Efficient hydrolysis of robust chemical bonds under mild conditions remains a central challenge in catalysis and biomass valorization. Herein, we report a zirconium single-atom nanozyme anchored on nitrogen-doped carbon (Zr-NC) that exhibits remarkable catalytic activity toward the hydrolysis of beta-1,4-glycosidic bonds. The Zr-N4 coordination environment endows the isolated Zr centers with pronounced Lewis acidity, enabling effective polarization and activation of glycosidic bonds under ambient conditions. Using PNPG as a model substrate, Zr-NC demonstrates significantly enhanced hydrolytic activity compared to conventional zirconium oxide catalysts. Density functional theory (DFT) calculations reveal that the strong Lewis acidic character of the Zr-N4 site facilitates charge redistribution within the glycosidic bond, lowering the activation barrier for nucleophilic attack by water. Moreover, the single-atom configuration suppresses excessive water coordination, maintaining an optimal balance between substrate adsorption and catalytic turnover. As a result, Zr-NC enables efficient depolymerization of cellulose-rich biomass, achieving effective degradation of corn stover under mild conditions. This work highlights the potential of single-atom nanozymes as robust and tunable Lewis acid catalysts for biomass conversion and sustainable catalysis.

Optimizing semiconductor charge-carrier dynamics is pivotal for boosting device performance, yet the lack of spatiotemporal-resolved characterization methods forces iterative device fabrication to realize such optimization. Here, we develop transient spectroscopic imaging (TSI) techniques, combining local transient photoluminescence and transient absorption microscopy, to directly visualize intra- and intergrain carrier dynamics and guide the micronano-scale interface optimization of devices. Using TSI, we study 4-fluorobenzoyl amide (FBA)-passivated two-dimensional (2D) BA2PbI4 perovskite films, revealing that FBA passivation suppresses intragrain and intergrain carrier recombination behavior and elevates the intragrain diffusion coefficient (D) from 1.1 × 104 to 1.9 × 104 nm2 ns-1 and the diffusion length from 181.7 to 477.5 nm, respectively. Correspondingly, FBA-passivated photodetectors (PDs) exhibit exceptional performance, achieving a responsivity of 39.0 A W-1 under 9.9 nW cm-2 illumination (meeting weak-light detection criteria ≤ 0.1 μW cm-2) and a linear dynamic range of 139.2 dB, ranking among the best 2D Ruddlesden-Popper perovskite PDs. For the first time, integrating this PD into a single-pixel imaging system enables high-fidelity image reconstruction and recognition via correlation and compressive sensing algorithms. This work establishes a robust platform for carrier dynamics analysis, deepens the mechanistic understanding of PD operation, and expands the application of 2D perovskite devices in image recognition.

ABSTRACT Routine screening and longitudinal surveillance of hepatocellular carcinoma (HCC) require sensitive, on‐site analytical methods. Lateral flow immunoassays (LFAs) enable large‐scale screening but lack intrinsic signal amplification. Although nanozymes can enhance LFA readouts, their amplification remains constrained by inefficient hydrogen peroxide (H 2 O 2 ) activation. Herein, an electronically coupled Au/PtIr trimetallic nanozyme (Au/PtIr NPs) is constructed by decorating Au nanoparticle (Au NP) surfaces with island‐like PtIr alloy nanodomains. This architecture forms spatially adjacent dual‐site adsorption interfaces with heterogeneous electronic properties. Alloy‐induced interfacial electronic modulation synergistically optimizes H 2 O 2 adsorption and facilitates its homolytic O─O bond, selectively enhancing •OH generation and accelerating peroxidase‐like (POD‐like) catalytic kinetics. Integrated into an LFA platform, Au/PtIr NPs enable sensitive and reliable detection of α‐fetoprotein (AFP) in clinical samples, with a linear response from 0.2–1000 ng mL −1 and a limit of detection (LOD) of 57.7 pg mL −1 , which is 390‐fold lower than that of conventional Au NP‐based LFAs. The assay shows good agreement with clinical reference methods. The electronically regulated Au/PtIr interface maintains reliable amplification in complex biological matrices. Coupled with a simplified readout workflow, it enables minimally instrumented point‐of‐care detection. This electronic‐interface engineering approach provides a generalizable route to catalytic signal amplification for LFA‐based diagnostics.

Weak-light detectors exhibiting long-term stability are of significant importance for both national defense and civilian applications. To address this, we fabricated a lateral high-performance photodetector (PD) based on a poly(N-vinylcarbazole) (PVK)-passivated 2D (PMA)(2)MAPb(2)I(7) perovskite. The PVK passivation significantly improved both device performance and stability by suppressing vacancy formation and restricting grain boundary migration. The passivated PD achieved a nearly eightfold improvement in self-powered responsivity (R = 0.25 A & centerdot;W-1, D* = 2.5 & times; 10(11) Jones) and a sixfold enhancement under 5.0 V bias (R = 10.28 A & centerdot;W-1, D* = 2.6 & times; 10(12) Jones) in comparison with those of the pristine counterpart, showing a high performance compared to the other PDs based on perovskite materials. The passivated PD in self-powered mode demonstrated exceptional operational stability by maintaining 80.7% of its initial photocurrent over 1000 h in ambient air. Integrated into a custom optical communication system, this PD enabled reliable data transmission, while also delivering high-quality imaging under weak illumination (0.1 mu W cm(-2)). This work provided a valuable design strategy for high-performance PDs, translating device innovations into practical solutions for self-powered, weak-light applications critical to emergency scenarios.

Hydroquinone, catechol, and resorcinol are dihydroxybenzene isomers that commonly occur in phenolic contaminants in water. Their analogous structures and near-identical oxidation potentials cause severe overlap in electrochemical signals, leading to poor identification accuracy. We report a nanozyme-amplified electrochemical fingerprinting strategy for machine-learning-assisted discrimination of these isomers. The sensing interface is built on a cooperative nanozyme comprising copper single atoms and copper nanoclusters supported on a graphene/graphdiyne framework (i.e., Cu SA/Cu NC-GDY/G). Mechanistic studies indicate that the Cu single atoms primarily promote the adsorption and oxidation of phenolic substrates, while the Cu nanoclusters facilitate O2 activation. The conductive GDY/G framework accelerates interfacial electron transfer and stabilizes the catalytic sites. This site-specific synergy enhances laccase-mimetic catalytic oxidation and amplifies subtle differences in the differential pulse voltammetry (DPV) responses of the three isomers. The resulting DPV fingerprints, including peak current, peak potential, and waveform features, were analyzed by linear discriminant analysis (LDA), which enabled successful discrimination of individual isomers, binary and ternary mixtures, and concentration-dependent responses. The platform also showed good repeatability, anti-interference capability, long-term stability, and applicability in spiked tap water, river water, and lake water samples. In summary, this work demonstrates that integrating nanozyme-amplified electrochemical fingerprinting with chemometric analysis provides an effective strategy for recognizing environmental pollutants that are structurally similar.

As a commonly used disinfectant in clinical medicine, glutaraldehyde is highly volatile and possesses a ppb-level environmental permissible threshold. Developing a sensitive and portable gas sensing platform for low-concentration glutaraldehyde detection is crucial. Herein, we present an efficient chemiresistive sensor that enables the low-concentration and rapid detection of glutaraldehyde. The sensor is based on SnO2 nanofibers (NFs) functionalized with bimetallic PtPd nanocatalysts (NCs). Square-shaped PtPd NCs with a uniform edge length of 8.2 nm are synthesized by a hydrothermal method and then introduced into SnO2 NFs. The resulting PtPd-SnO2-1 sensor yields a rapid, sensitive, and reversible response to glutaraldehyde gas, with a theoretical detection limit of 10.7 ppb. The remarkable gas sensing properties are attributed to the sensitization and synergistic effect of PtPd NCs, thereby promoting the formation of chemisorbed oxygen species and enhancing the response. Density functional theory (DFT) results show that the catalytic effect of bimetallic PtPd NCs leads to an increase in adsorption energy as well as charge transfer, and Pd-doping-induced shift of the d-band center. As a key component, the sensor is integrated into a wireless glutaraldehyde sensing platform, which integrates a circuit board and a smart terminal, thus achieving convenient and effective glutaraldehyde detection. The finding indicates that the PtPd-SnO2 sensor is a potential candidate for practical glutaraldehyde detection.

Due to its broad-spectrum sterilization ability, glutaraldehyde is widely used for sterilizing medical devices. However, a certain concentration of glutaraldehyde gas in the air can cause harm to the health of medical staff and patients. Due to the long-chain nature of glutaraldehyde and the interference of humidity in the detection environment, its detection is challenging. In this study, octadecahedral BiVO4 (Octad-BiVO4) with multiple crystal facets was synthesized through crystal facet engineering. Compared with other structures of BiVO4, this structure simultaneously achieved the dual effects of active site enrichment and humidity interference suppression, enabling the Octad-BiVO4 glutaraldehyde gas sensor to exhibit excellent gas sensing performance even under humidity conditions close to those of actual indoor applications. Through XPS, dangling bond calculations and density functional theory calculations, the differences in oxygen vacancies, unsaturated coordinating atoms, and adsorption energy for glutaraldehyde among different crystal facets were revealed. It confirmed the influence of crystal facet engineering on gas sensing performance. Additionally, this work also designed a portable monitoring circuit system for glutaraldehyde, which can not only provide real-time concentration alarms for glutaraldehyde but also transmit information via Bluetooth to the terminal. This work provides a new strategy for detecting trace amounts of glutaraldehyde gas under humid conditions.

The performance of 2D ferroelectric perovskite optoelectronic devices is still severely limited by complex interfacial morphologies and intrinsic semiconducting characteristics, including large exciton binding energies. Here, we present a facile strategy to address these limitations simultaneously by sensitizing 2D ferroelectric perovskite EA4Pb3Br10 films with the conjugated polymer poly(3-hexylthiophene). This modification effectively optimizes carrier dynamics in the active layer by facilitating hot-carrier transport, promoting efficient exciton dissociation, and prolonging carrier recombination. As a result, the device achieves a record self-powered responsivity of 264.7 A W- 1 in ferroelectric perovskite photodetectors, representing a 104-fold enhancement over the pristine counterpart. Concurrently, the device exhibits exceptional low-power photonic synaptic plasticity under small applied biases and can be readily integrated into neural networks for high-precision fingerprint identification, highlighting its considerable promise for low-power neuromorphic computing applications. This work demonstrates the synergistic optimization of perovskite films through conjugated polymer sensitization, paving the way for the development of high-performance 2D ferroelectric perovskite optoelectronics.

Most laccase-mimetic nanozymes fail to replicate the synergistic, division-of-labor catalysis of natural multicopper laccases, limiting activity gains. A key bottleneck lies in the construction of atomically defined and spatially organized active sites that integrate oriented structural motifs with multistate electronic configurations. Here, we report a graphdiyne-derived Cu single-atom/nanocluster nanozyme (CCG) in which the sp-carbon scaffold hierarchically organizes Cu single atoms (SAs) and nanoclusters (NCs) to mimic the asymmetric microenvironment and electronic structure of native laccase active sites. Cu SAs serve as electron transfer centers, while Cu NCs reproduce the oxygen-accepting characteristics of multinuclear Cu sites. Electronic structure analyses reveal that the sp-carbon precisely modulates Cu coordination geometries and spin states, generating tri-site electronic features analogous to the T1/T2/T3 ensemble in natural laccases. Steady-state kinetics reveal that CCG exhibits 5.21-fold higher specific activity than ZmLac3 with enhanced substrate affinity. In salt-stressed maize seedlings, CCG functionally compensated for endogenous ZmLac3 and regulated lignin biosynthesis, increasing root lignin content and cell wall thickness by 27.6% and 47.7%, and improving root activity and biomass by 61.2% under 300 mM NaCl. This study establishes an atomic-precision design paradigm that integrates hierarchical site construction with multistate electronic coordination, guiding the development of next-generation high-performance biomimetic nanozymes.

The kinetics of oxidase-like (OXD-like) nanozymes are significantly influenced by the electronic configuration of their active sites. In this study, a nanozyme that features unique electronic interactions was created by in situ construction of iridium nanoparticles on graphdiyne-coated carbon nanotube (Ir/GDY/CNT). This configuration enables efficient and specific oxygen activation through a spin-state modulation mechanism. The incorporation of sp-hybridized carbon (sp-C) facilitates a transition in the electronic structure of the Ir sites from low-spin to high-spin states via electronic metal-support interactions. This enhances the adsorption strength and electron transfer between the Ir sites and reactants/intermediates, leading to an improved OXD-like activity. The Ir/GDY/CNT nanozyme demonstrates a 6.2-fold enhancement in OXD-like activity compared to pristine iridium nanoparticles, and a 2.5-fold improvement over Ir/CNT. Capitalizing on this improved catalytic performance, a colorimetric sensor was developed for the detection of organophosphorus pesticides. The sensor exhibits a wide linear range (0.1-1200 ng mL-1) and ultralow detection limit (0.03 ng mL-1), outperforming previously reported systems. This work establishes a generalizable strategy for developing high-performance OXD-like nanozymes through spintronics-level engineering, which presents significant potential for environmental and diagnostic applications.

To enhance photodetector performance, transient absorption (TA) microscopy is employed for the first time, to the best of our knowledge, to investigate carrier diffusion in interface-passivated semiconductor polycrystalline films. TA analysis reveals that after passivation with DMMI-Cl, the carrier diffusion length in MASnBr3 polycrystalline films increases from 109 nm to 123 nm, while the diffusion coefficient improves from 0.119 cm2 s-1 to 0.151 cm2 s-1. Furthermore, DMMI-Cl passivation suppresses carrier losses from monomolecular and Auger recombination and promotes bimolecular recombination. The resulting photodetector exhibits a nearly six-fold enhancement in responsivity (R = 4.09 AW-1), giving it a strong standing among reported 3D hybrid Sn-based perovskite photodetectors. This work expands the application scope of TA microscopy, provides deeper insight into grain-boundary-modulated spatiotemporal carrier dynamics, and contributes significantly to the development of high-performance tin-based photodetectors.

In this work, a hollow cubic CuS was synthesized via the etching of Cu2O, followed by the in-situ growth of graphdiyne (GDY) on its surface to yield a CuS/GDY composite nanozyme. The synergistic interaction between CuS and GDY endowed the nanozyme with pronounced peroxidase-like activity, facilitating the oxidation of substrates such as TMB, OPD, and ABTS in the presence of H2O2. Kinetic studies indicated a higher affinity of CuS/GDY for TMB compared to horseradish peroxidase (HRP), with a lower Km value for TMB. Radical scavenging experiments identified hydroxyl radicals (·OH) and singlet oxygen (1O2) as the primary reactive oxygen species (ROS) responsible for the catalytic oxidation. CuS/GDY also exhibited exceptional catalytic degradation of Rhodamine B (Rh B), achieving a degradation rate of 90.5

In the past two decades, nanozymes have garnered increasing interest, however, their catalytic activity and efficacy still lag significantly behind that of natural enzymes, posing limitations on their utility in bioanalytical applications. In this study, we introduced a novel BaTiO3/graphdiyne/Au (BGA) nanozyme that leverages surface plasmon resonance and piezoelectric effects to concurrently respond to light and ultrasound (US) stimulation, resulting in a 3.8-fold enhancement in peroxidase-like activity. Theoretical and experimental findings suggest that US stimulation induces lattice distortion in BaTiO3, leading to the reversible conversion of C---C bonds to C--C bonds in graphdiyne. Consequently, the liberated electrons recombine with the hot holes produced by Au nanoparticles upon light excitation, thereby efficiently inhibiting the recombination of hot electron-hole pairs and substantially augmenting peroxidase-like activity. The BGA nanozyme was further configured as a detection platform for E. coli O157:H7. The sensor exhibited a broad linear range (1-107 CFU mL- 1) and a low limit of detection of 7 CFU mL- 1. Moreover, the sensor exhibited exceptional applicability in the analysis of various real samples such as milk and lemon juice. This study presents a novel research framework for constructing highactivity nanozyme sensors responsive to external fields, offering significant potential in biological analysis, environmental surveillance, and food safety applications.

We developed a transverse photodetector using EA(4)Pb(3)Br(10) films that demonstrates excellent self-powered performance: a responsivity (R) of 0.11 A W-1 and a detectivity (D*) of 1.41 x 10(9) Jones. At 3.0 V bias, performance enhances dramatically (R = 11.40 A W-1, D* = 1.42 x 10(11) Jones). Excitation intensity-dependent transient absorption measurements reveal a carrier diffusion length of similar to 2.90 mu m, accounting for the superior optoelectronic performance. Frequency-modulation tests demonstrate the bias voltage effectively aligns ferroelectric domains, thereby restricting the barrier associated with crystal domains and resulting in significantly faster response times than those under self-powered operation. The implemented encrypted optical communication system operates reliably in power-scarce environments; meanwhile, our single-pixel imaging system, which functions without an external power, is also designed. Both of them are suitable for responding to sudden power outages in emergency scenarios. This work advances the field of high-performance photodetection while expanding practical optoelectronic applications.

The catalytic efficiency of natural enzymes depends on the precise electronic interactions between active centers and cofactors within a three-dimensional (3D) structure. Single-atom nanozymes (SAzymes) attempt to mimic this structure by modifying metal active sites with molecular ligands. However, SAzymes struggle to match the catalytic efficiency of natural enzymes due to constraints in active site proximity, quantity, and the inability to simulate electron transfer processes driven by internal electronic structures of natural enzymes. This study introduces a universal spatial engineering strategy in which molecular ligands are replaced with graphdiyne (GDY) to induce d-π orbital hybridization with copper nanoparticles (Cu NPs), leading to an asymmetric electron-rich distribution along the longitudinal axis that mimics the local electric field of natural laccase. Moreover, multiple sp bonds within GDY scaffold effectively anchor Cu NPs, facilitating the construction of 3D geometric structure similar to that of natural laccase. An enzymatic activity of 82.53 U mg −1 is achieved, 4.72 times higher than that of natural laccase. By reconstructing both 3D structures and local electric fields of natural enzymes through d-π orbital hybridization, this approach enhances electron interactions between cofactors, active centers, and substrates, and offers a versatile framework for biomimetic design of nanozymes.

Polarization single-pixel imaging system, as a rapidly developing imaging technology, has greatly benefited from the in-depth understanding and clarification of the mechanisms behind polarization optoelectronic performance. In this work, a polarized single-pixel imaging system has been developed, comprising a digital micro-mirror device (DMD) and a single-pixel detector based on a Digital Video Disc (DVD) film coated with CsPbBr3 quantum dots, and can recognize images with different polarization characteristics. Finite-Difference Time-Domain (FDTD) simulations and the polarized photoluminescence tests confirmed that the photons entering in the pattern film can exhibit polarization characteristics, under the influence of a dielectric field originating from the periodical pattern structure. The polarization-dependent transient absorption tests simultaneously confirmed that the carrier movement occurring in the patterned CsPbBr3 QDs film exhibits anisotropy. For the first time, the synergistic effect of the periodic dielectric field and carrier movement anisotropy on the polarized photodetector is reported. This provides a novel approach for the design and optimization of polarization single-pixel imaging systems based on periodically patterned nano-structures, which is expected to promote their widespread application in fields such as optoelectronic detection and quantum information processing.

Efficient oxidase-mediated oxidation is pivotal for environmental remediation and energy conversion application, yet natural enzymes require artificial alternatives due to inherent instability. Cofactors are essential in natural oxidase catalysis, interacting with the active centre to induce an electronic 'push effect' that propels the catalytic process. While efforts to mimic cofactors in nanozyme often involve sophisticated designs and complex synthesis. This study presents a scalable material engineering approach to mimic cofactor functionality using platinum nanoparticles (Pt NPs) supported on an ultrathin graphdiyne/graphene (GDY/G) composite (Pt/GDY/G), in which the sp-hybridized carbon (sp-C) in GDY induces a dual electronic 'push effect'. The unique sp-C structure in GDY imparts semiconductor characteristics and a low work function, this induces an interfacial electrostatic potential between GDY and Pt, which enables unidirectional electron transfer from GDY to Pt, thereby enhancing the electron density at Pt sites. Moreover, the sp-C sites in GDY act as oxygen (O2) adsorption centres, forming a spCOO-Pt bridge that facilitates electron transfer from GDY to O2. This sp-C induced dual electronic 'push effect' significantly reduces the energy barrier for OO bond cleavage, resulting in a 3.4-fold enhancement of the oxidase-like (OXD-like) activity of Pt/GDY/G compared to Pt NPs alone. This work provides mechanistic insights into the design of OXD-like nanozymes, offering a promising strategy to boost O2 activation and OO bond cleavage. The superior catalytic performance of Pt/GDY/G highlights its potential for dye and microplastics degradation, contributing to sustainable environmental remediation.

The development of high-performance nanozymes is often hindered by intrinsic activity limitations that restrict biosensing sensitivity. In this study, a black phosphorus/graphdiyne (BP/GDY) heterostructure nanozyme was engineered to overcome these challenges, exhibiting significantly enhanced peroxidase (POD)-like activity under light irradiation. Compared to pristine GDY and BP, the BP/GDY nanozyme demonstrated 11.8-fold and 7.7-fold higher catalytic efficiency, respectively. Mechanistic analysis revealed that this enhancement stems from a light-induced structural transformation in GDY (CC → CC transition), which facilitates electron release and optimizes interfacial charge transfer, thus further amplifying POD-like activity. Leveraging this photo-enhanced catalysis and combining the advantages of enzyme-linked immunosorbent assay (ELISA), a high-specificity nanoprobe (BP/GDY-Ab2) was constructed and integrated with a capture antibody to develop a dual-mode biosensing platform for the detection of Vibrio vulnificus (V. Vulnificus). This platform incorporates both colorimetric (LOD = 4.7 CFU mL-1, linear range: 101-106 CFU mL-1) and photothermal (LOD = 9.4 CFU mL-1, linear range: 101-106 CFU mL-1) signals. The sensor demonstrated high accuracy in detecting V. vulnificus in spiked seafood samples, achieving a rapid response time of 5 min and effectively distinguishing the target pathogen from six interfering bacterial species through spatial charge distribution matching. This study introduces a novel photo-enhanced nanozyme activation strategy, establishing a versatile and scalable platform for on-site food safety monitoring and precision diagnostics, particularly in resource-limited settings.

Traditional design approaches for nanozymes typically rely on empirical methods and trial-and-error, which hampers systematic optimization of their structure and performance, thus limiting the efficiency of developing innovative nanozymes. This study leverages machine learning techniques supported by high-throughput computations to effectively design nanozymes with multi-enzyme activities and to elucidate their reaction mechanisms. Additionally, it investigates the impact of dopants on the microphysical properties of nanozymes. We constructed a machine learning prediction framework tailored for dopant nanozymes exhibiting catalytic activities like to oxidase (OXD) and peroxidase (POD). This framework was used to evaluate key catalytic performance parameters, such as formation energy, density of states (DOS), and adsorption energy, through density functional theory (DFT) calculations. Various machine learning models were employed to predict the effects of different doping element ratios on the catalytic activity and stability of nanozymes. The results indicate that the combination of machine learning with high-throughput computations significantly accelerates the design and optimization of dopant nanozymes, providing an efficient strategy to address the complexities of nanozyme design. This approach not only boosts the efficiency and capability for innovation in material design but also provides a novel theoretical analytical avenue for the development of new functional materials.