and expedite oxygen delivery, aligning electronic conduction with oxygen-exchange at a single interface. CeO2/SFMR fuel-electrode-based cells deliver peak power densities of 1.89 W cm(-2) in H-2 and 1.63 W cm(-2) in propane at 850 degrees C, stable operation for 250 h in naphtha without coking and for 50 h in 50 ppm H2S-H-2, and 3.95 A cm(-2) at 1.6 V for CO2 electrolysis. These results define an efficient route to coking- and sulfur-tolerant SOC fuel electrodes by pairing a d-state-rich exsolved alloy with a ceria oxygen shuttle in a 3D oxygen-exchange network.

Direct selective conversion of methane under mild conditions remains a challenge. Photocatalytic nonoxidative coupling of methane (NOCM) offers a sustainable route to value-added hydrocarbons and hydrogen yet suffers from intrinsic trade-offs between activity, selectivity, and stability. Here, we report a charge-polarized Pt-Au nanoalloy on TiO2 that enables synergistic C2+ and H-2 production in a continuous-flow photoreactor. The optimized Pt-Au/TiO2 exhibits C2+ and H-2 yield rates of 22.3 +/- 0.1 mu mol h(-1) (1115 +/- 5 mu mol g(-1) h(-1)) and 21.2 +/- 0.1 mu mol h(-1) (1060 +/- 5 mu mol g(-1) h(-1)), respectively, with a C2+ selectivity of 99.0 +/- 0.4% and stability over 210 h under light irradiation. The catalyst delivers an optimal balance of high product yields, near-quantitative C2+ selectivity, and stability under mild conditions, outperforming reported photocatalytic NOCM systems. In situ studies reveal that light-induced carriers partition at the bimetallic interface, where electrons preferentially localize on Pt sites and holes on Au sites, thereby establishing a Lewis acid-base-like, charge-polarized heterointerface. Au sites preferentially mediate *CH3 adsorption and selective C-C coupling, while Pt sites facilitate H-2 evolution; the Pt-Au alloy synergy underpins C-C bond formation. This dual-site strategy harmonizes catalytic activity, selectivity, and stability, offering a generalizable approach for next-generation photocatalysts aimed at methane valorization.

Ru atomic clusters (AC) are promising cost-effective platinum-group-metal anode catalysts for the alkaline hydrogen oxidation reaction (HOR) in anion-exchange-membrane fuel cells (AEMFCs), yet their practical application remains limited by insufficient structural robustness and sluggish proton transport across the electrolyte/electrode interface. Herein, we report a design concept that leverages p-block indium single atoms with In-N3O1 coordination as electronic bridges to stabilize Ru AC and reconstruct a proton-conductive interfacial hydrogen-bond network for efficient and durable HOR catalysis in practical AEMFCs. We find that the bridged In-N3O1 sites establish strong covalent Ru-In anchoring interactions through pronounced d-p orbital hybridization, stabilizing Ru AC against coalescence and detachment for markedly improved operational durability. Meanwhile, electronic coupling between Ru AC and bridged In-N3O1 sites tunes surface oxophilicity of Ru to promote higher coverage of hydroxyl adsorbate species and drive dynamic reorientation of interfacial water from cation-bound states toward free water in the gap region, thereby reinforcing hydrogen-bond connectivity and enabling more efficient interfacial proton transport. The resulting Ru AC/In1@CNO delivers a mass activity of 7.17 A mgRu -1, surpassing Pt/C by 9.0-fold. Particularly, Ru AC/In1@CNO-based AEMFCs achieve a high peak power density of 1.33 W cm-2 and maintain stable operation for over 50 h at 500 mA cm-2.

Proton-coupled electron transfer (PCET), particularly the protonation step is widely recognized as the kinetic bottleneck in electrochemical CO 2 reduction (CO 2 RR). Modulating catalyst microstructures to accelerate protonation has thus emerged as a promising strategy to boost from CO 2 to CO selectivity. Here, we report ultrasmall Ni nanocluster catalysts (denoted as Ni 3 ─N─C) prepared via one-step pyrolysis of Ni-containing precursors under H 2 atmosphere. Compared to conventional Ni─N─C with symmetric Ni─N 4 motifs, Ni 3 ─N─C displays similar physicochemical characteristics—Ni loading, defect density, surface area—yet exhibits distinct local Ni coordination environments. These sub-nanoclusters markedly enhance CO 2 RR performance, delivering > 90% CO Faradaic efficiency (FE CO ) across −0.6 to −1.0 V versus RHE, with a peak FE CO of ∼95% at −0.8 V. Density functional theory calculations reveal that Ni 3 ─N─C substantially lowers the energy barrier for *COOH formation owing to altered adsorption configurations, thereby facilitating the rate-limiting protonation step. In situ FTIR measurements further confirm the accelerated *COOH formation on Ni 3 ─N─C surfaces. This work highlights the critical role of Ni sub-nanoclusters in PCET modulation and establishes a rational design principle for nanocluster-based catalysts in CO 2 RR.

In modern society with advanced electronic communication technology, electromagnetic wave absorbers are crucial in military and daily life. As electronic devices update rapidly, there's a need for absorbers with stronger absorption, wider bandwidth, and lighter weight. Emerging two-dimensional MXenes, with excellent dielectric properties and a unique nanosheet structure, have great microwave absorption potential. However, their practical use is limited by impedance mismatch due to high conductivity, causing poor reflection loss. To solve this, we report a novel NiO/NiFe2O4@Ti3C2Tx composite made by simple coprecipitation and 2-hour annealing at 400 degrees C. Core-shell NiO/NiFe2O4 nanocubes were evenly anchored on MXene nanosheets, introducing magnetic loss mechanisms and modulating dielectric response via defect engineering. The NiO/NiFe2O4@Ti3C2TX composite material reached a minimum reflection loss of-46.05 dB at 16.83 GHz, and the effective absorption bandwidth (EAB) was 6.39 GHz at a thickness of 2.2 mm. This work offers a new strategy for designing highperformance microwave absorbers for aerospace stealth coatings.