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Lithium metal anodes suffer from dendrite growth, low coulombic efficiency, and safety concerns, limiting their practical application in rechargeable batteries. Herein, polypropylene (PP) separators are functionalized with ultrathin 2D anionic (H₃Sb₃P₂O₁₄) HSPO nanosheets to construct a negatively charged interfacial layer. The HSPO layer improves electrolyte affinity, increases the Li⁺ transference number from 0.5 to 0.8, and guides a more homogeneous Li⁺ flux toward the lithium metal surface. Density functional theory calculations indicate stronger interactions between HSPO and Li/electrolyte species than those on pristine PP, while finite-element simulations and in situ optical microscopy reveal a more uniform electric-field distribution and regulated lithium deposition process. As a result, Li||Cu cells show improved plating/stripping stability over 250 cycles, and the Li||Li symmetric cell achieves a sevenfold increase in lifespan. Notably, the interfacial regulation strategy enables exceptional full-cell durability, delivering 2000 cycles for Li||LiFePO₄ at 1C and 12,000 cycles for Li||I₂ at 5C. This work highlights charged two-dimensional nanosheets as interfacial modifiers for separator-mediated regulation of ion transport and lithium deposition.

Aqueous zinc-ion batteries face severe challenges in practical cycling, mainly including irregular zinc dendrite growth and unstable interfacial reactions, which greatly degrade the cycling performance. Herein, via a facile immersion method relying on a one-step in-situ spontaneous displacement reaction, an organic-inorganic composite layer composed of organic components and copper nanoparticles are fabricated on the surface of the zinc metal anode. The upper layer is enriched with carboxyl groups and Cu²⁺, constructing the upper layer by coordination interactions. Acting as migration sites and transport pathways for Zn²⁺, the as-formed SEI layer induces the uniform and ordered deposition of zinc. The bottom layer is composed of zincophilic copper clusters, which can form a compact physical shielding layer on the zinc anode surface and effectively inhibit interfacial corrosion. Benefiting from the synergistic effect, the symmetric cell achieves an ultra-long cycle life of over 4000 h at 3 mA cm^-2, and still maintains a cycle life exceeding 2000 h even at a high current density of 10 mA cm^-2. Meanwhile, the Cu-BTC@Zn//MVO full battery exhibits a 57% increase in capacity retention compared with bare Zn anode after 700 cycles. Meanwhile, this work reveals the synergistic regulation mechanism of the organic-inorganic composite layer toward Zn deposition, and provides a facile and practical strategy to construct stable artificial SEI layers for high performance zinc-metal anodes.

The widespread use of glyphosate in agriculture has raised concerns about environmental contamination and associated health risks, creating an urgent need for rapid, sensitive, and field-deployable analytical tools. In this work, Zr/Eu-metal-organic framework (Zr/Eu-MOFs) as an integrated bimetallic ratiometric fluorescent hydrogel sensor for fast and highly sensitive visual detection of glyphosate has been developed. By doping Eu³⁺ into a robust Zr-based MOF framework, Zr/Eu-MOFs exhibit dual-emission bands at 445 and 618 nm, enabling an intrinsic self-referenced signal without multicomponent assembly. Upon glyphosate addition, the sensor responds within 10 s. Zr/Eu-MOFs display a reliable ratiometric response over 0.05 - 10.0 mg/L with a low detection limit of 0.03 mg/L (0.2 μmol/L), which is far below the permissible maximum residue limit (MRL) for drinking water by the US EPA and China (4.1 μmol/L). Mechanistic evidence indicates that glyphosate forms P-O-Zr coordination linkages and interfacial interactions which modulate the ligand-to-metal charge transfer (LMCT) process, resulting in an enhanced ratiometric fluorescence response at 445 nm, while the Eu³⁺ emission at 618 nm remains essentially unchanged. Moreover, an agarose hydrogel format coupled with smartphone image analysis enables rapid visual detection. A spraying-enabled fluorescence imaging strategy further allows rapid screening of glyphosate contamination on leaves, apple surfaces, and soil-water matrices under UV illumination. Overall, this work provides a facile, integrated, and visually readable ratiometric platform for on-site glyphosate monitoring.

Accurate detection of microRNAs is of great significance for the clinical diagnosis and therapeutic guidance of cancer. Herein, we have established an isothermal self-catalytic DNA circuit that can combine an autocatalytic hairpin assembly (ACHA) converter with autocatalytic hybridization chain reaction (AHCR) amplification for the sensitive detection of miRNA-21. HCR is initiated by the recognition of the target analyte, generating new trigger strands that subsequently activate the CHA amplifier. One terminus of the CHA amplifier is engineered to expose the identical HCR initiator sequence, thereby enabling sustained HCR propagation. The DNAzyme moiety at the opposite terminus functions as a fluorescent signal reporter, efficiently cleaving the fluorogenic reporter probe. Therefore, the self-catalytic feedback loop between the HCR and CHA systems allows trace targets to produce fluorescence signals with exponential amplification. This circuit conducted a sensitive, reliable and universal analysis of miRNA-21, with a detection limit of 33.4 fM. Self-feedback cascade circuits provide a promising tool for molecular sensing in complex biological environments, this cascaded circuit can be used for the analysis of miRNA-21 in human serum samples. It has broad application prospects in low-abundance biomolecular sensing and early diagnosis of diseases.

Copper ions (Cu²⁺) are essential micronutrients but become hazardous when accumulated in excess, necessitating reliable, sensitive, and field-deployable detection methods. Herein, we report a fluorescent Mn-based MOF nanozyme (Mn-TCPP) that exhibits intrinsic oxidase-like activity, capable of catalyzing the oxidation of non-fluorescent o-phenylenediamine (OPD) to fluorescent 2,3-diaminophenazine (DAP) with an emission peak at 560 nm, while the Mn-TCPP itself displays characteristic fluorescence at 655 nm. Upon exposure to Cu²⁺, the stronger affinity of Cu²⁺ toward the porphyrinic TCPP ligand displaces Mn²⁺ from the framework, forming Cu-TCPP. This metal-exchange process simultaneously quenches the 655 nm fluorescence of the MOF and attenuates its oxidase-mimicking activity, whereas free Cu²⁺ in solution independently catalyzes OPD oxidation, further enhancing the 560 nm emission. Leveraging this dual-response mechanism, we develop a ratiometric fluorescence sensing strategy for Cu²⁺ detection based on the intensity ratio F₅₆₀/F₆₅₅. The calibration curve follows a linear equation: F₅₆₀/F₆₅₅ = 0.201x-0.001 (0.2-10 μM, R² = 0.985) and y = 0.002x+2.061 (10-100 μM, R² = 0.994) with the limit of detection (LOD) of 81 nM (S/N = 3). The sensor exhibits excellent selectivity over competing metal ions, and the method reliability is validated by standard addition recovery experiments in real water and rice samples. Furthermore, the Mn-TCPP nanozyme is embedded into an agarose hydrogel matrix, enabling visual, instrument-free monitoring of Cu²⁺ contamination: increasing Cu²⁺ concentrations induce a discernible fluorescence color transition from orange to yellow under 365 nm illumination. This work presents a tunable MOF platform that exploits competitive targets synchronous modulation of fluorescence and enzyme-mimicking activity, providing a robust, selective, and field-deployable ratiometric sensor for Cu²⁺.

Solar-driven photocatalytic oxygen reduction offers a sustainable route for hydrogen peroxide (H₂O₂) production. However, this process is often limited by the high energy barrier for hydrogen extraction from water, low oxygen solubility and diffusion, and poor selectivity for the two-electron oxygen reduction reaction (ORR), especially under alkaline conditions. Herein, we reported a synergistic photothermal-photocatalytic bilayer aerogel constructed with konjac glucomannan to integrate a photothermal lower layer of reduced graphene oxide (rGO) and a catalytic upper layer of keto-form anthraquinone covalent organic framework (Kf-AQ-COF). Owing to its hydrophobic mesoporous structure, the bilayer aerogel forms a robust gas-liquid-solid triphase interface on a porous substrate. Under alkaline conditions, the hydroxide clusters adsorbed onto ketone moieties can drive the anthraquinone-anthrahydroquinone cycle of Kf-AQ-COF for enabling electron transfer and H₂O₂ production. Meanwhile, the underlying rGO layer functions primarily as a localized photothermal converter and lightweight structural matrix, raising the interfacial temperature to accelerate reaction kinetics and driving rapid vapor escape without altering the intrinsic band structure of the top photocatalyst. As a result, this photothermal-synergistic triphase interface achieves an H₂O₂ production rate of 15.0 mmol m^-2∙h^-1 under air without sacrificial agents within 60 min, which is 1.43 times that of the conventional solid-liquid diphase system. This work demonstrates a new photocatalytic strategy integrating molecular reaction regulation with interfacial engineering.

Antibiotic-resistant bacterial infections pose a global health crisis, driving the need for innovative diagnostic approaches. Conventional methods for detecting resistant strains and antibiotic susceptibility testing (AST) are often limited by long assay times, low sensitivity, and operational complexity. Herein, a novel gelatinase-responsive cascade microfluidic chemiluminescence (CL) biosensor was developed for ultrasensitive detection of gelatinase-producing bacteria, with phenotypic AST validated using Staphylococcus aureus (S. aureus) as the model pathogen. Peptide-DNA probes were designed to respond to gelatinase secreted by bacteria remain metabolically active following antibiotic exposure. Bacterial gelatinase cleaves peptides to release initiator single-stranded DNA (ssDNA), triggering hybridization chain reaction (HCR) amplification in micropillar-structured microchannels. Through streptavidin-biotin interaction, poly-horseradish peroxidase (poly-HRP) is anchored in the channel to catalyze luminol based CL. This biosensor achieves high specificity and sensitivity, with a detection limit of 15 CFU/mL, which is better or comparable to previously reported biosensors. Moreover, the potential clinical applicability of this platform is further verified by testing four clinical S. aureus strains against five antibiotics, yielding 95% categorical agreement rate with standard AST methods. The area under the receiver operating characteristic ROC curve (AUC) was 0.944, close to the ideal value of 1, indicating excellent diagnostic performance for AST. The assay time from isolated colonies to AST result takes approximately 4-5 h. Featuring portability and low cost, the platform enables universal bacterial AST, providing a reliable tool for precise antimicrobial therapy and antimicrobial resistance control.

Lanthanide-doped upconversion nanoparticles (UCNPs) due to their unique optical properties are promising for applications ranging from bioimaging to biosensing. However, their practical implementation remains challenging owing to relatively low luminescence efficiency. Herein, we synthesize a series of Ce-doped Yb/Eu/ZnO, Yb/Er/ZnO and Yb/Tm/ZnO UCNPs via a hydrothermal method. Ce ions incorporation promotes anisotropic growth, which increases surface roughness and modulates the local coordination environment. Electrochemical impedance spectroscopy and Tafel plot analyses reveal that Ce doping significantly enhances charge separation and transfer kinetics. Ce ion doping markedly increases the emission intensities of Eu³⁺, Er³⁺ and Tm³⁺, attributed to the formation of Yb³⁺ dimers and efficient energy transfer under 980 nm excitation. Benefiting from these improvements, the Ce-doped ZnO UCNPs exhibit three distinct bio-applications: (i) superior low-temperature optical thermometry with a maximum relative sensitivity of 4.81% K^-1 at 80 K; (ii) excellent antibacterial activity against S. aureus and E. coli (up to 82.16% and 87.64% inhibition at 8 mol% Ce); and (iii) successful employment as luminescent probes in a multiplex immunoassay for the cardiac markers BNP (detection range 10-100 pg/mL) and ST2 (5-25 ng/mL), with high specificity and sensitivity. These findings underscore the potential of Ce-doped ZnO UCNPs as multifunctional platforms for optical thermometry, antibacterial therapy and biomedical diagnostics.

The restricted conversion of low-concentration CO₂ in industrial flue gas and the structural degradation inherent in traditional defect engineering remain key challenges in piezocatalysis. In this work, highly crystalline Co-substituted MgAl-LDH nanosheets were constructed via isomorphous substitution. The atomic-level incorporation breaks the structural centrosymmetry through local lattice distortion. Consequently, it bolsters the piezoelectric built-in electric field to accelerate charge carrier separation. Simultaneously, the Co active sites optimize the interfacial d-band center, strengthen the specific adsorption of CO₂, and substantially lower the energy barrier for the rate-determining step (^⁎COOH formation). The strong coupling between the polarization-induced electric field and interfacial reaction kinetics lets 5% Co-MgAl-LDH outperform pristine MgAl-LDH by roughly 5.7-fold. At 25 °C under a 10% CO₂ atmosphere, 5%Co-MgAl-LDH achieves CO and H₂ production rates of 5542.8 and 3266.2 μmol g^-1 h^-1, respectively, corresponding to a CO/H₂ molar ratio of approximately 1.7:1. Together, local lattice distortion and interfacial electronic-state modulation account for this performance within an otherwise highly crystalline framework, pointing to a workable route for catalysts aimed at low-concentration CO₂ conversion.