The amide moiety is unarguable importance due to its widespread presence in numerous biologically active molecules, including agrochemicals, insecticides, pharmaceutical agents, peptides, proteins, polysaccharides and nucleic acids. The condensation of a carboxylic acid and an amine using a coupling reagent or metal/boronic catalyst represents the most common approach in amide synthesis and is frequently employed in producing modern pharmaceuticals. However, the use of stoichiometric amounts of coupling agents, oxidants, or catalytic amounts of metal catalysts often involves challenges such as toxicity and high cost. In connection with our studies on photoredox acylations, we herein report an efficient photoredox dealkylative acylation of tertiary amines with acid anhydrides using a commercially available and inexpensive acridine salt-based photocatalyst, which enables the preparation of a wide range of amides from tertiary amines under mild reaction conditions. To an oven dried Schlenk-tube, benzoic anhydride (45.2 mg, 0.20 mmol), triethylamine (60.7 mg, 0.60 mmol), $\mathrm{Mes}-\mathrm{Acr}^{+} \mathrm{ClO}_{4}^{-}$ (1.6 mg, 0.004 mmol) and MeCN (2 mL) were added under argon atmosphere. The reaction mixture was stirred under the irradiation of 20 W Blue LED (450 nm) at room temperature. After completion of the reaction, the reaction mixture was concentrated by vacuum, purified by silica gel chromatography, and eluted by petroleum ether/ethyl acetate to obtain products. With the optimized reaction conditions in hand, we investigated the scope of anhydrides and tertiary amines in the present dealkylative acylation. In general, all tested substrates were suitable for yielding amidation products, all of the aliphatic, aromatic anhydrides and tertiary amines are suitable reactants for the transformations to afford the corresponding amides in moderate to excellent yields. The successful gram-scale reaction and late-stage functionalization of drug molecule in mild conditions under room temperature have qualified the protocol to be practical, cost-effective, and environmentally friendly. The mechanistic studies have verified the single-electron oxidation of tertiary amine by the photosensitiser and the generation of an acyl radical via single electron reduction of anhydride.

Aqueous organic redox flow batteries (AORFBs), recognized as a promising large-scale energy storage technology due to their high efficiency, inherent safety, and tunable performance characteristics, have garnered significant research interest in recent years. This review systematically summarizes recent advances in positive redox-active materials for AORFBs, with a focused analysis of representative organic electroactive species, including ferrocene derivatives, ferrocyanides/iron-based complexes, nitroxide radicals, quinones, and phenothiazine-based compounds. Through molecular engineering strategies such as functional group modification, conjugation extension, and electronic structure modulation, critical properties of organic active materials, including redox potentials, solubility in aqueous electrolytes, and chemical and electrochemical stability, have been substantially enhanced, leading to marked improvements in battery performance metrics. Despite these advancements, the practical deployment of organic positive materials continues to face challenges related to long-term cycling stability under operational conditions, limited energy density, and cost-effectiveness in scalable synthesis and processing, requiring further research and solutions.

Non-covalent molecular capsules stand as a central research theme in the field of supramolecular chemistry. Characterized by their dynamic confined architectures assembled through non-covalent interactions, including hydrogen bonding and electrostatic interaction, these capsules hold significant promise for applications in catalysis, medicine, and materials science. Conventionally, the construction of molecular capsules has predominantly depended on pre-embedded complementary motifs within supramolecular hosts, a limitation that restricts their synthetic versatility and adaptability. This study addresses this challenge by presenting the design and synthesis of a water-soluble 2-aminobenzimidazole-functional- ized cavitand 1, which is based on a resorcin[4]arene framework. And we examined the binding of the homologous series of the n-alkanes (n-C₇H₁₆ to n-C₂₀H₄₂) to cavitand 1 using a combination of ¹H NMR spectroscopy (nuclear magnetic resonance spectroscopy), 2D NOESY (two-dimensional Nuclear Overhauser Effect Spectroscopy) and DOSY (diffusion ordered spectroscopy) experiments. Cavitand 1 can form 1∶1 complexes with n-C₇H₁₆ and n-C₁₀H₂₂, and no encapsulation behavior for n-C₁₁H₂₄ because the size of n-C₁₁H₂₄ is too large to form 1∶1 complex and too small to form a dimeric capsule. n-C₁₂H₂₆ to n-C₂₀H₄₂ are good templates for the formation of 1∶2 guest-host capsular complexes. The guest of n-C₁₂H₂₆ fits the space comfortably in an extended conformation and broadened, symmetrical signal patterns were observed in the ¹H NMR spectrum. For n-C₁₅H₃₂ the signals are sharper suggesting a kinetically more stable complex. The conformation of n-C₁₅H₃₂ inside the capsule was determined by 2D NOESY experiments. Cross-peaks between the hydrogen atoms at C(1) and C(3) and at C(1) and C(4), C(2) and C(4) and at C(2) and C(5) were observed. But C(6) is in NOE contact only with C(8). This demonstrates the presence of gauche conformations of four carbon atoms at the ends and an extended chain of carbon atoms in the middle. n-C₇H₁₆⊂1 is a 1∶1 complex and n-C₁₅H₃₂⊂1.1 is a dimeric capsule confirmed by DOSY experiments which reveal diffusion coefficients for n-C₇H₁₆⊂1 (D=2.02×10⁻⁶ cm²•s⁻¹) and n-C₁₅H₃₂⊂1.1 (D=1.54×10⁻⁶ cm²•s⁻¹). Through the Stokes-Einstein relationship, show that the hydrodynamic volume of n-C₁₅H₃₂⊂1.1 is 2.3 times that of n-C₇H₁₆⊂1. Then we investigated host-guest interactions between cavitand 1 and styrylpyridinium SP-Cn (n=1~10) fluorophores in solution using ¹H NMR and UV-Vis absorption spectra. The results indicate that a supramolecular nano-capsule structure was formed with a 2∶1 host-guest stoichiometric ratio (SP-Cn⊂1.1). The electron-poor pyridinium group of SP-Cn is bound within the electron-rich cavity through cation…π interactions. Hydrophobic effects and C—H…π hydrogen bonds drive two cavitand 1 to form a capsule. And the alkyl chain of SP-C10 was compressed to J-shaped conformation by the restricted space. SP-C1⊂1.1 exhibits strong fluorescence in water due to the suppression of aromatic ring rotation within the confined space. Overall, the formation of these molecular capsules is primarily driven by the synergistic action of hydrophobic interactions and C—H…π interactions, providing new insights into the rational design of supramolecular assemblies.

Doping heteroatoms (B, N, O, S, P) into polycyclic aromatic hydrocarbons (PAHs) has been developed as an efficient strategy to achieve intriguing electronic structures and optoelectronic properties. In particular, boron-containing nonbenzenoid PAHs are a class of conjugated polycyclic π systems that combine the boron atoms and nonbenzenoid motifs, such as pentagon and heptagon rings. These molecules not only possess wonderful topological structures, but also have electronic structures and physicochemical properties that are obviously different from those of traditional carbon-based PAHs. Owing to these characteristics, they have exhibited great potential applications in optoelectronic devices, including organic light-emitting diodes (OLEDs) and organic field-effect transistors (OFETs). However, the high reactivity and sensitivity of boron atoms to moisture and oxygen leads to severe limitations in design and synthetic methods, and difficulty in construction of boron-containing π-systems. Thus, following the design strategies for enhancing the stability of the boron atom by introducing bulky substituents or utilizing structural constraint and the efficient synthetic approaches, a series of boron-containing nonbenzenoid PAHs, including boron/nitrogen-type, boron/oxygen-type, boron/sulfur-type and pristine boron-doped systems, have been dramatically developed. These molecules not only possess intriguing topological structures and excellent stability, but also exhibit fascinating optoelectronic properties, such as thermally activated delayed fluorescence, reversible redox capabilities and magnetic properties. Moreover, they exhibit sufficient Lewis acidity, enabling them to coordinate with Lewis bases to form Lewis acid-base adducts, thus achieving stimuli-responsive functions. Therefore, the precise introduction of boron atoms into polycyclic structures to construct boron-containing nonbenzenoid PAH systems and fine modulation of physical properties and functions has become the key topic in the research fields of PAHs, organoborane chemistry and organic functional materials. In this review, we aim to highlight the design and synthetic strategies of boron-containing nonbenzenoid PAHs, along with their intriguing electronic structures, physical properties and practical applications. Additionally, the synthesis challenges and future development opportunities of these molecules are analyzed and prospected.

Polyhydroxyalkanoates (PHAs) are a class of biodegradable materials produced by bacterial fermentation. They are considered as potential alternatives for traditional plastics because their material properties are comparable to those of commercial polyolefins. However, the high cost of fermentation production has seriously restricted their large-scale application. Although PHAs produced by natural bacterial fermentation show rich structural diversity, the products are mostly limited to alkyl side-substituted derivatives and are mainly used as thermoplastics. Consequently, the development of cost-effective and efficient chemical synthesis routes to produce PHAs with enhanced structural diversity and broader potential applications is of considerable importance. In this study, functionalized four-membered cyclic lactone monomers, BPL^CH2OR (R=Bu, Bn), substituted with alkoxy and benzyloxy groups, were synthesized via carbonylation of commercially available epoxides with carbon monoxide. These monomers undergo stereoselective ring-opening polymerization (ROP) to yield polymers with structures distinct from those of natural PHAs. A stereoselective polymerization system for rac- BPL^CH2OR was developed using a spiro-salen yttrium complex Y2 as the catalyst. The resulting PHAs with high syndiotacticity (P_r>0.95) exhibit significant differences in stereoregularity and thermal performance compared to their natural counterparts. It was observed that rac-Y2 and its corresponding chiral (R)-Y2 exhibit distinct catalytic behaviors: while both catalysts enable good molecular weight control, producing P(BPL^CH2OR) with low dispersity (Đ<1.15), polymerization catalyzed by (R)-Y2 yielded atactic P(BPL^CH2OR) in the form of oily liquids, whereas rac-Y2-catalyzed polymerization produced semicrystalline syndiotactic P(BPL^CH2OR) (P_r>0.95). The glass transition temperatures (T_g) and melting temperatures (T_m) range from －61 ℃ to 74 ℃. P(BPL^CH2OBn) illustrates potential for post-polymerization modification. Upon debenzylation, it is expected to generate hydrophilic, stereoregular and biodegradable materials, thus demonstrating promising application prospects in the biomedical field.

With the intensification of environmental challenges and the ever-growing global energy demand, conventional materials are increasingly unable to satisfy the stringent requirements in energy and environmental fields. Metal-organic frameworks (MOFs), as a class of crystalline porous materials composed of metal nodes and organic ligands, have emerged as promising candidates due to their tunable pore structures, exceptionally high surface areas, and versatile functionalities. These features enable MOFs to play a significant role in applications such as adsorption and electrochemical energy storage. However, the poor intrinsic electrical conductivity and limited structural stability of pristine MOFs restrict their practical implementation. To address these limitations, MOF-based composites have been developed by integrating MOFs with a variety of guest materials including inorganic carbonaceous materials (e.g., graphene, carbon nanotubes), metal oxides, and conductive polymers. These composites not only retain the inherent advantages of MOFs but also enhance conductivity, mechanical robustness, and chemical stability through synergistic interactions. Importantly, the integration strategies often involve the construction of heterostructures, interface engineering, and the introduction of chemically bonded interfaces, thereby promoting efficient charge transfer and long-term cycling stability. Herein, a comprehensive summary of MOF composites and their emerging applications in electrochemical energy storage systems, such as supercapacitors, lithium-ion batteries, lithium-sulfur batteries and aqueous zinc ion batteries, as well as in environmental adsorption processes targeting heavy metals and CO₂ capture, is offered. The discussion also emphasizes dimensional design from zero-dimensional (0D) nanoparticles to three-dimensional (3D) frameworks, each exhibiting unique advantages in terms of electron transport, ion diffusion, and active site accessibility. The relationships of these composites are analyzed, highlighting how different combinations and morphologies (e.g., core-shell architectures, layered hybrids, and flexible films) influence their functional performance. MOF composites represent a promising frontier for the development of next-generation functional materials. Their tunable dimensionality, enhanced chemical properties and multifunctional adaptability open up new avenues for solving urgent global issues in energy sustainability and environmental remediation.

Polyolefin materials occupy an important position in the national economy as indispensable basic materials for modern industry and daily life, representing the most extensively produced synthetic polymer materials globally. Transition metal catalysts are the significant driving factors for the development of the polyolefin industry, among which single-site non-metallocene transition metal catalysts have received widespread attention due to their simple synthesis and efficient linear polyolefin stereocontrol ability. Meanwhile, 1-butene, as a crucial byproduct of petrochemical industry, presents substantial research value for its high-value utilization. For example, current industrial circle employs heterogeneous Ziegler-Natta catalyst systems to produce isotactic poly(1-butene), which has found extensive applications in engineering fields such as hot water pipes. However, no other isotactic (mmmm<90%) poly(1-butene) materials have been reported for commercial applications. Based on the above background, we employed tridentate titanium complexes with quinoline side-arms to achieve efficient production of non-isotactic poly(1-butene) with good activity (over 10 kg•mmol⁻¹•h⁻¹), high M_n (up to 1800 kDa) and isotacticity of around 80% mmmm. Detailed methodological research (reaction temperature, catalyst concentration, etc.) was utilized to optimize polymerization activity and search for the rules of reaction conditions and results. Additionally, this work also achieved efficient copolymerization of 1-butene and 1-hexene with controllable monomer ratios. Both the resulting polymers and copolymers exhibited good material toughness. The breaking stress was close to 40 MPa and the elongation at break exceeded 800%. Wide-angle X-ray diffraction (WAXD) analysis showed that the crystal form of these polymers was form I or form I' without the transformation observed during the aging time, indicating superior stability compared to isotactic poly(1-butene) produced by Ziegler-Natta catalysts. When used as a filler, the obtained poly(1-butene)s significantly enhanced the toughness of natural rubber, demonstrating promising potential for rubber industry applications.

Carbenes (R₂C:) represent a unique class of neutral divalent carbon species that formally possess six valence electrons at the central carbon atom, thereby deviating from the octet rule. These species have long occupied a central role in organic, organometallic, and materials chemistry owing to their rich electronic structures and versatile reactivity. The vast majority of isolated stable carbenes adopt a singlet ground-state electronic configuration described as σ²π⁰, wherein a lone pair occupies an in-plane σ orbital and the out-of-plane π orbital remains unoccupied. This configuration underpins the pronounced nucleophilicity observed in classical N-heterocyclic carbenes and their analogs. A limited number of carbenes with a σ¹π¹ open-shell ground state have been spectroscopically characterized, often exhibiting radical-like behavior and enhanced reactivity. In sharp contrast, carbenes with an inverted electronic configuration—σ⁰π²—remain extraordinarily rare and conceptually intriguing. These carbenes possess two electrons fully occupying the out-of-plane π orbital, leaving the in-plane σ orbital vacant. Such a configuration inverts the typical orbital occupancy pattern, potentially leading to electrophilic or ambiphilic reactivity profiles. To date, four principal design strategies have been proposed to stabilize σ⁰π² carbenes: (1) cyclic di(imino)carbenes; (2) di(boryl)carbene; (3) metal-coordinated cyclic di(phosphino)carbenes; and (4) dicationic carbones. However, despite extensive conceptual exploration, only one stable and isolable σ⁰π² carbene has been structurally authenticated to date. This species features a rigid RhP₂C four-membered metallacycle, wherein the carbene carbon exhibits an unprecedented ¹³C NMR chemical shift below －30 parts per million, representing the most upfield resonance recorded for a carbene center. This carbene demonstrates divergent reactivity patterns uncharacteristic of classical σ²π⁰ congeners. It reacts with both Lewis acids and Lewis bases to yield coordination adducts and π-complexes, respectively, and participates in bond-forming processes such as ketenimine generation from isocyanides. Its demonstrated ambiphilicity offers promise for the activation of inert small molecules, including dinitrogen (N₂)—a long-standing goal in main group chemistry. This perspective provides a systematic overview of the emerging chemistry of σ⁰π² carbenes, critically analyzing structural parameters, stabilization frameworks, and reactivity paradigms. We further highlight the prospective roles of such carbenes in bond activation and novel ligand design, envisioning their integration into next-generation main-group and transition-metal cooperative systems.

Ethylene (C₂H₄) serves as a core raw material in the modern chemical industry, where its efficient separation and purification are of paramount importance. Compared to traditional distillation technology, adsorption separation technology offers significant advantages, including reduced energy consumption, lower costs, and simpler operational procedures. Ethane (C₂H₆)-selective adsorbents can directly obtain high-purity C₂H₄ through a single-step adsorption, simplifying the separation process and reducing energy consumption. Developing efficient C₂H₄ separation and purification technologies is a major demand for energy conservation, consumption reduction and green development in the chemical industry. The key to this research lies in the design and preparation of high-performance C₂H₆-selective adsorbents. The advent of Metal-organic framework (MOF), characterized by their high designability and adjustability, has significantly advanced the research and development of C₂H₆-selective adsorbents. By strategically designing active sites and precisely controlling pore environments, a diverse range of C₂H₆-selective adsorbents have been continuously developed. However, when facing actual separation systems and complex industrial application scenarios, the performance of these materials still needs to be improved, and there is an urgent need for further systematic research on the structure-activity relationship of the C₂H₆ adsorption mechanism. This study provides a comprehensive review of the research progress in C₂H₆-selective adsorbents over the past 15 years, delving into their structural design methodologies, such as flexible gate-opening effects, metal site modifications, and surface potential regulation. It also elaborates in detail on the influence mechanisms of different methods on the adsorption selectivity and capacity. In addition, it emphasizes the key challenges that C₂H₆-adsorbents must overcome in the face of industrial applications, including cyclic stability, green large-scale synthesis, and the establishment of new separation processes. It is expected to lay a theoretical foundation for the precise construction and separation application of high-performance C₂H₆-adsorbents, and to promote the technological innovation and transformative development of the olefin separation industry.

The development of efficient and general strategies for the construction of polycyclic architectures remains a significant challenge in medicinal chemistry and organic synthesis. In this work, a tandem α-C—H oxidation/polyene cyclization of acyclic ethers that enables the efficient synthesis of a series of fused oxatricyclic 6/6/6 ring systems is developed. This strategy proceeds via the in situ generated highly reactive oxonium ion intermediate, which is selectively intercepted through intramolecular trapping, allowing for the rapid conversion of simple linear ether precursors into complex polycyclic frameworks. Systematic optimization of reaction conditions revealed that the transformation proceeded under mild conditions with broad substrates scope and excellent functional groups tolerance. Under an argon atmosphere, polyenyl acyclic ethers 1 (1.0 equiv.), zinc bromide (10 mol%), T^＋BF₄⁻ (2.0 equiv.) and 4Å activated molecular sieve were added to a reaction tube. Subsequently, 1.0 mL of anhydrous 1,2-dichloroethane (DCE) was added as the solvent. The reaction mixture was heated in an oil bath at 70 ℃ for 4 h. Upon completion, the reaction was quenched with saturated aqueous sodium thiosulfate. Then the mixture was extracted with dichloromethane. The organic layers were combined and concentrated under reduced pressure to afford the crude product. The residue was purified by silica gel column chromatography to obtain the cyclized fused oxa-6/6/6-tricyclic architectures 2. Under the optimized conditions, the effects of the ether α-site substituent and terminating aromatic group on the tandem cyclization process were systematically investigated. Remarkably, all substrates underwent efficient cyclization to furnish tricyclic frameworks containing three contiguous stereocenters, achieving yields ranging from moderate to excellent. Notably, the reaction maintained outstanding stereoselectivity, delivering dr>20∶1 in every case examined. According to the proposed mechanism, the specific conformation and the configuration of alkene of key intermediates, combined with the defined geometry of the polyene moiety, induce a highly stereospecific intramolecular cyclization, thereby achieving the efficient diastereoselectivities.

DNA-encoded library (DEL) technology has emerged as an important platform for drug development. It has attracted widespread attention from industry and academia due to its advantages such as short synthesis cycle, simple operation, high throughput and low cost. However, the advancement of DEL technology still faces challenges, such as the lack of DNA-compatible chemical reactions for constructing drug-like privileged scaffolds in DELs. Thiohydantoin is an important nitrogen-containing heterocycle widely present in natural products, bioactive molecules, and marketed drugs (e.g., enzalutamide and apalutamide). Among thiohydantoin compounds, the 5-arylidene thiohydantoin derivatives, which have demonstrated a wide range of biological effects, have attracted much attention. Additionally, aldehydes, as widely available building blocks, offer new synthetic approaches for expanding the chemical space of such thiohydantoin-focused DELs. Based on this, we aimed to develop a method for the efficient synthesis of 5-arylidene thiohydantoin DELs under DNA-compatible conditions. The method involves the Knoevenagel reaction between DNA-conjugated thiohydantoins and aldehydes. First, we optimized the reaction conditions and identified the optimal parameters: DNA-conjugated thiohydantoin (200 pmol, 100 µmol/L in water), aldehyde (2500 nmol, 500 mmol/L in dimethyl sulfoxide (DMSO)), pyrrolidine (400 nmol, 200 mmol/L in DMSO), total reaction volume of 20 μL, organic-to-aqueous phase volume ratio of 1∶1, reaction temperature of 60 ℃, and reaction time of 1 h. Subsequently, we evaluated the substrate scope using different aldehydes and DNA-conjugated thiohydantoins. The results demonstrated a broad substrate tolerance, with most reactions achieving moderate to excellent conversions (50%~98%). This study supports the practical construction of DELs focused on the drug-like 5-arylidene thiohydantoin scaffold and expands the accessible chemical space of DELs.

Polyimide (PI) films are widely used in semiconductor packaging due to their excellent properties, including low dielectric constant, high temperature resistance, and enhanced thermal and chemical stability. In recent decades, the development of modern nanotechnology has led to devices being downsized to the nanoscale, and packaging these nanodevices would require ultrathin films of PI. Understanding the thermal transition and molecular relaxation of the PI ultrathin films is essential for high-quality microelectronic packaging. Although the dynamics of bulk PI have been extensively studied using techniques such as broadband dielectric spectroscopy (BDS) and dynamic mechanical analysis (DMA), the impact of reduced film thickness on these dynamics remains unclear. In this study, we used temperature-variable spectroscopic ellipsometry to examine the thermal expansion and molecular relaxation of PI films as thin as 6 nm, and concurrently, the bulk dynamics of PI were investigated using BDS and DMA for comparison purposes. The PI films were prepared by the heat imidization of poly(amide acid) films, which were polymerized using biphenyltetracarboxylic diandhydride (BPDA) and 4,4'-oxydianiline (ODA). In 300-nm-thick films, we observed the α-relaxation arising from the segmental cooperative rearrangement, and the β-relaxation originating from phenyl ring motion at approximately 260 ℃ (T_α) and 99 ℃ (T_β), respectively. As the film thickness decreased below 100 nm, T_α decreased. Specifically, T_α decreased by 30 ℃ for 6-nm PI films. In contrast, T_β remains unchanged in the ultrathin films, indicating a thickness-independent β-relaxation. Furthermore, the coefficients of thermal expansion increased remarkably with a reduction in film thickness across various temperature ranges (i.e., T<T_β, T_β<T<T_α, and T>T_α), indicating that ultrathin PI films are more sensitive to temperature variations than bulk samples. Such observation of the thickness-dependent thermal expansivity and T_α of ultrathin PI films provide a deep understanding of the effects of nanoconfinement on the dynamics of polymers with rigid chain backbones, which is also meaningful for designing and fabricating stable nano-devices based on ultrathin PI films.

RNA modifications play a pivotal role in regulating gene expression and maintaining cellular homeostasis. While modifications such as N⁶-methyladenosine (m⁶A) and 5-methylcytosine (m⁵C) have been extensively studied, 5-methyluridine (m⁵U) remains relatively understudied despite its abundance and evolutionary conservation, particularly in tRNA. In recent years, despite its low abundance, m⁵U has also been found on mRNA in mammalian cells through high resolution mass spectrometry and metabolic incorporation sequencing method. However, due to the lack of high-throughput sequencing methods, the distribution and biological functions of m⁵U modification on mRNA are still remaining unknown. Various species employ diverse enzymes and traverse two distinct pathways to form m⁵U on tRNA, underscoring the significance and diversity of m⁵U modification throughout evolutionary history. The m⁵U modification on tRNA has also been shown to play a key role in promoting tRNA folding, enhancing tRNA stability, regulating tRNA modification landscape, ribosome translocation, and cellular fitness. The human tRNA methyltransferase TRMT2A, beyond its catalytic role, influences translation fidelity and cell cycle, with implications in cancer and neurodegeneration. Despite some advancements in the study of m⁵U, several challenges persist. For instance, the dynamic regulation mechanism underlying m⁵U modification remains unclear. The precise role of m⁵U in the onset and progression of diseases is still not fully understood, and its potential worth in clinical diagnosis and treatment awaits further exploration. Integrating cutting-edge technologies and multi-omics approaches will be essential to unravel m⁵U's full biological and biomedical potential, offering new insights into RNA epigenetics and disease mechanisms. This perspective highlights recent progress in the study of m⁵U, including its discovery on mRNA, catalytic enzymes, cross-talk with other modifications, and regulatory functions. We also discuss the emerging links between m⁵U and human diseases, and outline the current challenges and future directions in decoding the dynamic regulation and biomedical significance of this RNA modification.

The ultimate goal of catalysis research is to enhance catalytic efficiency under industrial conditions. Industrial catalysts are typically complex multicomponent systems, comprising zeolitic components integrated with non-zeolitic components such as silica, alumina, amorphous aluminosilicate, clay, etc. Their catalytic performance is not only determined by the intrinsic properties of each component, but also is strongly influenced by the nature and extent of intercomponent interactions. However, most academic studies have focused primarily on tailoring zeolitic components, while the critical roles of non-zeolitic components and their interactions with zeolitic components were overlooked. This oversight has contributed to a persistent gap between laboratory research and practical industrial catalyst design. This review focuses on the structural integration and functional synergy between zeolitic and non-zeolitic components in industrial catalysts, with particular emphasis on fluid catalytic cracking systems as a representative case. We discuss the hierarchical and cooperative behavior of multicomponent catalytic architectures and highlight three key types of zeolitic and non-zeolitic components interactions: (1) aluminum species migration and redistribution and its influence on Brønsted and Lewis acidity; (2) cation exchange and proximity-induced modulation of acid sites between components; and (3) pore network matching and interconnectivity, which critically influence molecular diffusion and transport efficiency. By establishing correlations of structure-property-reactivity between the interface of zeolitic and non-zeolitic components, this review provides a conceptual framework to better understand and control these complex systems. We further propose future directions for the rational design of integrated industrial catalysts, emphasizing the use of advanced characterization techniques and computational simulations to unravel microscopic interaction mechanisms. These insights are expected to guide the development of more efficient, energy-saving, and environmentally benign catalytic materials for industrial applications.

The rapid and selective assembly of complex and high-value structures from fundamental starting materials remains one of the most important goals in organic chemistry. The carbonylative 1,2-difunctionalization of olefins is of great attraction since it can simultaneously install a synthetically significant carbonyl group and another functional group across C=C double bonds, providing a straightforward and efficient method for the formation of high-value β-functionalized carbonyl compounds. Compared with alkenes, dearomative carbonylative 1,2-difunctionalization of arenes is much less studied even though this reaction would not only introduce two important functional groups but also convert flat arenes into three-dimensional architectures of increasing interest in medicinal chemistry. The big challenges of this reaction arise from breaking aromatic resonance stabilization and selectivity issues. Herein, we describe a novel dearomative 1,2-allylation/aminocarbonylation of chromium-bound arenes, which enabled rapid and selective incorporation of an allyl group and an amide group into arene π-systems to produce a wide range of β-allylated amide compounds containing 1,3-cyclohexadiene rings. The η⁶-coordination using Cr(CO)₃ unit not only activated the inert benzene π-bond towards dearomatization but also offered the CO source for the carbonylation process. The synthetic potential and the practicability of this method were well demonstrated by the CO-gas-free reaction conditions, the broad substrate scope, and the excellent functional group tolerance. A general procedure for this dearomative 1,2-allylation/aminocarbonylation reaction is depicted as follows: under N₂ atmosphere, allyltrimethylsilane (0.40 mmol, 2.0 equiv.) was slowly added to a solution of (η⁶-arene)Cr(CO)₃ (0.20 mmol, 1.0 equiv.) and Me₄NF (0.60 mmol, 3.0 equiv.) in tetrahydrofuran (THF) (2.0 mL) at 0 ℃. The reaction mixture was stirred at 0 ℃ for 4 h, then cooled to －45 ℃, followed by the addition of N-chloroamine (0.80 mmol, 4.0 equiv.). The reaction mixture was allowed to warm to 30 ℃ gradually within 20 min and stirred at 30 ℃ for another 10 h. The solvent was evaporated in vacuo and the crude mixture was purified by preparative thin-layer chromatography (TLC) to yield the corresponding dearomative allylation/aminocarbonylation product.

Polymer materials play a crucial role in modern industry and technology due to their versatile properties and broad range of applications. However, conventional industrial modification strategies often suffer from an inherent inability to finely tune the balance between strength and toughness, thereby constraining their utility in high-performance applications. To address this challenge, researchers have focused on optimizing the internal structure of polymers as a means to regulate their macroscopic mechanical behavior. Among various strategies, network structure design has emerged as a particularly effective approach. This review takes network structure as a central theme and categorizes the mechanisms of polymer modification based on their energy dissipation pathways. Six major mechanisms are discussed: hydrogen bonding, coordination interactions, host-guest interactions, force-sensitive groups, mechanically interlocked structures, and other reinforcing effects. For each category, we provide overview of recent representative and innovative studies. Through detailed structural analysis and performance evaluation, we highlight how different pathways contribute to the enhancement of mechanical properties. These special structures markedly enhance the material's ability to dissipate energy upon external force. This improvement arises primarily through three synergistic pathways: (1) the reversible breaking and reformation of sacrificial bonds, which serve to absorb and redistribute applied stress; (2) energy dissipation via molecular mobility and chain segmental friction; and (3) multiscale mechanisms of stress transfer and dispersion, which effectively mitigate stress concentration and delay failure. Finally, based on the current research, we identify key unresolved questions and major challenges that must be addressed to further advance the mechanical performance of polymer materials. Looking ahead, the development of next-generation high-performance polymers is expected to converge on several critical directions: achieving sustainability in material sourcing and processing, the combination of high elasticity and high toughness, reducing economic costs, and deepening the multiscale understanding of structure-property relationships. These avenues will be pivotal in guiding the rational design of polymer systems for future technological demands.

Proximity-dependent nucleic acid self-assembly technology has emerged as an innovative approach for ultrasensitive detection and dynamic analysis of protein-protein interactions (PPIs) by converting transient PPI events into programmable nucleic acid sequence. This technology integrates signal amplification strategies with versatile readout modalities to achieve high-resolution PPI characterization. In this review, the working mechanisms of proximity-dependent nucleic acid assembly in PPI studies are systematically elucidated. First, the fundamental principle of proximity-induced local enrichment of probes is emphasized, which drives sequence-specific nucleic acid hybridization and self-assembly. Subsequently, nucleic acid signal amplification strategies, such as rolling circle amplification, are elaborated. Furthermore, conventional fluorescence detection and next-generation sequencing-based digital platforms are discussed, and their respective strengths in spatial resolution and single-molecule sensitivity are highlighted. Finally, future advancements are envisioned through interdisciplinary integration with artificial intelligence, microfluidics, and other cutting-edge technologies, which may facilitate transformative applications in precision medicine and related fields.

The commercialization of lithium-sulfur (Li-S) batteries faces persistent challenges, including the polysulfide shuttle effect, poor electrical conductivity of sulfur cathodes, and severe volumetric expansion during cycling. To address these limitations while aligning with carbon neutrality objectives, this study innovatively utilizes waste-activated sludge (a byproduct of wastewater treatment) as a sustainable precursor to synthesize hierarchical porous, heteroatom-doped biochar (designated SC) through a multi-step process involving chemical etching, K₂CO₃ activation, and controlled pyrolysis. Structural characterization demonstrates that the optimized SC material exhibits a three-dimensional interconnected hierarchical pore architecture, achieving a remarkable specific surface area of 1643.3 m²•g⁻¹ which is higher compared to unactivated sludge-derived carbon (USC). Crucially, HF etching prior to activation effectively removes inert SiO₂ components, while K₂CO₃ activation at 800 ℃ under N₂ atmosphere induces micropore formation and graphitization, as evidenced by X-ray diffraction (XRD). Chemical composition analysis reveals that SC possesses dual heteroatom doping, featuring abundant polar functional groups including C=O, C—O, graphitic-N, pyrrolic-N and pyridinic-N, which synergistically enhance polysulfide chemisorption. Ultraviolet-visible spectroscopy confirms SC's exceptional adsorption capacity for Li₂S₆, with complete elimination of characteristic absorption peak at 350 nm, outperforming USC and raw sludge-derived carbon (designated DS). When employed as a sulfur host, the SC-based cathode delivers a high initial discharge capacity of 1165.5 mAh•g⁻¹ at 0.1 C, maintaining 92.3% capacity retention after 50 cycles and achieving an ultralow capacity decay rate of 0.05% per cycle over 1000 cycles. Even under high sulfur loading (8 mg•cm⁻²), the cathode retains 55.0% capacity after 500 cycles at 0.5 C, demonstrating practical viability. Mechanistic studies attribute this performance to the synergistic effects of physical confinement (hierarchical pores), chemical adsorption (polar functional groups), and enhanced reaction kinetics (low charge-transfer resistance, R_ct=177.9 Ω; fast Li⁺ diffusion coefficient). Furthermore, sludge-derived SC reduces material costs lower compared to commercial carbon while aligning with carbon neutrality goals via waste-to-resource conversion. This work provides a green and cost-effective paradigm for designing high-energy-density Li-S batteries and valorizing biowaste in energy storage systems.

As a revolutionary single-molecule sequencing technology, nanopore DNA sequencing technology leverages the non-covalent interactions between nano-confined sensing interfaces and DNA molecules to parse the base information, then reading the DNA sequence at the single-molecule level. This physical method for direct reading of DNA offers unique advantages such as label-free, long reads, high-throughput, cost-effective, and real-time detection, demonstrating immense potential in genomics research and medicine science. This review summarizes the principles and development history of biological nanopore-based single-molecule DNA sequencing, focusing on key aspects including the engineering of biological nanopores for spatial resolution improvement, motor protein-based strategies of DNA translocation for time resolution control, and the construction of nanopore sequencing systems, then going deep into the underlying connection of these factors. Based on these, the current application and future development of nanopore-based single-molecule sequencing technology has been discussed.

Low-dimensional magnetic materials, which can simultaneously utilize the electrons’ spin and charge degrees of freedom for data storage, processing and transmission, exhibit significant potentials for applications in next-generation information technologies. However, the development of low-dimensional magnetic materials faces severe challenges such as the difficulties of experimental synthesis and characterization, usually low Curie temperatures, lack of effective modulation, and limited function integration. First-principles design of novel low-dimensional functional magnetic materials has thus emerged as a crucial approach to addressing these issues. In this context, organometallic systems have garnered widespread attentions due to their rich chemical tunability. Their diverse transition metal centers and extensive organic ligand libraries provide a vast design space for low-dimensional magnetic materials. The precisely controllable coordination environment can effectively modulate the charge and spin states of metal/ligand centers. Moreover, the coordination bonds between metals and ligands exhibit diverse and adjustable orbital coupling, offering an ideal platform for achieving high Curie temperatures and varied magnetic interactions. Additionally, the chemical modifiability and conformational flexibility of organic ligands facilitate the construction of magnetic phase-transition systems and multifunctional spintronic devices. This review aims to systematically summarize recent advances in the first-principles design of low-dimensional magnetic organometallic materials with targeted functions. Several key design strategies are highlighted, including methods for constructing stable magnets with long-range room-temperature ferrimagnetism, chemical modulation strategies for magnetic phase transitions, approaches to designing room-temperature multiferroic materials, principles for creating metal-organic materials with giant Rashba effects, design rules for bipolar magnetic molecules, inverse design of altermagnetic metal-organic frameworks (MOFs), and microscopic mechanisms of electric-field-controlled magnetism. Finally, the integration of machine learning methods to achieve low-dimensional metal-organic magnets with high magnetic anisotropy is discussed. By systematically outlining the unique advantages and existing challenges of organometallic systems in the design of low-dimensional magnetic materials, along with the latest experimental breakthroughs, this review is expected to provide theoretical guidance and technical pathways for future related researches.

Lithium-air batteries are considered promising candidates for the development of advanced energy storage systems due to their exceptionally high theoretical energy densities. Taking lithium-oxygen batteries as an example, their theoretical specific energy can reach up to 3500 Wh/kg. However, lithium-air batteries, including lithium-oxygen and lithium-carbon dioxide batteries, still face significant challenges on the cathode side, such as sluggish reaction kinetics, high overpotentials, and side reactions caused by electrolyte decomposition. During discharge, gaseous reactants such as O₂ or CO₂ are reduced at the cathode to form solid discharge products like peroxides, carbonates, or oxalates. These products typically possess poor electronic and ionic conductivity, which can passivate the electrode surface, leading to catalyst deactivation and capacity limitations. In the subsequent charging process, the poor “solid-solid” contact between the catalyst and these insulating discharge products makes them difficult to decompose efficiently, resulting in high overpotentials, low coulombic efficiency, and severe parasitic reactions. To address these issues, researchers have introduced redox mediator (RM) molecular catalysts to convert the “solid-solid” interface into a more efficient “solid-liquid-solid” interface. RMs transfer electrons between the electrode and the discharge products in solution phase, enabling their oxidation and fully decomposition, thereby improving the poor contact of “solid-solid” interface and significantly improving the electrochemical performance of lithium-air batteries. This review briefly introduces the current status and key challenges in lithium-air battery research and, using lithium-oxygen batteries as a representative system, systematically discusses the catalytic roles, mechanisms, and advantages and disadvantages of redox mediators during both discharge and charge processes. Furthermore, the design principles and technical barriers in developing ideal redox mediator catalysts are analyzed, and future perspectives for this research field are proposed.

Alumina (Al₂O₃) materials are widely utilized in aerospace, military, dental restoration, automobile manufacturing and electronic applications due to their high strength, hardness, and chemical stability. However, their inherent brittleness and low fracture toughness (typically below 4.5 MPa•m^1/2) limit their application in load-bearing components. This review systematically summarizes recent advances in strengthening and toughening strategies for Al₂O₃ and Al₂O₃-based composites, focusing on three key approaches: phase regulation, compositional optimization, and bioinspired micro-nano structural design. Phase regulation strategies, such as amorphous Al₂O₃ and crystal-amorphous dual phase structures, enhance toughness through shear band slip and uniform plastic deformation (e.g., amorphous Al₂O₃ layers achieve tensile strength of 4.8 GPa with 30% strain). Compositional optimization involves introducing secondary phases like oxides (e.g., ZrO₂, Y₂O₃) to refine grains and induce crack deflection (fracture toughness up to 9.38 MPa•m^1/2), carbon materials (e.g., graphene, SiC) for crack bridging and branching (40% toughness improvement), and metals (e.g., Cu, Ni) to enhance interfacial bonding and energy dissipation (energy density of 10 J•g^-1). Micro-nano structural designs inspired by natural nacre (“brick-mortar” architecture), 3D interlocking, and Bouligand structures achieve synergistic high strength and high toughness via multiscale crack deflection and bridging. Challenges remain in stabilizing amorphous phases, strengthening heterogeneous interfaces, and scaling up biomimetic pure ceramic architectures. Future directions emphasize pure ceramic composites with high-performance, interfacial engineering, and scalable fabrication of hierarchical structures to expand applications in extreme environments. This review provides critical insights and technical guidelines for developing next-generation high-performance Al₂O₃ and Al₂O₃-based composites.

Micro/nano-fabrication technology, as a critical bridge between materials and functional devices, holds significant applications in information technology and flexible electronics. Conventional complementary metal-oxide-semiconductor (CMOS) processes are constrained by harsh conditions such as etching and high-temperature treatments, thus facing challenges in processing emerging materials. Solution-based methods offer mild processing, yet navigating the trade-offs between macroscopic size uniformity, microscopic position precision, and ordered material assembly. Addressing these limitations, the liquid-bridge-confined assembly strategy enabled by superwetting interface engineering has emerged as a novel paradigm for cross-scale manufacturing through precise manipulation of microfluidic directional transport and ordered assembly of material units. This review systematically elucidates the dynamic mechanisms underlying liquid-bridge-confined assembly, revealing fundamental principles governing the regulation of three-phase contact lines and liquid bridge architectures through superwetting surface design. The technology demonstrates exceptional capability in high-precision patterning and long-range ordered assembly of solution-processable materials spanning organic molecules, polymers, quantum dots, and microparticles via confinement effects. Furthermore, the review critically examines how long-range order of material architectures enhance device performance and functional diversification in optoelectronics and microelectronics, exemplified by recent advancements in: (1) microlaser arrays with controlled mode coupling, (2) laser-waveguide coupling devices, (3) quantum dot light-emitting diodes (QLEDs), (4) polarization-sensitive photodetectors, and (5) flexible wearable systems. Finally, the review concludes by highlighting the universal applicability of liquid-bridge-confined assembly across multi-material systems and complex substrates, while outlining future directions in photonic integration, wearable biotechnology, and quantum information processing through programmable interfacial engineering.

Uranium (U) is the dominant fuel for nuclear reactors, and uranium extraction from seawater is a promising method to ensure the sustainable development of nuclear energy. However, the development of adsorbents for practical applications remains a challenge due to the extremely low concentration (≈3.3 μg•L⁻¹) and its propensity to form carbonate complexes of uranium, as well as the presence of high concentrations of competing ions. The adsorption performance of adsorbents is affected by the pore size and the distribution of adsorption active sites. Excessively narrow pores will restrict the access of target ions and thus reduce the adsorption rate. Increasing pore sizes is effective to promote the adsorption kinetics but may undermine coordination stability. How to balance the relationship between adsorption capacity and adsorption kinetics is a very important issue in the process of pore size regulation. In this study, titanium-based metal-organic frameworks (Ti-MOFs) were synthesized by solvothermal method and pore size regulation strategy was utilized to improve the extraction efficiency of uranium. The materials were systematically characterized by powder X-ray diffraction (PXRD), Brunauer- Emmett-Teller (BET), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA), demonstrating successive synthesis of Ti-MOFs. Compared to MOF-902 with larger pores, MOF-901 adsorbents with smaller pores exhibit a higher extraction efficiency for uranium, with an adsorption capacity of up to 468.5 mg•g⁻¹. The adsorption mechanism was investigated by X-ray photoelectron spectroscopy (XPS), pore size distribution and crystal structure analysis, and it was proved that MOF-901 is mainly coordinated with U through the N sites in the pore architecture and steric hindrance effect as well as pore size effect are closely related to the uranium adsorption capacity of Ti-MOFs. Adsorption experiments in simulated seawater (initial concentration of 10 mg•L⁻¹) were also carried out, and the adsorption efficiency of uranium by MOF-901 was more than 99%, demonstrating the potential application of Ti-MOFs in the field of uranium extraction from seawater.

Sodium metal batteries (SMBs) have emerged as promising next-generation energy storage systems due to sodium’s high theoretical specific capacity (1076 mA•h•g^－1) and natural abundance in the Earth’s crust (2.3%). However, dendrite formation during cycling leads to safety risks and rapid capacity degradation. This review provides a comprehensive analysis of three-dimensional (3D) carbon-based current collectors (CCs) as transformative platforms to regulate Na⁺ deposition. 3D carbon architectures, such as carbon nanotubes, graphene aerogels, and carbon cloth, offer high surface areas (500~1500 m²•g^－1), robust mechanical frameworks, and optimized ion transport pathways, effectively reducing local current density and nucleation overpotential by 40%~60%. Firstly, the fabrication technologies are critically discussed. The template methods enable precise pore control (1~50 mm) but risk structural collapse. Sacrificial templates (e.g., MOFs) address this limitation, yielding composites with high conductivity and specific capacity (>600 mA•h•g^－1). The use of 3D-printed nitrogen-doped graphene aerogels (3DP-NGA) facilitates dendrite-free sodium deposition, where pyrrolic-N defects act as nucleation sites to guide uniform Na plating, even in complex architectures. Electrospinning produces binder-free mesoporous carbon nanofibers (MCNFs), while chemical vapor deposition (CVD) synthesizes graphitic domains with tunable porosity. Atomic doping of 3D carbon materials can increase their sodium affinity, thereby promoting more uniform sodium deposition. Functionalization strategies such as alloying and incorporating organic or inorganic composites can further enhance sodiophilicity and help form a stable solid electrolyte interphase (SEI) during cycling. In addition, rational pore design can effectively regulate sodium plating and stripping behavior, thereby suppressing dendrite growth. Looking ahead, we envision several promising opportunities and pressing challenges: advancing in situ characterization techniques to unravel the fundamental structure-performance correlations; harnessing machine learning-driven inverse design to accelerate materials discovery; developing scalable roll-to-roll manufacturing strategies for gradient-doped CCs with projected costs below $5/m²; and integrating these architectures with solid-state electrolytes to unlock energy densities surpassing 500 W•h•kg^－1. Overall, this review establishes 3D carbon-based CCs as pivotal enablers for practical SMBs, bridging fundamental research and industrial implementation through multidisciplinary innovation.

Molecular diffusion in chemical reactions has been observed to deviate from the Stokes-Einstein relationship, however underlying mechanism remains elusive. The diffusion kinetics of enzymatic and small-molecule chemical reactions have shown that some reactants or catalysts exhibit enhanced translational diffusion coefficients exceeding their intrinsic values by over 20%, with minimal temperature fluctuations. While molecular motion inherently couples translational and rotational components, previous studies have primarily focused on translational diffusion, leaving rotational diffusion largely unexplored. In this study, the rotational diffusion coefficients of species involved in the Cu(I)-catalyzed 1,3-dipolar cycloaddition between 3-butynoic acid and azidoacetic acid were investigated through two independent measurements. Specifically, the changes in the translational diffusion coefficients of the substrate and product during the reaction of 3-butynoic acid and azidoacetic acid were determined by nuclear magnetic resonance (NMR) diffusion-ordered spectroscopy, and a significant increase in the substrate's diffusion coefficient was observed at the early stage of the reaction, which confirms a nonclassical diffusion phenomenon in this system. Subsequently, rotational diffusion coefficients of each species during the reaction were measured using a T₁ inversion recovery experiment, the values for both the substrate and the product showed a significant increase as the reaction progressed while the values for sodium ascorbate remained unchanged. Rotational diffusion was further measured by an independent fluorescence anisotropy/polarization experiment. The changes in fluorescence anisotropy were consistent with the NMR experiments, confirming the presence of nonclassical rotational diffusion in the reaction. The changes in rotational and translational diffusion coefficients of 3-butynoic acid and azidoacetic acid were found both strongly correlated with reaction progress and in synchronization. In summary, interpretating from two independent measurements based on NMR and fluorescence anisotropy, we propose that molecular alignment and the conversion of rotational to translational energy contribute to deviations from the Stokes-Einstein relation during reaction.

Organic narrowband photodetectors (NBPDs) have garnered substantial research attention within optoelectronic technology due to their superior spectral resolution and significant potential for applications in biomedical sensing, machine vision, and hyperspectral imaging. Conventional approaches to achieve spectral selectivity, which rely heavily on discrete optical filters or intricate device engineering strategies (e.g., charge collection narrowing, charge injection narrowing and exciton dissociation narrowing), suffer from inherent limitations including compromised device integration density, increased fabrication complexity, and elevated costs. The absorption spectra of organic optoelectronic materials can be accurately regulated through rational design of molecular structures, which exhibits great superiority in constructing narrowband photodetectors. This perspective reviews organic NBPDs based on narrowband absorption materials, analyzing strategies from both molecular design and aggregation-state modulation perspectives. Molecular design covered include metal phthalocyanines, cyanine dyes, merocyanine dyes, squaraine dyes, donor-acceptor (D-A) systems, multi-resonance (MR) systems, non-charge- transfer (non-CT) systems, and boron-dipyrromethene (BODIPY) derivatives. While conventional dyes and D-A molecules typically achieve detection full width at half-maximum (FWHM) no less than 50 nm, emerging MR and non-CT systems demonstrate exceptional potential for sub-50 nm FWHM. This enhanced narrowness stems from their unique photophysical properties—MR systems feature suppressed vibrational coupling due to non-bonding molecular orbitals, while non-CT systems utilize localized excitons. Aggregation-state control, particularly J-aggregation, is highlighted as a powerful strategy to counteract spectral broadening in solid-state films. J-aggregates, formed by a specific slipped-stack molecular arrangements, exhibit red-shifted sharp absorption due to suppressed vibronic couplings. Despite considerable progress, significant challenges still exist in further compressing FWHM below 20 nm, achieving reliable control over aggregation processes during large-area fabrication, standardizing the reporting of crucial figures of merit like spectral rejection ratio (SRR) to enable fair cross-lab comparisons, and developing materials specifically optimized for key application wavelengths beyond the visible range. Addressing these hurdles demands a synergistic approach combining advanced molecular engineering, precise aggregation control, and innovations in device fabrications to realize the full potential of high-performance organic NBPDs for next-generation optoelectronic applications.

Neurotransmitters are essential mediators of neuronal communication, governing neural circuit plasticity and maintaining cerebral functional homeostasis. They can be classified into major categories including monoamines, amino acids, acetylcholine, neuropeptides, purines, gaseous neurotransmitters, etc. Deciphering the dynamic fluctuations in neurotransmitter concentrations and distributions is paramount for elucidating fundamental neurophysiological processes and unraveling the mechanisms underpinning neuropathological conditions, such as Alzheimer's disease, Parkinson's disease, depression, etc. Fluorescence imaging technique employs specific probes that transduce the biochemical event of neurotransmitter recognition into a quantifiable optical signal, enabling non-invasive, highly specific visualization with high spatiotemporal resolution in live systems, representing an exceptionally promising class of tools for neurotransmitter detection. Owing to the compact size, excellent structural stability, high biocompatibility, tunable photophysical properties, and designable recognition mechanisms, organic small-molecule fluorescent probes act as ideal candidates for sensitive and selective neurochemical imaging. This review examines the advancements in the development and application of organic fluorescent probes for neurotransmitter detection, focusing on molecular designs, recognition principles (covalent or non-covalent interactions), signal transduction mechanisms (e.g., photoinduced electron transfer, intramolecular charge transfer, fluorescence resonance energy transfer), analytical performance, and their imaging capabilities in live cells, tissues, and in vivo models. A dedicated section provides a critical analysis of the prevailing limitations hindering broader application of current organic small-molecule fluorescent probes, such as challenges with reversibility, slow response times, photobleaching, limited multiplexing capability, insufficient blood-brain barrier penetration, and depth limitations in in vivo imaging. Building upon this assessment, we offer forward-looking perspectives on the future trajectory of fluorescent probe development. Key focus areas include engineering probes with enhanced binding kinetics and reversibility for real-time monitoring, superior photostability for longitudinal studies, capabilities for multiplexed analysis, ideal excitation/emission properties for deeper tissue penetration, and improved pharmacokinetic properties for efficient BBB crossing. This review aims to provide strategic design insights and a developmental roadmap for the next generation of high-performance neurochemical probes, thereby advancing fundamental neuroscience research and clinical diagnostic technologies.

The ever-growing energy demand poses significant challenges for developing clean and sustainable energy solutions, making the establishment of low-cost, environmentally benign, and efficient energy storage systems a critical focus for societal development. Lithium ion batteries (LIBs), as a mature electrochemical energy storage technology, currently dominate the market and have achieved large-scale implementation in electric vehicles. However, the escalating application costs of LIBs, driven by lithium resource scarcity and geopolitical constraints, have intensified the search for alternatives. Sodium ion batteries (SIBs) emerge as a promising next-generation low-cost storage solution, benefiting from electrochemical energy storage mechanisms analogous to LIBs while leveraging sodium's natural abundance. As a pivotal component of SIBs, cathode materials not only dictate battery performance but also critically determine system-level costs. Current SIB cathode materials primarily fall into three categories: layered oxides, Prussian blue analogs, and polyanionic compounds. Among these, Na₂Fe₂(SO₄)₃ (NFS) demonstrates exceptional structural stability and rate capability. The strong inductive effect of SO2- 4 groups endows NFS with a high working voltage of 3.8 V, translating to superior energy density. Furthermore, NFS exhibits advantages in raw material accessibility and environmental compatibility, aligning with sustainable development principles and positioning it as an ideal candidate for commercial SIB cathodes. Nevertheless, practical deployment of NFS in large-scale energy storage systems faces fundamental challenges: (1) intrinsic low electronic conductivity limits charge transfer kinetics, (2) interfacial instability during prolonged cycling causes capacity degradation, and (3) difficulties in synthesizing phase-pure structures compromise electrochemical reproducibility. This review begins with an in-depth analysis of the crystal structure and sodium ion insertion/extraction mechanism of NFS materials, systematically summarizing their synthesis methodologies and existing challenges. Modification strategies from perspectives including non-stoichiometric design, elemental doping, and carbon coating engineering are further overviewed. The review then extends to industrial-scale production progress, addressing key technical bottlenecks in manufacturing. By integrating fundamental mechanisms with practical applications, this work aims to provide effective guidance for enhancing the electrochemical performance of NFS materials and accelerating their commercialization, ultimately contributing to the development of cost-effective and high-performance sodium-ion battery systems.

Radioisotopes of lead have been extensively utilized in interdisciplinary research across nuclear science, healthcare applications, geology, and environmental science since the 20th century, serving as the interdisciplinary bridge connecting different disciplines. Due to the rapid development of nuclear medicine in recent years, the lead-203 and lead-212 radioisotopes have shown significant potential for cancer theranostics, with the ability for accurate diagnosis and effective treatment of tumor. Lead-202 and lead-205 are key components of uranium-lead spikes, which are widely applied in geochronological research on the isotope dilution mass spectrometry (ID-MS) for uranium-lead (U-Pb) dating. As a member from the decay chain of uranium-238, the behavior of lead-210 has been considered as a key mark in sediment dating, atmospheric aerosol transport phenomenon investigation and the monitoring of potential leakage of nuclear fuel from nuclear facilities. However, the production of the above-mentioned lead radioisotopes remains highly challenging, and the current supply is not able to meet the growing demands of these lead radioisotopes across various research fields. In this review, the application of a few selected lead radioisotopes in interdisciplinary research is summarized, with a focus on the production and purification methods for the lead radioisotopes. Finally, insights into prospects for the production and utilization of key radioactive lead isotopes in the future are given.

The mechanical properties of the extracellular matrix (ECM), including stiffness and stress relaxation, play an instructive role in regulating cellular behaviors. Given the inherent heterogeneity of tissue viscoelasticity in vivo, the precise influence of viscoelastic variations on cellular behaviors remains incompletely understood. To study these mechanobiological responses in vitro, gradient hydrogels have been developed to mimic the mechanical heterogeneity of native ECM. However, current fabrication strategies, including photomask polymerization and diffusion-based methods, face several limitations, such as complex operation, narrow material applicability, and compromised biocompatibility due to harsh reaction conditions. To address this challenge, we developed a programmable syringe pump system (PSPS) comprising three syringe units to fabricate a gradient viscoelastic hydrogel (GoHG) at a 600 μm scale. The hydrogel was synthesized through dynamic imine crosslinking between oxidized hyaluronic acid (oxi-HA) and gelatin, with precise spatial control over viscoelastic properties achieved by independently modulating the flow rates of individual injection units. This strategy enabled precise control over hydrogel composition, resulting in continuous stiffness gradients (19~47 kPa) and stress relaxation gradients (6~62 s) while maintaining excellent cytocompatibility (>95%). The results on the effect of viscoelastic gradient on cell spreading behavior indicate that different cell types exhibited distinct responses to the viscoelastic gradient. Fibroblasts (NIH-3T3) displayed enhanced spreading behavior in regions with higher stiffness (28.5 kPa) and slower stress relaxation (34.7 s), whereas myoblasts (C2C12) showed larger spreading area in areas with lower stiffness (23.6 kPa) and faster stress relaxation (30.0 s), highlighting cellular specificity to mechanical cues. These findings underscore the importance of viscoelasticity as a critical regulator of cell behavior. In conclusion, the PSPS-based fabrication method offers significant advantages, including simplicity, scalability, and broad material compatibility, making it a versatile platform for mechanobiology research. Furthermore, this approach advancing our understanding of cell-ECM mechanical interactions and shows great potential for tissue engineering applications, where mimicking native ECM mechanics is essential for guiding cell function and tissue regeneration.

Transparent conductive fiber is an indispensable part of textile displays. The predominant strategy for fabricating transparent conductive fiber involves doping ionic liquid into polymer matrix. However, low conductivity of ionic liquid renders the fiber inadequate for practical application. Herein, we developed a flexible transparent conductive fiber exhibiting high conductivity, and high transparency by coating Ag nanowires (AgNWs) onto thermoplastic polyurethane (TPU) fibers treated with air plasma. The specific synthesis processes are as follows: TPU fiber was cleaned in an ultrasonic bath using ethanol and deionized water respectively for 5 min each. The cleaned TPU fiber was treated by air plasma at 150 W for 3 min. The obtained fiber was then dip-coated in 2 mg•mL^-1 AgNWs ethanol dispersion for 1 min and dried in air for 5 min. After repeating 3 times of dip-coating process, the TPU@AgNWs transparent conductive fiber was prepared. The hydrophobicity of TPU impedes uniform adhesion and morphological stability of directly applied hydrophilic AgNWs conductive coatings on TPU fibers. Following plasma treatment, abundant hydrophilic groups are uniformly introduced onto TPU fiber surface. Water contact angle diminishes with the extended time of plasma treatment, verifies the hydrophilicity improvement of TPU fiber. X-ray photoelectron spectroscopy (XPS) reveals increasing C—O/C—N and N—O bond contributions derived of hydrophilic groups. These groups form hydrogen bonds with the polyvinyl pyrrolidone (PVP) coating on the AgNWs, resulting in a strong and uniform adhesion of the AgNWs layer to the TPU fiber substrate. The transparent conductive fiber achieves a conductivity of 10 S•cm⁻¹, which is 1000 times of the TPU@ionic liquid fiber, combined with a transparency exceeding 75%. After 14 d of ambient storage and 100,000 bending cycles, it retains over 90% of its initial conductivity. The as-prepared TPU@AgNWs transparent conductive fibers were weaved into a textile with luminescent fiber electrodes (a copper fiber successively coated BaTiO₃ dielectric layer, ZnS phosphor layer and polyurethane encapsulation layer) by an industrial rapier loom to prepare a textile display. The TPU@AgNWs transparent conductive fibers enable display luminance reaching 208 cd•m^-2, along with excellent washability and abrasion resistance.

Covalent organic frameworks (COFs), with their structural tunability, high specific surface area, and excellent chemical stability, have attracted increasing attention in the field of proton conductors in recent years. This review systematically summarizes the research progress of COF-based proton conductors, covering proton transport mechanisms, material design strategies, experimental characterization, theoretical simulation methods, and application prospects. Criteria for distinguishing between the Grotthuss mechanism, which involves proton relaying through a hydrogen-bonding network, and the Vehicle mechanism, which entails diffusion of protonated species, have been clarified based on extensive experimental measurements of activation energies and theoretical simulations of proton transport pathways. In general, an activation energy below approximately 0.4 eV suggests dominance of the Grotthuss mechanism, whereas higher values typically indicate the predominance of the Vehicle mechanism. Proton-conducting materials are commonly categorized into intrinsic and extrinsic systems based on the source of protons. Intrinsic systems construct stable conduction pathways by covalent bonding to anchor sulfonic acid groups, phosphate groups, or nitrogen heterocycles. Extrinsic systems are optimized for proton transport by loading H₃PO₄, ionic liquids, or polymers using confinement effects. In terms of experimental characterization techniques, electrochemical impedance spectroscopy (EIS) was employed to measure macroscopic conductivity and activation energy. Simultaneously, solid-state nuclear magnetic resonance (ssNMR) was utilized to the local chemical environment of protons, X-ray photoelectron spectroscopy (XPS) for analyzing the charge distribution of functional groups, and infrared spectroscopy for monitoring chemical bond vibrations and transformations. Furthermore, the potential applications of quasi-elastic neutron scattering (QENS) and isotope tracing techniques in other materials were also briefly discussed. Theoretical simulation methods encompass density functional theory (DFT), for calculating electrostatic potential and, combined with transition state search methods, proton migration energy barriers, classical molecular dynamics (MD), for calculating radial distribution function (RDF) and coordination number, and ab initio molecular dynamics (AIMD), for dynamic tracking of proton migration pathways. These methods have collectively revealed the microscopic regulatory mechanism of proton transport through pore geometry, functional group arrangement, and synergistic effects of hydrogen bonding. Finally, this review analyzes the application prospects of COF proton conductors in electrochemical energy conversion devices. We propose that integrated efforts in the design, experimental characterization, and theoretical simulation of COFs are essential for achieving performance optimization and advancing towards practical application, thereby enhancing proton conduction efficiency and material stability. Future research should integrate high-resolution characterization and multi-scale simulation to gain a comprehensive understanding of the proton transport mechanisms in COF materials, thus accelerating the application of COF-based conductors in promising hydrogen energy technologies.

Organic electro-synthesis has emerged as a transformative platform in modern synthetic chemistry, witnessing remarkable progress through its strategic replacement of stoichiometric chemical redox reagents with traceless electron. This paradigm shift not only enhances atom economy but also reduces chemical waste generation, aligning with green chemistry 12 principles. During the past years, considerable progress has been made in this area. However, the majority of these reactions require the use of stoichiometric supporting electrolytes to ensure adequate ionic conductivity, thus increasing the environmental and economic cost. As a result, the development of intrinsic supporting electrolyte-free electrochemical systems represents an essential frontier in sustainable synthesis, promising simplified reactor configurations and enhanced process sustainability while maintaining the inherent advantages of electro-synthetic activation. Quinoxalin-2(1H)-ones, especially 3-functionalized quinoxalin-2(1H)-ones, are important scaffolds featured in diverse natural products and pharmaceuticals, and possess a broad range of biological and pharmacological activities. The direct C3-H functionalization of quinoxalin-2(1H)-ones has been considered as an atom- and step-economic strategy for the construction of various 3-functionalized quinoxalin-2(1H)-ones. Notably, about 30% of top-selling 200 pharmaceuticals (2023) contain a benzyl group. Among various 3-functionalized quinoxalin-2(1H)-one derivatives, 3-benzylquinoxalin-2(1H)-ones as a valuable pharmacophore are found in numerous biologically active molecules. Consequently, the development of more green and efficient methods for synthesizing 3-benzylquinoxalin-2(1H)-ones is highly desirable in organic and pharmaceutical chemistry. Benzyl chlorides are low cost and abundant feedstock materials, which have been widely used as the benzylation reagents in organic synthesis. In the present work, we report the development of supporting electrolyte-free electrochemical benzylation of quinoxalin-2(1H)-ones with benzylic chlorides. With graphite plate as the anode, platinum plate as the cathode, dimethylsulfoxide as the solvent, a series of 3-benzylquinoxalin-2(1H)-ones were efficiently constructed via dechlorinative coupling reaction. The supporting electrolyte-, catalyst-free and mild conditions, readily available reactants, wide substrate scope and large-scale synthesis make the present strategy highly attractive in organic and pharmaceutical chemistry.

Polyethylene wax has the physical properties of ethylene oligomer, and can be used as lubricant, stabilizer and adhesive. It is widely used in plastics, rubber, ink, cosmetics and other fields. Its preparation technology has been upgraded from the traditional thermal cracking process to catalytic ethylene polymerization technology. In this work, we synthesized three iminopyridyl nickel catalysts Ni1~Ni3 with different steric effects and bulky 2,4,6-tris(4-fluorophenyl)methyl substituents, and investigated their catalytic performance in ethylene chain-walking polymerization processes. Results demonstrated that catalyst structure and polymerization conditions directly influence ethylene catalytic activity, as well as the molecular weight and branching degree of the resulting polyethylene wax. All catalysts successfully produced branched polyethylene waxes with methyl groups and long side chains, exhibiting narrow dispersion. By adjusting polymerization temperature (0~75 ℃), the branching structure of polyethylene wax could be effectively controlled (15~61/1000C). A solid powder of polyethylene was obtained at lower temperatures, primarily composed of methyl branches. These catalysts exhibited nearly identical superior performance to toluene in industrial solvent n-heptane. The Ph-substituted Ni2 showed high catalytic activity of 4.55×10⁶ g•mol^－1•h^－1 in n-heptane versus 4.72×10⁶ g•mol^－1•h^－1 in toluene. This technology enables direct synthesis of branched polyethylene wax materials through chain-walk polymerization, featuring simple preparation, cost-effectiveness, high catalytic efficiency, and excellent solvent tolerance. It paves new pathways for high-value production of polyethylene waxes in industrial applications.

Zero-valent main group elements give rise to a diverse array of allotropes through various bonding modes, such as covalent network bonding, molecular aggregation and polymeric chain formation. This structural diversity not only reflects the intrinsic bonding flexibility of these elements but also showcases their significant application potential in synthetic chemistry and the development of advanced new materials. In recent years, with the rapid advancement of main group element chemistry, ligand-stabilized low-valent main group element compounds have garnered increasing attention. Compounds containing zero-valent main group elements feature electron-rich main group element centers and exhibit extremely high reactivity, making their stable existence difficult to achieve for a long time. With the design and development of novel ligands for low-valent main group elements, a series of groundbreaking zero-valent main group element compounds have been successfully synthesized and characterized.​ Among these, ligand-stabilized mono- and dinuclear zero-valent main group element compounds exhibit unique electronic structures, and their isolation and characterization enhance our understanding of the bonding mechanisms associated with zero-valent main group elements. Since the differences in the electronic properties of ligands significantly affect the bonding modes between zero-valent element atoms and ligands, such compounds usually exhibit unique electronic structural characteristics and a rich variety of chemical reactivities. Furthermore, their excellent solub ility in common organic solvents greatly broadens their applications in homogeneous synthetic chemistry. Additionally, due to the unusual oxidation states of the central elements, zero-valent main group element compounds show promise in small molecule activation. This review mainly summarizes the synthesis of zero-valent compounds of elements from Group 13 to 15 in the p-block of the periodic table as well as a few alkaline earth metal elements in the s-block. The article elaborates on their isolation, electronic structures and bonding modes, and unique chemical reaction properties while addressing the challenges they face in this field and outlining future development directions.

Nitrogen-containing heterocycles are the most common structural units in numerous natural products, drugs, and bioactive compounds. Among them, functionalized tetrahydropyridine derivatives are widely present in many alkaloids, biologically active molecules and drug molecules. Consequently, the synthesis of this class of nitrogen heterocyclic compounds has attracted widespread attention from chemists. Despite many known powerful methods, some of the existing protocols still require use of expensive transition metal catalysts or harsh reaction conditions, thus limiting their extensive application. Herein, we report an efficient and practical method for synthesis of functionalized 1,2,3,6-tetrahydropyridine derivatives by visible-light-induced nitrogen radical-mediated addition/cyclization of vinylcyclopropanes. This process involves controlled generation of sulfonamidyl radicals from N-aminopyridinium salts to trigger the addition/cyclization reaction with vinylcyclopropanes. This work not only enriches the reaction scope of photogenerated nitrogen radicals, but also provides a new approach for the construction of 1,2,3,6-tetrahydropyridines. Notably, the N-aminopyridine salts in this reaction act as a bifunctional reagent, both as a nitrogen radical precursors and a nitrogen nucleophilic reagents. Vinylcyclopropanes serve as versatile four-atom coupling partners, undergoing radical addition followed by ring-opening and cyclization. This work significantly expands synthetic approaches for heterocyclic construction by demonstrating a novel reaction mechanism for visible-light-catalyzed nitrogen radical generation, providing a direct and modular synthetic pathway for tetrahydropyridine core structures. After extensive condition screening, the optimal conditions for this reaction were determined as follows: 10-phenylphenothiazine (Ph-PTZ) as the photocatalyst and 1,2-dichloroethane (DCE) as the solvent under irradiation of 390 nm purple LEDs. Subsequently, the substrate scope of N-aminopyridine salts and vinylcyclopropanes was examined, leading to the synthesis of 42 examples of 1,2,3,6-tetrahydropyridine analogs in up to 77% isolated yield. In addition, this method can be scaled up to the gram scale while the product undergoes various transformations of functional groups. Finally, a possible reaction mechanism was proposed for the reaction based on free radical trapping experiments and fluorescence quenching experiments.