Olefin-linked covalent organic frameworks (ccCOFs) have shown great advantages in the community since discovery. However, the synthesis of ccCOFs highly relies on unsaturated heteroatom-involved segments (uSHS) to activate C─H bond to produce carbanion and to further condense with aldehydes. Such electron-withdrawing uSHS have long hindered the wide applications of ccCOFs in optoelectronic devices due to the strong electron-withdrawing effect. In this work, we report a carbenium-involved synthesis of ccCOFs without uSHS' participating. As-synthesized ionic ccCOFs show good crystallinity and ultra-narrow bandgap down to 1.03 eV without introducing complicated donor-acceptor building blocks. Such ccCOFs can also be directly synthesized as uniform films on different substrates, for example, glass, silicon wafer, Au, and so on. Most impressively, the device Au/2DPPPV-102/Al exhibits 32 distinct conductance states under low-voltage sweeps and each conductance state demonstrated excellent non-volatility and could be maintained stably for over 5000 s, which are typical features of memristor. A convolutional neural network was implemented using a 32-conductance-state memristor array and applied to image recognition, yielding recognition accuracies exceeding 90% for five randomly selected images.

Covalent organic frameworks (COFs) are a unique class of porous crystalline materials featuring precisely ordered structures and well-tunable porous channels as well as abundant active functional groups, which enable them as promising membranes for high-performance gas separation. However, construction of thin COF membranes to simultaneously realize high-permeability and high-selectivity He separation has remained a challenge. Here, we report the synthesis of ultrathin (<5 nm thick) porphyrinyl two-dimensional polyimine (Por-2DPI) COF membranes, which comprise single-crystalline domains and highly ordered, vertically aligned one-dimensional (1D) porous channels. We further develop an inner-pore coordination (IPC) strategy to graft bulky phenyl (Ph) and naphthyl (Np) groups on the inner walls of the porous channels. This strategy effectively narrows the intrinsic pore size from ∼2.0 to ∼1.4 nm, which leads to the efficient tailoring of the transmembrane transport toward the high-permeance He separation with high selectivity. Notably, the resultant Por-2DPI-Np COF membrane simultaneously delivers a record-high He permeance of 4323 GPU and a high selectivity of 77.4 (He/CH4), superior to the state-of-the-art reported membranes. The contrast experiments supported by theoretical modeling reveal that the exceptional performance arises from the synergistic effect, where the ultrathin feature and 1D pore arrays ensure high permeance. Meanwhile, the grafted branches impede the diffusion of CH4 more significantly than that of He, resulting in an enhanced molecular sieving effect for high selectivity. Our work provides a general strategy to overcome the permeability-selectivity trade-off and highlights the unprecedented potential of engineered COF membranes for highly efficient helium recovery.

Photocatalytic semi‐hydrogenation of acetylene (C 2 H 2 ) to ethylene (C 2 H 4 ) is seriously limited by the inefficient generation and directional transfer of active hydrogen species. Here, we report a proton‐coupled electron transfer (PCET) mechanism for photocatalytic acetylene semi‐hydrogenation by establishing a hydroxyl network over hydroxyl‐modified carbon nitride (C 3 N 4 ‐OH)/Ni(OH) 2 composite. Such a hydroxyl network not only enhances photogenerated charge separation but also establishes a strong hydrogen‐bonding microenvironment for adsorbing interfacial water and facilitating hydrogen transfer dynamics. Femtosecond transient absorption (fs‐TA) spectroscopy, in situ photochemical infrared spectroscopy, kinetic isotope effect (KIE), and active hydrogen (H*)‐trapping reveal that the fast proton transfer via a PCET mechanism, rather than a conventional hydrogen atom transfer (HAT) pathway. Eventually, the C 3 N 4 ‐Ni(OH) 2 achieves an exceptionally high C 2 H 4 production rate of 15.7 mmol g cat −1 h −1 with a C 2 H 4 selectivity of 98.2% under simulated solar irradiation. For purifying a crude C 2 H 4 stream containing 0.5 vol% C 2 H 2 , the C 2 H 2 conversion remains ∼98% over a long‐term continuous‐flow operation. This work elucidates the pivotal role of surface hydroxyl networks in governing hydrogen kinetics and paves a new avenue for the design of high‐performance photocatalysts.

ABSTRACT Mimicking natural photosynthesis to split water into oxygen and hydrogen represents a promising pathway for transitioning from fossil fuels to a sustainable energy future. It is extremely challenging to duplicate the efficient and elegant oxygen evolution complex of photosynthesis II of oxidizing water to O 2 being regarded as the bottleneck of water splitting. Cutting‐edge artificial molecular water oxidation catalysts (WOCs) with low overpotentials are highly desirable for efficient water oxidation. Here we report the design of a molecular water oxidation catalyst (WOC) RuN5 (Ru(N5)(pic) 2 ; N5 = 4‐tert‐butyl‐2,6‐di(1′,8′‐naphthyrid‐2′‐yl)pyridine, pic = 4‐picoline). Following electrochemical activation and bromide mediation, RuN5 achieves a high turnover frequency of 2604 s −1 with a low overpotential of 363 mV at pH 7. The catalyst is highly stable, maintaining a steady current density of 1.8 mA cm −2 over 200 h. Mechanistic studies reveal that activation and bromide mediation facilitate O–O bond formation via a ligand‐oxidized [Ru IV ═ O] 2+ intermediate through a low energy pathway, distinct from the classical [Ru V (O)] 3+ route. This work opens a new avenue for developing efficient molecular WOCs and advancing artificial photosynthesis.

Photocatalytic semihydrogenation of coal-derived acetylene using water as a hydrogen source under ambient conditions offers a sustainable and petroleum-independent route for ethylene production, yet suffers from the utilization of expensive photosensitizers, weak acetylene adsorption and insufficient generation of active hydrogen (H*). Herein, we fabricate a Co single-atom catalyst anchored on nitrogen-vacancy-rich carbon nitride (Co/C3N4-VN) via in-situ co-polymerization. Owing to enhanced light absorption and charge separation efficiency, the Co/C3N4-VN exhibits a considerably high ethylene production rate of 3916.5 mu molgcat -1h-1 under 420 nm light-emitting diode (LED) illumination without photosensitizers, surpassing bulk C3N4 by 53-folds and outperforming previously reported photocatalysts. The photocatalytic experiments, acetylene temperature-programmed desorption analysis, in-situ photo-chemical infrared spectra and theoretical simulations together reveal that N vacancies and Co single atoms in Co/C3N4-VN synergistically promote the acetylene adsorption, H* generation from water dissociation and acetylene hydrogenation, thereby accelerating the kinetics of photocatalytic acetylene semihydrogenation.

This study systematically optimized the geometric parameters of a Soller slit collimator to enhance X-ray detection performance, focusing on maximizing the photon count at the origin (N0) while minimizing the spatial spread, which is defined by the radial distance where the collection efficiency drops to 50% (R50%). Through four sets of finite element method simulations under fixed detector distance (15 mm) and monochromatic X-ray source conditions, the effects of the slit top position (Htop), number of fins (Nf), fin spacing uniformity, and fin height distribution were investigated. The optimal parameters were identified as Htop = 2 mm, Nf = 21, uniform fin spacing (df = 0.5 mm), and uniform fin height (13 mm). This configuration achieved N0 = 178,257 photons, R50% = 34.5 mu m (X-direction), and R50% = 150 mu m (Z-direction), effectively balancing the inherent trade-off between the photon collection efficiency and spatial resolution. Compared to the optimal design, configurations employing nonuniform spacing and nonflat height distributions degraded spatial resolution by 12%-19%. The optimized design shows significant potential for improving spatial resolution in microfluorescence applications within synchrotron radiation beamlines. Placing the sample surface near R50% can effectively reduce the influence of scattering signals within the bulk material. This can serve as a low-cost alternative for confocal experiments.

Arsenic trioxide (ATO) shows limited efficacy against solid tumours, largely because it induces protective autophagy that attenuates its pro-apoptotic activity. Our previous studies established that nanodiamonds (NDs) function as nanoparticle autophagy inhibitors (NAPIs) when delivered systemically, markedly enhancing ATO efficacy in orthotopic liver tumour models by blocking NUPR1-mediated autolysosomal clearance. However, systemic administration remains inefficient in modulating the local autophagic microenvironment within tumours. Here we developed an interventional strategy based on intratumoral injection to assess the feasibility and biosafety of locally blocking autophagic flux while substantially reducing the required ATO dosage, thereby maximising the synergistic anti-tumour effects of NDs and ATO. In HepG2 hepatocellular carcinoma cells, NDs markedly blocked the late stage of autophagic flux, thereby significantly amplifying ATO-induced apoptosis. In a subcutaneous xenograft liver cancer mouse model, intratumoral co-administration of NDs with low-dose ATO achieved ~91% tumour inhibition and effectively eliminated the systemic toxicity associated with high-dose ATO monotherapy. Notably, the synergistic antitumor effect was independent of increased intratumoral ATO accumulation and was driven instead by targeted modulation of the autophagic pathway. Collectively, this study demonstrates a mechanism of localised, nanomaterial-mediated autophagy regulation and offers an efficient, safe strategy for interventional therapy of advanced solid tumours.

Palladium single-atom catalysts show exceptional catalytic performance in nitrile butadiene rubber (NBR) hydrogenation due to their unique unsaturated coordination environments. However, the hydrogenation activity and atomic efficiency are seriously limited by inherent instability of undercoordinated Pdδ+ sites and poor support structure, leading to decreased hydrogenation degree and cycling stability. In this work, a novel single-atom palladium catalysts was developed, where undercoordinated single-atom Pdδ+ sites are steadily anchored onto CeO2-x nano-islands supported by SiO2 (Pd1/CeO2-x/SiO2). The strong metal-interaction of CeO2-x nano-islands immobilize the undercoordinated Pdδ+ sites to enhance adsorption of olefin bonds in NBR, while SiO2 promotes mass transfer diffusion of NBR and atomic efficiency of palladium. The Pd1/CeO2-x/SiO2 thus achieves an unprecedented hydrogenation degree of up to 99.8% without decrease over a 10-runs stability test in selective hydrogenation of NBR, outperforming previously state-of-the-art catalysts. Consequently, this work will offer a new strategy for single-atom catalysts to achieve high steady-state activity in selective hydrogenation.

The commercial viability of reversible protonic ceramic cells (R-PCCs) is currently hindered by the dichotomy between activity and stability in air electrodes. Conventional oxygen vacancy rich Co perovskite, such as PrBaCo2O6-δ (PBC), offer rapid kinetics but suffer from phase degradation, while its stable counterpart, PrBa0.8Ca0.2Co2O6-δ (PBCC), lack sufficient catalytic efficiency. Here, we demonstrate an entropy-engineering (EE) strategy that reconciles high electrochemical performance with operational stability in PrBa0.8Ca0.2Fe0.4Co0.4Ni0.4Cu0.4Zn0.4O6-δ (EE-PBCC). The EE-PBCC electrode delivers a peak power density of 1210 mW cm−2 at 650 °C and sustains reversible cycling for over 200 h, significantly outperforming both PBC and PBCC benchmarks. The temperature-dependent hard X-ray absorption spectra at the Co-K edge indicate a further increase in oxygen vacancies above room temperature. Density functional theory (DFT) calculations reveal that the high-entropy B-site configuration and oxygen vacancies optimize the electronic structure and oxygen adsorption energy, thereby accelerating ORR kinetics despite a significant reduction in cobalt content. This work provides a generalizable entropy-engineering pathway to design cost-effective, durable, and highly active air electrodes for next-generation R-PCCs.

ABSTRACT Platinum‐based zeolite catalysts are among the most effective systems for propane dehydrogenation (PDH), yet their industrial deployment is limited by their poor regenerability under harsh redox cycling. Here, we report a ligand‐protected strategy to simultaneously encapsulate subnanometric CeO x and Pt clusters within silicalite‐1 (S‐1) zeolite. Zeolite confinement stabilizes both Pt and CeO x species under reducing dehydrogenation conditions, while the dynamic and reversible formation of strong Pt–CeO x interactions facilitates the reversible redispersion of Pt species during oxidative regeneration. Notably, the Pt‐4CeO x @S‐1 catalyst remains fully regenerable after 9 consecutive redox cycles and sustained operation over 5000 min at 600°C. Even after steam treatment at 600°C, the catalyst fully recovers its activity through simple calcination–reduction, demonstrating outstanding structural durability under industrially relevant conditions. Integrated theoretical and experimental evidence shows that confinement within the zeolite framework allows CeO x to dynamically capture mobile PtO x via Pt–O‒Ce bond formation, facilitating atomic‐scale Pt redispersion under oxidative conditions. This work offers a generalizable strategy for constructing redox‐adaptive catalyst architectures with built‐in self‐regeneration, advancing the design of robust zeolite‐based catalysts for high‐temperature and cyclic catalytic processes.

Magnesium hydride (MgH2) is a promising hydrogen storage material for its high hydrogen capacity of 7.6 wt.%. However, the further application is severely hampered by the sluggish reaction kinetics and stable thermodynamics. Introducing catalysts is an effective method to improve the reaction rate, but the catalytic activity tends to decrease with an increasing number of reaction cycles, due to the highly reductive Mg and H species. Herein, the spring effect has been observed in the P doped Li3VO4, in which both V & horbar;P and V & horbar;V bonds undergo compression and elongation during hydrogen absorption and desorption, respectively. Such a unique self-regulation spring effect not only improves the reaction kinetics of MgH2, but also maintains the high activity of P doped Li3VO4, thereby ensuring the hydrogen capacity of MgH2 even after 100 loops. This spring effect of chemical bonding, stretched-recovered-stretched with the motion between the highly reductive Mg and H species, will provide insight into catalyst design for hydrogen-related industries.

A small amount of Mg2+ doping can show a significant effect on the surface protection and structural stability of the nickel-rich layered oxide cathode, but the traditional doping process involves completely changing the initial raw material proportions with subsequent trial and error adjustments. Herein, a concept of Mg2+ release film is proposed, in which Mg2+ can easily permeate into various layered oxide cathodes during cycling. Meanwhile, to realize this concept, MgV2O4 with mobile Mg2+ in the structures and then fabricated a self-supporting MgV2O4 membrane are synthesized. As a protective layer for cathode, the MgV2O4 membrane release Mg2+ in situ during the electrochemical process, providing structural reinforcement to the cathode surface as a "pillar" within the lattice. Thanks to the MgV2O4 membrane, the cycle life of LiNio.8Co0.1Mn0.1O2(NCM811) coupled with the MgV2O4 interlayer at 1.0 C is increased by 1.9 times compared to bare NCM811. Furthermore, this novel Mg2+ releasing film demonstrates excellent versatility, enabling other nickel-based layered oxide to achieve a high-capacity retention of 86.4% after 800 cycles at 1.0 C. This approach provides scalable cathode protection and repair strategies for commercially viable batteries.

Achieving detailed neuronal structural information in large-volume brain tissue has been a longstanding challenge in human brain imaging. A key obstacle arises from the trade-off between staining efficiency and tissue autolysis. Traditional Golgi staining, typically conducted at room temperature or 37 °C to optimize staining efficiency, leads to rapid autolysis of brain tissue, resulting in the loss of fine structural details. Here, a near-freezing temperature (NFT) staining strategy in post-mortem frozen (PMF) human brain samples are presented, using a mercury chloride-based method under ice-water bath conditions. In contrast to the 37 °C Golgi staining, this NFT-based method significantly reduces tissue autolysis, preserving fine neuronal structures. Notably, neuronal counts in the same field of view increased by 5.5-fold, and dendritic spine density increases by 22-fold. Using this approach, uniform staining of millimeter-thick is achieved, centimeter-scale human brain slices and integrated it with synchrotron-based X-ray microscopy to perform micrometer resolution 3D reconstructions of the cerebellum and frontal lobe. This novel technique offers a powerful tool for the fine-structural imaging of large-volume brain tissue, providing new insights into the intricate organization of neural networks.

One primary challenge in whole-brain imaging technology is to achieve high-resolution visualization of neuronal connectivity at large scales. Although the Golgi method allows for labeling random neurons in their entirety, visualizing individual dendritic trees, and tracing long-distance axonal projections, the lengthy processing time poses a limitation, as staining a mouse whole-brain sample of ∼500 mm3 takes over two weeks. Here, we developed a high-pressure-assisted Golgi-Cox (HP Golgi-Cox) method that reduced the staining time for mouse whole-brain neurons from 16 to 4 days. We demonstrated its applicability in zebrafish, mice, and rats, and further achieved rapid staining of hippocampal neurons in an intact pig brain, which is challenging with the classical Golgi-Cox method. By combining the HP Golgi-Cox method with synchrotron-based X-ray microscopy, we achieved high-resolution imaging of whole-brain neurons in mice. This HP Golgi-Cox method enables rapid and high-resolution neuronal imaging in large model organisms, showcasing its broad applicability for diverse applications.

Graphdiynes (GDYs), synthesized via direct coupling of arylacetylenes, have attracted great attention due to their unique electronic properties and structural diversity, typically forming 2D layered frameworks. However, crystalline GDY‐like frameworks with 3D topology remain challenging to synthesize. Here, the study reports two highly crystalline, isomeric GDY‐like frameworks with ThSi2 topology, constructed from 2,2′‐binaphthalene and 6,6′‐biazulene‐based monomers. The azulene‐based framework, due to its large dipole moment, exhibits a narrow bandgap of 1.15 eV, significantly lower than its naphthalene counterpart (2.33 eV). As ruthenium (Ru) single‐atom supports, these frameworks enable strong Ru‐diyne interactions, achieving an ammonia yield rate of 188.7 ± 1.6 µg h −1 mg cat −1 and a Faradaic efficiency of 37.4 ± 0.6%. Such bicontinuous channels and tunable electronic structures offer electrocatalysis field new opportunities. Moreover, the azulene‐based framework, featuring a higher highest occupied molecular orbital and lower lowest unoccupied molecular orbital energy level, ensures superior electron mobility. These 3D crystalline frameworks introduce a new covalent organic framework (COF) family with diyne linkages and pure carbon skeletons, broadening the scope of COF materials. Their well‐defined structures provide an ideal platform for tuning optoelectronic properties, enabling fundamental studies on structure‐property relationships and opening new opportunities for catalytic and electronic applications.

2D metal-organic frameworks (2D MOFs) are emerging organic van der Waals materials with great potential in various applications owing to their structural diversity, and tunable optoelectronic properties. So far, most reported 2D MOFs rely on metal-heteroatom coordination (e.g., metal-nitrogen, metal-oxygen, and metal-sulfur); synthesis of metal-carbon coordination based 2D MOFs remains a formidable challenge. This study reports the rhodium-carbon (Rh-C) coordination-based 2D MOFs, using isocyanide as the ligand and Rh(I) as metal node. The synthesized MOFs show excellent crystallinity with quasi-square lattice networks. These MOFs show ultra-narrow bandgaps (0.1-0.28 eV) resulting from the interaction between Rh(I) and isocyano groups. Terahertz spectroscopy demonstrates exceptional short-range charge mobilities up to 560 ± 46 cm2 V-1 s-1 in the as-synthesized MOFs. Moreover, these MOFs are used as electrocatalysts for nitrogen reduction reaction and show an excellent NH3 yield rate of 56.0 ± 1.5 µg h-1 mgcat -1 and a record Faradaic efficiency of 87.1 ± 1.8%. In situ experiments reveal dual pathways involving Rh(I) during the catalytic process. This work represents a pioneering step toward 2D MOFs based on metal-carbon coordination and paves the way for novel reticular materials with ultra-high carrier mobility and for versatile optoelectronic devices.

Achieving high product selectivity at ampere-level current densities is essential for the industrial application of electrochemical CO 2 reduction. However, the operational stability of CO 2 electrolyzers at large current density has long been hindered by flooding of gas diffusion layer (GDL). Herein, a new heteroarchitectural GDL is designed to overcome flooding. Such GDL is constructed by sequentially sputtering the conductive silver and titanium boride (TiB 2 ) onto a polytetrafluoroethylene substrate. Assembled with Cu catalyst in a flow cell, a maximum ethylene Faradaic efficiency of 64.7 % was achieved at a current density of 1.2 A cm −2 in 6 M KOH. Furthermore, the GDL is capable of stable operation for over 40 hours at 400 mA cm −2 . Theoretical calculations and in situ experiments demonstrate enhanced intermediates adsorption on the TiB 2 -supported Cu surface, thereby reducing the energy barrier for C−C coupling. When coupling the CO 2 reduction reaction with 5-hydroxymethylfurfural oxidation reaction, Faradaic efficiencies of 49.2 % for ethylene and 85.4 % for 2,5-furandicarboxylic acid were achieved at 1.2 A cm −2 . This work provides a highly stable GDL for efficient CO 2 conversion at ampere-level current density and paves the way for integrating biomolecules conversion in stack-level devices.

Understanding the structural and functional organisation of brain networks is a fundamental objective in neuroscience, with three-dimensional (3D) reconstruction of single-neuron morphology serving as a critical foundation. The Golgi staining method, which enables random neuronal labeling and provides high-contrast signals in both optical and X-ray microscopy, remains a valuable tool for morphological analysis. However, its widespread application in large-scale neuronal reconstructions is hindered by signal discontinuities in neuronal branches, high-density labeling, and complex background interference. While automated reconstruction methods perform well in sparsely labelled and morphologically simple neuronal populations, their effectiveness is limited in Golgi-stained samples. Here we develop a semi-automated single-neuron reconstruction method for Golgi-stained mouse brain neurons (SNR-Golgi). By integrating three key technical modules-background denoising, single-neuron extraction, and branch repair-SNR-Golgi significantly enhances the accuracy and completeness of neuronal reconstruction. In fluorescence micro-optical sectioning tomography (fMOST) datasets, SNR-Golgi demonstrated superior performance in neuronal reconstruction within the mouse somatosensory cortex, achieving a 30% increase in reconstructed branch count, a 76% improvement in total branch length, and a 3.7-fold increase in axonal length. Additionally, in synchrotron-based X-ray imaging datasets, SNR-Golgi enabled submicron-resolution 3D reconstruction of single neurons. These results demonstrate that SNR-Golgi effectively addresses the complexity of Golgi-stained samples and provides robust technical support for the structural analysis of brain neurons across various imaging modalities.

Selective thermocatalytic hydrogenation of 2-butyne-1,4-diol (BYD) to 2-butene-1,4-diol (BED) is vital for producing downstream fine chemicals like pharmaceuticals. However, the current thermocatalytic semihydrogenation typically requires elevated temperatures, excessive high-pressure H2, and costly Pd-based catalysts or flammable Raney Ni. Here, we highlight a sustainable photocatalytic semihydrogenation of BYD to BED using Cu single atoms anchored on TiO2 nanoparticles (Cu-SAs-TiO2) with water as the hydrogen source under ambient conditions. Under the irradiation of simulated solar light, Cu-SAs-TiO2 unprecedentedly achieves a BYD conversion of similar to 100% with an exceptionally high BED selectivity of 99.4%, which substantially outperforms the previously reported thermocatalysts. Even in a large-scale photocatalytic system (6 L) and under outdoor sunlight irradiation of 22 h, Cu-SAs-TiO2 still delivered a BYD conversion of similar to 100%, a BED selectivity of 97.5%, and a BED production rate of 0.22 mmolBEDgcat -1h-1. Isotope-labeling analyses, experiments on the kinetic isotope effect of hydrogen, in situ photochemical infrared spectra, and theoretical simulations together reveal that the Cu single atoms promote water dissociation and BED desorption, eventually contributing to a complete BYD conversion and a high BED selectivity.

With the construction and operational launch of third-generation synchrotron radiation sources, X-ray molecular probe technology is actively explored and developed, playing an increasingly significant role in modern life sciences. This review provides an overview of synchrotron-based X-ray imaging techniques and emphasizes the applications of X-ray molecular probes across various fields associated with intelligent biomedicine. Building on this foundation, it further discusses future advancements in X-ray molecular probes and forecasts their application trends in intelligent biomedicine, particularly in the realm of personalized treatment.