In response to growing demands for environmentally friendly flame-retardant materials, this study develops a novel waterborne polyurethane (WPU) by incorporating the reactive phosphaphenanthrene-based compound DOPO-HQ into the polymer backbone. The modified WPUs, denoted as P-WPUx, exhibit significantly enhanced flame retardancy without appreciably compromising mechanical performance. With only 3 wt % DOPO-HQ loading, P-WPU3 achieves an LOI of 35.35%, satisfies the UL-94 V-0 requirement, and retains mechanical robustness with 33.0 MPa tensile strength and 737.8% elongation. Comprehensive analyses confirm that DOPO-HQ operates via a dual-phase mechanism: scavenging free radicals within the gas phase while simultaneously facilitating carbonaceous layer development in the condensed phase. These findings underscore the potential of molecularly integrated phosphorus-containing modifiers in the design of high-performance, sustainable flame-retardant WPU materials.

The BiO bond is widely regarded as the key motif for CO2 electroreduction towards formate, but the role of specific BiO coordination remains unclear. Herein, we study the electrocatalytic behavior of a Bi4Ti3O12 perovskite containing BiO6 and BiO7 structures. Under 24-h CO2 reduction reaction (CO2RR), Bi4Ti3O12 reconstructs into Bi2O2CO3 while retaining BiO7 and maintaining high formate Faradaic efficiency (FE). In contrast, electrochemical measurements and in-situ attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) confirm Bi2O3 lacking BiO7 favors hydrogen evolution reaction (HER). Density functional theory (DFT) calculations indicate BiO7 lowers the energy barrier for *OCHO generation, identifying it as the key active site. Using a solid-state electrolyte (SSE) reactor, pure formic acid (0.19 M) is continuously produced with ∼70% FE over 48 h. This work indicates that the coordination environment of BiO motif displays an essential role in selectivity, and that the BiO7 motif might be the critical active site for formate production.

Existing triboelectric nanogenerators (TENGs) for wearable sweat sensors are plagued by low power density, which restricts their practical application. This study focuses on boosting TENGs output power via a fluorinated bi-layer electronic textile (e-textile) fabricated by electrospinning rotary collection, enabling self-powered dual functionality: real-time electrochemical sweat sensing and human motion detection. The key design includes a PCLU-HFDD negative triboelectric layer (molecularly incorporated with hexadecafluorodecanediol to enhance electron affinity) and a poly(lactic-co-glycolic acid) (PLGA) positive layer. Rotary collection creates vein-like nanostructures on PCLU-HFDD yarns (6.2 mu m roughness, 114.8 degrees water contact angle), increasing contact area. The PCLU-HFDD TENG achieves a high power density of 0.66 W m- 2, an open-circuit voltage (Voc) of 117.08 V, and excellent stability over 35,000 contact-separation cycles. Critically, integrated with both sweat-sensing and motion-detection capabilities, the e-textile enables 180-min continuous glucose monitoring (under sedentary conditions) and recognition of human motions. This work confirms that the power enhancement not only overcomes the bottleneck of TENGs for wearable sensors but also facilitates dual-modal health monitoring, advancing the development of practical wearable bioelectronics.

Silicon dioxide (SiO2) has emerged as a cornerstone in the design of nano-luminescent materials owing to its exceptional chemical stability, structural tunability, and biocompatibility. This review systematically highlights the pivotal functions of SiO2 in three domains: stability enhancement, structural regulation, and function expansion. As a physical barrier, silica effectively prevents water and oxygen-induced degradation, thereby markedly improving the chemical and photostability of sensitive emitters. As a structural matrix, its mesoporous frameworks and surface chemistry enable precise loading, spatial confinement, and integration of luminescent units, while the control of pore size, defect states, and interfacial interactions allows tailoring of optical properties and energy-transfer pathways. Furthermore, advanced architectures such as core-shell, Janus, and chiral structures extend the functional boundaries of SiO2-based systems, unlocking opportunities in bioimaging, anti-counterfeiting, and smart sensing. Built on these functions, the review introduces six representative nano-luminescent materials based on silica hybrid systems (including hybrids with carbon quantum dots, inorganic quantum dots, upconversion nanoparticles, perovskites, metal nanoparticles, and organic fluorophores), and demonstrates how silica imparts stability, structural regulation, and multifunctionality for nano-luminescent materials. Finally, current challenges, such as scalable synthesis, stability under extreme environments, and potential biosafety risks, are critically discussed. We believe that a possible future direction is an integrated development strategy of "intelligent design-precise regulation-green optimization", offering theoretical and practical guidance for advancing nano-luminescent materials toward real-world applications in biomedicine, optoelectronics, and environmental monitoring.

When thermally conductive nanomaterials were assembled into composites with polymers, the serious phonon scattering at a large number of interfaces between individual nano building blocks would dramatically lower the thermal conductivities (2) of the composites. Architecting chemical bonds between these nano-units is an effective way to improve the 2 of the composite due to the bridging of lattice vibrations, namely phonon bridges. Herein, we utilized the fluidity of liquid metal gallium (Ga) and its coordination with nitrogen of hexagonal boron nitride (h-BN) to realize the intercalation exfoliation of h-BN, and the Ga could also be chemically modified on the exfoliated boron nitride nanosheets (BNNSs). The BNNS-Ga assembled films with polymers showed superior 2 due to the strong phonon bridging and Ga-induced densification and horizontal orientation of BNNSs. A high in-plane 2 of 28.99 W center dot m-1 center dot K-1 was obtained for the BNNS-Ga/polymer composites.

Flexible resistive strain sensors based on silver nanowires (AgNWs) demonstrate significant potential for wearable electronics and human motion monitoring; however, they face substantial challenges due to severe modulus mismatch and limited cyclic stability under large-amplitude strain. In this context, a sandwich-structured strain sensor was developed based on supramolecular polyurethane functionalized with dynamic polyrotaxane (PR) sliding rings, where the freely mobile α-cyclodextrin units dissipate interfacial stress and stabilize the AgNWs conductive network under repeated stretching. The optimized sensor achieves an ultra-wide operational strain up to 700% and a high gauge factor of 141. Importantly, it maintains a stable resistance response over 20,000 loading-unloading cycles at 200% strain, surpassing all previously reported pristine AgNWs-based counterparts. Additionally, it exhibits 98% mechanical self-healing efficiency at 50 °C within 30 min, along with excellent breathability and alkaline degradability. This research presents a promising strategy for the development of high-performance, sustainable wearable sensing devices.

Triboelectric nanogenerators (TENGs) hold significant potential for powering flexible wearable electronics; however, their widespread adoption is limited by mechanical wear, harsh environment (e.g., to humidity and contaminants), and the need for external intervention to trigger self-powered heating self-healing. In this work, we presented a breathable TENG fabricated from electrospun nanofiber mats of a novel PDMS-TPU-HFDD copolymer, which combines self-powered heating self-healing, self-cleaning, and exceptional environmental stability in a single-material system. The copolymer was synthesized through chain extension of prepolymers utilizing polycaprolactone diol (PCL diol), polydimethylsiloxane diol (PDMS diol), and isophorone diisocyanate (IPDI) with fluorinated chain extender hexadecafluorodecanediol (HFDD), resulting in a melting transition as low as 38.10 °C. The TENG device utilized the copolymer electrospun nanofiber mat as the triboelectric layer and the carbon cloth as the flexible electrode. The integrated device self-powered heating self-healed within 3 min via the Joule heating effect of carbon cloth (2.8 V, 43.3 °C) and maintains 98% of its performance over 4500 abrasion cycles. Moreover, the device demonstrated both high breathability and excellent stability in high-humidity environments. Its water vapor transmission rate was comparable to that of an open container, retaining 78% of its electrical output even at 60% relative humidity. The device demonstrated a maximum open-circuit voltage of 150 V, short-circuit current of 14 μA, and a power density of 0.275 W/m2─surpassing the performance of conventional PCL-TPU-BDO-based devices by two to three times. This multifunctional TENG represents a substantial step toward durable, self-sustaining, and practical power sources for next-generation wearable electronics.

Owing to the unique structural characteristics and heteroatom doping as electrode materials for supercapacitor application, nitrogen-doped hollow porous carbon spheres (N-HPCS) have been extensively studied. However, the synthesis of N-HPCS with high nitrogen contents above 15% (mass fraction) is still a great challenge. Herein, an ethylenediamine-assisted co-assembly strategy is used to control the self-assembly between the 2,6-diaminopyridine-glyoxal Schiff base polymer precursor and the silica template, resulting in high N-content N-HPCS. The N-HPCS renders quantitatively controllable shell thickness (7-40 nm), controllable diameter of cavity (270-620 nm), high and adjustable N content (up to 15.1%, mass fraction), as well as a high ratio of beneficial N species (44.5% pyridine N and 36.7% pyridone/pyrrole N). N-HPCS exhibits excellent properties for supercapacitors with a ratio capacitance of 335 F/g at 0.2 A/g, and almost no attenuation of specific capacitance after 3000 cycles at a current density of 5 A/g, showing excellent cycle stability. The as-synthesized N-HPCS with high surface area, hollow structure and high nitrogen content exhibits broad application prospects as an advanced energy storage material.

In the co-intercalation type of magnesium-lithium hybrid batteries (MLHBs) system, the insertion of Li+ enhances the electrochemical activity of the Chevrel phase cathode materials for Mg2+. However, the mechanism behind the synergistic diffusion mechanism of mixed multivalent ions still needs further research regarding other non Chevrel phase cathode materials. The present study is the first to reveal the diffusion mechanism of Li+/ Mg2+ in oxygen vacancy anatase TiO2 (TiO2-x). Pristine TiO2 exhibits strong electrochemical inertness to Li+ and Mg2+, oxygen vacancies induce the preferential insertion of Li+ to form LiyTiO2-x structure. This in turn activates the electrochemical activity of TiO2 to Mg2+. Experimental results illustrate that the oxygen vacancies not only improve the intrinsic electronic conductivity of TiO2, but also weaken the electrostatic shielding effect between Mg2+ and lattice oxygen during the diffusion process. LiyTiO2-x compounds formed by Li+ preferentially intercalation can further reduce the diffusion energy barrier of Mg2+. The other hand, reduced graphene oxide (rGO) is used as the substrate to further improve the structural stability of TiO2-x. The prepared TiO2-x/rGO composite (denoted as NTR) as MLHBs cathode delivers outstanding lithium-magnesium co-storage performance (253.77 mAh g-1 at 0.1 A g-1; the capacity is 127.3 mAh g-1 at 0.5 A g-1 after 750 cycles). The present research emphasizes that the optimization of the charge environment during the diffusion of Mg2+ is an important factor in achieving the rapid diffusion of Mg2+. This modification strategy opens a new way for other transition metal oxides (TMOs) to be used as co-intercalated MLHBs cathode materials.

The development of segregated structures in conductive polymer composites (s-CPCs) represents a promising approach for attaining superior electrical properties at reduced filler concentrations, yet enhancing the mechanical properties of s-CPCs while maintaining their high conductivity remains a crucial challenge due to inadequate interfacial bonding and inherent microstructural imperfections. By in situ polymerization of polyaniline (PANI) fibers on the surface of highly conductive edge-oxidized graphene (EOG) nanosheets, an interface-reinforced segregated structure was constructed in polyethylene (HDPE)-based s-CPCs with good mechanical properties and high electrical conductivity through a simple mechanical mixing and compression molding method. The PANI interlayer effectively suppressed EOG aggregation and bridged insulating gaps within the segregated conductive network, significantly reducing the surface resistivity to 6.56 x 103 Omega. Simultaneously, the surface-grafted PANI fibers facilitated HDPE molecular chain diffusion across interfaces, compensating for interfacial microdefects and enabling extraordinary ductility improvement, as evidenced by the elongation at break increased from 58% to 313%. This work provided a strategy for fabricating polyolefin-based s-CPCs with good mechanical properties and high electrical conductivity for applications.

Intumescent fire-resistant coatings (IFRC) are widely used for steel structures. The fire protection performance of the coating is closely related to its expansion and the strength of the char residue. However, these properties are often in contradiction. Recent studies suggest that resin properties play a crucial role in expansion and charring processes. Here, copolymer resins are synthesized using styrene (St), 2-ethylhexyl acrylate (2Eha), and isobutyl methacrylate (iBma), via suspension polymerization, to regulate the expansion behavior and char strength of the IFRC. Using experimental characterization combined with density functional theory (DFT), multilevel structures of the terpolymer are analyzed, consisting of plasticizing fillers formed by polymerization-induced phase separation (PIPS) and a crosslinked layer of hydrogen bonding. The IFRCs made of the copolymer resins are then evaluated for expansion and char strength, and the positive effects of the multilevel structures on performance are discussed. The results show that 2Eha significantly enhances the expansion performance, whereas iBma and St improve the char strength. The optimized IFRC, prepared from the terpolymer resin (10 wt% iBma, 20 wt% 2Eha, and 70 wt% St), extends the time to reach the steel failure temperature of 535 degrees C from 1276 s (uncoated) to 3236 s, a 253 % increase in the safe period. Additionally, the IFRC exhibits good flame retardancy and low smoke emission, with a peak heat release rate (PHRR) of 30.15 kW/m2, fire performance index (FPI) of 4.48 m2s/kW, fire growth index (FGI) of 0.195 kW/m2/s, and smoke production rate (SPR) of 0.01649 m2/s.

Multifunctional Polyimide (PI) with low dielectric and high thermal conductivity are widely utilized in high-signal-frequency and high-integration electronic devices, yet they are vulnerable to damage within complex operating environments. The development of such high-performance multifunctional composites with recyclable and repairable capability has represented significant challenges. Herein, novelty supramolecular PI nano-composites comprising Schiff base bonds and hydron bonding interactions via amino-terminated polyimide, functionalized boron nitride nanosheets and aldehyde-containing crosslinking agents maintain the inherent high thermal stability and tensile strength of conventional PI and demonstrate fully closed-loop pH-adjusted liquid-level and high-purity powder-level recyclability, as well as superior healing ability after various mechanical or electrical damage. The resultant PI nanocomposite exhibits notable comprehensive performance, with high recycled in-plane and through-plane thermal conductivity of 8.69 and 5.44 W m-1 K-1, low recycled dielectric constant of 2.98 at 1 MHz and excellent healed dielectric breakdown strength of 378.9 kV mm-1, as well as high recovery rates. Furthermore, the repairable triboelectric nanogenerator based on the PI nanocomposite exhibits excellent shape tailorability and nearly-consistent output electrical performance. The concepts presented in this paper offer practical solutions for sustainable high-performance electronic materials and shed light on the integrated structural design of green nanocomposites.

Polyamide 66 (PA66)-based composites with ultra-high conductivity and low percolation threshold as well as enhanced toughness were fabricated via facile melt blending and supercritical CO2 foaming. The tensile tests confirmed the optimal polypropylene (PP) content of 20 wt% in "sea-island" structured PA66/PP blends to guarantee the structural integrity of the PA66 phase. The conductivity measurements manifested that adding PP lowered the percolation threshold of the composites to 4.1 vol% and simultaneously increased the maximum conductivity to 62.1 S/cm, demonstrating superior conductivity performance related to most previously reported PA-based CPCs. The significant enhancement in conductivity could be mainly ascribed to the selective location of CNT in the composites and the changes in crystallization behavior induced by PP introduction. Additionally, PP incorporation improved the tensile toughness of the PA66/PP/CNT due to the interfacial compatibility of maleic anhydride-grafted PP. Thereafter, the microcellular architecture was successfully integrated into PA66/PP/CNT composites through supercritical CO2-assisted foaming technique, enabling simultaneous attainment of weight reduction and toughness enhancement as well as remarkably reduced percolation threshold and elevated the conductivity of the composites at low CNT loading. This work offers an in-depth insight into the architectural design for high-performance CPCs with light weight, high conductivity and good toughness.

Real-time, low-power, and selective detection of ammonia (NH3) is of critical importance in semiconductor manufacturing, environmental monitoring, and occupational safety. However, current sensing technologies often fall short in achieving a balance between sensitivity, stability, device integration, and user accessibility. In this work, we introduce a structurally asymmetric porous organic polymer membrane, synthesized via a liquid-liquid interfacial acylhydrazone condensation reaction, that enables rapid (similar to 1 s), reversible, and visually perceptible colorimetric sensing of NH3. The membrane exhibits dynamic keto-enol tautomerism and a well-defined anisotropic morphology-featuring a dense organic-phase side and a highly porous, fibrous aqueous-phase side-that collectively enhance molecular diffusion and optical responsiveness. Upon exposure to NH3, the disruption of intramolecular hydrogen bonding within the membrane backbone induces a pronounced absorption red-shift and a visible color transition from pale yellow to orange. Building on these molecular-level interactions, we engineer a laminated optical sensor that leverages UV-vis absorption changes for device-level signal transduction, achieving a quantification limit as low as 1 ppm. Additionally, we implement a smartphone-assisted RGB extraction method to enable semi-quantitative and user-friendly data analysis, highlighting the potential of the membrane for intelligent, field-deployable sensing. This work establishes a new paradigm in porous organic polymer-based gas sensors by uniting dynamic covalent chemistry, interfacial nanostructuring, and accessible device engineering to meet the demands of next-generation ammonia monitoring.

MgO-CaO refractories have attracted much attention in the field of clean steel due to the ability of their internal CaO to adsorb elements such as S and P in molten steel. However, there are still some problems such as difficult sintering and insufficient corrosion resistance existing in this system. Different contents of Y2O3 were introduced into MgO-CaO system to prepare MgO-CaO-Y2O3 ternary refractories via traditional and induction sintering methods. The influence of microstructural regulation on the slag-resistant properties of the refractories was investigated. The results show that the introduction of Y2O3 in the MgO-CaO refractories prepared via the two sintering methods leads to the grain boundary reconstruction effect. Under the condition of traditional sintering, when a smaller amount of Y2O3 is introduced into the MgO-CaO refractories, Y2O3 is able to activate the lattice, promote sintering, and improve the densification of the refractories. However, when more Y2O3 is introduced, the excess Y2O3 hinders the sintering densification process. Combined with lamellar intergranular phase generated in the refractories, Y2O3-based solid solution can react with the slag, increase the slag viscosity and inhibit the penetration of the slag into the refractories. Under the condition of induction sintering, the solid solution of yttrium ions in CaO is increased by using the coupling of electromagnetic and thermal fields. Compared with the MgO-CaO refractories with high Y2O3 content prepared by traditional sintering, the induction sintered refractories have higher densification, which further increases the corrosion resistance. The results provide a new path for developing long-life MgO-CaO based refractories.

The generation of economically valuable chemicals through electrocatalytic CO2 reduction reaction (CO2RR) is a highly attractive strategy for achieving the carbon cycle. Bismuth (Bi) is a prospective element due to the high selectivity for formate. Researches demonstrate the Bi-O bonds have a significant effect on the key *OCHO intermediate. Herein, we report a F-doped catalyst that displays remarkable performance in generating formate in pH-universal electrolytes. Specifically, the as-prepared F-Bi/BOC@GO achieves formate Faradaic efficiencies (FEformate) around 95% in a wide range of pH from 1 to 13.6. Furthermore, at an industrial level, current density of 200 mA cm-2 , the F-Bi/BOC@GO catalyst shows a much more stable FEformate than the catalyst without introducing F. In situ Raman reveals that the doped F can greatly improve the stability of Bi-O bonds during the electroreduction process. DFT calculations further demonstrate that fluorine doping raises the energy barrier for oxygen desorption from Bi-O motifs, thus enhancing the stability of active sites. Combined with X-ray photoelectron spectroscopy (XPS), the doped F acts as an electron trapping, which may direct electrons towards Bi-Bi bonds, thus protecting the key Bi-O motif. This work reveals the critical role of fluorine in stabilizing Bi-O active centers across a wide pH range, maintaining high formate Faradaic efficiency for a longer time than the catalyst without fluorine introduction. (c) 2025 Published by Elsevier B.V. and Science Press on behalf of Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences.

Photosensitive polyimide (PSPI) integrates photoresist and dielectric interlayer functions for efficient electronic fabrication, yet suffers from limited resolution and elevated dielectric constants, particularly in advanced integrated circuits (ICs). In this study, through integrated molecular design and component screening, a novel PSPI system incorporating intrinsically low‐polarization photosensitive groups and efficient chemical amplification is found to exhibit low dielectric properties (ɛ = 2.241, tanδ = 0.0137 at 10 GHz), submicron‐level resolution (≈880 nm), low thermal imidization temperature (180°C), and low coefficient of thermal expansion (26 ppm K −1 ). This PSPI system is fully compatible with modern IC manufacturing processes, and its superior photosensitivity (33.15 mJ cm⁻ 2 ) and high contrast (3.03) further support laser direct writing. Moreover, as an encapsulation material and dielectric interlayer in flexible multilayer circuits, the PSPI system demonstrates robust bending durability and enhances high‐frequency signal integrity with minimal parasitic capacitance. Coupled with nanodiamond nitrogen‐vacancy centers, low‐dielectric PSPI‐based circuit boards significantly improve quantum sensing and imaging, providing higher signal fidelity and enabling precise nanotesla‐scale measurements in weak magnetic fields. This breakthrough advances the resolution of PSPI to an unprecedented nanometer scale while maintaining exceptional dielectric performance, establishing it as a pivotal enabler for next‐generation flexible integrated systems requiring precise signal transmission.

The polycarbonate (bisphenol A)/acrylonitrile-butadiene-styrene (PC/ABS) features excellent mechanical properties, but its high flammability poses a potential safety hazard in practical applications. Although the incorporation of halogen-free additives enhances flame retardancy, it often leads to substantial smoke emission and compromises the mechanical properties of PC/ABS alloy. Therefore, simultaneous enhancement of both flame retardancy with low smoke and mechanical properties holds significant practical value for material development. Herein, a low-smoke PC/ABS composite with balanced flame retardancy and mechanical properties was achieved through an efficient ternary flame retardant system containing bisphenol A bis(diphenyl phosphate) (BDP), potassium-4-(phenylsulfonyl) benzenesulfonate (KSS), and 3-glycidyloxypropyltrimethoxysilane-modified boehmite (m-BM). PC/ABS/ BDP6/KSS2/m-BM2 can achieve the same flame retardant level (V-0) as PC/ABS/BDP14, and the limiting oxygen index is increased to 26.8%. Meanwhile, the tensile strength and impact strength are increased by 16.1% and 81.4% respectively. The ternary system can significantly inhibit the release of smoke and heat, under the same flame retardant load (10% (mass)), the total heat release and total smoke production of PC/ABS loaded with ternary flame-retardant system decreased by 18.1% and 21.9% respectively compared to only BDP loaded. This ternary flame-retardant system provides a practical solution for developing high-performance, low-smoke flame-retardant PC/ABS composites. (c) 2025 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Sarin is an extremely toxic and fast-acting chemical warfare nerve agent that poses a serious threat to human health, necessitating the development of appropriate sensing technologies. Dimethyl methylphosphonate (DMMP), which has a chemical structure similar to that of sarin but is non-toxic, is often used as a simulation agent in related research. Among promising gas-sensing materials, CuFe2O4 exhibits suitable thermal stability. It is easily produced and has low toxicity. Its performance can be enhanced using heterogeneous ion doping to increase the number of surface defects and content of adsorbed oxygen. Therefore, a solvothermal method was adopted in this study to prepare CuFe2O4 hollow microspheres that were subsequently doped with different ratios of Sn4+ or Sn2+. Detailed characterizations of the obtained materials were conducted, and the corresponding CuFe2O4-based gas sensors were fabricated. Their gas-sensing performance against DMMP was studied to analyze and discuss the gas-sensing and sensitization mechanisms associated with Sn4+ and Sn2+ doping. The CuFe2O4-based sensor doped with 2 mol% Sn2+ exhibited excellent gas-sensing performance in response to a 1 ppm concentration of DMMP, with response and recovery times of 12 and 63 s, respectively. Notably, its response to 1 ppm DMMP (16.27) was 3.3-fold higher than that to 1 ppm 2-CEES (4.98). The doped CuFe2O4 sensor exhibited superior response-recovery characteristics and enhanced moisture resistance compared to the undoped sensor.