Polypropylene (PP) is a state-of-the-art dielectric material for capacitor films owing to its high breakdown strength, excellent processability, and intrinsic self-healing capability. However, its low energy density and poor thermal stability limit its application in next-generation power electronics. Here, a physical blending strategy is developed by incorporating a highly polar, electron-deficient molecule-2-(2,4-Dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine (DBDT)-into PP via extrusion casting. DBDT, owing to its high electron affinity, serves as an effective charge-trapping agent under elevated electric fields and temperatures, thereby significantly suppressing leakage currents while enhancing both breakdown strength and thermal stability. In addition, DBDT functions as a heterogeneous nucleating agent, facilitating crystal refinement and enhanced crystallinity, which collectively contribute to improved mechanical strength. The incorporation of polar DBDT enhances dipolar polarization, thereby increasing the dielectric permittivity. These synergistic effects yield significantly improved energy storage performance. At an optimized DBDT loading of 0.50 wt%, the composite film delivers a high discharged energy density of 5.87 J/cm3 at 650 MV/m, coupled with a discharge efficiency exceeding 87%. This study demonstrates a scalable, physically driven strategy to concurrently tailor crystallization behavior and dielectric performance in PP films, offering a promising design paradigm for highperformance, thermally stable polymer dielectrics.

Interconnected devices, characterized by intelligence, portability, and adaptability, have garnered substantial attention and are progressively being integrated into internet of things (IoT) technology to foster innovation and improve human-machine interaction interfaces. This study presents a polymer-based flexible keyboard that utilizes the piezoelectric effect of poly(vinylidene fluoride) (PVDF). The device is equipped with an array of flexible electrodes, with a thickness of merely 0.13 mm, enabling the press units to respond within 50 ms. Notably, it demonstrates exceptional flexibility and adhesiveness, allowing it to be attached to any desired surface without signal crosstalk. Moreover, the sensitivity and sensing performance of this keyboard device can be further enhanced through encapsulation techniques, rendering it highly suitable for low-frequency trigger scenarios such as device interaction.

Polypropylene (PP)-based dielectric films suffer from low energy-storage density and poor thermal stability, limiting their application in advanced power electronics operating at elevated temperatures. Here, we propose a molecular-trap engineering strategy to simultaneously enhance the dielectric performance, thermal reliability, and processability of PP. A polar voltage-stabilizing molecule, 4-(allyloxy)-2-hydroxybenzophenone (AOHBP), is incorporated into the PP matrix via a scalable melt-blending process, forming deep charge traps in the amorphous regions that effectively suppress carrier migration and leakage current. Meanwhile, weak interactions between AOHBP and PP chains induce a "chain-pinning effect," improving matrix rigidity and restricting segmental motion at high temperatures. The optimized PP/AOHBP-2 film achieves a breakdown strength of 802 MV m-1 and an ultrahigh discharged energy density of 9.16 J cm-3 with an efficiency over 90% at 25 °C, while maintaining 5.33 J cm-3 and 88.3% efficiency at 120 °C. Enhanced cycling stability, power density, and self-healing capability are also realized. This work provides a scalable molecular design paradigm for high-performance PP-based dielectric films with exceptional energy-storage capability and thermal endurance for next-generation film capacitors.

Polypropylene (PP) is renowned for its high crystallinity, low cost, and excellent compliance characteristics, but its low polarity restricts its use in power electronics. Overcoming the trade-off between crystallinity and polarization antagonism in polypropylene (PP) dielectrics represents a critical challenge for advancing high discharge efficiency capacitive energy storage. In an innovative departure from conventional methodologies, we report a molecular-level high entropy engineering protocol that constructs a gradient polar interface within a polypropylene-graft-benzyl acrylate (PP-g-BA) system. This entropy-stabilized microstructure effectively suppresses the formation of conducting pathways by controlling crystalline domain size and orientation, while the graduated polarity profile enables efficient charge injection blocking and dipole alignment. Arising from this synergistic mechanism, the optimized material achieves an unparalleled discharge energy density of 7.5 J cm-3 at 700 MV m-1 with superior efficiency retention over 95%, outperforming all previously reported PP-based dielectrics at equivalent efficiency. This work underscores the transformative potential of entropy-driven design in breaking traditional property trade-offs in polymer dielectrics for next-generation energy storage capacitors.

Modulating interfacial ion transport via separator engineering is pivotal for overcoming the rate capability and cycle life limitations of lithium metal batteries (LMBs). Although polarity-tuning strategies have been widely explored, a clear physical linkage between molecular-level design and transport kinetics, particularly as quantified by Sand's time, remains unresolved, making separator optimization largely empirical. Herein, we report a systematic series of isoreticular covalent organic frameworks (COFs) that decouple pore topology from electronic effects and introduce framework electronegativity (χ) as a quantitative descriptor for ion-selective transport. By modulating χ, exemplified through progressive fluorination, a push-pull electrostatic microenvironment is established that promotes Li+ transport while repelling PF6-, thereby suppressing concentration polarization and revealing an effective scaling relationship between χ and Sand's time. Guided by this descriptor, an optimized TFCOF@PP separator increases the Li+ transference number by 73% and markedly suppresses concentration polarization, enabling stable cycling of LiFePO4 full cells at 5 C with 83.1% capacity retention after 4000 cycles. The system further demonstrates robust performance under demanding conditions, including high-voltage NCM811 cells, elevated temperatures (60 °C), and mechanical abuse. This work elucidates the physical origin linking framework electronegativity to interfacial transport kinetics, providing a rational, descriptor-based strategy for separator design to mitigate kinetic failure in metal batteries.

The coupling effects of radiation and corrosion should be well understood for future deployments of advanced nuclear reactors in both fission and fusion systems. Radiation is often found to accelerate corrosion of metals in aqueous solutions during long-term exposure. However, radiation may also be utilized to improve corrosion resistance of materials if applied appropriately. In this work, we irradiated Mo with Nb+ at a beam energy of 400 keV and a fluence of 4 × 1016 ions/cm2 and observed a significant improvement in corrosion resistance in 3.5 wt.% NaCl aqueous solution. We attribute the enhancement in corrosion resistance to both chemical and structural modifications at Mo surface. Chemically, alloying Mo with Nb near surface, as revealed by DFT simulations and thermodynamic calculations, enhances the adsorption of O compared to Mo alone. This thermodynamically favored Nb-O interaction is expected to lead to the formation of stable Nb/Mo oxides. The presence of such mixed or multi-oxide layers enhances protectiveness of the overall passivation layers. Structurally, Nb+ irradiation induces a population of defects near Mo surface due to irradiation damage. These defects, serving as preferential nucleation sites for oxide formation, enhance the passivation ability of Mo by facilitating the kinetics process of passive film formation, leading to improved corrosion resistance. Our work provides insights into the synergistic effects of irradiation and corrosion, showing how irradiation can be exploited to enhance corrosion resistance of metals through both chemical and structural modifications.

Polypropylene (PP), as a canonical semicrystalline dielectric polymer, suffers from intrinsic structural and electrical weaknesses in its amorphous regions, which limit its performance in high-voltage, high-power electronic applications. To overcome...

High frequency, broadband ultrasonic transducers are pivotal for precise superficial vascular imaging and pathological diagnosis due to their superior spatial resolution. Achieving high frequency detection fundamentally necessitates reducing the piezoelectric layer thickness to the micrometer scale. For ultrathin ferroelectric polymers, this physical scaling significantly amplifies the "surface dead layer" effect, where inherent low crystallinity and disordered dipole orientation severely suppress polarization switching, resulting in a drastic deterioration of device sensitivity. To resolve the trade-off between thickness and performance, we propose a synergistic enhancement strategy combining plasma surface modification with Curie temperature gradient polarization (CT-GP). Plasma treatment is employed to introduce polar functional groups to reactivate the inert surface layer, while the CT-GP process leverages the cooperative effects of thermal activation and electric fields near the Curie temperature to induce robust molecular chain rearrangement and domain stabilization. The β phase crystallinity of the 5 μm-thick film is elevated to 33.01%, with a piezoelectric coefficient (d33) of 20.6 pC N-1. Focused transducers fabricated from these optimized films exhibit outstanding acoustic performance, characterized by a center frequency of 39.5 MHz and a -6 dB bandwidth of 54 MHz. The high signal-to-noise ratio (19 dB) in vivo imaging of murine microvasculature was successfully demonstrated, achieving lateral resolutions of 39.4 μm. This work elucidates the physical mechanism by which surface layers limit the performance of ultrathin films and provides a new theoretical and technical pathway for the development of high-resolution vascular imaging and flexible acoustic devices.

Flexible piezoelectric sensors offer excellent wearability and easy integration, making them attractive for smart devices and health monitoring. However, their low piezoelectric coefficient (d(33)) limits widespread use. In this study, surface-coated barium titanate nanoparticles (mBT) with a core-shell structure were synthesized and incorporated into P(VDF-TrFE) to form composite films. The film containing 10 wt % mBT showed a dielectric constant of 20 at 10(3) Hz, a 31% increase in residual polarization (7.82 mu C & centerdot;cm(-2)), a 30% reduction in coercive field (40 MV/m), and a 58% enhancement in quasi-static d(33) (41 pC/N) compared with the pure polymer. These improvements arise from enhanced interfacial interactions and phase compatibility due to the mBT core-shell design, which promotes beta-phase formation in the polymer matrix. A flexible sensor fabricated from the optimized composite displayed superior pressure sensitivity and linearity (R-2 > 0.999). Its dynamic d(33) and voltage coefficient (g(33)) reached 42 pC/N and 244 mV & centerdot;m/N, improving by 66% and 35%, respectively. The sensor accurately detected low-frequency vibrations (0.5-50 Hz), highlighting the potential of core-shell nanoparticle modification for developing high-sensitivity, low-frequency flexible piezoelectric sensors.

Polymer dielectric films with high energy storage density and efficiency are urgently needed for electric vehicles and power electronics. However, commercial dielectric films often suffer from increased energy loss and leakage current at elevated temperatures, which substantially compromises their energy density and efficiency. Herein, a C-F bond activation strategy was adopted to successfully graft poly(glycidyl methacrylate) (PGMA) segments onto the side chains of poly(tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride), significantly enhancing its high-temperature energy storage performance. The polar groups in PGMA enhance dipole polarization and thus dielectric constant of material. Meanwhile, epoxy groups form a crosslinked network during hot-pressing, which synergistically improves the mechanical modulus and breakdown strength. Combined density functional theory calculations and thermally stimulated depolarization current analysis confirm that PGMA acts as deep traps to effectively capture carriers, suppressing leakage current and enhancing insulation performance. As a result, the graft copolymer with 4.5 wt % PGMA achieves a discharge energy density of 10.0 J/cm3 and a charge-discharge efficiency of 82.1% at room temperature under 600 MV/m. Notably, it retains a discharge energy density of 8.1 J/cm3 and an efficiency of 71.9% at 125 degrees C and 500 MV/m. This work not only provides a theoretical foundation for designing high-temperature-resistant and high-energy-density polymer dielectrics but also proposes an innovative material modification approach.

This study systematically unraveled the structure-property relationships governing polymer materials under cryogenic conditions, specifically dissecting the distinct roles of unsaturated bonds and epoxy groups in determining mechanical integrity. Guided by a rational molecular design strategy, two novel citrate ester derivatives—CA-DB (featuring unsaturated bonds) and CA-EG (bearing epoxy moieties)—were synthesized via a facile two-step protocol. These functionalized plasticizers were subsequently integrated into a poly(vinyl chloride) (PVC) matrix to fabricate composite films, followed by a comprehensive evaluation of their thermomechanical and structural properties. Their influence on tensile strength, elongation at break, migration resistance, and low-temperature performance was systematically evaluated against an unmodified PVC control. The results showed that compared to pure PVC film,CA-DB/PVC and CA-EG/PVC increased elongation at break by 514.49% and 387.41%, respectively. Secondly, in migration tests, CA-EG/PVC exhibited 3.78% lower mass loss in ethanol and 24.26% lower loss in petroleum ether compared to CA-DB/PVC. Furthermore, low-temperature in-situ Raman spectroscopy revealed that CA-DB/PVC retained compatibility without crystallization or phase separation even at –60 °C. Molecular simulations indicated that both functional groups enhance overall composite performance, with epoxy groups playing a particularly key role in improving low-temperature toughness and migration resistance. This work establishes a robust theoretical framework and offers a rational molecular design paradigm for the development of high-performance, sustainable cryogenic plasticizers, thereby enabling the reliable deployment of PVC materials in extreme low-temperature environments.

The rapid emergence of antibiotic-resistant bacteria and biofilm-associated infections has created an urgent need for effective alternatives to conventional antibiotics. Metal-based nanomaterials, such as copper, show promise but are often hindered by poor enrichment efficiency. Here, inspired by the pollen-collection mechanism of bees, we report copper nanoflowers (CuFs) with high enrichment efficiency at room temperature within one-step. Their petal-like micro-nano structures provide a large surface area and strong electrostatic adsorption, facilitating bacterial capture and insertion into the bacterial membrane, thereby leading to an excessive copper environment within the bacteria and up to 99.98% bactericidal efficiency against multidrug-resistant strains. Transcriptomic sequencing and subsequent validation experiments confirmed that the elevated copper levels induced oxidative stress and copper mediated death. Furthermore, their hierarchical structure enables efficient bacterial enrichment, consequently disrupting and eradicating mature biofilms. Successfully integrated into protective masks, the CuFs provide excellent reusability and sustained protection. This practical utility underscores that the hierarchical, contact-active design itself establishes a universal blueprint for engineering next-generation antimicrobial surfaces in precision biomedicine.

Polymer dielectric films that exhibit a high energy density and discharge efficiency are of great importance for advanced electronic and electrical systems. However, achieving a simultaneous enhancement in both the dielectric constant and breakdown strength to attain excellent energy storage performance at elevated temperatures remains a significant challenge. Herein, poly(methyl methacrylate) (PMMA) side chains containing polar groups were successfully grafted onto ethylene-tetrafluoroethylene copolymer (ETFE) via a photocatalytic C-F bond activation strategy. The incorporation of polar groups not only increases the dielectric constant of the graft copolymer but also creates trap sites that hinder charge carrier mobility, thereby suppressing the leakage current and enhancing breakdown strength. As a result, the graft copolymer (optimized at 7 wt % PMMA) achieves a discharge energy density of 6.4 J/cm3, along with a discharge efficiency of 87%. Moreover, the material retains excellent thermal stability at elevated temperatures, exhibiting a discharge energy density of 6.6 J/cm3 and an efficiency of 84% even at 100 °C. This work provides a feasible strategy for modifying high-temperature-resistant fluoropolymers to achieve superior energy storage performance, offering valuable insights for the development of polymer dielectric materials.

A π-extended nonbenzenoid perylene (Pery-56) was constructed via a ring-fusion strategy at both its bay and peri positions. As a result, it features a moderately lower bandgap, broad visible-NIR absorption (525-950 nm) with λmax around 700 nm and reversible redox behavior; the corresponding cationic and anionic radical species were thoroughly studied.

Lithium-sulfur batteries (LSBs) deliver exceptional theoretical specific capacities yet suffer severe practical restrictions from polysulfide shuttling and lithium dendrite growth. Although metal-organic frameworks (MOFs) are popular separator modifiers for LSBs, they rarely integrate efficient polysulfide adsorption/catalysis with uniform lithium-ion conduction. Herein, redox-active dithiothreitol (DTT) is grafted onto the inner metal sites of MIL-101(Cr) channels to fabricate functional polypropylene (PP) separators. On the cathode side, DTT cooperates with the MOF scaffold to immobilize polysulfides, where thiol moieties streamline their redox transformation. Meanwhile, grafted DTT installs abundant lithiophilic -SH and -OH polar sites across the MOF interior. Coupled with size sieving from regular MOF pores, these sites equalize Li+ flux, trigger steady lithium nucleation/deposition, and effectively suppressed the growth of lithium dendrites. Enabled by dual cathode-anode interfacial modulation, this coating clearly elevates battery capacity and cyclability: Li‖Li batteries sustain stable cycling beyond 1000 h, and LSB initial discharge capacity at 0.1C rises from 999 to 1201 mAh g-1. This universal grafting route can incorporate organosulfur active sites into diverse mesoporous MOFs, with promising extensions to metal anode protection, potassium-sulfur batteries, and general electrocatalysis.

Functionalizing isotactic polypropylene (iPP) typically disrupts its molecular regularity and suppresses crystallinity, a persistent trade-off that has constrained its advanced applications. To overcome this limitation, this study systematically investigates how fluorination and processing conditions can be synergistically employed to steer crystallization rather than impede it. Specifically, trifluoroethyl methacrylate (TFEMA) was grafted onto iPP, and the resulting films were prepared via both hot pressing and melt extrusion to comparatively elucidate the interplay between fluorinated groups and processing-induced orientation fields. The incorporation of fluorine, known for its high electronegativity and small atomic radius, suppresses mesophase formation, enhances chain alignment and crystal nucleation, and lowers the energy barrier for molecular rearrangement, thus preserving isotactic regularity during functionalization. The resulting TFEMA-grafted iPP exhibits a 5 degrees C increase in crystallization temperature, a 2% reduction in kinetic barrier (to 5.69 eV), and achieves a record crystallinity approximately 60% at a crystallization temperature around 124.5 degrees C. This study resolves the long-standing conflict between functionalization and crystallinity in iPP, opening a viable route to high-performance iPP for advanced electronics and providing new insight into how fluorine regulates polymer crystallization behavior.

Since the discovery of Chichibabin hydrocarbon in 1907, its scaffold has been instrumental in designing diverse open-shell materials. However, synthetic efforts have yielded almost exclusively symmetric diradicaloids; asymmetric variants with two distinct radical centers remain elusive due to the challenge of forming two different radicals simultaneously. Herein, starting from SOMO-HOMO inversion radicals (2a and 2b) bearing polychlorinated trityl and triarylamine scaffolds, asymmetric Chichibabin diradicaloids (2a+·[SbF6]- and 2b+·[SbF6]-) were successfully obtained through one-electron oxidation for the first time. Their structures were unequivocally confirmed by single-crystal X-ray diffraction, along with EPR and DFT calculations. Owing to their asymmetric architectures with both carbon- and nitrogen-centered radicals, they result in mixed-valence systems displaying broad NIR absorption (949-1105 nm). Furthermore, they serve as efficient redox-active materials in NIR electrochromic devices. This work outlines an effective synthetic route to asymmetric diradicaloids from SOMO-HOMO inversion radicals, and further points toward potential strategies for preparing high-spin species and push-pull-type electron-distributed optical open-shell materials.

This article presents a humidity sensor based on a microporous metal-organic framework (MOF) KAUST- 7. A series of sensing-test experiments were performed, and the results demonstrated that the sensor has promising sensing performance with fast response-recovery speed (6/12 s), high linearity ( $R<^>{2} = 0.992$ ), and good stability in a wide relative humidity (RH) range. Most notably, the microporous structure and fluorine clusters play a supporting role in the adsorption-desorption process of water molecules. The humidity sensing mechanism was analyzed by complex impedance spectrum (CIS) and theory calculation. These results indicated that microporous KAUST-7 is a potential candidate for constructing a humidity sensor with high performance.

Chemically stable interfaces in electrodes are indispensable for maintaining the robust electrochemical interphase evolution to ensure long-term cycling stability of lithium-ion batteries. However, the potential impact on interfacial chemistry by residual protons in association with carboxyl and hydroxyl groups in water-soluble binders (e.g., PAA, CMC/SBR), which are inevitably introduced during the slurry-casting fabrication of electrodes, has received limited attention. Herein, we uncover that the chemically reactive protons trigger ethylene carbonate ring-opening reactions, thereby disrupting the solid electrolyte interphase (SEI) formation and stability, ultimately degrading battery performance. Building on this new insight, a chemically stable, deprotonated electrode (DE) featuring much reinforced interfaces arising from heterogeneous carbon-oxygen covalent bonds is developed, which enables stronger chemical anchoring than the hydrogen bond interactions by carboxyl and hydroxyl groups. In addition, the thus-developed oxygen-rich deprotonated interface reshapes the formation of an inner Li2O-dominated SEI. This deprotonation approach demonstrates broad compatibility with several anode active materials, including microsized SiO, Si, graphite, and their composites. For example, DEs with 86 wt·% SiO/graphite and 80 wt·% 5 μm-sized Si deliver 5.14 mAh·cm-2 over 500 cycles and 4.32 mAh·cm-2 over 200 cycles, respectively. With the new DEs, two Ah-level cells paired with LiNi0.6Co0.2Mn0.2O2 and LiNi0.8Co0.1Mn0.2 cathodes achieve the respective gravimetric energy densities of 288 Wh·kg-1 and 424 Wh·kg-1, while maintaining the capacity retention of 81% over 300 and 78% over 600 cycles. The present work reveals the deprotonation-driven interphase stability mechanism and establishes active-component regulation as a new paradigm for high-energy density lithium-ion batteries.

ABSTRACT Owing to their excellent electromechanical (EM) response, poly(vinylidene fluoride‐trifluoroethylene) (P(VDF‐TrFE))–based ferroelectric polymers (FEPs) are extensively utilized in soft actuators. Currently, the strain ( S 33 ) of FEPs is mostly identified as electrostriction and described by S 33 = Q 33 P 2 . Wherein, Q 33 represents the electrostriction coefficient, P is polarization, and Q 33 is mainly derived from data fitting. However, this approach fails to establish a connection between the composition and structure of FEPs, hindering the design of FEPs with higher EM response performance. This study introduces an effective model that quantitatively correlates the structural parameter interplanar spacing ( d ) to the EM response, namely Q 33 = 100(Δ d / d 0 +1) × Q 33(s) , where d 0 = 4.31 Å, Q 33(s) = −0.54 m 4 /C 2 are from single P(VDF‐TrFE). Guided by this model, we tailored the electrical properties and d of FEPs by incorporating 1,5‐Dihydroxy‐2,2,3,3,4,4‐Hexafluoropentane (HFPD), which results in a substantial improvement in the S 33 by up to 100%. The composite films show promising application in fabricating high‐performance soft robots, including a biomimetic crawler (with a ultra‐fast crawling speeds of 27 cm/s) and a biomimetic butterfly (with a thrust‐to‐weight ratio of 0.71). Overall, our findings offer new insights for designing FEPs with superior EM responses, potentially driving notable advancements in flexible actuators.