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Piezoelectric fiber yarns produced by electrospinning offer a versatile platform for intelligent devices, demonstrating mechanical durability and the ability to convert mechanical strain into electric signals. While conventional methods involve twisting a single poly(vinylidene fluoride-co-trifluoroethylene)(P(VDF-TrFE)) fiber mat to create yarns, by limiting control over the mechanical properties, an approach inspired by composite laminate design principles is proposed for strengthening. By stacking multiple electrospun mats in various sequences and twisting them into yarns, the mechanical properties of P(VDF-TrFE) yarn structures are efficiently optimized. By leveraging a multi-objective Bayesian optimization-based machine learning algorithm without imposing specific stacking restrictions, an optimal stacking sequence is determined that simultaneously enhances the ultimate tensile strength (UTS) and failure strain by considering the orientation angles of each aligned fiber mat as discrete design variables. The conditions on the Pareto front that achieve a balanced improvement in both the UTS and failure strain are identified. Additionally, applying corona poling induces extra dipole polarization in the yarn state, successfully fabricating mechanically robust and high-performance piezoelectric P(VDF-TrFE) yarns. Ultimately, the mechanically strengthened piezoelectric yarns demonstrate superior capabilities in self-powered sensing applications, particularly in challenging environments and sports scenarios, substantiating their potential for real-time signal detection.

Electrospinning is a cost-effective but very intricate method of producing polymeric nanofibers at room temperature. Unfortunately however, it is extremely difficult to predict the diameter or other properties of the fibers produced via electrospinning a prior. In this paper, we present a new approach to simulate fiber formation during electrospinning. Our work builds on the mathematical framework that was originally developed by Reneker and Yarin in 2000. Our approach incorporates the 3D electrostatic field that surrounds the fiber in a Lagrangian discrete particle tracking algorithm that tracks the trajectory of the fiber in air and predicts its deposition velocity and diameter. We investigate the effects of electrostatic field spatial variation on fiber electrospinning and compare our results with those obtained using a constant electrostatic field, the traditional approach, and with experiments (conducted using polyurethane). We considered three different electrospinning configurations of single-needle-plate-collector, single-needle-drum-collector, and two-needles-drum-collector to investigate how different electrostatic fields impact fiber formation. The computational model developed in this work helps to advance the current state of the art in modeling the electrospinning process. [ABSTRACT FROM AUTHOR]

Electrospinning is an important technique to fabricate nanofibers. In recent years, near-field electrospinning (NFES) has been developed to enhance the control of nanofiber deposition compared to conventional electrospinning, achieved by reducing the operating distance and electric field. This enables the construction of high-aspect ratio 3D structures in a self-aligned, layer-by-layer manner. However, the alignment of fiber deposition can be hindered by charge accumulation in the polymer fibers. Furthermore, a theoretical understanding of the underlying fiber deposition mechanism is still lacking. Herein, we present a numerical model for studying the charge transport, dissipation, and accumulation of NFES polymer fiber deposition. The model reveals that the presence of a trapped state in polymeric materials imposes limitations on the quality of charged fiber deposition. Moreover, the effect of different substrate materials on charge dissipation in fiber deposition is studied. To validate the model, we compare the simulation results with NFES experiments, demonstrating qualitative agreement. We also analyze the effect of the fiber materials and experimental parameters on the printing quality. This model provides an approach to analyze and optimize the operating parameters of NFES to achieve precise and stable nanofiber deposition. [ABSTRACT FROM AUTHOR]

Encapsulating curcumin (CUR) in nanocarriers such as liposomes, polymeric micelles, silica nanoparticles, protein-based nanocarriers, solid lipid nanoparticles, and nanocrystals could be efficient for a variety of industrial and biomedical applications. Nanofibers containing CUR represent a stable polymer-drug carrier with excellent surface-to-volume ratios for loading and cell interactions, tailored porosity for controlled CUR release, and diverse properties that fit the requirements for numerous applications. Despite the mentioned benefits, electrospinning is not capable of producing fibers from multiple polymers and biopolymers, and the product's effectiveness might be affected by various machine- and material-dependent parameters like the voltage and the flow rate of the electrospinning process. This review delves into the current and innovative recent research on nanofibers containing CUR and their various applications. [ABSTRACT FROM AUTHOR]

In this study, Poly(ethylene terephthalate) (PET) fibres were copolymerised with a mixture of acrylamide (AAm), 2 -hydroxypropyl methacrylate (2-HPMA) monomers in the presence of a mixture of initiators benzoyl peroxide (Bz2O2) −4, 4-azobis-4-cyano-valeric acid(ACV). After determining the optimal graft condition, solution electrospinning was performed. Optimal electrospinning conditions were obtained at (V = 10 kV, TFA/DCM = 4/1, distance from nozzle = 12.5 cm).The best adsorption conditions were determined by batch technique. The adsorption process was in good agreement with the Langmuir isotherm model and the Pseudo-second-order kinetic model. The mentioned findings confirm the homogeneity, monolayer and chemical nature of the adsorption process. Grafted nanofibers had a good performance in removing Ni2+ ions from industrial effluents in Charmshahr and Ghods industrial town. Thermodynamic studies have shown that the process is endothermic, spontaneous and is associated with increasing entropy. [ABSTRACT FROM AUTHOR]

Nonwoven materials are fashioned from polyimide (PI) and its copolymer derivative (urethane–imide) (CPUI) through the formation of electrical fibers, referred to as electrospinning (ES). Diaminobiphenyl ether (DABPE) and pyromellitic anhydride (PMA) are chosen as monomers in the synthesis of polyimide. Diamine dianhydride and toluene di-isocyanate (TDI) are used in the synthesis of copoly(urethaneimide), as is polycaprolactone (Mn = 2000). A nonwoven polyimide material is obtained from an aqueous–ethanolic solution of the triethylammonium salt of polyamide acid (SPAA) with subsequent thermal imidization of the nonwoven prepolymer at 250°C. A nonwoven material based on SPAA is obtained from a solution of copoly(urethaneamidoacid) in dimethyformamide (DMF) using a catalytic mixture consisting of triethylamine and acetic anhydride. Optimum conditions are selected for the formation of nonwoven fibers in electrospinning. The chemical structure of nonwovens is confirmed via IR spectroscopy. The morphology of the microstructure of nonwovens is studied by means of scanning electron microscopy (SEM). The thermal and mechanical properties of the obtained nonwovens are determined using TGA, DSC, and DMA, and their deformation and strength characteristics are determined. Membrane filtration properties of the obtained nonwovens are studied. It is concluded that nonwovens can be used as membranes that operate in nonaqueous organic media. [ABSTRACT FROM AUTHOR]

Oriented polyacrylonitrile (PAN) films were prepared and treated with hot stretching method to obtain higher degree of orientation. The PAN fiber membrane was infiltrated with thermoplastic polyurethane (TPU) to prepare oriented PAN membrane reinforced TPU composite membrane. The tensile properties of the composite material were studied, and the tensile strength, modulus, and toughness all increased with the increase of orientation. The interfacial miscibility between the matrix and nanofibers was observed using Raman spectroscopy, and morphology, properties, and reinforcement mechanism of the composite material were analyzed combining scanning electron microscopy technique. The results indicate as the orientation increases, the compatibility between the matrix and fibers improves, and the mechanical properties of the composite material also improved. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes, a food-borne pathogen capable of releasing biomarker 3-hydroxy-2-butanone (3H-2B), generally causes a serious threat to human health. Developing 3H-2B gas sensor with excellent performance is of great significance in the diagnosis and prevention of Listeria. Here, we have successfully fabricated Co-doped ZnO nanofibers gas sensor via an electrospinning method, which can be well used for real-time monitoring of Listeria. The results show that the Co-doped ZnO nanofibers have a wurtzite crystal structure and a nanofiber-like morphology with a diameter of 62 nm. The band gap (3.15 eV) of the Co-doped ZnO is significantly narrower than that of the pure ZnO (3.25 eV). The response (168) of the 0.5%Co-doped ZnO based sensor to 100 ppm 3H-2B at 305 °C is 5.37 times greater than that of the pure ZnO (31.3), with a high selectivity, a lower detection limit (100 ppb) and a short response time of 1 s. The enhanced gas sensing mechanism is ascribed to the depletion layer on the ZnO surface, a superposition effect of interface barrier, and the narrowed band gap of the ZnO. [Display omitted] [ABSTRACT FROM AUTHOR]

Fe-based perovskite without Co has a low thermal expansion coefficient and can be used as a solid oxide fuel cell (SOFC) cathode to ensure the thermal compatibility with the electrolyte; however, its further advancement is impeded by sluggish oxygen reduction reaction (ORR) dynamics. In this work, the electrospinning method and Cu doping strategy are employed to improve the microstructure and oxygen reduction kinetics of Pr 0.5 Ba 0.5 FeO 3-δ cathodes. The results show that Pr 0.5 Ba 0.5 Fe 0.8 Cu 0.2 O 3-δ has a unique fiber structure and high specific surface area, and the introduction of Cu facilitates the release of lattice oxygen, effectively increasing the oxygen vacancy content. The relaxation time distribution analysis and oxygen reduction reaction dynamics indicate that the oxygen adsorption-dissociation process is the main rate-limiting step in the oxygen reduction reaction of Pr 0.5 Ba 0.5 Fe 0.8 Cu 0.2 O 3-δ electrode materials. At 700 °C, the area-specific resistance (ASR) of the symmetric cell of Pr 0.5 Ba 0.5 Fe 0.8 Cu 0.2 O 3-δ fiber material is 0.071 Ω cm2, and the power density of the single cell reaches 988 mW cm−2, which shows good electrochemical output performance and long-term operational stability. The preparation of nanofiber cathodes with high specific surface area and porosity by electrospinning provides an effective strategy to enhance the electrocatalytic activity of the IT-SOFC cathode. [ABSTRACT FROM AUTHOR]

Facial masks available in the market are primarily made of non‐woven fabric. To extend their shelf life, preservatives, and essences are added to their ingredients. However, this practice has a significant impact on the environment and human health. As a result, consumers nowadays prefer to choose "Clean Beauty" products for their skincare routines. Herein, electrospinning technology was used to prepare a novel Janus nanofiber membrane comprising Polylactic acid/Polyvinylpyrrolidone (PLA/PVP) and Chitosan/Gelatin (CS/GEL), loaded with Gastrodia elata polysaccharide (GEP) and melatonin (MT). The Janus nanofiber facial mask is a solid mask that provides excellent moisturizing, antioxidant, and biocompatibility benefits. It can dissolve quickly and be absorbed by the skin, while the hydrophobic fiber helps slow down the rapid evaporation of water in the mask. This, combined with the Janus structure, helps delay the loss of water and allows for quick penetration, resulting in a long‐lasting moisturizing effect. Therefore, the Janus nanofiber facial mask is an ideal choice for solid facial masks and provides technical support for its application in this field. [ABSTRACT FROM AUTHOR]

In this study, chitosan (CH)/polyvinyl alcohol (PVA) hybrid nanofibers incorporating three distinct essential oils lemon, lime, and grapefruit were successfully obtained via the innovative electrospinning technique. Characteristics of the electrospinning polymeric mixture loaded with essential oils using variable ratios of CH/PVA were evaluated. The nanoencapsulation process of citrus essential oils was achieved with 47.67%–88.16% encapsulation efficiency. Notably, the thermal stability of the encapsulated essential oils experienced a significant enhancement after encapsulation. Scanning electron microscopy analysis revealed valuable insights, revealing that an increased amount of incorporated essential oil within the polymeric mixture solutions led to a reduction in the average fiber diameters. The resulting nanofibers demonstrated notable attributes such as antioxidant, tyrosinase inhibitory, and antibacterial activities. The present research demonstrates the ability of CH/PVA hybrid nanofibers obtained through an electrospinning process to preserve citrus essential oils properties quality and reveals a high potential application of nonencapsulated citrus essential oils in biomaterials, food packaging, and advanced cosmetic application. [ABSTRACT FROM AUTHOR]

This study presents a novel protective membrane, (0.8MnCuSnOx‐NaCl)@M, designed for high‐efficiency filtration of dust particles and carbon monoxide (CO) gas offers superior moisture resistance, air permeability, and catalytic functionality in high‐humidity underground settings. The membrane, incorporating tin oxide‐doped CuMnOx into polyvinylidene fluoride (PVDF) fibers with sodium chloride (NaCl), achieves 99.99% air filtration efficiency, 323.68 mm s−1 air permeability, and 92.5% CO catalytic filtration efficiency. Concurrently, the membrane exhibited exceptional hydrophobicity, characterized by a substantial water contact angle of 116.7°, negligible water staining, and a high hydrostatic pressure rating of 2035 Pa, suitable for humid environments. Furthermore, the water absorption profile of the membrane featured a diminished hydroxyl vibrational band, accompanied by a sustained CO conversion efficiency, attesting to its resistance to moisture‐induced deterioration. Computational fluid dynamics (CFD) simulations further clarify the membrane's filtration mechanism, indicating its potential for selective CO and particle filtration. This study provides a reliable idea for the development of moisture‐resistant fiber membranes with high efficiency for filtration of dust and CO. and underscores the synergy of experimental and theoretical approaches. [ABSTRACT FROM AUTHOR]

Approximately one in five individuals experience alveolar osteitis (AO) following wisdom tooth extraction. AO is characterised by loss of the blood clot from the tooth extraction socket leading to infection and pain, resulting in repeated hospital visits that impose a substantial burden on healthcare systems. Current treatments are sub-optimal; to address this we developed a novel drug-loaded mucoadhesive patch composed of dual electrospun polyvinyl pyrrolidone/Eudragit RS100 (PVP/RS100) and poly(N -isopropylacrylamide) (PNIPAM) fibres protected by a poly(ε-caprolactone) (PCL) backing layer. These patches demonstrated controlled release of the long-acting analgesic bupivacaine HCl and the anti-inflammatory drug prednisolone. Topical application of patches to tissue-engineered gingival mucosa showed that patch-released bupivacaine and prednisolone achieved sustained tissue permeation with 54.8 ± 3.3 % bupivacaine HCl and 65.8 ± 5.1 % prednisolone permeating the epithelium after 24 h. The drugs retained their functionality after release; bupivacaine HCl significantly (p < 0.05) inhibited veratridine-induced intracellular calcium flux in SH-SY5Y neuronal cells, while prednisolone significantly reduced gene expression of IL-6 (2-fold; p < 0.001), CXCL8 (5.1-fold; p < 0.01) and TNF-α (1.5-fold; p < 0.001) in stimulated THP-1 monocytes. Taken together, these data show that dual electrospun patches have the potential to provide a mucoadhesive covering to prevent blood clot loss while delivering pain relief and anti-inflammatory therapeutics at tooth extraction sites to prevent and treat AO. This study not only offers a future therapeutic pathway for AO but also contributes valuable insights into future advancements in drug delivery devices for periodontal or oral mucosal tissue. [Display omitted] • Mucoadhesive electrospun patch that simultaneously delivers pain relief and anti-inflammatory drugs. • Dual electrospun PVP/RS100 and PNIPAM microfibres achieve controlled drug release. • Patches reduce cytokine secretion in a 3D in vitro model of gingival inflammation. • Patch treatment blocks cell voltage-gated sodium channels for pain relief. [ABSTRACT FROM AUTHOR]

Vibrational spectroscopy allows the investigation of structural properties of pristine and doped poly(3-hexylthiophene-2,5-diyl) (P3HT) in highly anisotropic materials, such as electrospun micro- and nanofibers. Here, we compare several approaches for doping P3HT fibers. We have selected two different electron acceptor molecules as dopants, namely iodine and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). In the case of iodine, we have explored the doping of the fibers according to several different procedures, i.e., by sequential doping both in vapors and in solution, and with a novel promising one-step method, which exploits the mixing of the dopant to the electrospinning feed solution. Polarized infrared (IR) spectroscopy experiments prove the orientation of P3HT chains, with the polymer backbone mainly running parallel to the fiber axis. After doping, P3HT fibers show very strong and polarized doping-induced IR active vibrations (IRAVs), which are the spectroscopic signature of the structure relaxation induced by the charged defects (polarons), thus providing an unambiguous proof of the effective doping. Raman spectroscopy complements the IR evidence: The Raman spectrum shows a clearly recognizable shift of the main band, the so-called effective conjugation coordinate band, in the doped samples. A simple protocol, which quantifies the evolution of the IRAV bands with time, allows monitoring of the doping stability over time and confirms that F4TCNQ is by far superior to iodine. [ABSTRACT FROM AUTHOR]

Summary: Black mulberry extract (BME) is rich in phenolics; however, their health benefits are restricted by their instability and poor absorption in the small intestine. Liposomal BME‐loaded pullulan/pectin nanofibers were developed to enhance the in vitro bioaccessibility of BME. The liposomes with BME (0.8%, w/v), were produced by the thin‐film hydration and ultrasonication method with a size of 76.41 ± 1.23 nm and encapsulated 79.40 ± 0.99%.of the BME. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) images showed that the uniform distribution of liposomes within the defect‐free fiber structure. Liposomal BME loading elevated the mucoadhesiveness of the nanofibers compared to free BME loading. Liposomal BME‐loaded nanofiber demonstrated a nearly two‐fold increase in the bioaccessibility of anthocyanins. The cellular release of all four different anthocyanins by Caco‐2 cells was significantly higher (3.92%–10.50%) in liposomal BME‐loaded nanofiber. Therefore, liposomal nanofibers show great potential as a method for delivering phenolics, specifically anthocyanins. [ABSTRACT FROM AUTHOR]

As an emerging sensor technology, the flexible piezoelectric sensor has a very wide range of applications. Therefore, in order to achieve better output performance of flexible piezoelectric sensors, it is particularly important to choose piezoelectric materials with good piezoelectric performance. In this study, polyvinylidene difluoride (PVDF)/polyvinyl chloride (PVC)/graphene oxide (GO) composite fibers were fabricated by the electrospinning technique. FTIR and XRD studies showed that the β-phase content of the composite fibers reached 94.6% with the addition of PVC and GO. The mechanical properties of the composite films doped with PVC and GO were also significantly improved. The sensitivity of the sensor made of composite fibers doped with 0.2 % GO reached 16.2 V/N in the range of 1 N. Compared to other systems, the PVDF/PVC/GO system showed excellent piezoelectric output performance with output voltages of up to 6 V and 3 μA by the action of palm tapping. And after 2000 cycles, the sensor system showed good stability. The resulting flexible piezoelectric sensor can monitor actions such as impacts and bending and has great potential for motion monitoring. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile (PAN) membranes have garnered significant due to their exceptional properties and versatility. PAN membranes are synthesized via fabrication techniques such as phase inversion and electrospinning and possess PAN qualities of excellent mechanical strength, thermal stability, and chemical resistance. Modifications like surface treatment, fabrications of composites, blends, and grafting are quite popular in adapting PAN membranes to diverse applications and improving their performance and qualities. These modifications provide incredible membrane customizability and help tailor specific properties according to performance requirements. As such, PAN membranes have found applications in multiple areas like oil–water separation, heavy metal ion removal, water purification, hemodialysis, lithium-ion batteries, and many more. The paper throws light on various fabrication techniques for PAN membranes and comprehensively reviews various modifications of PAN membranes along with their diverse applications. Additionally, recent advancements and emerging trends in PAN membrane research are discussed, providing insights into future directions for innovation and development. [ABSTRACT FROM AUTHOR]

The one-dimensional structure preparation by electrospinning method is one of the most important especially since it can get fine diameters of fibers. Poly (vinyl alcohol) and (PVA)/polyethylene glycol (PEG) were mixed to get the blend and doped with different ratios (0.001, 0.002, 0.003) wt.% of calcium fluoride (CaF2) to get nanocomposite were fabricated using the electrospinning method at RT and voltage of 23 kV. Structural and optical properties were studied and the antibacterial activity was examined. The result of SEM analysis showed that the polymer blend and doped samples produced a random distribution with fine fibers at an average diameter range before CaF2 addition to be 68.97 nm and after CaF2 addition for each sample to be 45.76, 68.71, and 98.45 nm with a smooth surface. XRD analysis confirmed the existence of semi-crystalline PVA and PEG aggregates, and the CaF2 cubic crystalline phase appears when an additive of CaF2 nanoparticles up to 0.003 g. Absorbance spectra were recorded in the wavelength range of (200–800) nm. Absorption increased by two times when doping of CaF2 increased to 0.003 wt.%. The optical energy gap of fabricated films decreased with increasing CaF2 nanoparticles from (3.6–3.3) eV, while the refractive index increased. Increasing the content of NPs for the (PVA-PEG:CaF2) nanofibers mixture leads to an increase in the diameter of the inhibition zone for Escherichia coli for antibacterial activity. [ABSTRACT FROM AUTHOR]

In this study, multifunctional wound and burn dressing material was developed to cover open wounds and protect them from external effects. Trimethylolpropane ethoxylate-170 (TMPE)-based polyurethane/polycaprolactone (PU/PCL) dressing materials were prepared with high biocompatibility and ordered nanofiber formation. Prepared PU/PCL dressing materials also contain allantoin additive to accelerate wound healing. Polyurethane structures were synthesized using solution polymerization technique from hexamethylene diisocyanate, polyethylene glycol-200, TMPE and Tween-40 monomers in different mole ratios. The obtained polyurethanes and dressing materials were characterized structurally, thermally and morphologically. Then, PCL, allantoin and gentamicin sulfate were added to these PU structures and converted into wound dressing materials by electrospinning technique. The allantoin release, mechanical analysis, antibacterial properties and biodegradability of the produced dressing materials were investigated. The obtained PU/PCL dressing materials were seen as flexible, durable and structural stable. These dressing materials have fiber diameter of approximately 500 nm. The tensile strength and Young's modulus of PU/PCL dressing materials are 2.22 ± 0.39 MPa and 1.04 ± 0.11 MPa. They released allantoin regularly for about 70 h and showed antibacterial properties. In addition, the prepared dressing materials have grade 1 biocompatibility. As a result, these dressing materials provide a good alternative to existing wound dressing materials. [ABSTRACT FROM AUTHOR]

The development of effective wound dressings is critical for enhancing patient outcomes in both acute and chronic wound care scenarios. In this research, electrospun nanofibrous scaffolds were fabricated from poly(ε-caprolactone) (PCL), enhanced with curcumin and reduced graphene oxide (RGO) to optimize their biomedical applications, particularly in wound healing. The resulting scaffolds were rigorously characterized through scanning electron microscopy, contact angle measurements, water uptake capacity, and water vapor transmission rate assays. The biocompatibility of these novel nanofibers was affirmed through MTT assays. Antibacterial tests confirmed the scaffolds' ability to inhibit both Gram-negative and Gram-positive bacteria, with inhibition zones measuring up to 9.9 mm for S. aureus and 9.2 mm for E. coli. Additionally, scaffolds containing curcumin exhibited significant antioxidant activity, achieving up to 40% radical scavenging efficiency. The study further revealed the scaffolds' capability for sustained drug release, with an initial burst release within the first 12 hours followed by a gradual release over 168 hours. Overall, the PCL-curcumin-RGO electrospun mats demonstrated considerable potential for biomedical applications, notably in the field of wound dressings, due to their enhanced antibacterial, antioxidant, and biocompatible properties. [ABSTRACT FROM AUTHOR]

Zirconium boride (ZrB2) whiskers hold significant potential for toughening ultra‐high temperature ceramics (UHTCs). Yet, their fabrication remains challenging due to limited knowledge of the microstructure evolution. Herein, high‐purity ZrB2 whiskers were successfully prepared by electrospinning combined with carbothermal reduction. Specifically, a precursor solution containing Zr–O–C–B networks stabilized through hydrogen bonds with polyvinyl pyrrolidone was synthesized as a spinnable ZrB2 precursor. High‐purity ZrB2 whiskers with a diameter of ca. 200 nm and a length of 5–10 µm were obtained by precise heat treatment of ZrB2 precursor fibers. In this process, ZrO2 grains formed initially and transformed into ZrB2 grains through carbothermal reduction, which further converted into ZrB2 whiskers through a solid‐liquid‐solid mechanism. To testify to the toughening effect for UHTCs, the ZrB2 whiskers were added into ZrB2 powders and followed by sintering. This strategic addition of 5 wt% ZrB2 whiskers led to a 19% enhancement in the fracture toughness of ZrB2 bulk. This study illuminated the preparation strategy and formation mechanism for ZrB2 whiskers and their application for toughening UHTCs. [ABSTRACT FROM AUTHOR]

Although traditional dental-implant approaches have served as primary solutions, they are limited by infection risks, complications, and prolonged failures. Hybrid electrospun nanofiber matrices based on biomaterials have emerged as compelling alternatives for dental-tissue regeneration, offering direct cell-matrix contact and facile modification to incorporate anti-inflammatory, angiogenic, antimicrobial, and osteogenic properties. In this review, we discuss the advancements in hybrid nanofiber matrix-based approaches in dental-tissue engineering over the past five years (2019–2023). Beginning with an exploration of dental tissues and tooth structures, we discuss the innovative strategies in each study, including fabrication methods, physicochemical and biological properties, and osteogenic potential. We anticipate that ongoing research will enable the widespread application of innovative biomaterials and nanofiber matrices in future dental therapies. [ABSTRACT FROM AUTHOR]

The research project focuses on conducting an in vitro comparison between sodium alginate and chitosan electrospun nanofibers for moist wound management. These fabricated nanofibers were incorporated with levofloxacin (Lev) as a model drug to investigate their release behavior. The study included a comprehensive examination of the physicochemical, thermal, antibacterial, and cytocompatibility properties of these nanofibers. Both sodium alginate (SA-L) and chitosan (CS-L) nanofibers were successfully produced with a homogeneous and defect-free structure. XRD and FTIR analyses were conducted to validate the incorporation of Lev in the nanofibers. In terms of liquid absorption capacity, it was observed that sodium alginate nanofibers outperformed chitosan nanofibers, exhibiting absorption capacities of 5.9, 5.88, and 7.1 g/g for PBS, solution A, and DI, respectively, for SA-L, compared to 5.27, 4.42, and 5.3 g/g for CS-L nanofibers. This superior absorption ability in SA-L nanofibers may be attributed to the inherent gel-forming properties of alginate in aqueous environments. Furthermore, the release kinetics indicated that SA-L nanofibers exhibited faster drug release compared to CS-L nanofibers, which could be attributed to alginate's natural gel-forming tendency in aqueous mediums. Both SA-L and CS-L nanofibers demonstrated remarkable efficacy against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa), with CS-L nanofibers displaying larger inhibition zones in agar diffusion tests due to chitosan's inherent antibacterial properties. Moreover, cytocompatibility assessments using the HaCat cell line revealed that the prepared nanofibers were biocompatible and non-toxic. Interestingly, CS-L nanofibers exhibited superior cell proliferation when compared to SA-L nanofibers, potentially attributed to the inherent positively charged amine groups which enhance proliferation and migration of negatively charged keratinocytes. [ABSTRACT FROM AUTHOR]

In this paper, the Optimization Design and properties of polyvinyl alcohol (PVA)/gelatin (GEL) nanofibers were studied. Different mass fractions of PVA (4, 5, 6 and 7 wt%), GEL (1, 2, 3 and 4 wt%), different spinning distances (8, 15, 22 and 29 cm), different voltages (10, 17, 24 and 31 kV), and different spinning speeds (0.1, 0.2, 0.3 and 0.4 mL) were designed into five factors and four levels by orthogonal experiments. The conductivity and viscosity of the mixed solution was tested. The PVA/GEL nanofibers were prepared by electrospinning and the morphology of composite nanofibers was observed under electron microscope. Finally, the PVA/GEL nanofiber film was tested by infrared spectroscopy and X-ray diffraction. The results showed that the infrared spectral groups and X-ray diffraction angles of nanofibers with different PVA/GEL ratios have little change. PVA/GEL nanofiber materials have great application potential in the field of biomedicine. [ABSTRACT FROM AUTHOR]

This research paper investigates new and first insights into the magnetic and magnetocaloric properties of one-dimensional (1D) cobalt ferrite CoFe2O4 (CFO) nanofibers (NFs) fabricated using a sol–gel-based electrospinning technique, focusing in particular on their behavior at low temperatures for specific applications. The microstructural, structural, magnetic, and magnetocaloric properties of the calcined CFO NFs were explored. The microstructure of the NFs, with an average diameter of 210 nm, was examined by scanning and transmission electron microscopy (SEM, TEM). The x-ray diffraction (XRD) of the CFO NFs showed a pure cubic close-packed (ccp) spinel crystalline structure with the Fd 3 ¯ m space group. The Raman spectroscopic studies further confirm the cubic inverse spinel phase. The magnetic properties were explored as a function of temperature, ranging from 10 K to 300 K, and ferromagnetic behavior was observed with the highest saturation magnetization of 75.87 emu/g and coercivity of 723 Oe at room temperature. The variation of the magnetic entropy was measured indirectly using the Maxwell approach with an increasing magnetic field. A maximum of Δ S = 1.71 J/K was reached around 32 K. At 180 K, the associated adiabatic temperature change, ΔTmax, was 0.93 K, with a large RCP value of 7.58 J/kg, which is reasonably high for the corresponding nanoparticles (NPs). This work suggests that 1D CFO NFs offer a promising route for the production of nanostructured magnetic materials, potentially impacting various electronic and electromagnetic device applications at low temperatures. [ABSTRACT FROM AUTHOR]

Palladium plays an important role in modern industry, agriculture and medicine. The direct discharge of palladium results in serious environmental pollution and loses of precious palladium metal. Herein, kaolin/chitosan hybrid nanofibers were successfully prepared to recover Pd2+ cations from aqueous solution. Chitosan and kaolin mixture was first electrospun into nanofibers with citric acid as the in situ crosslinking agent and poly(ethylene oxide) as the co-spinning polymer. Then, the chitosan molecules in these hybrid nanofibers were in situ crosslinked by critic acid at elevated temperatures to endow these nanofibers with excellent solvent resistance. Their structure characterization was conducted by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and positron annihilation lifetime spectroscopy (PLAS). The adsorption performances of these fibrous adsorbents were carefully investigated and optimized (e.g. kaolin content, temperature, pH of solution and initial Pd2+ concentration). The adsorption results demonstrated that incorporation of kaolin powders into the nanofibers could enhance the adsorption capacity from 31 mg/g to 64 mg/g. Thermodynamic parameters studies revealed the endothermic and spontaneous natures of the adsorption process of Pd2+ cations on these hybrid nanofibers. The Pd2+ adsorption behavior of this fibrous adsorbent fitted well with the second-order kinetic model, suggesting the chemical adsorption behavior of Pd2+ cations on this fibrous adsorbent. Moreover, this fibrous adsorbent can be easily regenerated and reused at least three times without significant loss of initial adsorption capacities. These results clearly indicate that this fibrous chitosan/kaolin hybrid absorbent holds great potential in the recovery of precious palladium cations from aqueous solution. [ABSTRACT FROM AUTHOR]

The objective of this work was to fabricate nanofibres composed of polycaprolactone (PCL) and κ‐carrageenan (kC) by employing an anionic surfactant, sodium bis(2‐ethylhexyl) sulfosuccinate (AOT). This study examined the role of the surfactant in PCL/kC/AOT (hybrid) nanofibre preparation using SEM, AFM, Fourier transform infrared spectroscopy, XRD and DSC. The wettability and water uptake percentage of the nanofibres were investigated. An antimicrobial study was conducted against bacterial strains using a colony‐counting assay, and changes in bacterial morphology were monitored using TEM. The results demonstrated that the hybrid nanofibres had a uniform and smooth structure, which might be attributed to the improved compatibility between polymers in the presence of the surfactant. The incorporation of AOT in the matrix resulted in a reduction in the mean fibre diameter and surface roughness. The hybrid nanofibres increased water absorbency is evidence of their high hydrophilicity, which can be explained by the simultaneous impact of kC and AOT. The hybrid nanofibres exhibited effective activity against Staphylococcus aureus and Escherichia coli. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Piezoelectric materials have garnered significant interest owing to width range of applications in sensing and energy harvesting by converting environmental mechanical energy to electricity. Improving the performance of piezoelectric nanogenerators (PENGs) is an important challenge to develop these devices. Herein, a novel method was used to enhance the piezoelectricity of the PENGs based on PVDF NFs (polyvinylidene fluoride nanofibers) and BaTiO3 NPs (barium titanate nanoparticles) by simultaneously electrospinning of PVDF NFs and electrospraying of BaTiO3 NPs. Two set of nanogenerator devices were prepared which differ in piezoelectric layer arrangements and volume fraction of piezopolymer and piezoceramic parts. Results showed that, in case of simultaneously electrospinning and electrospraying (E/E), a significant increase in piezoelectric phase content and voltage output has been observed in comparison with the layer by layer arrangement. The improved piezoelctric performace may result from better dipole alignment facilitated by a more intense electric field during the simultaneously E/E process, along with heightened interactions between the two materials arising from enhanced contact in a multilayer configuration. Moreover, the optimum volume ratio of piezopolymer to piezoceramic to obtain the maximum output was 1.5 to 0.5. Therefore, simultaneously E/E effectively enhance the piezoelectric performance without having the common challenges in the electrospinning process of nanocomposites, as well as decreasing the total preparation time and simplifies the processing steps. Having such features, leads to hold great appeal of these nanogenerators for diverse applications. [ABSTRACT FROM AUTHOR]

Properties of pH‐responsive electrospun nanofibers incorporated with biocompatible/degradable Carbopol, commonly used in pharmaceuticals and personal care products, are reported. Sonication of Carbopol dispersions prior to electrospinning leads to uniform incorporation into fibers of the host polymer polyvinylpyrrolidone. The hydration behavior is strongly influenced by pH conditions, forming a viscous network at higher pH. Since Carbopol is more responsive to higher pH, at pH > 6 increasing Carbopol concentration leads to increased uptake volume of buffer solution, faster uptake rate and complete gel formation. The physical spreadability (resulting from a combination of viscoelastic properties and the structural polymer network) of the hydrated fibers is evaluated for multiple Carbopol concentrations and pH conditions. At low starting pH of 4, increasing the Carbopol amount results in slightly increasing viscosity while maintain solution pH. On the other hand, at high starting pH of 8 increasing Carbopol concentrations result in significant reduction in the pH of the buffer solution, which in turn decreases the viscosity of the gel and increases its spreadability. These findings provide guidelines for rational designs of pH responsive Carbopol fibers for various applications, including drug delivery, wound dressing, contraceptive devices, and prevention of sexually transmitted diseases. [ABSTRACT FROM AUTHOR]

In this work polymer nanofibers were functionalized by incorporation of the spin transition (ST) compound [Fe(H2btm)2(H2O)2]Cl2 (FeH2btm) (H2btm=di(1H‐tetrazol‐5‐yl)methane). FeH2btm is an interesting compound due to its ability to reversibly and sensitively switch between high spin (HS) and low spin (LS) state when exposed to common volatile compounds (VOC) like ammonia and methanol. By using polyvinylidene fluoride (PVDF) as the main compound, inhibiting interactions between the complex and polymer were minimized. By using UV‐Vis spectroscopy, the visible and reversible switching between HS and LS state when exposed to an ammonia or hydrochloric acid atmosphere was confirmed. Powder X‐Ray diffraction (PXRD), scanning electron microscopy (SEM) and energy dispersive X‐Ray spectroscopy (EDX) show a homogenous distribution of FeH2btm with no major crystalline accumulations and a mean fiber diameter of 106±20 nm. The composite fiber has a similarly high thermal stability as the pure FeH2btm, as shown by thermogravimetric analysis (TGA). Mössbauer spectroscopy indicates an incomplete spin transition after exposition to ammonia. This could be due to low permeability of the VOC into the composite fiber. [ABSTRACT FROM AUTHOR]

The major challenges of aqueous zinc‐ion batteries (ZIBs) are the dendrite formation and the passivation of zinc metal anode, which restrict their practical applications. Herein, polyacrylonitrile (PAN) and zwitterionic surfactant (Sulfobetaine methacrylate, SBMA) are combined as a precursor to design a modified PAN nanofiber separator by electrospinning. SBMA with sulfonate group [SO3−] can alter the physical property of the precursor solution and electrostatic field during the electrospinning process. Besides, it can regulate the zinc ions crossing and homogenize the electric field by minimizing the zinc ion concentration polarization on the zinc foil surface due to the polar group. As a result, Zn symmetric cells with PAN@SBMA separators show long‐term stability (up to 1700 h), which outdistances the cell with GF‐D (only up to 50 h) under current density at 1 mA cm−2. Meanwhile, the Zn//PAN@SBMA//NH4V4O10 full cells have high specific capacity (236 mAh g−1) and excellent long‐term durability with 84.2% capacity retention after 2000 cycles at 5 A g−1. This work illustrates an easy and effective way to design a high ion transference number and functional PAN‐based separator for regulating Zn2+ deposition for the development of high‐performance ZIBs. [ABSTRACT FROM AUTHOR]

Purpose: Antihyperglycemic drug artemisinin (Art) has recently gained attention as a potential anticancer treatment. In this study, the poly(lactic-co-glycolic acid) (PLGA) polymer was used to create Art-containing nanofibers (NFs) using the electrospinning technique. Methods: The morphological characteristics, rate of degradation, and drug release profile of the NFs were described. In addition, we examined both the cytotoxic effects and internalization of reactive oxygen species (ROS), as well as the expression levels of apoptotic genes following the treatment of SK-BR-3 breast cancer cells with Art and Art-loaded PLGA nanofibers. Results: The bead-free, smooth surface, and randomly aligned electrospun NFs released the medication quickly at first and then steadily for more than 2 weeks. They also showed a rather steady rate of deterioration over the course of 24 days. After 48h, SK-BR-3 cells exposed to ART-loaded NFs shown a substantial cytotoxicity compared to free Art. Additionally, Art-loaded NFs effectively increased intracellular ROS levels, inducing death in cancer cells. Gene expression studies further demonstrated the ability of the produced Art-loaded NFs to significantly modify Bax and Bcl-2 levels as well as activate caspases-3 and P53 compared to free Art. Conclusion: Overall, the results demonstrated the Art-loaded PLGA nanofibers anticancer effectiveness, indicating that it may be employed as an implantable drug delivery system to decrease breast cancer recurrence following surgical resection. [ABSTRACT FROM AUTHOR]

The realization of tunable multicolor luminescence especially full‐spectrum white‐light emission in a single matrix has aroused more attention from researchers. To address the above challenge, Bi3+, and Tb3+ are selected as both activators and sensitizers with the help of energy level matching engineering of Bi3+ and Tb3+ having matching energy levels with Eu3+, a series of 1D Y4Al2O9:Bi3+, Bi3+/Eu3+, Tb3+, Tb3+/Eu3+ and Bi3+/Tb3+/Eu3+ nanofibers (NFs) are designed and synthesized by a simple electrospinning technique combined with an oxidative calcination. Under 298‐nm UV light excitation, Y4Al2O9:Bi3+/Tb3+/Eu3+ NFs demonstrate tunable multicolor luminescence (blue, purple, red, green, yellow, and white) especially full‐spectrum white‐light emission via double energy transfer (ET) effect and modulation of molar ratio among Bi3+, Tb3+ and Eu3+. Additionally, Y4Al2O9:3%Bi3+/7%Tb3+/1%Eu3+ NFs are sensitive to temperature, and the maximum Sα and Sγ values of Y4Al2O9:3%Bi3+/7%Tb3+/1%Eu3+ NFs reach 0.0417 K−1 and 0.84% K−1, respectively. In virtue of electrospinning, triple activators (Bi3+, Tb3+, and Eu3+) are readily and uniformly doped in Y4Al2O9 NFs single matrix to achieve dual function of tunable multicolor luminescence and temperature sensing. The formation principle and luminescence theory of the samples are clarified. The findings in this work are instructive to develop multicolor luminescent phosphors and temperature‐sensing materials. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF) exhibits the great potential to promote proton conduction under low relative humidity for proton exchange membranes (PEMs). In this research, quick and stable proton conduction has been achieved since the prepared COF and polyvinylidene fluoride (PVDF) nanofibers are believed to constitute successive proton conduction channels. The PVDF-COF nanofibers membrane is prepared through the in-situ growth of COF along PVDF nanofibers. The fine compatibility can drive the stable combination of COF with the PVDF nanofibers in PVDF-COF nanofibers. Most importantly, the fibrous PVDF nanofibers accelerate proton conduction through confining the proton conduction pathways. Additionally, ionic liquids of 1-butyl-3-methylimidazolium chloride (BmimCl) and 1-butyl-3-methylimidazole hexafluorophosphate (BmimPF 6) as proton conduction carriers have been introduced to accelerate proton conduction in the prepared PVDF-COF/BmimCl/PA and PVDF-COF/BmimPF 6 /PA membranes. Phosphoric acid (PA) molecules are combined by COF and ionic liquid cations with the formation of intermolecular hydrogen bonds. As a result, the PVDF-COF/BmimPF 6 /PA membrane exhibits the proton conductivity of (1.81 ± 0.07) × 10−1 S/cm at 160 °C. The long-term proton conductivity stability is determined, deriving from the proton conductivities of 1.77×10−2 S/cm at 80 °C and 1.42×10−2 S/cm at 110 °C in the 400 h non-stop measurement. The single fuel cell equipped with the PVDF-COF/BmimPF 6 /PA membrane represents the open circuit voltage of 0.927 V and the peak power density of 178.8 mW/cm2 at 100 °C, 0.907 V and 326.5 mW/cm2 at 120 °C. [Display omitted] • Covalent organic framework is prepared. • COF and ionic liquid synergistically promote proton conduction. • Peak power densities are 178.8 mW/cm2 at 100 °C and 326.5 mW/cm2 at 120 °C. [ABSTRACT FROM AUTHOR]

Sm 0.5 Sr 0.5 CoO 3-δ (SSC) fiber-electrode materials were prepared via electrospinning in this work. The characteristics of SSC fibers are influenced by the parameters of electrospinning, specifically the nitrate concentration of the spinning solution, applied voltage, and the gap between the spinneret and collector. The as-prepared SSC fibers exhibited average diameters ranging from 240 nm to 6.49 μm, which contracted to 50 nm–2.53 μm after calcination at 800 °C. Symmetric cells with SSC fiber-electrodes demonstrated an area-specific resistance (ASR) ranging from 0.212 to 0.508 Ω cm2 at 700 °C in air. In addition to the morphology of SSC fibers, the average grain size of the SSC fibers also exhibited potential influence on their ASR performance. [ABSTRACT FROM AUTHOR]

GdF 3 :Yb3+,Ho3+@void@SiO 2 wire-in-tube structured nanofibers (WITSN) with bifunctional characteristic of up-conversion luminescence and magnetism properties are successfully obtained by self-created technique combining monoaxial electrospinning and single-crucible fluorination technology. The products are pure orthorhombic phase. GdF 3 :Yb3+,Ho3+@void@SiO 2 WITSN exhibit large specific surface area and distinctive void space structure. The unique structure of the prepared nanofibers expands the new field of one-dimensional special morphology nanomaterials. In addition, GdF 3 :Yb3+,Ho3+@void@SiO 2 WITSN have the bifunctionality of excellent up-conversion luminescent and paramagnetic properties. Materials have broad applications prospects in display, lighting, optical imaging, magnetic resonance imaging, and biomedicine. This work presents an innovative and high-efficient approach to construct photoluminescence-magnetism bifunctional GdF 3 :Yb3+,Ho3+@void@SiO 2 WITSN, providing a new idea for the preparation of coated structured nanomaterials with excellent multifunctional characteristics. [Display omitted] [ABSTRACT FROM AUTHOR]

One-dimensional (1D) Y 2 Zr 2 O 7 :Er/Yb tube-in-tube nanostructures were prepared via a simple electrospinning technique with a single nozzle. The diameter of the outer tube of the Y 2 Zr 2 O 7 :Er/Yb tube-in-tube nanostructures is 190–170 nm, the thickness of the outer wall is 22–20 nm, the diameter of the inner tube is 120–100 nm, and the wall thickness of the inner tube is 17–14 nm. The optical properties of the Y 2 Zr 2 O 7 :Er/Yb tube-in-tube nanostructures, including the up-conversion and downshifting luminescence spectra, temperature sensitivity, and thermochromic properties, were studied in detail. Under 980 nm excitation, two weak green emissions at 528 nm and 550 nm, as well as a strong red emission at 650 nm of Er ions, are presented. When excited at 378 nm, the Er ions exhibit strong green emission at 545 nm, two weak red emission peaks at 650 and 680 nm, and near-infrared emission peaks at 1400–1600 nm. With increasing environmental temperature, the luminescence color of the 1D Y 2 Zr 2 O 7 :Er/Yb tube-in-tube nanostructures exhibited a transition from "orange→yellow→ green" when excited at 980 nm. For the 1D Y 2 Zr 2 O 7 :xEr/yYb tube-in-tube nanostructures (x = 0.01, 0.02, 0.03; y = 0.05, 0.10, 0.15), the maximum values of S r are 2.3 % K−1 under 980 nm excitation and 2.1%K−1 under 378 nm excitation within the temperature range of 303–723 K. This work develops integrated multifunctional optical materials and provides an alternative approach for the fabrication of nanoscale smart platforms, advanced displays, and applications in information security. [ABSTRACT FROM AUTHOR]

In order to clarify the effect of feeding rate ratio (Rsr) for polylactic acid (PLA) to polyethylene glycol (PEG) on the performance of thermal regulation nanofibers, PLA and PEG solutions were used as the outer and inner spinning solutions, respectively, to develop PLA/PEG nanofibers (NFp‐p) through coaxial electrospinning. NFp‐p nanofibers with Rsr of 2:1, 3:1, and 4:1 were labeled PR1, PR2, and PR3, respectively. The morphology, chemical structure, mechanical properties, and thermal performance of NFp‐p were tested, and the thermal regulation function was investigated. The results showed that increasing Rsr could increase the diameter of NFp‐p, with PR1 having the smallest average diameter (520 nm). PR1 had the lowest water contact angle (122.4°), and higher Rsr enhanced the encapsulation effect of PLA on PEG. The mechanical properties of NFp‐p were significantly improved compared to pure PLA, with PR1 and PR3 exhibiting the highest breaking stress (2.5 MPa) and breaking strain (213%). The thermal performance of NFp‐p could be regulated by Rsr, with PR1 showing a more pronounced endothermic peak due to the melting of PEG, and the highest phase‐change enthalpy (13.2 J/g). Lower Rsr enhanced the thermal regulation function of NFp‐p, and PR1 showed superior thermal regulation performance. [ABSTRACT FROM AUTHOR]

Bioscaffolds with characteristics of the tumor microenvironment is an important substrate to support the formation of multicellular tumor spheroids (MCTS). Conventional biomaterials promote MCTS formation using tumor extracellular matrix (ECM) components and exogenous growth factors, but lack individualized tumor cell niche construction which may restricts cell biology and drug discovery research. Herein, an ECM mimicked fiber composite dual-network hydrogel (FCDNG) was constructed. The 3D nanofibrous framework was introduced into the hydrogel by a "dispersion-swelling" method and an alginate/platelet-rich plasma (PRP) dual-network hydrogel was constructed by a simple "one-step" activation process. The scaffold can well control the physicochemical conditions that mimic the ECM structure and biomimetic mechanical properties. The fibrin formed by PRP can promote tumor cell proliferation, angiogenesis and cancer stem cell enrichment. Meanwhile, FCDNG has suitable degradation properties to meet the matrix remodeling requirements during the formation of MCTS. Tumor cells cultured in FCDNG had enhanced tumor stemness, proliferation, and resistance to chemotherapeutic agents, and thus providing an effective strategy for clinical drug evaluation. [ABSTRACT FROM AUTHOR]

Electrospinning technology has demonstrated extensive applications in biomedical engineering, energy storage, and environmental remediation. However, its utilization in the cosmetic industry remains relatively underexplored. To address the challenges associated with skin damage caused by preservatives and thickeners used for extending the shelf life of conventional products, a soothing lavender-scented electrospun fibrous eye mask with coaxial layers was developed using the electrospinning technique. Polyvinyl alcohol (PVA) served as the hydrophilic outer sheath, while polycaprolactone (PCL) constituted the hydrophobic core, with lavender oil (LO) encapsulated within. The structural and physicochemical properties of the samples were characterized using a scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and contact angle measurements. Upon hydration, the fibrous membrane exhibited strong adhesion properties, notable antioxidant activity, and a degree of antibacterial efficacy, demonstrating its potential for safe and effective use in skincare and eye mask applications. These findings suggest that the developed electrospun material offers promising functional properties and functional properties for integration into cosmetic formulations. [ABSTRACT FROM AUTHOR]

The high accumulation of plastic waste in the environment has led to great interest in biodegradable polymers, such as polylactic acid (PLA) or polyhydroxyalkanoates (PHAs). Their benefits, combined with the application of electrospinning technology, represent an innovative proposal for the food packaging industry. This article provides a comprehensive review of the latest developments of PLA- and PHA-biopolyester-based electrospun materials for food packaging applications, summarizing the reported technologies, material properties, applications, and invention patents. In addition, the legislation used to assess their biodegradability is also detailed. Electrospun packaging materials are largely developed through uniaxial, coaxial, emulsion, multiaxial, and needleless techniques. PLA- and PHA-biopolyester-based electrospun materials can be obtained as single and multilayer packaging structures, and the incorporation of natural extracts, organic compounds, and nanoparticles has become a great strategy for designing active food packaging systems. The biodegradability of electrospun materials has mainly been evaluated in soil, compost, and aquatic systems through ASTM and ISO normatives. In this review, the dependence of the biodegradation process on the polymer type, conditions, and test methods is clearly reviewed. Moreover, these biodegradable electrospun materials have shown excellent antioxidant and antimicrobial properties, resulting in a great method for extending the shelf life of fruits, bread, fish, and meat products. [ABSTRACT FROM AUTHOR]

High-performance and cost-efficient electrocatalysts and electrodes are needed to improve the hydrogen evolution reaction (HER) for the hydrogen (H2) generation in electrolysers, including microbial electrolysis cells (MECs). In this study, free-standing carbon nanofiber (CNF) films with supported cobalt phosphide nanoparticles have been prepared by means of an up-scalable electrospinning process followed by a thermal treatment under controlled conditions. The produced cobalt phosphide-supported CNF films show to be nanoporous (pore volume up to 0.33 cm3 g−1) with a high surface area (up to 502 m2 g−1) and with a suitable catalyst mass loading (up to 0.49 mg cm−2). Values of overpotential less than 140 mV at 10 mA cm−2 have been reached for the HER in alkaline media (1 M KOH), which demonstrates a high activity. The high electrical conductivity together with the mechanical stability of the free-standing CNF films allowed their direct use as cathodes in a MEC reactor, resulting in an exceptionally low voltage operation (0.75 V) with a current density demand of 5.4 A m−2. This enabled the production of H2 with an energy consumption below 30 kWh kg−1 H2, which is highly efficient. [ABSTRACT FROM AUTHOR]

This work is devoted to the creation of biocompatible fibrous materials with a high antimicrobial effect based on poly-3-hydroxybutyrate (PHB) and chlorophyll (Chl). The data obtained show the possibility of obtaining fibrous materials from PHB and Chl by electrospinning methods. The obtained electrospun matrices were investigated by the SEM, DSC and FTIR methods. Various key properties of the matrices were evaluated, including hydrophilicity and mechanical strength, as well as photodynamic and light-dependent antimicrobial effects against the conditionally pathogenic microorganism Staphylococcus aureus. The results demonstrate a significant improvement in electrospinning properties for a concentration of 0.5% Chl and a reduction in fiber formation defects, as well as an increase in the strength of nonwovens. It was found that the antimicrobial potential of Chl-PHB (with concentrations of Chl of 1.25 and 1.5%) is higher than that of Chl in free form. It was also determined that irradiation increases the inhibitory effect of Chl, both in free form and in the form of a complex with a polymer. [ABSTRACT FROM AUTHOR]

Hydrogen is regarded as an ideal energy carrier to cope with the energy crisis and environmental problems due to its high energy density, cleanliness, and renewability. Although there are several primary methods of industrial hydrogen production, hydrogen evolution reaction (HER) is an efficient, eco-friendly, and sustainably green method for the preparation of hydrogen which has attracted considerable attention. However, this technique is characterized by slow reaction kinetics and high energy potential owing to lack of electrocatalysts with cost-effective and high performance which impedes its scale-up. To address this issue, various studies have focused on electrospun micro/nanofiber-based electrocatalysts for HER due to their excellent electron and mass transport, high specific surface area, as well as high porosity and flexibility. To further advance their development, recent progress of highly efficient HER electrospun electrocatalysts is reviewed. Initially, the characteristics of potential high-performance electrocatalysts for HER are elucidated. Subsequently, the advantages of utilizing electrospinning technology for the preparation of electrocatalysts are summarized. Then, the classification of electrospun micro/nanofiber-based electrocatalysts for HER are analyzed, including metal-based electrospun electrocatalyst (noble metals and alloys, transition metals, and alloys), metal–non-metal electrocatalysts (metal sulfide-based electrocatalysts, metal oxide-based electrocatalysts, metal phosphide-based electrocatalysts, metal nitride-based electrocatalysts, and metal carbide-based electrocatalysts), metal-free electrospun micro/nanofiber-based electrocatalysts, and hybrid electrospun micro/nanofiber-based electrocatalysts. Following this, enhancement strategies for electrospun micro/nanofiber-based electrocatalysts are discussed. Finally, current challenges and the future research directions of electrospun micro/nanofiber-based electrocatalysts for HER are concluded. [ABSTRACT FROM AUTHOR]

In electrospinning, nanofibers are frequently produced in nonwoven web form. Their poor mechanical properties (below 100 MPa) and difficulty in tailoring the fibrous structure have restricted their applications. However, advanced materials must be highly resistant to both deformation and fracture. By combining electrospinning technology with stretching, we have overcome this disadvantage and demonstrated a polyacrylonitrile nanofiber yarn with a tensile strength of 743 ± 20 MPa. The nearly perfect uniaxial orientation of the fibrils under the stretching process is crucial for the remarkable mechanical properties of the yarn. Additionally, the nanofiber yarn was functionalized by a dip-coating process with silver nanowires (AgNWs), imparting conductive properties. This conductive, high-strength nanofiber yarn demonstrates practical applications in flexible and wearable devices. The presented strategy is versatile and can be adapted to create other high-performance nanofiber yarns, with potential uses in fields such as biomedicine and smart textiles. [ABSTRACT FROM AUTHOR]

In this study, modification of regular masks using composite nanofibers containing porous nanostructures has been considered in order to increase their efficiency in dealing with new threats. For this purpose, polystyrene was used as a low-cost polymer to prepare nanofibers and modify the surface of the respirator mask. ZIF-8 nanostructures with different sizes (14, 23, 65,144, and 265 nm) and zinc oxide nanoparticles, with an approximate size of 36 nm, were added to polymer nanofibers.2-methyl imidazole and Zn(NO3)2 were used to synthesize nanostructures. Two different methods (injection and stabilization) were used to incorporate nanostructures into fibers. The percentage of ZIF-8 and ZnO nanostructures were 0.5 and 2 wt% respects to polystyrene, respectively. Synthesis reactions and preparation of fibrous filters were carried out at ambient temperature. FESEM, FTIR, EDAX, TGA, and XRD techniques were used to identify the prepared nanoparticles and fibers. To evaluate the performance of the modified filters, their efficiency in removing suspended particles below 2.5 microns as well as CO2, SO2 and NO2 gases was surveyed. The results showed that ZIF nanoparticles with arbitrary sizes have been synthesized and successfully stabilized on the surface of nanofibers. Modifying the surface of the commercial mask by electrospinning method resulted in forming a fibrous layer with an approximate diameter of 700 nm and the presence of stabilized nanostructures in both methods was confirmed using FESEM images. Adding the nanofibers to the surface of the filter significantly increased their efficiency in removing suspended particles and toxic gases. The optimized modified filter contained ZIF-8 with14nm dimension and could remove sub-micron particles, CO2, NO2, and SO2 gases by 99, 91, 87, and 86%, respectively, making it as effective as commercially available N-95 masks. Moreover, it was observed that the incorporation of nanostructures by the stabilization method was more effective in improving the filtering efficiency of the fibrous mask. [ABSTRACT FROM AUTHOR]

Yolk-shell SnO2 mesoporous double-layer nanotubes were synthesized in one-step by single nozzle electrospinning. Compared with the traditional electrospinning using polyvinylpyrrolidone (PVP) as the precursor polymer to obtain the single nanotube material, two PVPs (PVPK88-96 and PVPK23-27) with different molecular weights in solution coupled with Sn2+ easily form the core-shell structure nanofiber through phase separation. The yolk-shell double-layer SnO2 nanotubes were obtained after calcination at 600 °C for 2 h. The yolk-shell SnO2 mesoporous double-layer nanotube is a promising sensing material toward 3-hydroxy-2-butanone as it shows high sensitivity, cycling stability, and selectivity. Moreover, the response and recovery times of the yolk-shell SnO2 mesoporous double-layer nanotubes toward 1 ppm 3-hydroxy-2-butanone were 122 s and 117 s. [ABSTRACT FROM AUTHOR]