Advanced Fiber Materials最新文献

The rapid growth of wearable technology has significantly enhanced the capabilities of wearable sensors, transitioning from simple attachments of rigid electronics to the more comfortable and adaptable integration with soft substrates. Among these, flexible piezoresistive pressure sensors are particularly notable for their straightforward and reliable signal readout. Fiber, yarn, and textile-based sensors, which allow for multiscale material and structural engineering, present ideal solutions for achieving sensors with excellent wearability, sensitivity, and scalability potential. Innovations in materials and the advancement of artificial intelligence (AI) have further enhanced sensor performance, adding multifunctional capabilities and broadening their applications. This review systematically examines fiber, yarn, and textile-based piezoresistive pressure sensors, covering fundamental mechanisms, key performance metrics, conductive and substrate materials, structural designs, fabrication techniques, multifunctional integrations, and advanced applications in healthcare, fitness, and human–machine interaction, augmented by machine learning (ML). Finally, the review discusses sensor design and technical considerations, material–structure–property engineering, scalable production, performance evaluation, and offers recommendations and prospects for future sensor research and development. This comprehensive overview aims to provide a deeper understanding of current innovations and challenges, facilitating the advancement of flexible and intelligent wearable sensing technologies.

The rapid advancement of personalized healthcare brings forth a myriad of self-powered integrated sweat fabric systems. However, challenges such as alkaline by-products, low open-circuit voltage and output power have made them unsuitable for the continuously powering biosensors. Here, we have designed a sweat-activated polyaniline/single-wall carbon nanotube||Zinc (PANI/SWCNTs||Zn) battery fabric featuring multiple redox states. This innovative battery achieves a high open-circuit voltage of 1.2 V within 1.0 s and boasts an impressive power density of 2.5 mW cm⁻² due to the rapid solid–liquid two-phase electronic/ionic transfer interface. In-depth characterization reveals that the discharge mechanism involves the reduction of emeraldine salt to leucoemeraldine without oxygen reduction. By integrating this system seamlessly, the sweat-activated batteries can directly power a patterned light-emitting diode and a multiplexed sweat biosensor, while wirelessly transmitting data to a user interface via Bluetooth. This strategic design offers safety warnings and continuous real-time health monitoring for night walking or running. This work paves the way for the development of an efficient and sustainable energy-autonomous electronic fabric system tailored for individual health monitoring.

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Highly power-density sweat-activated PANI/SWCNTs||Zn fiber battery has been fabricated by rapid reduction of emeraldine salt to leucoemeraldine. Through seamless system integration, the thus-fabricated sweat-activated battery pack can power a multiplexed sweat biosensor, demonstrating the feasibility of a sustainable energy-autonomous electronic fabric system for continuous individual health monitoring.

The development of biomimetic scaffolds that can promote osteogenic induction and vascularization is of great importance for the repair of large bone defects. In the present study, inorganic bioactive glass (BG) and organic polycaprolactone (PCL) are effectively combined by electrospinning and electrospray techniques to construct three-dimensional (3D) BG/PCL microfibrous spheres for the repair of bulk bone defects. The hybrid fibers, as well as the as-obtained 3D structure, can mimic the composition and architecture of native bone tissues. Furthermore, the BG/PCL microfibrous spheres show excellent biocompatibility and provide sufficient space and attachment sites for cell growth. The osteogenic differentiation of bone mesenchymal stem cells is also effectively facilitated when cultured on such hybrid microfibrous spheres. In vivo investigation utilizing rat femoral condyle bone defect models demonstrates that the BG/PCL microfibrous spheres loaded with bone mesenchymal stem cells can induce angiogenesis and promote the upregulation of bone-related protein expression, thus effectively facilitating bone regeneration at the defect site. The collective findings indicate that such BG/PCL hybrid microfibrous spheres have the potential to be effective carriers of stem cells. The microfibrous spheres loaded with stem cells have promising potential to be utilized as implantable biomaterials for the repair of bone defects.

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Excess biological fluids around skin wounds can lead to infections and impede the healing process. Researchers have extensively studied dressings with varying water contents for wound care. However, hydrophilic and hydrophobic-hydrophilic dressings often face challenges such as slow fluid transfer and excessive retention. This study introduces an innovative approach involving the use of superhydrophobic–hydrophobic–hydrophilic dual-gradient electrospun nanofibers to form a 3D biomimetic nanofiber scaffold (3D BNSF). The 3D BNSF is composed of hydrophobic polycaprolactone and thermoplastic polyurethane, along with antibacterial, superhydrophobic nano-chitin particles. In vitro and in vivo experiments have demonstrated that this scaffold exhibits excellent antibacterial properties and compatibility with cells, facilitating complete wound healing and regeneration. This study offers a new perspective on the targeted acceleration of wound healing, with the potential to become an alternative strategy for clinical applications.

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Alternating current electroluminescent (ACEL) fibers with wearable characteristics, such as flexibility, light weight, stitchability and comfort, are emerging in textile displays for daily applications. To construct efficient ACEL fibers, a judiciously designed and low-cost electrode is also extremely important but seems to receive less attention. Inspired by fiber dyeing, we propose a method that employs non-noble metals to design fiber electrodes by constructing microconductive channels inside commercial fibers. This method relies on the window period formed by the glass transition temperature of the PAN fibers, which is sufficiently flexible to extend to mass production at a low cost (approximately US$ 1.86/kg). The resulting ACEL fibers interwoven with a transparent fiber electrode formed a textile display with an acceptable luminescence performance of 46 cd·m⁻² (160 V). Notably, a visual feedback e-textile (VFET) was constructed by integrating fiber sensors, which demonstrates the concept of wearable real-time visual monitoring and interaction. Compared with their individual counterparts, VFET has been conveniently and efficiently for visual monitoring, communication, and interaction, i.e., the visualization of physiological parameters (heartbeat, respiration, etc.) and nonverbal communications (literal or cryptographic) for special groups and specific scenes.

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Thick, flexible electrodes are essential to simultaneously achieving flexibility and high energy density; however, mechanical failure and the sluggish movement of ions and electrons both restrict their application. Here, a thick electrode reinforced by a stainless-steel (SS) fiber three-dimensional (3D) current collector is proposed that simultaneously attains unprecedented flexibility and a high energy density. This ultra-flexible electrode is prepared by a thermally induced phase separation process. Its meso/macroporosity enhances ionic conductivity, and the 3D fiber reinforcement enhances interfacial adhesion, flexural durability, and electrical conductivity. Owing to these advantages, the fiber-reinforced electrode has a minimum bending radius of 3 mm owing to its high yield strain (13%) and attains a high energy density of 500 Wh·L⁻¹, which is considerably higher than that of previous flexible batteries (100–350 Wh·L⁻¹). In contrast with the same electrode coated on metal foil, which suffers from delamination, the fiber-reinforced electrode is delamination-free and outperforms in rate capability and cycling performance. Unlike conventional current collectors (foil, mesh, or foam), the SS fiber can be tailored to be distributed throughout the electrode and to fit the electrode form factor. Fiber-reinforced electrodes are also excellent at creating 3D free-form batteries, which are difficult to fabricate with conventional electrode structures.

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