Advanced Fiber Materials最新文献

The exploration of high-efficiency transition metal–nitrogen–carbon (M–N–C) catalysts is crucial for accelerating the kinetics of oxygen reduction/oxygen evolution reactions (ORR/OER). Fine-tuning the distribution of accessible metal sites and the correlated triphase interfaces within the M–N–C catalysts holds significant promise. In this study, we present an integrated electrocatalyst comprised of tip-enriched NiFe nanoalloys encapsulated within N-doped carbon nanotubes (NiFe@CNTs), synthesized using an in-situ wet-electrochemistry mediated approach. The well-defined NiFe@CNTs catalyst possesses a porous heterostructure, synergistic M–N_x–C active sites, and intimate micro interfaces, facilitating accelerated redox kinetics. This leads to exceptional OER/ORR activities with a low overall ΔE of 630 mV. Experimental results and density functional theory calculations unveil the predominant electronic interplay between the apical bimetallic sites and neighboring N-doped CNTs, thereby enhancing the binding of intermediates on NiFe@CNTs. Molecular dynamics simulations reveal that the local gas–liquid environment surrounding NiFe@CNTs favors the diffusion/adsorption of the OH⁻/O₂ reactants. Consequently, NiFe@CNTs contribute to high-performance aqueous Zn–Air batteries (ZABs), exhibiting a high gravimetric energy density (936 Wh kg_Zn^–1) and superb cycling stability (> 425 h) at 20 mA cm^–2. Furthermore, solid-state ZABs based on NiFe@CNTs demonstrate impressive electrochemical performance (e.g., peak power density of 108 mW cm⁻², specific energy of 1003 Wh kg_Zn^–1) and prominent flexibility. This work illuminates a viable strategy for constructing metal site-specific, cobalt-free, and integrated M–N–C electrocatalysts for multifunctional catalysis and advanced/flexible energy storage applications.

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Waterborne organic pollutants pose significant threats to ecosystems and the health of billions worldwide, presenting a pressing global challenge. Advanced oxidation processes (AOPs) offer promise for efficient wastewater treatment, yet the efficacy and the reliability of current environmental catalysts hinder their widespread adoption. This study developed an as-cast nanostructured glassy fiber capable of rapidly activating persulfate and achieved the degradation of diverse organic contaminants within 60 s using the as-prepared fiber. The material is relatively robust and can be reused about 40 times. The exceptional catalytic performance of the fibers stemmed from their low atomic coordination numbers, which facilitated the generation of numerous unsaturated active sites and accelerated radical production rates through a one-electron transfer mechanism. Additionally, the glassy-nanocrystalline heterogeneous interface, achieved through our proposed nanostructuralization approach, exhibited electron delocalization behavior. This enhanced persulfate adsorption and reduced the energy barrier for heterolytic cleavage of peroxy bonds. These findings present a novel avenue for the rational structural design of high-performance environmental catalysts for advanced water remediation.

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Respiration is a critical physiological process of the body and plays an essential role in maintaining human health. Wearable piezoelectric nanofiber-based respiratory monitoring has attracted much attention due to its self-power, high linearity, noninvasiveness, and convenience. However, the limited sensitivity of conventional piezoelectric nanofibers makes it difficult to meet medical and daily respiratory monitoring requirements due to their low electromechanical conversion efficiency. Here, we present a universally applicable, highly sensitive piezoelectric nanofiber characterized by a coaxial composite structure of polyvinylidene fluoride (PVDF) and carbon nanotube (CNT), which is denoted as PS-CC. Based on elucidating the enhancement mechanism from the percolation effect, PS-CC exhibits excellent sensing performance with a high sensitivity of 3.7 V/N and a fast response time of 20 ms for electromechanical conversion. As a proof-of-concept, the nanofiber membrane is seamlessly integrated into a facial mask, facilitating accurate recognition of respiratory states. With the assistance of a one-dimensional convolutional neural network (CNN), a PS-CC-based smart mask can recognize respiratory tracts and multiple breathing patterns with a classification accuracy of up to 97.8%. Notably, this work provides an effective strategy for monitoring respiratory diseases and offers widespread utility for daily health monitoring and clinical applications.

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Nociceptive-selective analgesia is often preferred over traditional methods, providing effective pain relief with minimum systemic side effects.The quaternary lidocaine derivative QX-314, is a promising local anesthetic for achieving selective analgesia. However, due to its inability to penetrate the cell membrane, its efficacy is limited to intracellular administration. In this study, we aimed to develop an injectable electrospun fiber-hydrogel composite comprising QX-314-loaded poly(ε-caprolactone) electrospun fiber and capsaicin (Cap)-loaded F127 hydrogel (Fiber-QX314/Gel-Cap composite) for long-term and nociceptive-selective analgesia. The sequential and sustained release mechanism of Cap and QX-314 helped remarkably extend the sensory blockade duration up to 44.0 h, and prevent motor blockade. Specifically, our findings indicated that QX-314 can traverse the cell membrane through the transient receptor potential vanilloid 1 channel activated by Cap, thus targeting the intracellular Na⁺ channel receptor to achieve selective analgesia. Moreover, the composite effectively alleviated incision pain by suppressing c-Fos expression in the dorsal root ganglion and reducing the activation of glial cells in the dorsal horn of the spinal cord. Consequently, the Fiber-QX314/Gel-Cap composite, designed for exceptional biosafety and sustained selective analgesia, holds great promise as a non-opioid analgesic.

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Injectable composite comprising QX-314-loaded electrospun fiber and capsaicin-loaded thermosensitive hydrogel sequentially releasing drugs for prolonged and nociceptive-selective local analgesia.

It is a worldwide challenge to achieve an efficient cleaning of heavy oil at ambient temperature. Conventional cleanup methods for high-viscosity oil spills exhibit low absorption efficiency and have severe practical operating limits. Herein, inspired by the passive transport process in the Salvinia cucullata, a solar-heated and joule-heated textile-based absorber using the scalable electrostatic flocking technique. Benefiting from the efficient photothermal and electrothermal conversion effects, the textile-based absorber, with oleophilic and aligned channels, facilitates thermal conduction and hence enhances heavy oil absorption. The absorber is highly efficient for organic solvents (chloroform and dichloromethane) and low-viscosity oils (silicone oil, gasoline, and diesel oil). The surface temperature of the textile absorber rises rapidly to 92 °C (114 °C) in 120 s (240 s) under one sun irradiation (or 5 V voltage), resulting in a sharp drop in the viscosity of the heavy oil and then achieving an ultrahigh absorption rate (2647 kg h⁻¹ m⁻²) and fast equilibrium time (25 s). Rapid absorption rate significantly reduces spill cleanup time and spill spreading area, hence alleviating the environmental harm caused by oil spills as much as possible. The proposed solar-heated and joule-heated textile-based absorbers with aligned channels show great potential for efficient heavy oil absorption.

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The advancement of integrated circuits has made it easier to reduce the size of increasingly potent wearable electronic devices. However, it is still difficult to seamlessly integrate electronic systems enabling unrestricted human behavior into wearable gadgets. The procedure of creating fiber devices by twisting fiber electrodes and incorporating them into textile systems is exhibited in recent work. These textile systems are highly resilient and flexible, which makes them ideal for various wearable applications, i.e., thread lithium-ion batteries (TLIBs), multi-ply sensing threads (MSTs), and thread electroluminescent devices (TELDs).

Personalized wound dressings with on-site deposition, exudate suction, and reproducible sterilization are urged for treating diabetic wounds. Herein, we have developed nanofiber membranes incorporating a V-shaped photosensitizer (VPS), a donor-acceptor-donor type organic semiconductor with indacenodithienothiophene (IDTT) as the electron-donor and triphenyleno[1,2-c:7,8-c′]bis([1,2,5] -thiadiazole) (TPTz) as the electron-acceptor, for multifunctional wound dressing. The VPS-incorporated nanofiber membranes are in situ deposited on rough wounds by using a handheld electrospinning device, which offers full coverage and better affinity than gauze to stop bleeding and suck exudate rapidly. They are breathable, waterproof, and have bacteria repelling capacity due to their hydrophobicity and negative charges. Upon light irradiation, the VPS in nanofibers undergoes low aggregation-caused quenching and retains high fluorescence and reproducible photodynamic sterilization towards both Gram-positive and Gram-negative bacteria. The nanofiber dressing also promotes cell adhesion and proliferation and exhibits high security in blood biochemistry and hematology. With the above merits, the nanofiber membranes greatly reduce the expression of tumor necrosis factor α and interleukin 6 in serum and wound tissues, expediting the wound healing process. These wound dressings combine the benefits of in situ electrospinning, fiber membrane, and VPS, and will provide strategies for emergency medical operations.

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Wearable electronics, poised to revolutionize real-time health monitoring, encounter significant challenges due to sweat accumulation, including skin irritation, peeling, short circuits, and corrosion. A groundbreaking study published in Nature presents a sustainable solution: three-dimensional (3D) liquid diodes that effectively pump sweat away, thereby maintaining the wearables’ breathability and stable sensing of biometrics or environments without getting messed up by perspiration. This advancement has immense potential for the development of comfortable and skin-friendly intelligent wearable technologies that seamlessly incorporate sophisticated electronics even in sweaty conditions.

Wearable strain sensors (WSSs) have found widespread applications, where the key is to optimize their sensing and wearing performances. However, the intricate material designs for developing WSSs often rely on costly reagents and/or complex processes, which bring barriers to their large-scale production and use. Herein, a facile and affordable (material cost of < $0.002/cm²) method is presented for fabricating conductive bandage (CB)-based WSSs by electrospraying a carbon nanotube (CNT) layer on commercial self-adhesive bandages with excellent biosafety, stretchability, mechanical compliance, breathability and cost effectiveness. The wrinkled and fibrous structures of self-adhesive bandages were rationally leverage to control the geometry of CNT layer, thereby ensuring tunable mechanoelectrical sensitivities (gauge factors of 2 ~ 850) of CBs. Moreover, a strain-sensing mechanism directly mediated by the highly wrinkled microstructure is unveiled, which can work in synergy with a training-loosened-fibrous microstructure. The excellent performance of CBs for monitoring full-range strain signals in human bodies was further demonstrated. CBs would possess great potential for being developed into WSSs because of their outstanding cost-performance ratio.

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