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Flexoelectric-stabilized hierarchical polar bubbles in wrinkled ferroelectric CuInP2S6
The realization of complex, high-order topological textures in ferroelectrics typically relies on demanding epitaxial growth under substrate clamping. Here, we report hierarchical polar bubbles in the van der Waals ferroelectric CuInP2S6, enabled by a facile wrinkle-induced strain-engineering strategy. Vector piezoresponse force microscopy reveals that localized wrinkled bulges generate large strain gradients, which activate a flexoelectric-assisted polarization reversal and form a macroscopic polar envelope. This macro-bubble encapsulates pre-existing intrinsic ferroelectric nanodomains, resulting in a distinctive nested bubble-in-a-bubble hierarchical architecture. Statistical analysis indicates that the formation probability decreases with increasing flake thickness, providing strong evidence for a strain-gradient-dominated flexoelectric origin. Real-time in situ manipulation demonstrates the mechanical recoverability of these hierarchical states under external loading. This work introduces a novel form of ferroelectric topology and establishes a mechanical pathway for designing resilient functional elements for next-generation straintronic devices.
Spin-state regulation-enhanced piezoelectric-polarization-driven catalytic kinetics in 1T-dominant MoS2
1T-dominant MoS2, owing to its relatively high electrical conductivity, facilitates charge transport induced by piezoelectric polarization; however, the reaction kinetics are still constrained by rapid charge-carrier recombination. In this work, a 1T-dominant MoS2 piezocatalytic system was constructed, and Fe was introduced to regulate the local electronic structure and magnetic-related characteristics. Magnetic measurements reveal that Fe doping effectively tunes the effective magnetic moment of the material. Under ultrasonic excitation, compared with pristine MoS2, high-spin 10% Fe-MoS2 exhibits markedly enhanced piezocatalytic kinetics (approximately a 200% increase in the reaction rate), enabling second-level degradation of rhodamine B while maintaining excellent structural stability before and after the reaction. These results demonstrate a close correlation between the regulation of magnetic-related properties and piezoelectric-polarization-driven catalytic behavior, providing a new physical perspective for tuning carrier dynamics in mechanically driven catalytic systems.
Color‐Fidelity Stepwise Charge‐Transfer Modulation Enables Highly Efficient BT.2020‐Compliant Deep‐Blue OLEDs
ABSTRACT Achieving deep‐blue organic emitters that combine high efficiency with the strict color purity required for the BT.2020 display standard remains one of the most persistent challenges in organic electronics. A key limitation arises from the difficulty of reconciling narrow emission with efficient harvesting of both singlet and triplet excitons. Here, we introduce a color‐fidelity stepwise charge‐transfer modulation strategy sequentially strengthens short‐range and long‐range charge‐transfer pathways, suppresses vibrational coupling to narrow the emission spectrum, and simultaneously reduces the singlet–triplet energy gap while enhancing spin–orbit interactions to accelerate the spin‐flip process. Guided by this design principle, the optimized emitter ( BOCz‐CzPO ) achieves a markedly increased reverse intersystem crossing rate (12.5 × 10 3 s −1 ) and a near unity photoluminescence quantum yield. When incorporated into organic light‐emitting diodes, BOCz‐CzPO delivers one of the highest external quantum efficiencies (28.0%) among deep‐blue OLEDs based on mono‐boron MR frameworks with CIE y values close to the BT.2020 target, exhibiting Commission Internationale de l’Éclairage chromaticity coordinates of (0.146, 0.052) and approaching the BT.2020 deep‐blue specification.
Hardware edge detection system based on a self-assembled vertically aligned ferroelectric memristor
Real-time image processing faces significant challenges in traditional von Neumann systems due to data transfer bottlenecks between the processor and memory. Neuromorphic computing offers a promising alternative. This study introduces a self-assembled, vertically aligned ferroelectric memristor based on Ba0.6Sr0.4TiO3:(ZrO2)0.92(Y2O3)0.08 (BST:YSZ) for electronic synaptic functions. The memristor demonstrates stable, tunable resistance states that effectively mimic synaptic behavior. Using its neuromorphic architecture, we developed an image edge detection system. The system's output closely matches simulation results, achieving a mean square error of 3.88, a peak signal-to-noise ratio of 27.88 dB, and a structural similarity index of 0.97, indicating high computational accuracy. These findings highlight the potential of ferroelectric memristors for neuromorphic edge computing, particularly in real-time image processing applications.
One‐Dimensional Polycyclic Aromatic Hydrocarbons Incorporating Multiple Dithiafulvene Units—Novel Multi‐Redox and Electrochromic Systems
ABSTRACT The combination of polycyclic aromatic hydrocarbons (PAHs) and dithiafulvene (DTF) units provides large π‐conjugated scaffolds with multi‐redox behavior. Here, we present the synthesis and properties of PAHs containing seven or nine alternating and fused six‐ and five‐membered rings and three or four DTF units located along the PAHs, tri‐DTF and tetra‐DTF PAH scaffolds. The synthesis relied on the generation of PAH cores with carbonyl groups at the five‐membered rings to allow for Horner–Wadsworth–Emmons reactions to introduce the DTF units. These planar molecules exhibited very strong associations in neutral and oxidized states, and the various redox states had distinct UV–vis–NIR absorptions. Proceeding from an odd number to an even number of DTF units had a remarkable consequence for the redox properties. Thus, cyclic voltammetry revealed the tri‐DTF PAH to undergo stepwise one‐electron oxidations to form the trication with a broadened first oxidation wave owing to associations. Instead, the radical cation of the tetra‐DTF PAH underwent a single three‐electron oxidation, signaling an exceptional driving force for generating the tetracation. By electrocrystallization both mixed‐valence neutral–radical cation and radical cation salts were generated. These multi‐DTF PAHs are particularly interesting as potential components for electrochromic and conducting materials or as redox‐controllable tectons for molecular self‐/disassembly.
Ferroelectric switchable magnon valley and nonlinear Hall effect in type-I multiferroics
Electric control of magnetism at room temperature is crucial for developing next-generation high-performance spintronics. However, the intrinsic incompatibility between ferroelectricity and magnetism in crystal symmetry, along with the absence of strong magnetoelectric coupling mechanisms, continues to pose major challenges. In this work, we propose a general theoretical framework for magnon manipulation based on ferroelectric polarization switching in two-dimensional multiferroics. Our results demonstrate that, in monolayer hexagonal multiferroics, ferroelectric switching can significantly modulate the intralayer spin exchanges, enabling nonvolatile ferroelectric control of magnons. More importantly, ferroelectric polarization reversal leads to a sign change in the Berry curvature, ensuring effective control over the valley and nonlinear Hall response of magnons. Combining density functional theory calculations, we further identify a class of material candidates with Curie temperatures near room temperature. Our results provide a new way toward low-power and ferroelectrically controllable spintronics.
Multidentate Molecular Suturing at Dual Interfaces Enables Highly Efficient Perovskite Light‐Emitting Diodes
ABSTRACT Perovskite light‐emitting diodes (PeLEDs) have emerged as a promising technology for future displays owing to their prominent optoelectronic properties. However, inefficient charge injection and nonradiative recombination at the interfaces, alongside defective crystal growth, remain the primary bottlenecks for efficient LED devices. Herein, we propose a “molecular suturing” strategy that synchronously stabilizes the interface and directs crystal growth using a multifunctional ligand. We employ methyl bis(2,2,2‐trifluoroethyl) phosphonoacetate (MBTPA), which features cooperative carbonyl (C = O), phosphoryl (P = O), and trifluoromethyl (─CF 3 ) groups. The C = O and P = O groups chemically bind to defect sites, forming coordination interactions with undercoordinated Pb 2+ and halide vacancies. Concurrently, the ─CF 3 moieties establish robust hydrogen‐bond interactions with hole injection layer. By providing these two complementary interactions on opposite sides, MBTPA effectively “sutures” the buried interface between the perovskite and the hole‐transport layer, strengthening interfacial adhesion and promoting more efficient hole injection. Consequently, MBTPA‐modified PeLEDs achieve bright blue emission at 485 nm with a peak external quantum efficiency (EQE) of 23.14%, and green emission at 513 nm with a peak EQE of 27.05%. This molecular suturing strategy provides an effective route for simultaneous control of interfacial chemistry and crystallization, offering a generalizable approach for performance enhancement in perovskite optoelectronic devices.
Digitally programmable kirigami metamaterials via magnetic encoding
The vast configuration space of magnetic metamaterials, enabled by embedding reversibly orientable magnets into rotating-square kirigami pixels, remains largely unexplored beyond uniform magnetization patterns. To navigate this space, in-plane magnetic orientations are treated as binary bits, creating 2N×N possible states for an N×N lattice. A Monte Carlo approach, combined with a mapping of all configurations onto an N2-dimensional hypercube, allows for the systematic statistical enumeration of energy landscapes and single-bit reconfiguration paths. This framework classifies stability into neutral, monostable, bistable, and tristable classes, with occurrence probabilities converging to approximately 0, 0.6013, 0.3981, and 0.0006 as system size increases. Programmable responses—including tension–compression asymmetric stiffness, snap-through instability, and a two-stage absorption/locking energy dissipation mode—are demonstrated. The resulting digital, graph-based platform points to applications in soft modular robotics, impact-mitigation layers, deployable structures, and mechanical logic.
Multiferroic Orders and Piezoelectric Sensing in an Organic‐Inorganic Bismuth Halide
ABSTRACT Multiple ferroic orders integrated into a single material pose great potential for next‐generation sensing, memory and switching devices. Organic‐inorganic hybrid materials (OIHMs) have emerged as promising candidates due to their synergistic combination of functional organic cations and inorganic frameworks. However, obtaining multiferroic materials has long been a continuous challenge, and bismuth‐based OIHM multiferroics remain a blank to date. Here, we report a multiferroic OIHM (DMPA) 3 Bi 2 Br 9 (DMPA = N,N ‐dimethylisopropylamine), which couples ferroelectric and ferroelastic properties for the first time among bismuth‐based OIHMs. Driven by dynamic cation reorientation, (DMPA) 3 Bi 2 Br 9 undergoes multiple symmetry‐breaking processes, enabling m F m ‐type ferroelectric and 3 m F m ‐type multiferroic phase transitions as well as exceptional four‐state SHG transition behaviors. Benefiting from these attributes, (DMPA) 3 Bi 2 Br 9 crystals achieve a notable piezoelectric coefficient d 33 of 35 pC/N, enabling its flexible composite with polyurethane to show excellent piezoelectric sensing responses for pose recognition. This work not only expands the family of multiferroic materials but also underscores their promise for next‐generation flexible electronics and switching devices.
Optical isolator based on a subwavelength integrated optical metawaveguide
Dielectric metawaveguides that leverage the resonant behavior of individual dielectric scatterers have recently been suggested as a versatile platform for controlling light propagation and tailoring light–matter interactions in integrated optical circuits. Their broad tunability is of particular interest for the realization of various reconfigurable optical elements. Here, we propose an approach for realizing optical isolation based on a metawaveguide composed of silicon nanoparticles exhibiting a predominant in-plane electric dipole response. We show that perturbation of the metawaveguide geometry leads to the formation of modes with a non-zero transverse optical spin through the mode coupling mechanism. Furthermore, by incorporating magnetic material into the waveguide, we demonstrate a compact optical isolator compatible with the silicon-on-insulator platform and provide a general framework for its design. Our results have significant implications for the advancement of high-density photonic circuits and may enable functionalities in directional emission, optical communications, and sensing technologies.
Structural Insights Into CO <sub>2</sub> Transport Pathways in a W‐Formate Dehydrogenase: Structural Basis for CO <sub>2</sub> Reduction
ABSTRACT Mo/W‐dependent formate dehydrogenases (Fdhs) catalyze the reversible reduction of CO 2 to formate and are key biocatalysts with high potential for CO 2 capture/conversion technologies. Although previous studies have suggested the presence of two substrate‐access tunnels in Fdhs, experimental evidence for CO 2 ‐specific pathways has been lacking. Here, we present an integrated study of Nitratidesulfovibrio vulgaris FdhAB combining crystallography, molecular dynamics simulations, mutagenesis, and kinetic assays. Nv FdhAB crystals pressurized with Kr, O 2 , and CO 2 were used to map gas diffusion routes and uncovered a substrate‐retention site consistently occupied by small molecules in multiple crystal structures. Our results indicate that both substrates mostly use the main tunnel to reach this retention site, but H 2 O and CO 2 can also enter through a novel side branch before following a shared route to the buried W active site. The retention site, located at the junction of both tunnels, plays a synergistic role in enhancing CO 2 reduction by increasing substrate concentration near the catalytic center, thereby improving catalytic efficiency. Notably, variants affecting this site showed a selective effect for CO 2 reduction, with no impact on formate oxidation. These findings provide experimental evidence of a CO 2 ‐specific pathway and identify structural determinants underpinning efficient CO 2 reduction in this enzyme family.
Straintronic nanomagnetic computing
One method of electric field control of magnetization is to generate a strain in a piezoelectric layer by applying an electric field to it and transfer this strain to a magnetostrictive nanoscale magnet or to the magnetostrictive soft layer of a magnetic tunnel junction deposited on the piezoelectric, thus controlling its magnetization state through inverse magnetostriction (Villari effect). Such strain-mediated electric field control of magnetization offers an extremely energy-efficient method of writing the magnetic state (∼100 aJ/bit). This review discusses the development of computing paradigms based on strain control of magnetism, termed “straintronics” or “magnetic straintronics,” and their future potential. Here, we discuss various Boolean memory and logic devices as well as non-Boolean and neuromorphic computing devices proposed and experimentally demonstrated along with their potential advantages and key challenges.
Anion‐Controlled Structural Interconversion of Palladium Cages Enables Separations by Selective Guest Capture and Release
ABSTRACT Self‐assembled host–guest systems provide a powerful platform for molecular recognition and binding. Achieving the controlled and selective release of bound guests remains challenging, typically relying on destructive stimuli. Herein, we report that asymmetric ligand L assembles to form an interconverting pair of palladium(II)‐based metal–organic cages, Pd 4 L 8 (BF 4 ) 8 and Pd 6 L 12 (NTf 2 ) 12 , capable of undergoing clean, reversible, and quantitative structural interconversion triggered by specific counter‐anions. The two cages exhibit distinct guest recognition profiles, with each cage binding a different subset of guests. We use anion‐mediated structural transformations to achieve orthogonal, multi‐cycle, selective binding and release of different guest molecules under mild conditions. To showcase the power of this supramolecular catch‐and‐release purification, we designed and validated a closed‐loop purification process, successfully isolating Darunavir from a complex mixture of pharmaceutical molecules with exceptional selectivity and efficiency. This work highlights a broadly applicable strategy for advanced molecular separations and selective pharmaceutical purification.
Interfacial Sr diffusion stabilized (Ca,Sr)TaO3 thin film and its semiconducting behaviors
Perovskite-structured materials host enormous phases such as superconductivity, ferromagnetism, and ferroelectricity, which largely rely on the states of transition metal octahedra. Compared to the extensively studied 3d-orbital perovskite, heavier elements (such as Ta, W, and Ir) with 5d orbitals are of great interest due to their stronger spin–orbital coupling related physics. However, due to the difficulty in synthesis, research on 5d-element perovskite is quite limited. Here, we synthesized tantalate perovskite (Ca,Sr)TaO3 films by pulsed laser deposition. Structural characterizations indicate that the films are epitaxial to the substrates. By tuning the growth parameters such as oxygen partial pressure and growth temperatures, the carrier density can be tuned from ∼1014 to ∼1016 cm−2 while maintaining semiconducting behavior. We found that the interfacial Sr diffusion from the substrate to the film is critical for its structural stabilization. Analogous to KTaO3, our synthesis of (Ca,Sr)TaO3 perovskite films offers a new platform for the study of interfacial physics.
Brillouin-zone-folded intrinsic chirality tailoring third-harmonic generation in planar metasurface-waveguide systems
Robust chiral resonances with ultrahigh quality factors (Q-factors) and strong circular dichroism (CD) underpin both fundamental studies of optical chirality and emerging chiral photonic technologies. Here, we theoretically propose a paradigmatic strategy for realizing such resonances in planar metasurface-waveguide systems by harnessing Brillouin-zone folding. Using an elliptical-disk dimer metasurface as a representative platform, we show that Brillouin-zone folding combined with in-plane C2 symmetry breaking naturally yields two distinct polarization-selective resonances, namely an x-polarized quasi-guided mode and a y-polarized quasi-bound state in the continuum. When the remaining in-plane mirror symmetry is broken, these orthogonally polarized resonances become simultaneously accessible and coherently hybridize, producing a pronounced chiral mode with a Q-factor approaching 103 and CD of 0.997. Moreover, nonlinear simulations further reveal that this intrinsically chiral resonance provides a powerful handle for tailoring optical nonlinearities, boosting third-harmonic generation to a conversion efficiency of 3.8 × 10−6 under a pump intensity of 1 MW cm−2. Notably, the third-harmonic response is highly spin-selective, exhibiting nearly three orders of magnitude contrast between left- and right-circularly polarized excitation. Our results establish Brillouin-zone folding combined with symmetry engineering as a versatile route to high Q-factor chiral resonances, offering opportunities for chiral photonic applications across both linear and nonlinear domains.
Generation of tripartite entanglement among optical modes in a single multimode nanobeam
We theoretically demonstrate genuine steady-state tripartite entanglement in a monolithic optomechanical nanobeam integrating one transverse electric (TE) and two transverse magnetic (TM) optical modes coupled to a single mechanical mode. The system achieves strong coupling rates of g1/2π≈6.99×105 Hz for the TE mode, and g2,3/2π≈5.92×104 Hz and 4.91×104 Hz for the TM modes, with a mechanical quality factor Qm≈2.15×109, ensuring thermal stability up to 350 mK. Our analysis reveals that while bipartite entanglement persists across various regimes, genuine tripartite entanglement requires strong coupling, confirming the optimal operating point of our design. Telecom-band compatibility at 1549 nm is achieved through width-dependent tuning. Using finite element simulations and quantum Langevin analysis, we identify parameter regimes where the three optical modes exhibit verifiable tripartite entanglement (Rτmin&gt;0), stable under cryogenic conditions with milliwatt-level pump powers.
Salt‐Regulated Confinement of FeO Microcrystallites on Amorphous Mn <sub>3</sub> CoO <sub>x</sub> for Boosting Sustainable Acidic Water Oxidation
ABSTRACT Nanomaterials with amorphous surface have attracted significant attention in the oxygen evolution reaction (OER), which still needs further investigations. In this work, we developed a novel Salt‐regulated confinement loading method to prepare amorphous Mn 3 CoO x support confined FeO microcrystallites at a relatively low‐temperature (623 K). The confined FeO microcrystallites showed strong interfacial electronic interactions with Mn 3 CoO x matrix (abundant defect sites and flexible local environments), enabling efficient charge transfer and enhanced intermediate stabilization for efficient OER in acidic media. The FeO/Mn 3 CoO x exhibits remarkable OER performance, with a low overpotential of 252 mV@10 mA cm −2 with a significantly lower Tafel slope of 79 mV dec −1 , outperforming the commercial IrO 2 (∼ 290 mV@10 mA cm −2 ). Mechanistic studies reveal that the incorporation of FeO microcrystallites, as electron reservoirs to stabilize high‐valence intermediates and facilitate continuous turnover, induces a synergistic transition from a purely lattice oxygen‐mediated mechanism (LOM) to a dual LOM and oxygen pathway mechanism (OPM).These results are well corroborated by in situ attenuated total reflection surface‐enhanced infrared spectroscopy, differential electrochemical mass spectrometry, and density functional theory calculations. Our work provides a robust strategy to design amorphous, non‐precious‐metal OER catalysts capable of stable operation in acidic media, offering a scalable route toward efficient hydrogen production.
Multi-strategy cooperative optimization of thermoelectric performance in higher manganese silicide-based materials
Higher manganese silicide (HMS), a naturally abundant p-type thermoelectric (TE) material, exhibits an eco-friendly profile, low production cost, superior mechanical strength, and high thermal stability. Current strategies for enhancing the TE performance of HMSs focus on optimizing dopants for anionic/cationic substitution and nanocomposite engineering. Nevertheless, the cost-prohibitive nature of requisite dopants and nanocomponents, coupled with intricate synthesis routes, impedes their practical deployment. In this study, V-Al-co-doped HMS bulk specimens incorporated with CrSi2 are consolidated by spark plasma sintering following wet ball milling. This strategy employs dual-site doping, with V substituting at cationic Mn sites and Al at anionic Si sites to achieve acceptor doping, thereby increasing the hole concentration. Concurrently, CrSi2 nanoparticle incorporation enhances phonon scattering at grain boundaries, significantly suppressing lattice thermal conductivity (κl). Furthermore, both V and Cr interact with Mn, respectively, forming resonant states near the Fermi level and ultimately resulting in overlapping of the energy levels. At 823 K, the (Mn0.985V0.015) (Si0.99Al0.01)1.79 + 20% CrSi2 composite achieved a peak zT value of 0.72, a 71.4% enhancement over the pristine MnSi1.79 matrix. Consequently, synergistic cation–anion site engineering coupled with nanostructured composite design provides an effective strategy for enhancing the TE performance of HMSs, leveraging defect-mediated carrier optimization and phonon scattering intensification.
CD44‐Assisted Transcytosable Chimeras for Extracellular Protein Depletion in Deep Tumors
ABSTRACT Extracellular targeted protein degradation (eTPD) typically uses antibody‐derived bifunctional chimeras to direct extracellular targets toward lysosomal degradation. However, the requirements for antibody modification complicate degrader design, and their large size hinders tissue penetration. While small‐molecule degraders provide enhanced tissue permeability, they suffer from poor pharmacokinetics and a limited target scope. Here we develop CD44‐Assisted Transcytosable CHimeras (CATCHs), a plug‐and‐play platform that leverages CD44‐mediated transcytosis for extracellular protein depletion in deep tumors. CATCHs are built on a hyaluronan‐containing nanoparticle chassis, functionalized with IgG‐affinitive tags to recruit unmodified antibodies. This design enables rapid generation of CATCHs against diverse targets. We show that CATCHs can drive near‐complete depletion of cell‐surface proteins, including PD‐L1 and HER2, within 3 h at single‐digit nanomolar antibody concentrations. Mechanistic studies reveal that CATCHs remove target proteins in a CD44‐dependent manner through not only lysosomal proteolysis but also transcytosis of protein targets into extracellular spaces. The transcytosis‐inducing activity also allows CATCHs to penetrate deep tumor tissues via consecutive transcytosis and effectuate depletion in otherwise inaccessible regions. We show that PD‐L1‐targeting CATCHs could induce potent antitumor immunity by depleting PD‐L1 throughout tumor tissues. This platform promises a versatile eTPD tool with implications for both biomedical research and therapeutic drug discovery.
Time-domain electrical heating for broad-range and anisotropic thermophysical characterization of semiconductors
As transistor scaling approaches physical limits, the accurate quantification of thermal conductivity and interfacial thermal conductance for semiconductor materials within chips has emerged as a critical bottleneck for next-generation integrated-circuit design and thermal management. Existing thermal measurement techniques are challenged by devices exhibiting concurrent high thermal conductivity, multilayer structures, and pronounced anisotropy, often requiring complex procedures, prolonged measurement times, and multi-method integration—yet still yielding unsatisfactory accuracy. To overcome these limitations, we propose a time-domain electrical heating (TDEH) method that enables simultaneous high-resolution characterization of out-of-plane and in-plane thermal conductivity as well as heat capacity. The TDEH method was validated across a broad thermal conductivity range (1–4000 W/(m K)), showing excellent agreement between the measured thermal conductivity, heat capacity, and other standard references. Furthermore, the successful application of TDEH to both strongly anisotropic low-thermal-conductivity Ga2O3 thin films and polycrystalline diamond demonstrates its versatility for comprehensive thermal characterization of semiconductor materials. Our work provides a versatile, high-precision, and easily implementable solution for chip's thermal characterization, offering an essential tool for thermal management design in high-power and highly integrated chips.