The direct coupling of carbon dioxide and nitrates into urea powered by renewable electricity offers a promising alternative to the conventional Bosch-Meiser process, enabling integrated carbon reduction, energy storage, and high-value nitrates conversion. However, the intrinsically complex multi-step reaction pathways and kinetically demanding C–N bond formation result in limited urea activity and selectivity. Herein, we propose a distance-regulated cooperative C–N coupling strategy in urea electrosynthesis by tuning the inter-site spacing of atomically dispersed iron catalysts supported on carbon nitride (Fe1/C3N4). The interatomic distance of Fe/Fe sites is precisely controlled from 103.1 to 6.3 Å. Excessive separation (≥14.2 Å) impedes the second C–N coupling step, whereas overly short distances (≤1.8 Å) alter the adsorption of *CO and *NH from linear to bridged configurations, hindering the first C–N bond formation. An optimal Fe/Fe distance (∼8.3 Å) balances electronic modulation and spatial proximity, enabling efficient C–N coupling. The optimized catalyst delivers a urea yield rate of 46.1 mmol g−1 h−1 with a Faradaic efficiency of 38.6% at −0.9 V versus RHE, and achieves 65.2% under pulsed electrolysis. In situ spectroscopy and theoretical calculations indicate that the regulated inter-site distance optimizes adsorption configurations and promotes C–N coupling. This study provides insight into distance-dependent synergistic effects in single-atom catalysts and offers a strategy for designing efficient electrocatalysts for complex reactions.

Due to the extremely similar molecular sizes and melting and boiling points of acetylene (C2H2) and carbon dioxide (CO2), their efficient separation and purification have long been significant challenges in the field of industrial purification. Based on the ligand construction strategy, this study selected 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine as the main ligand and coordinated it with 3-methyl-1H-1,2,4-triazole and 3,5-dimethyl-1H-1,2,4-triazole, respectively, to assemble metal-organic frameworks (MOFs), successfully preparing two double-walled MOF crystal materials: Zn-TATB-fmtrz and Zn-TATB-dmtrz. Among them, Zn-TATB-fmtrz has a larger pore size (11.64 × 6.63 Å), while the pore size of the comparative material Zn-TATB-dmtrz is only 4.94 × 4.30 Å; in addition, the specific surface area of Zn-TATB-fmtrz (1403.4 m2/g) is also significantly higher than that of Zn-TATB-dmtrz (826.4 m2/g). Benefiting from the above structural advantages, both MOF materials can achieve efficient separation of C2H2/CO2. Systematic adsorption tests indicate that under conditions of 298 K and 1 bar, the maximum acetylene adsorption capacity of Zn-TATB-fmtrz reaches 58.6 cm3/g, much higher than the 37.5 cm3/g of Zn-TATB-dmtrz; moreover, the adsorption selectivity of Zn-TATB-fmtrz for C2H2/CO2 is 3.0, slightly better than 2.9 for Zn-TATB-dmtrz. Dynamic breakthrough experiments based on real binary mixtures further visually confirm that Zn-TATB-fmtrz shows potential for practical C2H2/CO2 separation.

The purification of C2H2, particularly the selective separation of C2H2 from C2H2/CO2 or C2H2/C2H4 mixtures, is of paramount importance for the production of high-purity C2H2 and C2H4 products. Nevertheless, this process remains energy-intensive and presents considerable challenges. Here, the interpenetration strategy has been employed to synthesize a stable dual-ligand MOF designated as Zn-btb-fmtrz. This framework not only preserves the intrinsic interpenetrating properties associated with the 1,3,5-tri(4-carboxyphenyl)benzene (H3btb) ligand but also retains the abundant active sites and functional groups linked to the 3-methyl-1H-1,2,4-triazole (fmtrz) ligand. The interpenetration structure of Zn-btb-fmtrz significantly enhances structural stability, and the adsorption capacity for C2H2 in samples treated with acidic-basic solution is largely preserved. And the highdensity adsorption sites of Zn-btb-fmtrz facilitate strong electrostatic interactions with C2H2, leading to elevated C2H2 uptake (78.9 cm3/g), moderate C2H2/CO2 selectivity (2.6), and an improved C2H2/CO2 adsorption ratio (2.2). Theoretical calculations indicate that the presence of abundant N/O sites is crucial for facilitating strong interactions between the structure and guest acetylene molecules. Moreover, breakthrough experiments validate the exceptional separation capabilities of C2H2/CO2 and C2H2/C2H4 mixtures. These results, coupled with their outstanding stability in terms of water/chemical resistance, thermal endurance, and cycling performance, underscore their potential for industrial applications in acetylene purification.

Conjugated metal-organic frameworks (CMOF) can be utilized as electrochemical sensor for glucose. Herein, we develop a simple one-pot method to compositing Ni3(HHTP)2 CMOF with graphene oxide (GO). The functional groups on GO enable the in-situ growth of CMOF and the strong it-it interaction induces the CMOF into regular nanorod array with the optimized GO contents. On the contrary, CMOF without GO grows in disordered nanorods. The regular CMOF nanorod array allows the rapid access of glucose molecule through the 1D channel to the active centers of Ni for rapid and accurate sensing. The optimized Ni3(HHTP)2-GO5 exhibits excellent glucose sensing properties with high sensitivities of 9657.7 and 858.57 mu AmM-1 cm-2 in the measuring ranges of 0.005-0.15 and 0.15-4 mM. A rapid response time of less than 0.5 s and a low detection limit of 0.35 mu M for glucose detection are achieved. The sensing material is successfully applied to real beverage samples, demonstrating its excellent practical applicability. Beyond this, it demonstrates remarkable stability and reproducibility, making it suitable for accurate glucose detection in complex environments.

The efficient separation of acetylene (C2H2) and carbon dioxide (CO2) is of major practical importance but remains difficult because of their analogous physical properties. The dual-ligand strategy provides an effective approach to tailor pore structure and chemical microenvironments for enhanced functionality. Nevertheless, the structural controllability of metal-organic frameworks (MOFs) assembled from tetracarboxylic acids and azole ligands remains challenging. Herein, we report a unique pillar-layered MOF, Zn-TCPB-dmtrz, constructed based on a dual-ligand strategy, demonstrating the efficient separation of C2H2/CO2. The coordination of different ligands generates 1D [Zn4N6]n chains, which function as pillars to interconnect 2D layers into a rare pillar-layered structure. The combination of abundant N/O sites and hydrophobic pore environment achieves high C2H2 adsorption capacity and excellent C2H2/CO2 separation ability. Furthermore, its relatively low C2H2 Qst, competitive thermal stability, and recyclability underscore its practicality for C2H2/CO2 separation. This study enriches the structural diversity of pillar-layered MOFs and demonstrates the controllable dual-ligand strategy based on tetracarboxylic acid and dmtrz ligands for advanced gas separation.

Despite a great many modifications, Pt-based catalysts are still suffering from the trade-off among cost, activity, and stability, continuously limiting their widespread utilization in the hydrogen evolution reaction (HER). Herein, we proposed a PtNiFe-NiFe LDH@NF catalyst constructed via in situ reduction of a NiFe alloy on a robust NiFe hydroxide, in which a trace amount of Pt (0.223 mg cm-2) was precisely incorporated into the alloy lattice through substitutional incorporation. This architecture effectively stabilizes the alloy phase and suppresses Pt agglomeration under industrial-level current densities. Benefitting from strong interactions between Pt and Ni/Fe, a modified electron pathway from Ni/Fe to Pt facilitates unique electron-rich Pt delta- species with a downshifted d-band center, and better kinetics for intermediates evolution. Impressively, the PtNiFe-NiFe LDH@NF delivers an overpotential of 48 mV at 100 mA cm-2 (5.89 times higher mass activity than that of commercial Pt/C) and superior durability of 1600 h at 1 A cm-2, exhibiting more exceptional practicality than normal. Furthermore, the assembled anion exchange membrane electrolyzer achieves 1 A cm-2 at 1.76 V and maintains stability for 800 h, demonstrating an effective approach for efficient utilization of noble metal and access to industrial-scaled HER catalysts.

ABSTRACT To fully unlock catalytic potential in the oxygen evolution reaction (OER), it is essential to guide the reconstruction process, orienting the evolution from the initial amorphous state into a more potent amorphous structure. We develop an amorphous cobalt coordination polymer (aCo) pre‐catalyst via monodentate end‐capping. In‐situ synchrotron radiation X‐ray diffraction reveals that CH 3 CN coordination disrupts the long‐range topological order while preserving local motifs. The obtained metastable amorphous structure redirect spontaneous surface reconstruction into an amorphous cobalt oxyhydroxide (a‐CoOOH) active layer due to strong d–π* interactions with the lower energetic barrier (−8.175 eV) compared to the crystalline phase on its counterpart (−7.441 eV). The unique amorphous‐to‐amorphous transformation effectively activates lattice oxygen within the metastable framework, switching the OER pathways from the adsorbate evolution mechanism to a lattice oxygen‐mediated mechanism and consequently enhancing OER efficiency and stability. The optimized amorphous aCo can achieve an overpotential of 186 mV at 10 mA cm −2 , much lower than those of RuO 2 (233 mV) and crystalline cCo (308 mV), and it demonstrates stability of over 100 h at 2 A cm −2 . This strategy offers a directed surface‐induced approach for designing next‐generation OER electrocatalysts, providing fundamental insights into the correlation between lattice oxygen activity and structural long‐range disorder.

Designing and tailoring porous materials to realize the precise separation of C2H2, C2H4 and CO2 with nearly identical kinetic diameters is an extremely challenging research task. In this study, a novel microporous metal-organic framework (MOF) designated UPC-523 (Zn3(H4edda)2·DMF) has been synthesized by employing 5,5'-(ethane-1,2-diylbis(oxy))diisophthalic acid (H4edda), which is constructed with ethylene ether linkages (-O-CH2-CH2-O-). This rational design strategy employs ethylene ether moieties to construct a highly electronegative pore microenvironment within the framework. UPC-523 is endowed with abundant electronegative sites, the uncoordinated oxygen atoms in the confined pores selectively capture C2H2 from CO2 and C2H4 through hydrogen-bonding interactions, enabling it to achieve selective adsorption of C2H2. At 298 K and 100 kPa, this MOF exhibits a C2H2 adsorption capacity of 44.9 cm3/g, coupled with a moderate isosteric heat of C2H2 adsorption (Qst) of 33.7 kJ/mol, a property conducive to the direct desorption and regeneration of UPC-523. The IAST selectivities of C2H2/C2H4 (v/v = 50/50) and C2H2/CO2 (v/v = 50/50) are 2.1 and 3.4, respectively, comparable to the majority of reported MOFs under identical conditions. Dynamic breakthrough experiments reveal that UPC-523 can efficiently separate C2H2 from C2H2/CO2 or C2H2/C2H4 mixtures.

ABSTRACT Designing and tailoring porous materials to realize the precise separation of C 2 H 2 , C 2 H 4 and CO 2 with nearly identical kinetic diameters is an extremely challenging research task. In this study, a novel microporous metal‐organic framework (MOF) designated UPC‐523 (Zn 3 (H 4 edda) 2 ·DMF) has been synthesized by employing 5,5'‐(ethane‐1,2‐diylbis(oxy))diisophthalic acid (H 4 edda), which is constructed with ethylene ether linkages (‐O‐CH 2 ‐CH 2 ‐O‐). This rational design strategy employs ethylene ether moieties to construct a highly electronegative pore microenvironment within the framework. UPC‐523 is endowed with abundant electronegative sites, the uncoordinated oxygen atoms in the confined pores selectively capture C 2 H 2 from CO 2 and C 2 H 4 through hydrogen‐bonding interactions, enabling it to achieve selective adsorption of C 2 H 2 . At 298 K and 100 kPa, this MOF exhibits a C 2 H 2 adsorption capacity of 44.9 cm 3 /g, coupled with a moderate isosteric heat of C 2 H 2 adsorption ( Q st ) of 33.7 kJ/mol, a property conducive to the direct desorption and regeneration of UPC‐523. The IAST selectivities of C 2 H 2 /C 2 H 4 (v/v = 50/50) and C 2 H 2 /CO 2 (v/v = 50/50) are 2.1 and 3.4, respectively, comparable to the majority of reported MOFs under identical conditions. Dynamic breakthrough experiments reveal that UPC‐523 can efficiently separate C 2 H 2 from C 2 H 2 /CO 2 or C 2 H 2 /C 2 H 4 mixtures.

Sandwich-structured hydrogel supercapacitors (SCs) have recently attracted considerable attentions as promising candidates for flexible electronics. Nevertheless, their practical developments are frequently impeded by interfacial challenges, including weak adhesion, interlayer slippage under repeated deformation, and the inherent trade-off between electrochemical performance and mechanical flexibility. Herein, a flexible integrated polypyrrole-graphene oxide (PPy-GO) supercapacitor with intimate interfaces is fabricated via a repeated in-situ growth strategy. The incorporation of GO effectively modulates the microstructure of PPy, thereby optimizing ion transport pathways and enhancing the overall electrochemical properties. As an all-gel supercapacitor, it delivers a high areal capacitance of 931.7 mF cm-2, excellent energy density (186.34 mu Wh cm-2) and power density (602.72 mu W cm-2), along with remarkable cycling stability. Furthermore, without any structural modification, the device can operate as a sensitive self-powered strain sensor with rapid response (0.2 s), enabling real-time monitoring and transmission of physiological signals and diverse human motions, while maintaining exceptional robustness and signal reliability. This study provides a feasible design paradigm for multifunctional hydrogel systems that integrate high-performance energy storage and sensing capabilities, offering new opportunities for next-generation wearable motion recognition and health-monitoring electronics.

Electrocatalytic urea production from nitrate (NO3-) and carbon dioxide (CO2) provides a promising alternative to the traditional energy-intensive industrial process. However, promoting electrocatalytic carbon-nitrogen coupling and suppressing side reactions remains challenging. Here we report an efficient urea synthesis via electrochemical coupling of NO3- and CO2 using entangled iron porphyrins in three-dimensional covalent organic frameworks. The porous iron catalyst concentrates and cooperatively activates reactants, achieving a high Faradaic efficiency of 90.0%, a nitrogen selectivity of 92.4% and nearly 100% carbon selectivity. The catalyst achieves a urea yield rate of 135.6mmolg(cat)(-1)h(-1), while maintaining activity for >100 h. Experiments and theoretical calculations suggest the plentiful Fe-N-4 sites within porphyrins efficiently facilitate the conversions of CO2 to *CO and NO3- to *NH2, and the spatial localization of twin iron sites overcomes the unordered transfer of intermediates, enabling vectored carbon-nitrogen coupling.

ABSTRACT Flexible supercapacitors based on hydrogels have developed rapidly, although they still face issues such as low voltage window and easy freezing of gel at low temperatures. Herein, the biological zwitterionic betaine is utilized to lock water molecular for widening the voltage window and improving anti‐freezing performances of PAM/PEG/CS/Betaine‐composited hydrogels (named as PPCBx, x denotes the amount of betaine). By optimizing the betaine contents, the PPCB0.03 hydrogel reaches the stress limit of 102.04 KPa at the tensile strain limit of 400%, with a high ionic conductivity of 2.87 S m−1. The ionic conductivity remains at 0.45 and 0.15 S m−1 even at −30 and −50°C. The assembled supercapacitor can endow a high voltage window reaching 2.4 V. The specific area capacity of the device is 585.45 mF cm−2 at the current density of 2 mA cm−2 and maintains 82% after 9000 cycles. The specific capacity can still remain 191.24 mF cm−2 even at −50°C, demonstrating its remarkable anti‐freezing feature. Assembled with solar cells, the device can be successfully utilized for energy harvesting.

Efficient and stable electrocatalysts are essential for seawater splitting to sustain electrolysis without chloride corrosion, particularly at the anode. Furthermore, the oxygen evolution reaction (OER) requires high overpotential due to the universal scaling relationship. Herein, molybdenum doping FeNi2 Se4 with lattice distortion is proposed to break the scaling relationship. Mo-FeNi2 Se4 shows high performance in direct seawater electrolysis and achieves current densities of 10 and 100 mA cm-2 at overpotentials of 190 and 250 mV, respectively, together with high OER selectivity and long-term stability. It is found that the lattice distortion induced by Mo doping in (3 1 0) plane of FeNi2 Se4 , leads to a decrease in the d-band center and the adsorption energy of *O, which not only breaks the scaling relationship of OER but also lowers the energy barriers of rate-determining step. Moreover, it enhances the corrosion resistance to Cl-, and realizes the high-efficiency seawater electrolysis driven by photovoltaic. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Conventional crystalline metal-organic frameworks (MOFs) have rigid, ordered frameworks that hinder structural reconstruction under OER conditions, resulting in limited exposure of active sites. To address these challenges, we develop an amorphous, high-entropy Co-based MOF (aHE-MOF) by atomically dispersing Fe, Ni, Cu, and Zn into MIL-88(Co) with the assistance of 2-methylimidazole (2-MeIM). The synergistic interactions of amorphous and high-entropy materials could tune the electronic structure and provide abundant defect sites, thereby inducing the uniform formation of catalytically active CoOOH phases to accelerate the OER kinetics. In situ studies reveal that the aHE-MOF irreversibly transforms into a CoOOH/aHE-MOF heterostructure under OER conditions, optimizing the d-band center of Co and intermediate adsorption. The reconstructed catalyst exhibits excellent OER activity in alkaline and simulated seawater electrolytes, achieving low overpotentials of 191 mV@10 mA·cm-2 and 333 mV@100 mA·cm-2 in alkaline freshwater, respectively, and remarkable long-term stability (∼100 h) with minimal performance decay. Operando Raman spectroscopy and DFT calculations confirm that the irreversible phase reconstruction and associated electronic modulation drive the enhanced OER performance.

Two-dimensional metal-organic frameworks (2D MOFs) show exceptional promise for the oxygen reduction reaction (ORR) due to their high-density exposed metal sites and tunable structures. However, enhancing electrocatalytic activity and elucidating underlying mechanisms remain key challenges in catalyst design. This study employs heterometallic doping in Co-HHB (HHB = 1,2,3,4,5,6-hexahydroxybenzene) to construct bimetallic MOFs TMxCo3-x (TM = Fe, Ni, Cu; x = 1, 2). Based on density functional theory (DFT) calculations encompassing geometric optimization, adsorption energy, and reaction free energy, we establish that the Cu1Co2 configuration delivers superior ORR activity, achieving an ultralow theoretical overpotential of 0.20 V. Electronic structure analysis reveals that Cu doping modulates the valence electron configuration of Co sites, optimizing intermediate adsorption strength. This synergistic effect facilitates the ORR pathway by balancing adsorption/desorption energetics. Therefore, bimetallic regulation in two-dimensional MOFs is an effective modification strategy for enhancing electrocatalytic ORR activity, and the intrinsic electronic structure regulation mechanism provides valuable theoretical insights for the design of high-performance electrocatalysts.

Electrochemical nitrate conversion to ammonia driven by sustainable green electricity is regarded as a promising supplement to the traditional Haber–Bosch process. However, it is still restricted by the low NH 3 yield rate and Faradaic efficiency. Here, we propose a continuous intermediates spillover strategy by constructing dual single‐atom alloy to boost ammonia yield rate and Faradaic efficiency. The intermediates continuously spill over back and forth on the atomically dispersed Mo and Fe sites in Pd lattice, which adaptively experiences low energy barrier for each elementary step in nitrate conversion. As a result, the synthesized dual single‐atom alloy metallene delivered an NH 3 yield rate of 13.4 mol g cat. −1 h −1 , and Faradaic efficiency of 94.6%, as well as remarkable cycling stability of 300 h. Furthermore, the dual single‐atom alloy metallene was assembled into a zinc‐nitrate battery as the cathode, which delivered an output voltage of 1.477 V, and the maximum output power density of 13.4 mW cm −2 .

High-purity acetylene (C2H2) is indispensable in the chemical industry. However, C2H2 produced via the calcium carbide process contains trace CO2 impurities, necessitating purification. Due to their comparable molecular dimensions (3.3 × 3.3 × 5.7 Å3 for C2H2 vs 3.2 × 3.3 × 5.4 Å3 for CO2), achieving effective separation remains a challenge. For the first time, this work achieves efficient C2H2/CO2 separation in an ultra-stable metal-organic framework (MOF) featuring a synergistic rigid-flexible structure, characterized by a 2-fold interpenetrating MOF that incorporates an unprecedented [Zn4N9]n chain. The rigid molecular chains ensure stability, as the structure is retained after immersion in strong acidic environments for one month. The 2-fold interpenetration architecture imparts controlled structural flexibility to the framework, triggering a stimuli-responsive gate-opening phenomenon upon C2H2 adsorption. This dynamic structural transformation induces a significant pore environment modulation, as quantified by the expansion of the pore limiting diameter (PLD) from 3.09 to 3.34 Å. The precisely tuned aperture demonstrates exceptional molecular sieving capabilities, permitting selective C2H2 permeation while effectively rejecting CO2 molecules due to their differential kinetic diameters. Integrated analysis of gas adsorption isotherms, theoretical calculations, breakthrough experiments, and stability assessments synergistically confirm the structural robustness and selective separation efficacy of this interpenetrated framework.

Multicarbon alcohols produced through photochemical and electrochemical CO2 reduction reactions (CO2RR) are promising alternatives to fossil fuels; however, their selectivity and efficiency remain low due to the high energy barrier for C-C coupling and the competition from hydrocarbon production. Here, we present a strategy to enhance ethanol efficiency and selectivity via cooperative catalysis in porous structures for photoelectrochemical (PEC) CO2RR. Using a coordination-templated strategy, we synthesized single crystals of MOF-COF (MOCOF) hybrids with metalloporphyrins, with their structures determined by single-crystal 3D electron diffraction. The porous frameworks featuring adjacent confined metalloporphyrins efficiently capture and cooperatively activate CO2, achieving outstanding PEC CO2-to-ethanol conversion. Particularly, the Pt-MOCOF delivers a Faradaic efficiency (FE) of 83.5% at -1.0 V with 91.7% carbon selectivity, surpassing state-of-the-art COF or MOF catalysts and ranking it among the top-performing catalysts. The catalyst system displays remarkable stability, maintaining 95% of its activity after 100 h of continuous operation. Experiments and theoretical calculations revealed that the cooperative catalyst enriches and stabilizes intermediates in the channels, guiding the reaction pathway toward ethanol production.

Seawater electrolysis is an effective way for large-scale green hydrogen. Nevertheless, the anode suffers from the severe corrosion of Cl- and Br- during oxygen evolution, which gives rise to the issues of narrow-deep pits and shallow-wide pits, respectively. Herein, an anti-corrosion strategy is presented by self-adapting oxyanion armor to prevent the high valence active sites from Cl- and Br- corrosion. The core-shell FeNi2Se4@NiFe-Phy is reconstructed to active species NiFeOOH covered by an oxyanion layer composed of phosphoric and carbonate. The aimed anode exhibits remarkable efficiency, achieving current densities of 10 and 200 mA cm(-2) at overpotentials of merely 220 and 277 mV, respectively. Notably, it shows unparalleled durability, enduring without any discernible degradation following rigorous testing for 400 h at 400-1000 mA cm(-2) in alkaline simulated seawater, as well as natural seawater. A combination of density functional theory calculations and molecular dynamics simulations further confirms the bifunctional enhancement of oxyanion armor on NiFeOOH surface. At a current density of 200 mA cm(-2), the alkaline seawater electrolyzer has significant energy efficiency, consuming merely 4.61 and 4.27 kWh Nm(-3) H-2 at room temperature and 80 degrees C, respectively. This work offers an efficacious surface corrosion resistance strategy for anode protection during seawater electrolysis.