Rational regulation of the interfacial hydrogen-bond (HB) network to facilitate the rate-determining Volmer step involving water dissociation in alkaline hydrogen evolution reaction (HER) has emerged as a promising yet challenging strategy to break the intrinsic kinetic bottleneck. Herein, three zwitterionic COFs decorated with sulfonate, carboxylate, and phosphonate groups were designed and synthesized as interfacial microenvironment regulators to improve the HB network connectivity at the Pt/C electrode-electrolyte interface, leading to significantly accelerated HER kinetics. Specifically, a combination of in situ Raman spectroscopy, molecular dynamics (MD) simulations, and density functional theory (DFT) calculations demonstrates that COF interfacial regulators effectively disrupt the rigid HB network and induce polarization of interfacial water molecules, leading to a diminished interfacial K+ concentration and a markedly increased fraction of free water, which collectively accelerate interfacial mass transport and water dissociation kinetics. As a result, the optimized Pt/C@S-IMR catalyst delivers exceptional HER performance, achieving an overpotential of merely 66 mV at 100 mA cm−2 and a cell voltage of 1.85 V at 1 A cm−2 with a negligible degradation rate over 400-h in anion-exchange membrane water electrolysis (AEMWE). This study not only establishes zwitterionic COFs with different acidic groups as a versatile interfacial engineering strategy to regulate HB connectivity for efficient alkaline HER, but also provides a universal design paradigm for interfacial engineering in electrocatalysis.

Covalent organic frameworks (COFs) hold promise as ideal sulfur carrier materials for lithium-sulfur battery cathodes due to their well-defined pore structures and abundant heteroatom sites. Incorporating sulfur into COFs to form S@COF composites can overcome the reaction kinetic barriers inherent in sulfur cathodes and suppress the occurrence of the shuttle effect. However, COFs obtained through traditional solvothermal strategies often exhibit severe stacking, adversely affecting the electrochemical activity of the electrode. In this work, to obtain highly dispersed COF materials, highly dispersed COF nanoparticles with diameters of only 15-30 nm were successfully synthesized at room temperature by introducing surfactants into the reaction system, named TpTapt-NP. Furthermore, sulfur was successfully incorporated into the pores of TpTapt-NP to produce 70S@TpTapt-NP. Battery performance test results showed that 70S@TpTapt-NP retained a specific capacity of 447 mAh g-1 at a current density of 3C, demonstrating significantly improved rate performance compared to the 70S@TpTapt (283 mAh g-1) obtained by the solvothermal strategy. Furthermore, the distribution of relaxation time analysis indicated that TpTapt-NP promoted the exposure of N and O active sites and reduced mass transfer barriers in the electrode reaction process. This provides insights for the preparation of novel S@COF cathode materials for lithium-sulfur batteries.

Low-platinum (low-Pt) alloys are widely regarded as a promising alternative to commercial Pt/C catalysts, owing to their excellent balance of cost reduction and enhanced catalytic performance. However, they have long been hindered by a critical challenge-poor durability-primarily stemming from the dissolution of non-noble metals. Herein, we report a series of high-performance, stable low-Pt high-entropy intermetallic catalysts with the composition Pt(FeCoNi)3-xInx (where x = 0.25, 0.5, 0.75, 1), and systematically elucidate the role of entropy in regulating both the dissolution behavior of non-noble metals and the overall catalytic performance. The optimized high-entropy intermetallic Pt(FeCoNi)2.5In0.5 (PFCNI) exhibited significantly superior stability to its binary counterparts. PFCNI delivered an initial mass activity of 1.04 A mgPt-1, with only a 14.3% loss after 30 000 accelerated durability test (ADT) cycles-outperforming both commercial Pt/C and the binary reference catalysts. When integrated into a membrane electrode assembly (MEA), PFCNI retained 74.1% of its maximum power density after 30 000 accelerated stress test (AST) cycles. In contrast, the MEA based on PtNi3 (a binary counterpart) retained merely 16.8% of its maximum power density even after a shorter duration of 20 000 AST cycles. This study demonstrates that the high-entropy effect remarkably enhances the stability of typical PtM3-type catalysts for the acidic oxygen reduction reaction (ORR), thereby offering a promising strategy for the development of low-Pt catalysts with long-term durability.

ABSTRACT Efficient alkaline hydrogen evolution reaction (HER) electrocatalysis requires simultaneously accelerating sluggish water dissociation and facile hydrogen desorption, yet integrating these kinetically incompatible steps within a single catalytic site remains fundamentally challenging. Here we report a hollow‐spherical multiphasic ruthenium (Ru)/TiO 2 /Ti 3 C 2 T x MXene heterostructure that spatially decouples the elementary HER steps through an interfacial hydrogen spillover mechanism. Through comprehensive in situ spectroscopic investigations and theoretical simulations, we demonstrate that the unconventional phase‐engineered architecture enables Ru sites to efficiently dissociate water, while the Ti 3 C 2 T x MXene surface serves as a thermodynamically favorable platform for hydrogen recombination and release. Importantly, an interfacial TiO 2 bridge acts as a relay medium that dramatically lowers the hydrogen‐transfer barrier between the distinct catalytic domains, thereby establishing a continuous dual‐site reaction pathway across the heterogeneous interfaces. Consequently, the optimized catalyst delivers an ultralow overpotential of 13 mV at 10 mA cm −2 , together with outstanding operational stability over 320 h. Moreover, the assembled anion‐exchange membrane water electrolyzer requires only 1.66 V to achieve a current density of 1 A cm −2 . This work establishes an interfacial relay strategy for regulating hydrogen spillover across heterogeneous catalytic phases and provides a general framework for constructing advanced electrocatalysts with spatially cooperative reaction pathways.

Low-platinum high-entropy alloys (HEAs) have emerged as a highly promising alternative to commercial Pt/C for the oxygen reduction reaction (ORR). However, they suffer from transition metal leaching and structural degradation, particularly under the harsh acidic conditions of proton-exchange membrane fuel cell (PEMFC) operation. Herein, we propose an effective endogenous-alloying strategy, which involves incorporating cerium (Ce) as an endogenous alloying element into the HEA lattice, rather than as a discrete physical additive. This approach leverages the dynamic Ce3+/Ce4+ redox couple to effectively scavenge free radicals at the atomic level, fundamentally enhancing durability from within. The resultant low-platinum quinary catalyst Pt0.7Ce0.3FeCoNi (PCFCN) exhibits a disruptive "negative degradation" phenomenon in acidic media. After 30,000 accelerated durability test cycles, its mass activity not only showed no decay but also remarkably increased from 0.72 to 2.18 A mg(Pt)(-1), representing a 203% enhancement, far surpassing those of the control catalysts and state-of-the-art catalysts. This study not only reports a superior catalyst but also establishes a material paradigm for designing ultrastable high-entropy alloy electrocatalysts through endogenous rare-earth alloying.

Proton exchange membrane fuel cells (PEMFCs) demonstrate exceptional efficiency in converting hydrogen into electricity and hold great promise for mitigating carbon emissions. However, the high loading of platinum (Pt) (0.2–0.35 mg Pt cm −2 ) in the cathode catalytic layer (CL) poses a significant obstacle to the commercialization of PEMFCs. Although current research has succeeded in reducing Pt usage in the cathode CL, carbon corrosion remains a major issue that leads to decreased output power density and shortened service life. The enhancement of support stability poses a greater challenge compared to the improvement of intrinsic stability in Pt-based alloys, primarily due to the thermodynamic instability of carbon during practical operating conditions. Recently, extensive efforts are dedicated to exploiting advanced carbon supports through the utilization of innovative nanostructure design and synthesis techniques, as well as profound mechanistic insights. This review highlights the intriguing advancements in the modification and synthesis of carbon materials, while also summarizing the underlying mechanisms and potential factors that impact the corrosion reaction of carbon. The general ideas and strategies for the development of carbon materials with desirable nanostructures and physicochemical properties are outlined in detail to design low-Pt CL with highly efficient mass transfer and superior stability.

With the advantages of simple preparation, cost-effectiveness, abundant raw materials, and environmentally friendly properties, hard carbon is the only commercially available anode material for sodium-ion batteries. However, its unstable capacity is attributed to the complex physicochemical characteristics of the precursors, the intricate and difficult-to-control microstructure, and the debated mechanisms of sodium storage. Although recent reports have revealed a strong correlation between closed pores and the capacity of hard carbon in the low-voltage plateau region, systematic overviews of this relationship remain scarce. This review examines the microstructural properties and precursor selectivity of hard carbon materials and outlines the strategies for the research and development of closed pores, including design theory and characterization. Finally, it summarizes the technical bottlenecks faced by the closed pore research and looks forward to the future development directions.

Dendrite formation and ongoing side reactions on the zinc anode are critical issues that hinder the application of zinc-ion batteries. Herein, a fluorine-containing carbon coating is applied to the zinc anode surface via laser irradiation. This coating enhanced the regulation of Zn2+ diffusion and nucleation behavior on the anode surface, promoting stable (002)-textured Zn deposition and reduction in side reactions. The strongly coupled coating enabled highly stable and reversible zinc stripping/plating for over 721 hours in Zn/Zn symmetric batteries at 5 mA cm-2 and 2.5 mA h cm-2. Moreover, the assembled full battery retained 80% of its initial capacity after 5500 cycles at a current density of 1 A g-1. Thus, it was demonstrated that surface modification with fluorine-containing carbon can improve the stability and reversibility of Zn anodes, thus accelerating the commercialization of ZIBs.

Metal-doped molybdenum sulfide (MoS2) shows promise for achieving platinum-like catalytic activity in the hydrogen evolution reaction (HER) of electrocatalysis, though the proton and electron transfer kinetics remain poorly understood. In this study, we investigated the HER kinetics and mechanism on both pristine and vanadium(V)-doped MoS2 catalysts using silicotungstic acids as electron mediators. V-doped MoS2 exhibits an HER rate approximately 5 times that of MoS2 (696.4 vs 140.7 mmolH2 g-1 min-1). This enhancement is attributed to accelerated proton adsorption and transfer kinetics, driven by an increased number of active sites and favorable proton transfer in the Volmer step. Moreover, silicotungstic acids mediate electron transfer through an inner-sphere mechanism, showing identical reaction orders on both pristine and V-doped MoS2. Electrochemical Tafel slopes reveal that H2 evolution follows a Volmer-Heyrovsky mechanism, regardless of V doping. This work highlights the significance of proton adsorption and transfer kinetics in enhancing HER rates.

The development of advanced support is conducive to promoting the practical application of fuel cells but remains an enormous challenge in terms of stabilizing catalyst particles and enabling improved accessibility to O-2. Beyond solid carbon black and conventional porous carbon, we demonstrate a new type of mesoporous bowl-like carbon support with a high specific surface area of over 1200 m(2) g(-1) and similar to 4 nm pore. Both rotating disk electrode and membrane electrode assembly (MEA) tests show that BC-supported Pt3Co (Pt3Co/BC) catalyst greatly outperforms hollow porous carbon spheres and solid carbon spheres supported Pt3Co catalysts. The Pt3Co/BC catalysts exhibited remarkable performance as cathode catalyst in MEA, achieving a comparable open-circuit voltage of approximately 0.95 V under H-2-air condition and a current density of 1.3 A cm(-2) at 0.6 V with a loading of only 0.2 mg(Pt) cm(-2). Diffusion simulations and physical characterizations demonstrate that the high porosity and highly accessible pore structure of BC support facilitate the uniform distribution of catalyst particles and enhance the mass transport of O-2, thereby resulting in a significant improvement in catalytic activity and durability. This work provides new insights into the influence of support shape on mass transport of reactants and electrochemical performances of the catalyst in MEA. (c) 2025, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Challenges including low stability, excessive thickness, a low ionic conductivity of current solid–state electrolytes, and large interfacial resistance in solid–state lithium batteries (SSLBs) hinder their application. Herein, an ultra–thin electrolyte (∼20 μm) was prepared by using expanded porous polytetrafluoroethylene (ePTFE) as a framework and filling the pores with a hybrid electrolyte; it exhibited a high stability, mechanical strength, flexibility, and ionic conductivity (0.27 mS cm−1). A new mechanism for fast lithium-ion conduction in the composite electrolyte was creatively proposed, whereby the interface orients and concentrates lithium ions to accelerate ion transport. An electrolyte–electrode(s) assembly (EEA) was developed by directly spraying active material(s) with highly dispersed electrolytes on the electrolyte. EEA–based copper– and aluminum–free SSLBs with or without a low-dose liquid electrolyte achieved an excellent performance at room temperature. Furthermore, EEA–series–connected pouch batteries demonstrated high voltage, safety, and performance, making our ultra–thin electrolyte and EEA promising for the development of SSLBs.

Li-CO2 batteries have attracted considerable attention worldwide because of their high theoretical energy density and ability to capture CO2. However, the sluggish redox reaction kinetics, high overpotential, and insufficient durability of the cathodes remain a considerable challenge. In this study, we designed and prepared a Cu and Cr dual-atom co-doped carbon catalyst by chemically depositing both metal atoms on hollow bimodal porous carbon nanocages. For the batteries with our optimal sample as a cathode, a specific capacity of 23,928 mAh g- 1, the lowest overpotential of only 0.8 V, and an ultralong cycle life of 338 cycles are achieved. Our developed sample exhibits superior characteristics over other existing cathode catalysts for Li-CO2 batteries. The synergetic effect between Cu and Cr was revealed by characterization and calculation, as well as its promotion mechanism. Meanwhile, the interconnected carbon nanocages provide excellent space for hosting discharge products while facilitating the access of CO2 and Li+ to the active sites. The encouraging performance of this work offers a new pathway for enhancing the performance of catalysts by introducing synergetic effects into the catalysts for Li-CO2 batteries.

Aqueous zinc-ion batteries (ZIBs) have attracted burgeoning attention and emerged as prospective alternatives for scalable energy storage applications due to their unique merits such as high volumetric capacity, low cost, environmentally friendly, and reliable safety. Nevertheless, current ZIBs still suffer from some thorny issues, including low intrinsic electron conductivity, poor reversibility, zinc anode dendrites, and side reactions. Herein, conductive polyaniline (PANI) is intercalated as a pillar into the hydrated V2O5 (PAVO) to stabilize the structure of the cathode material. Meanwhile, graphene oxide (GO) was modified onto the glass fiber (GF) membrane through simple electrospinning and laser reduction methods to inhibit dendrite growth. As a result, the prepared cells present excellent electrochemical performance with enhanced specific capacity (362 mAh g−1 at 0.1 A g−1), significant rate capability (280 mAh g−1 at 10 A g−1), and admirable cycling stability (74% capacity retention after 4800 cycles at 5 A g−1). These findings provide key insights into the development of high-performance zinc-ion batteries.

Advancing the design of cathode catalysts to significantly maximize platinum utilization and augment the longevity has emerged as a formidable challenge in the field of fuel cells. Herein, we rationally design a high entropy intermetallic compound (HEIC, Pt(FeCoNiCu) 3 ) for catalyzing oxygen reduction reaction (ORR) by an efficient machine learning stategy, where crystal graph convolutional neural networks are employed to expedite the multicomponent design. Based on a dataset generated from first-principles calculations, the model can achieve a high prediction accuracy with mean absolute errors of 0.003 for surface strain and 0.011 eV atom −1 for formation energy. In addition, we identify two chemical features (atomic size difference and mixing enthalpy) as new descriptors to explore advanced ORR catalysts. The carbon supported Pt(FeCoNiCu) 3 catalyst with small particle size is successfully synthesized by a freeze-drying-annealing technology, and exhibits ultrahigh mass activity (4.09 A mg Pt −1 ) and specific activity (7.92 mA cm −2 ). Meanwhile, The catalyst also shows significantly enhanced electrochemical stability which can be ascribed to the sluggish diffussion effect in the HEIC structure. Beyond offering a promising low-Pt electrocatalysts for fuel cell cathode, this work offers a new paradigm to rationally design advanced catalysts for energy storage and conversion devices.

Single-atom metal-doped M-N-C (MFe, Co, Mn, or Ni) catalysts exhibit excellent catalytic activity toward oxygen reduction reactions (ORR). However, their performance still has a large gap considering the demand for their practical applications. This study reports a high-performance dual single-atom doped carbon catalyst (HfCo-N-C), which is prepared by pyrolyzing Co and Hf co-doped ZIF-8 . Co and Hf are atomically dispersed in the carbon framework and coordinated with N to form Co-N4 and Hf-N4 active moieties. The synergetic effect between Co-N4 and Hf-N4 significantly enhance the catalytic activity and durability of the catalyst. In an acidic medium, the ORR half-wave potential (E1/2) of the catalyst is up to 0.82 V , which is much higher than that of the Co-N-C catalyst without Hf co-doping (0.80 V). The kinetic current density of the catalyst is up to 2.49 A cm-2 at 0.85 V , which is 1.74 times that of the Co-N-C catalyst without Hf co-doping. Moreover, the catalyst exhibits excellent cathodic performance in single proton exchange membrane fuel cells and Zn-air batteries. Furthermore, Hf co-doping can effectively suppress the formation of H2O2, resulting in significantly improved stability and durability. A high-performance dual single-atom doped carbon catalyst is prepared by pyrolyzing Co and Hf co-doped ZIF-8 metal-organic frameworks. Owing to the synergistic effect of the Co-N4 and Hf-N4 moieties, the dual single-atom doped carbon shows greatly enhanced catalytic activities toward oxygen reduction in acidic medium.image

Tuning surface strain has been proven to be an efficient strategy for improving the kinetics of the oxygen reduction reaction of Pt-M electrocatalysts (M = non-noble metals). However, it remains a grand challenge to achieve optimal compressive strain, particularly on a platform of low-Pt nanocrystals. Herein, we report a novel approach involving the partial substitution of a Pt site with Ga, resulting in the development of a high-performance L10-type Pt0.8Ga0.2Co intermetallic catalyst. The incorporation of Ga not only fine-tunes the surface strain to approach the optimum region of the theoretical volcano plot but also facilitates the formation of a more stable intermetallic structure dynamically. This enhancement significantly improves long-term electrochemical durability. Pt0.8Ga0.2Co/C exhibits a markedly improved intrinsic activity of 3.39 mA cm-2 and, more importantly, a high mass activity of 0.77 A mgPt -1 at 0.90 V in a fuel cell, surpassing the performance of most previously reported L10 Pt-based intermetallics. Notably, catalytic durability is confirmed through only 28% mass activity loss after 30,000 potential cycles (vs 40% loss for the DOE target). This work paves the way for the development of promising low-Pt electrocatalysts for efficient energy conversion devices.

Covalent organic framework (COF) materials with redox activity have emerged as promising electrode materials for lithium-ion batteries.