Advanced Fiber Materials最新文献

In recent years, the collection and monitoring of human physiological signals have garnered increasing attention due to their wide-ranging applications in healthcare, human–machine interaction, sports, and other fields. However, the continuous fabrication of flexible gel fiber electrodes with high mechanical performance, high conductivity, and durability for extreme environments using a simple, efficient, and universal strategy remains challenging for physiological signal acquisition. Here, we have employed a strategy of solvent replacement and multi-level hydrogen bond enhancement to construct eutectogel fibers with continuous solid–liquid structure, achieving continuous production of fibers with high strength, high conductivity, and low-temperature resistance. In the fiber, PVA serves as the solid-state elastic phase, DES as the liquid ionic conductive phase, and CNF as the reinforcement phase. The resulting eutectogel fibers exhibit excellent tensile strength (37.3 MPa), good elongation (> 700%), high electrical conductivity (0.543 S/m), and resistance to extreme dry and −60 °C low-temperature environments. Furthermore, these eutectogel fibers demonstrate high sensitivity for monitoring joint movements and effectively detecting in vitro and in vivo signals, show casing their potential for wearable strain sensors and monitoring physiological signals.

Clinical diagnosis and early intervention employ pedobarometry, which analyzes gait, posture, and foot health. Athletes utilize smart insoles to track step count, distance, and other parameters to improve performance. Current sensor platforms are bulky and limited to indoor or clinical environments, despite the trend of developing specialized insoles for recuperation and therapy. Hence, we presented a fully flexible, typically portable, and multi-functional insole monitoring technology powered by Archimedean algorithmic spiral TENG-based power system strictly produced from biopolymers such as bacterial cellulose, conjugate-blend of polydimethylsiloxane (PDMS), poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), and more. Along with exceptional mechanical and electrical performance [current density (J_SC) ≈ 40–50 μA/cm² and power density (P_D) ≈ 500–600 μW/cm²], the smart insole system exhibited good sensor-human foot interfacial analysis results, proving to be capable of biomechanical analysis of gait, posture, and many other podiatry-related conditions, albeit being soft, portable, and having compatibility potential for IoT integration.

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Passive cooling holds tremendous potential in improving thermal comfort because of its zero energy consumption and cost-effectiveness. However, currently reported radiative cooling materials primarily focus on hydrophobic polymer films, inevitably leading to sweat accumulation and limited cooling efficiency in hot-humid environments. Herein, an advanced Janus membrane with excellent temperature–moisture management capabilities is developed, which combines radiative cooling and evaporative heat dissipation. Modification with Calcium sulfite (CaSO₃) nanoparticles not only enhances the optical properties (state-of-the-art solar reflectance of 96.6%, infrared emittance of 96.1%) but also improves the wettability of the polylactic acid fiber membrane. Especially 15% emittance improvement is achieved due to the strong infrared radiation ability of CaSO₃. The membranes with opposite wettability realize the directional sweat transport (high one-way transport index of 945%). Excellent radiative cooling capability is demonstrated with sub-ambient cooling of 5.8 °C in the dry state. The Janus membranes covering sweaty skin exhibit a 46% shorter drying time and a 2 °C lower average evaporation temperature compared to cotton fabric, indicating highly efficient thermal and moisture management. This work provides an efficient route to achieving smart textiles that enable the human body to adapt to complex environmental conditions.

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Hydrogel fibers have gained considerable attention, but their large-scale production and industrial application are currently constrained. The key lies in precise diameter control and industrial manufacturing with a straightforward, energy-saving, and efficient strategy. Herein, we introduce a hydrodynamic drafting spinning platform inspired by water vortices. It employs the rotation of a nonsolvent to generate vortices and further facilitate the efficient drafting of hydrogel fibers. Through supporting equipment, we have achieved impressive results, including scalable production capabilities (1 h, single channel output of 2 × 10³ m of fibers) and extensive adaptability. Subsequently, by simply regulating the velocity difference between fiber extrusion and fluid vortex, hydrogel fibers can be drafted to any diameter from about 1 mm to 5 × 10^–2 mm (for chitosan system). Notably, this platform endows hydrogel fibers to carry functional hydrophilic or hydrophobic drugs. Equally significant, these delicate hydrogel fibers seamlessly integrate with subsequent manufacturing technologies. This allows the production of various end products, such as fiber bundles, yarns, fabrics, and nonwovens. Furthermore, the immense potential in biomedical applications has been demonstrated after obtaining hydrogel fiber-based nonwoven as wound dressings. In summary, the hydrodynamic drafting spinning platform offers an effective solution for the large-scale production of diameter-controllable, multifunctional hydrogel fibers.

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Aerogel fiber has broad applications in thermal insulation, pollution adsorption, biomedicine, energy storage, and aerospace. However, the large-scale and continuous production of aerogel fibers remains a significant challenge. Wet spinning technology transforms the static sol–gel process into rapid dynamic gel fiber molding, and is the preferred spinning method for continuous molding and large-scale production of aerogel fibers. This review provides a systematic overview of the production process of wet-spun aerogel fibers and the obstacles it encounters in the forming and drying stages. It also discusses the progress of different spinning strategies in optimizing the structure and properties of aerogel fibers. Recent advances in the properties of aerogel fibers, such as thermal insulation, adsorption, and optical and electromagnetic shielding, which are affected by the structural characteristics of aerogel fibers, are presented. Finally, this review provides a brief conclusion and discusses the technical challenges and future directions for wet-spun aerogel fibers. This review is expected to offer fresh perspectives and innovative strategies for the continuous production of aerogel fibers, the development of high-performance and multifunctional aerogel fibers, and their diverse applications.

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Stretchable conductive fibers composed of conductive materials and elastic substrates have advantages such as braiding ability, electrical conductivity, and high resilience, making them ideal materials for fibrous wearable strain sensors. However, the weak interface between the conductive materials and elastic substrates restricts fibers flexibility under strain, leading to challenges in achieving both linearity and sensitivity of the as-prepared fibrous strain sensor. Herein, cryo-spun drying strategy is proposed to fabricate the thermoplastic polyurethane (TPU) fiber with anisotropic conductive networks (ACN@TPU fiber). Benefiting from the excellent mechanical properties of TPU, and the excellent interface among TPU, silver nanoparticles (AgNPs) and polyvinyl alcohol (PVA), the prepared ACN@TPU fiber exhibits an outstanding mechanical performance. The anisotropic conductive networks enable the ACN@TPU fiber to achieve high sensitivity (gauge factor, (GF) = 4.68) and excellent linearity within a wide working range (100% strain). Furthermore, mathematical model based on AgNPs is established and the resistance calculation equation is derived, with a highly matched fitting and experimental results ((R^{2}) = 0.998). As a conceptual demonstration, the ACN@TPU fiber sensor is worn on a mannequin to accurately and instantly detect movements. Therefore, the successful construction of ACN@TPU fiber with anisotropic conductive networks through the cryo-spun drying strategy provides a feasible approach for the design and preparation of fibrous strain sensing materials with high linearity and high sensitivity.

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Delayed healing of diabetic wounds poses a major challenge to human health due to severe vascular dysfunction, sustained inflammation, and vulnerability to microbial infection. Herein, we constructed multidimensionally nano-topologized electrospun polycaprolactone (PCL) fibrous membranes with shish-kebab nanoarrays on each fiber through self-induced crystallization, on which the CuO₂–MgO₂ bimetallic peroxide nanodots (BPNs) were anchored by polydopamine (PDA) as the bridging layer. When activated by the acidic microenvironment (typically infected diabetic wound), BPNs on fibers reacted immediately to release Cu²⁺ and Mg²⁺ ions together with hydrogen peroxide (H₂O₂) molecules, which were then transferred into ·OH radicals through Fenton-type reactions catalyzed by Cu²⁺ for instant bacteria elimination. At the same time, the released Cu²⁺ and Mg²⁺ ions were retained to improve the angiogenesis and suppress the inflammation infiltration, thus remodeling the wound microenvironment. Meanwhile, the one-dimensional (1D)-constructed nano shish-kebabs and PDA coating on fibers provided additional topological activation for cell adhesion and directed migration along the aligned fiber orientation. Through the meticulous design, the resultant membranes markedly accelerated the infected wound healing in the diabetic rat model. This study pioneers a unique design to develop a nanocomposite fibrous membrane that combines multidimensional topologies with chemodynamic therapy (CDT), for efficiently combating infected diabetic wounds.

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Fiber supercapacitors (FSs) based on transition metal oxides (TMOs) have garnered considerable attention as energy storage solutions for wearable electronics owing to their exceptional characteristics, including superior comfortability and low weights. These materials are known to exhibit high energy densities, high specific capacitances, and fast redox reactions. However, current fabrication methods for these structures primarily rely on chemical deposition, often resulting in undesirable material structures and necessitating the use of additives, which can degrade the electrochemical performance of such structures. Herein, physically deposited TMO nanoribbon yarns generated via delamination engineering of nanopatterned TMO/metal/TMO trilayer arrays are proposed as potential high-performance FSs. To prepare these arrays, the target materials were initially deposited using a nanoline mold, and subsequently, the nanoribbon was suspended through selective plasma etching to obtain the desired twisted yarn structures. Because of the direct formation of TMOs on Ni electrodes, a high energy/power density and excellent electrochemical stability were achieved in asymmetric FS devices incorporating CoNixOy nanoribbon yarns and graphene fibers. Furthermore, a triboelectric nanogenerator, pressure sensor, and flexible light-emitting diode were synergistically combined with the FS. The integration of wearable electronic components, encompassing energy harvesting, energy storage, and powering sensing/display devices, is promising for the development of future smart textiles.

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Development of novel electrode materials with the integration of structural and compositional merits can essentially improve the electrosorption performance. Herein, we demonstrate a new strategy, named as carbothermal diffusion reaction synthesis (CDRS), to fabricate binder-free CrN/carbon nanofiber electrodes for efficient electrosorption of fluoride ions from water. The CDRS strategy involves electrospinning MIL-101(Cr) particles with polyacrylonitrile (PAN) to form one-dimensional nanofiber, followed by spatial-confined pyrolysis process in which the nitridation reaction occurred between nitrogen element from PAN and chromium element from MIL-101(Cr), resulting macroscopic, free-standing electrodes with well dispersed ultrafine CrN nanoparticles on porous nitrogen enriched carbon matrix. As expected, the F⁻ adsorption capacity reached 47.67 mg g⁻¹ and there was no decrease in F⁻ removal after 70 adsorption regenerations in 50 mg L⁻¹ F⁻ solution at 1.2 V. The adsorption mechanism of F⁻ was explored by X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT). The enhanced F⁻ adsorption capacity was achieved by the reversible Cr⁴⁺/Cr³⁺ redox pair provided by CrN and the electrical double layer capacitance produced by carbon skeleton. This study provides guidance on synergistic modulation of shaping and composition optimization of novel functional materials for electrosorption, catalysis, and supercapacitor applications.

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In the last decade, numerous physical modification methods have been introduced to enhance triboelectric nanogenerator (TENG) performance although they generally require complex and multiple fabrication processes. This study proposes a facile fabrication process for Poly(vinylidene fluoride) (PVDF) nanofiber (NF) mats incorporating additive and nonadditive physical modifications. Patterned PVDF NF mats are prepared by electrospinning using a metal mesh as the NF collector. As a negative triboelectric material, the TENG with the patterned PVDF NF mat exhibits superior performance owing to the engineered morphology of the contact layer. PVDF is crucial in TENGs owing to its superior ferroelectric properties and surface charge density when combined with specific electroceramics. Hence, the synergy of the physical modification methods is achieved by incorporating BaTiO₃ (BTO) nanoparticles (NPs) into the PVDF. By functionalizing BTO NPs with polydopamine, the TENG performance is further improved owing to the enhanced dispersion of NPs and improved crystallinity of the PVDF chains. Utilizing large NPs produces a nanopatterning effect on the NF surface, thereby resulting in the hierarchical structure of the NF mats. The source of the voltage signals from the TENG is analyzed using fast Fourier transform.

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