Regulating the polymer phase structure at the metal polymer boundary remains a bottleneck in lightweight polymer metal composites (PMCs). Here, we introduce a temperature-gradient-driven heterogeneous-nucleation strategy that in situ engineers the crystalline architecture of nylon 66 (PA66) directly on Ti-6Al-4 V (TC4) during hot pressing. By controlling hot pressed temperature field, we induce a progressive transition from gamma- to alpha-crystal polymorphs of PA66 at the interface, creating an ordered crystalline phase transformation that functions as a mechanically graded transition zone. The resulting interfacial bonding strength reaches 14.56 MPa at 320 degrees C, outperforming conventional bonding protocols by 78%. Failure mode reveals a micropore anchoring plastic pullout failure and plastic-pullout mechanism. XPS confirms the formation of Ti-O-C covalent bonds that chemically anchor the ordered crystalline phase transformation to the oxide-rich TC4 surface, rich in porous structures, provides it with heterogeneous nucleation sites. This thermally directed polymorphic templating approach offers a facile, scalable route toward ultra-reliable PMCs for next-generation lightweight structures.

The development of high-performance carbon materials for electrochemical energy storage has relied on precise control over atomic configurations. However, conventional nitrogen-doping methods typically produced random dopant distributions and mixed configurations, which limited the improvement of electrochemical activity. In this work, we demonstrated that structural defects intrinsically directed the selective incorporation of highly active nitrogen atoms at edge sites of the carbon skeleton, achieving defect-induced precise edge-N (N-5 and N-6) doping. High-power ultrasonication introduced numerous structural defects, mainly new zigzag edges, into the two-dimensional graphene lattice. Multi-scale analyses, from bulk spectroscopies (XPS, EPR) to atomic-resolution EELS mapping, demonstrated that N atoms were concentrated at edge regions, predominantly forming edge-N configurations with the pi*/sigma* ratio nearly 10 times higher than that of the in-plane region. By analyzing the N doping process (up to 600 degrees C), it was found that the healing of carbon structure defects was limited within this temperature range. These defect sites exhibited stronger adsorption toward NH3 than the basal plane proved by density functional theory (DFT) calculations as the energetic basis, and NH3 indeed preferentially attacked defect sites passivated by H or O-containing groups. Consequently, the abundant and persistent defects under 600 degrees C as active sites led to a gradual increase in total nitrogen content while maintaining a high and stable proportion of edge-N (similar to 72%). When the temperature exceeded 600 degrees C, both the overall nitrogen content and the proportion of edge-N decreased. The defect-engineered graphene (sN-C-600) exhibited a 116.8% increase in specific capacitance relative to its undoped counterpart and delivered a 24.9% higher capacitance than the non-defect sample (LN-C-600). Overall, this study established structural defects as active regulators of N heteroatom incorporation, providing design guidance for constructing carbon electrodes with controllable edge chemistry and optimized electrochemical functionality.

Due to complex pathological features and difficulty in healing wounds caused by diabetes, effective therapeutic agents and strategies remain elusive. Herein, we report on the development of Cu-doped single-phase Nb2(Sn0.7Cu0.3)C MAX as a tri-functional therapeutic material for diabetic wound healing. The stable Nb-C lattice facilitates near-infrared plasmonic photothermal therapy, physically disrupting bacterial structures. Controllable Cu2 + release mimics endogenous metal ion signaling, disrupting TCA metabolism to induce bacterial cuproptosis. Meanwhile, Cu2 + also promotes regenerative macrophage phenotype and reduces excessive neutrophil activation. The Nb 4d-C 2p orbital hybridization simulates VEGF functionality to mediate angiogenesis. In vivo experiments demonstrate that Nb2(Sn0.7Cu0.3)C promotes rapid infection clearance, initiating the wound healing process. This is followed by the restoration of immune homeostasis, ultimately leading to effective angiogenesis. Our Nb2(Sn0.7Cu0.3)C overcomes the limitations of single-targeted therapeutic agents, capable of simultaneously addressing issues such as infection control, inflammation resolution, and tissue regeneration.

Plastic-Metal hybrids have gained significant attention in automotive and aerospace fields. In the study, the silane was introduced on the surface of anodized micro-nano porous aluminum alloy (Al) plate. The silanized Al sample was then joined with polybutylene terephthalate (PBT) specimen by ultrasonic-assisted hot pressing technology to manufacture hybrid. The interfacial physical embedding structure plays an important role in plastic-metal joining and the scanning electron microscope (SEM) results demonstrated that effective mechanical interlocking was achieved between PBT and Al. X-ray Photoelectron Spectroscopy (XPS) results demonstrated the new chemical bonds occurred at the PBT-Al interface, which acted as bridges in the PBT-Al interface joining. Due to synergistic effect of physical embedding and chemical bonding, the maximum adhesion strength reached 36.3 MPa when the silane concentration was 4 %, which was 37 % higher than that without silane treatment. When the silane concentration exceeds 4 %, leading to blocking pores on the anodized aluminum alloy surface, resulting in a decrease in adhesion strength. In conclusion, these results can provide some ideas and help for the development of subsequent plastic-metal hybrids and practical applications.

In recent years, organic room-temperature phosphorescence (RTP) materials have garnered significant research interest. However, the design and synthesis of novel polymeric RTP systems continue to pose substantial challenges. By leveraging cyclotriphosphazene functionalization, four novel phosphors are successfully developed. The presence of numerous heteroatoms (O, N, P) within this structure significantly enhances molecular spin-orbit coupling (SOC). Initially, the incorporation of these novel phosphors into a polyvinyl alcohol (PVA) matrix yielded only weak RTP emissions. Remarkably, thermal annealing transformed these materials into long-lived cross-linked polymer RTP films. Specifically, a representative luminescent film (THMD@PVA) exhibits enhancements in phosphorescence intensity, lifetime, afterglow brightness, and quantum yield by factors of 8, 4, 18, and 6, respectively. With superior mechanical and luminescence properties, these RTP materials are well-suited for creating flexible and reconfigurable 3D objects. Furthermore, the dual luminescence of fluorescent and phosphorescent emissions expands their applicability, including fingerprint recording, thereby broadening the application scope of organic RTP materials.

Self-healing polyurethanes are garnering attention as a smart material, and has significant application potential in aerospace, biomedical, and electronics fields. In this paper, castor oil is selected as a soft segment in place of petroleum-based polyol to enhance the mechanical properties of polyurethane while improving the mobility of molecular chains. Meanwhile, a polyurethane with good self-healing properties was successfully prepared by selecting 2,2`-Diaminodiphenyl disulfide (DTDA) containing disulfide bonds as a chain extender. As the proportion of DTDA increases, the initial thermal decomposition temperature of polyurethane decreases by 21°C. Cutting and tensile tests confirmed the high mechanical properties and self-healing characteristics of the polyurethane network. And the self-healing efficiency of the polyurethane materials was improved by prolonging the healing time and increasing the healing temperature. As the content of disulfide bonds and hard segments increased, the tensile strength of polyurethane increases progressively, the elongation at break decreased, and the R(stress) and R(strain) of each specimen tended to increase and then decrease. The healing efficiency of the specimen with a disulfide bond content of 13.45

This study investigates the surface modification of polyimide (PI) films using a 248 nm KrF excimer laser, focusing on the effects of laser parameters (such as energy density and pulse number) on the hydrophobic and hydrophilic properties of the material. By controlling the laser energy density (30-200 mJ/cm²) and pulse number (300-2100), the experiment analyzed the microstructure and wettability of the treated PI film surfaces. The results indicate that varying energy densities and pulse counts can significantly alter the surface roughness and chemical composition of PI, thereby affecting its wettability. Under the optimal conditions of 50 mJ/cm² energy density and 2100 pulses, the PI films exhibited maximum hydrophobicity, as indicated by the highest contact angle. This enhancement in hydrophobicity is attributed to the formation of a carbon-rich layered surface structure induced by the laser treatment. Additionally, when the energy density was below 100 mJ/cm², the contact angle increased with rising energy density but decreased when the energy density exceeded 100 mJ/cm², due to surface ablation that damaged the carbon-rich layer. Similarly, an increase in pulse number promoted the formation of more chemical groups, enhancing hydrophobicity, but excessive pulses could damage the surface structure. These findings demonstrate that the surface microstructure and wettability of PI films can be effectively adjusted by optimizing the laser processing parameters, which provides new ideas and theoretical support for its application in microelectronics, biomedicine, and other fields.

Polymer-metal hybrids provide solutions for energy conservation. In this study, magnesium alloy and nylon 6 were joined using hot pressing technology. Tensile shear strength of Magnesium/Nylon 6 hybrids was investigated as a function of hot pressing process parameters. In addition, failure mode and joining mechanism of interfacial bonding were revealed. It was shown that the crystallinity of nylon 6 could be improved by increasing the hot pressing pressure, thus changing the crystallinity from gamma-crystalline to the more stable alpha-crystalline. The tensile shear strength of the hybrids has been improved with the increase of the hot pressing temperature due to the better fluidity of nylon 6. At the optimal hot pressing technology (230 degrees C, 0.8 MPa, 50 s), the crystallinity of nylon 6 reached 32% and the Magnesium/Nylon 6 hybrids achieved a tensile shear strength of 13.27 MPa. Magnesium/Nylon 6 hybrids' strength is realized by a combination of interfacial mechanically interlocked structures and chemical bonding (Mg-O-C=O). It is a mixed failure mode for hybrids that includes plastic deformation of the nylon 6 and tearing of the micro-arc oxidation coating. In general, these results have important implications for the joining of metals and crystalline resins.

Plastic-metal hybrid (PMH) provides a new direction for aerospace and automotive rail transit fields to achieve lightweight. Hot pressing has broad application prospects in plastic/metal hybrids. Before the realization of TC4 (Ti-6Al-4V)/PA66(Nylon 66) hybrid by hot pressing, different porous microstructures were prepared on the surface of TC4 by controlling the micro-arc oxidation (MAO) voltage (220 V, 240 V, 260 V, 280 V). Effect of different porous ceramic structures on the hybrid interface. Research shows that the microscopic porous ceramic structure on the surface of TC4 can enhance the surface wettability and wear resistance of TC4. Promote the embedding of PA66 into the TC4 surface to achieve mechanical interlocking. Different microstructures have different effects on bonding strength and failure modes. Especially at 240 V, the interface maximum bonding strength is 11.56 Mpa, and the interface failure mode is a mixed failure caused by plastic cohesion failure and plastic pull-out. In addition, XPS detection generates new chemical bonds, such as Ti-O and -C-Ti-O, at the hybrid interface. Compound reinforcement of mechanical interlocking and chemical bonding is achieved at the interface. In conclusion, these results are crucial for further designing and optimizing plastic-metal hybrids prepared using micro-arc oxidation.

Dimethyl sulfide (DMS) is one kind of volatile sulfur compounds (VSCs) possessing disagreeable odor, with a low olfactory threshold around 20 ppb. Highly sensitive detection of DMS at room temperature (RT) is critically needed for emerging application with low power consumption, but it remains a significant challenge owing to its low reactivity. Herein, UV photoactivated titanium dioxide (TiO2) nanoparticles (NPs) have been employed for detecting DMS at RT. An eco-friendly ultrasonic crushing solution spray technique was developed to prepare TiO2 based sensors. An ultrahigh response of 30-500 ppb DMS and a low experimental limit of detection (Ra/Rg = 2.7@50 ppb) could be achieved at RT under UV light activation. This work opens a new avenue to achieve highly sensitive, energy-efficient sensors for trace VSCs detection at RT in ambient odor monitoring.

Self-sensing conductive bitumen pavement materials hold critical importance for smart transportation systems. While current research predominantly focuses on conductive asphalt concrete, the insulating nature of aggregates necessitates dependence on bitumen binders for pavement conductivity. This study addresses the fundamental challenge of constructing conductive networks within bituminous materials. A polyurethane (PU) prepolymer was synthesised via reaction between diphenylmethane diisocyanate (MDI) and polypropylene glycol (PPG), subsequently employed for bitumen modification. To enhance conductivity, carbon nanotubes (CNT) were introduced through dual pathways: direct incorporation into the bitumen matrix and integration during PU-prepolymer synthesis. Comprehensive evaluations including dynamic shear rheological (DSR) analysis, dynamic mechanical analysis (DMA), thermal conductivity, and electrical conductivity measurements were conducted. Remarkably, minimal CNT addition (2 wt.% relative to PU-prepolymer, equivalent to 0.4 wt.% in final composites) induced a four-order-of-magnitude conductivity enhancement. Mechanistic investigations via Fourier transform infrared spectroscopy (FTIR), optical microscopy, and scanning electron microscopy (SEM) revealed that CNT participation in PU-prepolymer synthesis facilitates percolated network formation. This structure concurrently improves electrical pathways and interfacial reinforcement within the bitumen matrix.

In aerospace and rail-transport engineering, lightweight metal - polymer hybrids (MPHs) are pivotal for energy-efficient structural design. Herein, a TC4 (Ti-6Al-4 V)/CFR-PA66 hybrid was fabricated via precision hot pressing. Micro-arc oxidation (MAO) was first surface modified to architect a hierarchical micro-/nano-porous ceramic coating on TC4. X-ray photoelectron spectroscopy (XPS) verified the formation of interfacial Ti - O - C bonds, yielding a bonding strength of 26.75 MPa. Failure form analysis revealed a mixed fracture mode comprising matrix plastic cohesive failure and micropore mechanical anchoring failure. Subsequent incorporation of gamma-aminopropyl triethoxysilane (KH550) introduced a hydrogen-bonded network and additional covalent Ti - O - Si bonds, elevating the bonding strength by 15.9% to 31 MPa. The optimized interface retained synergistic chemical bonding and mechanical interlocking, engendering a quasi-ductile failure dominated by coating tearing with substantial cohesive ligaments. These findings furnish a robust, scalable route for high-performance MPH design in next-generation lightweight structures.

Ultrasonic-assisted hot-pressing molding was employed to produce the plastic-metal samples to examine how the silane coupling agent affected the bonding properties of the polycarbonate/aluminum alloy hybrid. With the application of the ultrasonic field, the tensile shear strength rose. Scanning electron microscopy was utilized to examine the bonding layer of the polycarbonate/aluminum hybrid, which establishes its morphology structure. The results indicated that a mechanical interlocking structure was generated via the plastic encased in nanopores on the aluminum alloy surface. Furthermore, X-ray photoelectron spectroscopy indicated that the bonding layer was strongly connected due to the chemical bonding interactions between the Al-O-Si and (C=O)-NH groups. Specifically, the tensile shear strength of the polycarbonate/aluminum alloy hybrid reached 10.6 MPa under mechanical interlocking after the aluminum alloy was anodized with a 10% mass fraction of phosphoric acid solution. Then, after treatment with a 4% volume fraction silane coupling agent on the anodized aluminum alloy surface, the tensile shear strength of the polycarbonate/aluminum alloy hybrid reached 17.8 MPa under the combined effect of mechanical interlocking and chemical bonding, which was increased by 67.9% compared with the sample without silane coupling agent. The results indicate that the use of a silane coupling agent can effectively improve the tensile shear strength of polycarbonate/aluminum alloy hybrid.

Polymeric room-temperature phosphorescence (RTP) materials have attracted much attention due to their advantages of easy processing and excellent luminescent properties. However, it is still a challenge to obtain industrial production grade material through simple and green processing strategies. Herein, through the codoping strategy, different phosphors were embedded into nylon, a kind of polymer matrix, to obtain a series of highly efficient RTP materials without any organic solvents, for which the phosphorescence lifetime and brightness could reach 628.8 ms and 14 cd/m2, respectively. Besides, we found that the photophysical properties of these RTP materials varied greatly among different types of nylon matrix, owing to the divergence in the number of hydrogen bonding "sites". The superiority of the injection molding processing strategy enables the preparation of RTP materials to achieve desolvation, which could also be processed into any complex and desiring shape. Significantly, nylon can affect molecular chain changes due to aging and other problems, so that these RTP materials are considered as potential nondestructive testing for nylon product aging levels. This strategy also paves the way for the development of large-scale, eco-friendly, and practical application RTP materials and provides new ideas to industrialized preparation of long-lived RTP materials in the future.

The hole accumulation layer (HAL) configuration of p-type oxides (including Co3O4) in ambient air causes intrinsically low gas response and hinders their promising applications in exhaled gas analysis. Herein, Sn and Ni co-doping has been proposed to trigger the response of chemiresistive Co3O4 sensor toward acetone (biomarker of diabetes). Via incorporating 1at.% Sn and 0.5at.% Ni doping (Co2.95Sn0.03Ni0.02O4), the response to 100 ppm acetone has been boosted ~2 orders (from 1.24 to 125.6) at 70 °C, the limit of detection (LoD) has been reduced ~4 times (from 47.9 to 12.4 ppb), the optimal operation temperature has been decreased from 130 °C to ~70 °C. Various characterizations suggest that co-doping induced abundant surface asymmetric oxygen vacancy defects (Co-□-Ni, Sn-□-Ni), which facilitate the catalytic oxidation of acetone molecules at relatively low operation temperature. In addition to excellent reproducibility and long-term stability, Co2.95Sn0.03Ni0.02O4 sensor could also operate under highly humid air background and reliably detect acetone concentration in exhaled breath at 150 °C, opening the opportunity for the practical application of p-type oxide sensors for diabetes diagnosis.

A series of shape memory polyurethane (SMPU) substrates were fabricated utilizing polyether polyol (PPG) with varying molecular weights, 4,4 '-diphenylmethane diisocyanate (MDI), and4,4 '-methylene-bis-(2-chloroaniline) (MOCA) as primary raw materials. Tetrahydrofuran (THF) served as the solvent. The investigation focused on the effects of different soft segment molecular weights and additional THF content on the properties of SMPU. The study aimed to explore the impact of varying soft segment molecular weights and THF additions on the shape memory properties of polyurethane, as well as the mechanism behind THF's influence. The findings demonstrated that the introduction of THF significantly enhanced the phase separation degree and ordered hydrogen bonding of polyurethane, leading to the acquisition of shape memory properties. Compared to specimens without THF addition, when PPG had a molecular weight of 500, hydrogen bonding increased by 50 %. Furthermore, at THF addition of 9 mL, the specimen exhibited the highest shape recovery degree, with a phase separation temperature of 28.21 degree celsius, a degree of carbonyl-ordered hydrogen bonding of 49.08 %, a bending strength of 43.81 MPa, and an impact toughness of 38.19 KJ/m(2). The shape memory performance of the specimens was evaluated at various temperatures, revealing that the models both achieved 100 % shape fixation at different temperatures. Additionally, the degree and rate of retraction increase with the increase in temperature. The shape memory performance of the prepared specimens was shown to be good by the DMA shape memory cycling test.

Self-healing bitumen can significantly enhance the durability and service life of bituminous pavement, thereby reducing the need for frequent maintenance and repairs. In this study, isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), and isophorone diamine (IPDA) were utilized to design asymmetric dynamic hard segments, imparting self-healing properties to polyurethane even at room temperature. Particular emphasis was placed on hydrogen bonding, as its reversible formation serves as a primary mechanism for the self-healing characteristics of the material. During the synthesis of polyurethane (PU), two different composition ratios were employed to produce two types of PU with distinct chemical structures, molecular weights, and dynamic crosslink densities, which were characterized using NMR, FTIR, GPC, and DMA, respectively. Furthermore, these two PU types exhibited varying mechanical properties and glass transition temperatures, leading to differences in the rheological properties of the corresponding PU-modified bitumen. Dynamic frequency sweep test results indicated that bitumen modified with PU exhibiting higher molecular weight and narrower molecular weight distribution had superior rutting resistance and enhanced room-temperature self-healing capabilities. The underlying reasons for this improvement can be attributed to the hydrogen bonding present in the PU as well as the phase separation structure between the PU and bitumen.

High-entropy materials have been proposed for applications in nuclear systems recently due to their outstanding properties in extreme environments. Chemical complexity in these materials plays an important role in irradiation tolerance since it significantly affects energy dissipation and defect behaviors under particle bombardment. Indeed, better resistance to irradiation-induced amorphization was observed in the high-entropy MAX (HE-MAX) phase (Ti, M)2SnC (M = V, Nb, Zr, Hf). However, in this work, we report an opposite trend in another series of HE-MAX phases (Ti, M)2AlC (M = Nb, Ta, V, Zr). It is demonstrated that the amorphization resistance is sequentially reduced as the number of components increases from single-component Ti2AlC to (TiNbTa)2AlC and (TiNbTaVZr)2AlC. These phenomena are verified through AIMD simulations and interpreted by analyzing the underlying properties combining lattice distortion and bonding characteristics through the first-principle calculation. By developing a machine-learning (ML) model, we can directly predict lattice distortion to screen HE-MAX phases with excellent resistance to irradiation-induced amorphization. We highlight that the elemental species plays a more crucial role in the irradiation tolerance of these MAX phases than the number of constituent elements. Knowledge gained from this study will enable an improved understanding of the irradiation tolerance in HE-MAX phases and other multi-elemental ceramics.

Room-temperature phosphorescence (RTP) materials have attracted much attention due to their unique luminescence properties. However, it is very challenging to tune the afterglow color of pure amorphous polymers by using only one kind of phosphor unit so far. Here, we proposed a strategy to induce pyrene derivatives (VPY) into the main chain of the polymer by free radical copolymerization, followed by alcoholysis to form poly(vinyl alcohol) derivative materials (PVA-PVPY) with strong hydrogen bond network structures. It was surprising that the obtained intrinsic polymers containing only one kind of phosphor unit achieved multicolor long-lived RTP. The RTP performance of the obtained polymers exhibited concentration, excitation, and time dependence. The experimental and theoretical results demonstrated that these characteristics were attributed to the different aggregated states of phosphor units in polymer chains, which revealed the luminescence mechanism of the aggregated and isolated states of phosphor units to produce multicolor RTP. In addition, we explored the application of these polymers based on color-tunable RTP properties in information encryption and flexible wearables. This strategy contributes to the development of multicolored smart luminescent materials as well as flexible wearable materials.