Physics

The electrocatalytic reduction of CO2 to multicarbon (C2+) products can be boosted through regulating the proton supply. This promotes *CO hydrogenation and subsequent C–C coupling through enabling the activation and dissociation of H2O. However, this process has often been overlooked, as it may also cause the unfavorable hydrogen evolution reaction. Herein, we present a proton-regulation strategy by introducing Sm(OH)3 on CuOx as an active site for water dissociation to supply protons, thereby enabling efficient conversion of CO2 into C2+ compounds. The constructed 2.4%-Sm(OH)3/CuOx exhibits a faradaic efficiency as high as 84.3% for C2+ production, with an absolute partial current density of up to 627.5 mA cm–2 at −0.77 V versus the reversible hydrogen electrode. Combined experimental results and density functional theory calculations show that the incorporation of appropriate amounts of Sm(OH)3 enhances the interaction between the interfacial H2O and the catalyst, thereby promoting H2O dissociation to generate protons. This process facilitates the hydrogenation of *CO intermediates to *CHO and subsequent C–C coupling via *CHO–CHO, thus enhancing the formation of C2+ products. This work provides insight into the tuning of interfacial H2O dissociation for CO2 conversion.

Abstract In response to the problems of strong heterogeneity of nodes, complex functional dependencies, and insufficient depiction of the impact of systematic failures by traditional assessment methods in the combat system network, this paper proposes a method for evaluating node importance and identifying key nodes by combining the failure propagation model and the network flow blockage theory. Firstly, a directed heterogeneous network model including five types of functional nodes (reconnaissance, command and control, attack, performance enhancement support, and essential support) was constructed, and the resource input and output interfaces and functional dependency paths of each type of node were clarified. Secondly, an improved threshold propagation mechanism was introduced to simulate the diffusion effect of node failures, and a comprehensive influence calculation function based on propagation probability, neighbor overlap degree, and topological KHC index was established. Further, by integrating the maximum flow-minimum cut principle, a propagation-efficiency-coupled key node identification algorithm was designed to depict the weakening effect of node failures on network functional traffic. Through simulation experiments under various failure scenarios and network structures, the results show that compared with traditional centrality indicators, this method has significant advantages in accurately identifying nodes with systematic high-performance loss, and the identification results are more operable and task-chain focused, with good topological adaptability and robustness. The research results can provide theoretical basis and algorithm support for vulnerability analysis of combat networks, anti-destruction design of command systems, and path deduction of suppression.

Abstract Swimming bacteria move through a fluid by actuating their moving body parts. They are force-free and can be described as hydrodynamic force dipoles: pushers or pullers. This modelling description is broadly used in biological physics and active matter research, and it has successfully predicted, for example, the superfluid behaviour of suspensions of pushers or the bend instability and emergence of turbulent flows in active nematics. However, this description accounts only for the translational motion of the swimming body and neglects the effects of hydrodynamic torque dipoles, which are relevant to bacteria with rotary motor-driven flagella, such as swimming Escherichia coli . Here we show that the torque dipole of confined swimming E. coli can power the persistent rotation of symmetric discs. The torque dipole leads to a traction force on the discs, an additive mechanism that is both contactless and independent of the orientation of the bacteria. Our results indicate that the torque dipole of swimming E. coli is notable in confined geometries, which is relevant to bacterial transport through porous materials, biofilms and the development of chiral fluids.

Symmetrically branched metal nanostructures with intricate structural features and exceptional physicochemical properties demonstrate a significant potential for diverse applications. Nevertheless, achieving precise morphological control over these nanostructures with adjustable dimensions poses a considerable challenge, especially for stellated icosahedrons (STICs) with 20 orderly arranged branches. Here, we present a template replication strategy for the controllable synthesis of metal STICs with various compositions, featuring high yield, uniformity, and adjustable dimensions. The synthesis relies on fine-tuning the reduction kinetics toward heterogeneous nucleation and growth through optimizing the reduction potential of the metal precursors. Notably, the synthesized Au STICs exhibit tunable localized surface plasmon resonances and scattering spectra by varying their sizes as well as profound surface-enhanced Raman scattering (SERS) activity. Electron energy-loss spectroscopy and numerical simulations confirm the symmetrical distribution of their surface plasmon resonances, enabling the polarization-angle-dependent SERS enhancement. Moreover, the resulting magnetic Ni-NiPx STICs exhibit chain-like self-assembly under magnetic fields. This work offers an approach to the rational synthesis of branched nanostructures with complex and intricate architectures that hold significant promise for applications in SERS and catalysis.

Tellurium (Te) is increasingly gaining attention as a scalable p-type channel material owing to its inherently high carrier mobility and ambient stability. However, in sub-5 nm Te channels, high contact resistance remains a major obstacle to achieving high-performance device operation. In this study, an estimated contact resistance of ≈1.7 kΩ·μm is obtained in 4 nm-thick Te channels by engineering the band structure in the source and drain (S/D) regions using a raised source and drain (RSD) structure. To isolate intrinsic contact behavior, electrical measurements are conducted at 77 K, in which thermally activated defect states are suppressed, and carrier injection is dominated by the metal-semiconductor interface. Transport characterization reveals a more than 17-fold increase in on-state current and a more than 50-fold reduction in contact resistance relative to Te devices without the RSD structure. This enhancement is attributed to selectively increasing the Te thickness at the S/D terminals, which tunes the bandgap by thickness-dependent modulation. The resulting RSD architecture enhances tunneling current by narrowing the barrier width─modulated by gate bias. This scalable, low-temperature approach offers broad applicability to other ultrathin channel materials.

Cell engagers have emerged as a promising approach for cancer immunotherapy, yet their efficacy is often limited by structural constraints in antibody valency and spatial configuration. Here, we present a DNA origami-based platform for the precise spatial organization of antibodies, enabling the construction of tailored multivalent cell engagers to enhance antitumor immunity. By modulating the composition, valency, and spatial arrangement of antibodies on a single DNA origami scaffold at the single-molecule level, we developed two types of cell engagers, T cell engagers and natural killer cell engagers, that effectively activate immune cells and improve tumor specificity. In vitro studies demonstrated that both engagers elicited specific and effective immune responses against epidermal growth factor receptor (EGFR)-expressing tumors. Furthermore, in vivo studies using murine solid tumor models validated the efficacy of both engagers in inhibiting tumor growth. This study demonstrates the potential of DNA origami as a versatile and programmable platform for engineering precision immunotherapies and highlights its utility for targeted tumor eradication.

The efficient accumulation and uniform distribution of nanomedicine within tumors are critical for achieving therapeutic outcomes. However, conventional medical imaging technologies struggle to efficiently and accurately detect nanoparticles (NPs) distribution, especially in resolving their cellular-level spatial heterogeneity. Existing deep-learning-based predictive models focus on tumor cell density and vascular distribution but do not address the complex spatial relationship between cancer-associated fibroblasts (CAFs) and drug distribution. This study presents NanoNet, a deep-learning framework that leverages fibroblast activation protein (FAP) immunostaining to spatially characterize CAFs and predict NPs distribution at high resolution. NanoNet achieved high predictive accuracy (ICC = 0.963, R2 = 0.9849) by transforming tumor section images into pixel-level NPs distribution maps. The FAP channel contributed substantially to predictive accuracy, indicating its important role in guiding NPs behavior. This study provides a spatially resolved predictive framework that enables pixel-level predictions of NPs distribution from conventional histological sections, with potential applications for optimizing nanomedicine design and personalized nanomedicine.

The heat capacity of amorphous carbon, a fundamental yet elusive property, is pivotal for its thermal applications, but it lacks a predictive model across its vast density spectrum. Here, large-scale neuroevolution potential molecular dynamics simulations show a pronounced nonmonotonic dependence. Across 1.1–4.0 g cm–3, the volumetric heat capacity (CV) first increases in the low- and medium-density regimes but surprisingly decreases upon further densification in the high-density regime. This reversal is associated with a fundamental crossover in governing physics: CV is initially controlled by atomic densification (void collapse), then modulated by phonon softening during the sp2-to-sp3 transition, and ultimately dominated by phonon stiffening (blueshift in the phonon density of states (PDOS)) under high pressure, which overrides the density effect. Phonon dispersion analysis directly visualizes this mechanistic shift, correlating it with the structural evolution from graphitic networks to diamond-like structures. This work provides a quantitative, regime-specific framework that decouples the competing roles of density and PDOS, providing a fundamental basis for the rational design of amorphous carbon in advanced thermal management.

Long-range moiré patterns in twisted WSe2 enable a built-in, moiré-length-scale ferroelectric polarization that can be directly harnessed in electronic devices. Such a built-in ferroic landscape offers compelling means to enable ultralow-voltage and non-volatile electronic functionality in two-dimensional (2D) materials; however, achieving stable polarization control without charge trapping has remained a persistent challenge. Here, we demonstrate a moiré-engineered ferroelectric field-effect transistor (FeFET) utilizing twisted WSe2 bilayers that leverage atomically clean van der Waals interfaces to achieve efficient polarization–channel coupling and trap-suppressed, ultralow-voltage operation (subthreshold swing of 64 mV dec–1). The device exhibits a stable non-volatile memory window of 0.10 V and high mobility, exceeding the performance of previously reported 2D FeFET and matching that of advanced silicon-based devices. In addition, capacitance–voltage spectroscopy, corroborated by self-consistent Landau–Ginzburg–Devonshire modeling, indicates ultrafast ferroelectric switching (∼0.5 μs). These results establish moiré-engineered ferroelectricity as a practical and scalable route toward ultraclean, low-power, and non-volatile 2D electronics, bridging atomistic lattice engineering with functional device architectures for next-generation memory and logic technologies.

While perovskite-based devices have been widely investigated, achieving scalable production of monocrystalline perovskite heterojunction films with high interfacial quality through in situ growth methods remains challenging, primarily due to inherent lattice incompatibility and pronounced anion migration issues. Here, we report the successful growth of a monocrystalline 0D/3D perovskite heterojunction film with an area of 6.25 cm2 via a vapor-phase epitaxy technique. The structural compatibility between the 0D and 3D perovskite components results in heterojunction films with well-defined interfaces, exceptional crystallinity, and high uniformity, showing oriented growth along the (001) and (011) crystal facets. This heterojunction system facilitates the reconstruction of an asymmetric space-charge distribution and enables the dynamic passivation of halide vacancies in the 3D component, thereby enhancing electric field modulation and defect passivation. As expected, the resulting single-crystalline 3D/0D heterojunction film-based photodetector demonstrates superior performance at zero bias, with a high responsivity of 85.56 A·W–1, a large detectivity of 1.80 × 1012 Jones, and rapid photoresponse times (τrise = 8.15 μs, τdecay = 21.32 μs). By incorporating the monocrystalline heterojunction film within a pixelated array architecture, real-time imaging with high-contrast is achieved. This work offers a comprehensive method for fabricating high-quality perovskite monocrystalline heterojunction films for self-powered photodetectors.

Sodium metal batteries (SMBs) are promising candidates for next-generation energy storage systems due to their high energy density and abundant sodium resources. However, their application is hindered by sluggish interfacial kinetics at low temperatures. We designed a temperature-dependent electrolyte by balancing ion–dipole and dipole–dipole interactions. The electron-withdrawing effect of fluorine (F) atoms increases the instability of the fluoroethylene carbonate (FEC) dipole orientation within the solvation shell. As temperature decreases, FEC’s dipole reorientation triggers a shift from an ethyl methyl carbonate (EMC)-dominated solvation structure to an FEC-dominated one. This significantly reduces the desolvation energy of solvent-separated ion pairs (SSIPs), contact ion pairs (CIPs), and aggregates (AGGs), accelerating interfacial kinetics. It also reorganizes the solvation structure and alters the decomposition pathway of the electrolyte, forming a thin, organic-rich CEI layer at low temperatures. As a result, P2-Na2/3Ni1/3Mn2/3O2 (P2-NNMO) and O3-NaNi1/3Fe1/3Mn1/3O2 (O3-NFM) cells demonstrate reliable performance, achieving a high-capacity retention of 92.4% after 1000 (1 C) and 84.7% after 900 (0.5 C) cycles at −20 °C. Notably, the P2-NNMO and O3-NFM cells deliver reversible discharge capacities of 80.6 and 102.3 mAh g–1 at −40 °C, respectively. This work offers valuable insight for advancing energy storage technologies.

ABSTRACT Osteoarthritis (OA) progression is driven by inflammation, oxidative stress, and mechanical wear. However, current therapies are often limited in efficacy due to poor biocompatible functional materials and the inability to deliver drugs on demand in the pathological joint. Herein, we developed a triple‐responsive, nanostructured injectable hydrogel (Cur/GP‐HA) to OA joint microenvironment for synergistic treatment. The Cur/GP‐HA hydrogel was formed by cross‐linking hyaluronic acid (HA) with curcumin (Cur)‐preloaded, phenylboronic acid‐modified generation 3 poly(amidoamine) dendrimers, utilizing the dynamic covalent chemistry between diols on HA and PBA under a physiological pH. This hydrogel exhibited a 3D porous network with excellent injectability and self‐healing ability, enabling intelligent Cur release in response to low pH, high reactive oxygen species (ROS) generation, or mechanical compression. Importantly, the constructed Cur/GP‐HA hydrogel removed ROS, promoted the polarization of macrophages, and regulated cytokine secretion to reshape the anti‐inflammatory microenvironment. In vivo, intra‐articular injection of Cur/GP‐HA hydrogel significantly reduced cartilage erosion, alleviated joint inflammation, and improved subchondral bone integrity. In addition, the synergistic combination of HA lubrication and sustained Cur release provided chondroprotection and anti‐wear effects. This work proposes an intelligent injectable hydrogel integrating antioxidant, immunomodulatory, and mechano‐responsive protective functions, providing a promising new strategy for OA treatment.

ABSTRACT Developing flexible, self‐sufficient power generators is of significance for burgeoning wearable electronics. Biofuel cells (BFC) that harness perspiration metabolites can potentially offer a promising route toward simultaneous energy generation and self‐powered sensing. However, insufficient power supply and susceptible enzyme‐induced instability hinder widespread adoption. Herein, an enzyme‐free hybrid glucose BFC is designed employing nitrogen‐phosphorus doped carbon (NPC) flexible film derived from self‐assembly graphene/polymer hydrogels, incorporating platinum nanoparticles for glucose oxidation and manganese dioxide‐based O 2 ‐independent capacitive cathode. The O 2 ‐independent design eliminates potential interference to the anodic reaction, enabling a markedly enhanced maximum power density of 680 µW cm −2 and an open circuit voltage of 0.92 V, alongside operational stability exceeding 30 days. When functioning as the self‐powered glucose sensor, it offers a wide range of 0.05–20 mM. Integrated into a conformal wearable system, the device enables bioenergy harvesting from human sweat and real‐time glucose monitoring via compact signal processing electronics. This work underscores the potential of flexible hybrid BFC systems and paves the way for powering next‐generation wearable bioelectronics in personalized healthcare.

ABSTRACT Aqueous sodium‐ion hybrid capacitors (ASIHCs) represent a promising sodium‐based energy storage technology owing to their cost‐effectiveness and high‐power characteristics, yet they face practical implementation barriers from performance degradation at subzero temperatures and energy density limitations imposed by capacitive electrodes. Herein we demonstrate a zwitterionic polymer containing paired cationic/anionic groups (─N + (CH 3 ) 2 /─SO 3 – ) that simultaneously regulates hydrogen‐bond networks and establishes rapid Na + transport channels through selective ion interaction. This strategy yields a zwitterionic hydrogel electrolyte (PASGE) exhibiting a low freezing point (−36°C), exceptional ionic conductivity (58.6 and 12.4 mS cm – 1 at 25 and −20°C, respectively), superior water retention, widened electrochemical stability window (ESW), and mechanical robustness. We further assemble a new ASIHC configuration by pairing a pseudocapacitive δ‐MnO 2 cathode with a pre‐sodiated carbon‐coated NaTi 2 (PO 4 ) 3 anode (δ‐MnO 2 ||PASGE|| pre‐sodiated NTP/C, labeled as MNHC). Benefiting from the high ionic conductivity and large ESW of PASGE, δ‐MnO 2 maximizes its pseudocapacitive behavior, achieving specific capacity comparable to the NTP/C anode (>100 mAh g −1 at 0.3 A g −1 ). Ultimately, our MNHC demonstrates high operating voltage (2.3 V), excellent foldability across −20 to 65°C, and superior energy densities (>58.0 Wh kg – 1 at both 25 and −20°C), surpassing many ASIHCs and even typical aqueous sodium‐ion batteries.

ABSTRACT As a critical stage in chronic liver disease, liver fibrosis can progress to irreversible damage without timely intervention. Stem cell therapy offers significant therapeutic potential owing to its potent regenerative and immunomodulatory properties. However, its clinical application is challenged by low cell survival, poor targeting, and inadequate paracrine regulation. Here, we present a magnetic hydrogel patch laden with human umbilical cord‐derived mesenchymal stem cells (hUC‐MSCs) to enhance their antifibrotic efficacy via synergistic magneto‐mechanical stimulation. The patch is fabricated through thiol‐ene “click” chemistry using multi‐thiol‐functionalized magnetic nanoparticles as crosslinkers. Molecular dynamics simulations reveal the regulatory mechanism of nanoparticle concentration on the crosslinking topology of the hydrogel network, thereby identifying the optimal formulation with favorable mechanical properties and magnetic responsiveness. Under magneto‐mechanical stimulation, the resulting patch significantly enhances the secretion of key antifibrotic factors from hUC‐MSCs by activating the PI3K/Akt/mTOR signaling pathway. Moreover, in vitro and in vivo results demonstrate that, under magnetic stimulation, the hUC‐MSC‐laden magnetic patch significantly inhibits hepatic stellate cell activation, promotes anti‐inflammatory macrophage polarization, reduces collagen deposition, and ameliorates the inflammatory microenvironment, thereby effectively reversing liver fibrosis. This study offers a versatile stem cell‐based platform for spatiotemporally controlled therapy of liver fibrosis and potentially other fibrotic diseases.

ABSTRACT Crystals with layered features, by virtue of their intrinsic structural asymmetry, exhibit pronounced optical anisotropy, positioning them as leading candidates for high‐performance birefringent materials. Although numerous crystals with layered features exhibiting giant birefringence (Δ n ) have been experimentally reported, a comprehensive understanding of their theoretical limits, modulation mechanisms, and structure‐property relationships remains lacking. Herein, we integrate high‐throughput screening with first‐principles calculations to investigate 131 experimentally stable candidates, constructing an empirical band gap‐birefringence Pareto frontier. Our analysis reveals that giant birefringence originates from synergistic macroscopic and microscopic mechanisms. Macroscopically, a universal “volcano‐type” dependence on the packing factor ( η ) identifies an optimal geometric dilution at η ≈ 0.5. Microscopically, “covalent locking” enforces strict electron confinement within the two‐dimensional plane, thereby maximizing the polarization difference. This work establishes universal design principles, transitioning the exploration of birefringent crystals from trial‐and‐error to rational geometric and electronic engineering.

Abstract This paper develops a physics-based and accurate shallow trench isolation lateral double-diffused MOS (STI-LDMOS) compact subcircuit model. In the proposed direct-current (DC) model, the drift-region resistances beneath both the shallow trench isolation (STI) region and the drain electrode are incorporated, thereby significantly improving its physical fidelity and predictive accuracy of the DC characteristics. For the proposed alternating-current (AC) model, the gate–drain capacitance model is decomposed into two components: a gate–drift-region overlap charge model with modified bias dependence derived from BSIM4.5, and a parallel-plate capacitance model for the gate–STI overlap region. In addition, the gate–source capacitance and drain–source charge models are further extended to match the physical structure and to more accurately capture the dynamic characteristics of an STI-LDMOS device. The model parameters are extracted and calibrated, and the proposed subcircuit model is implemented in Verilog-A. Excellent agreement is achieved between the proposed model and both the TCAD simulation results and the measured data from a 40 V STI-LDMOS device, demonstrating its accuracy and efficiency for circuit-level simulation of STI-LDMOS devices.

An analytical compact model is developed for the mobile charge density of multiple-channel field-effect transistors based on the III-nitride material system. Two-dimensional electron and hole gases can be potentially induced by spontaneous and piezoelectric polarization in polar heterostructures. Focusing on the active region of devices that employ a multiple quantum-well layout, the total electron and hole populations are estimated from fundamental electrostatic and quantum mechanical principles. Hole gas depletion techniques, revolving around intentional donor doping, are modeled and evaluated, culminating in a generalized closed-form equation for the mobile carrier density across the doping schemes examined. The utility of this model is illustrated by exploring AlGaN/GaN, AlInN/GaN, and AlScN/GaN heterostructures. The compact framework provided herein considerably elucidates and enhances the efficiency of multi-layered transistor design.