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The microstructure plays a crucial role in the manufacturing and application of polyacrylonitrile fibers, which serve as precursors for carbon fibers. Synchrotron radiation small angle x-ray scattering (SR-SAXS) is a non-destructive and precise technique for analyzing fiber structures. This study employed one-dimensional SR-SAXS mapping to extract key structural parameters such as periodicity, lamellae thickness, and the extent of amorphous regions, as well as the directional orientation in γ-irradiated, pre-oxidized polyacrylonitrile fibers. The analysis revealed a three-layered structure comprising a surface skin, a transitional layer, and a central core. Notably, the lamellar thickness exhibits a "U"-shaped distribution, while the long-period structures, amorphous regions, and orientational properties demonstrate a "wave-like" pattern. Within this structure, the skin exhibits a higher level of orientation, with the orientation decreasing progressively from the skin toward the core layer. The structure of the layered crystal was further corroborated by the morphological analysis. In addition, molecular simulations were performed to propose the mechanisms underlying the formation of this layered structure. This comprehensive investigation using SR-SAXS and one-dimensional mapping provides detailed insights into the microstructural and morphological characteristics of polyacrylonitrile fibers, which can inform future advancements in material processing and refinement techniques for the production of advanced fibers. [ABSTRACT FROM AUTHOR]

Currently, the problem of air pollution is getting more and more serious, especially the pollution of tiny solid particles (PM, particulate matter) in the air, which poses a great challenge to the environment and human health. Therefore, it is particularly important to develop air filtration materials with high filtration efficiency and low resistance to meet this challenge. In this study, we propose to prepare air filtration membranes by centrifugal jet electrospinning technology, design multifactorial orthogonal coupling experiments, and investigate the effects of key process parameters of centrifugal jet electrostatic spinning, including solution concentration, airflow rate, rotational speed, and voltage, on the fiber diameter and uniformity by applying the polar analysis of variance and analysis of variance. PAN‐BaTiO3 electret nanofiber filtration membranes with high efficiency and low resistance were prepared by combining the optimized process of centrifugal blowing electrospinning. Various characterization methods (tensile test, water contact angle test, surface charge test, filtration test) were used to evaluate the effect of different BaTiO3 electret contents (0%, 0.1%, 0.5%, 1%) on the comprehensive performance of the filtration membranes, and the electret filtration efficiency of the electret filtration membranes prepared by the present process reached as high as 96.56% with a pressure drop of 29 Pa. [ABSTRACT FROM AUTHOR]

This report demonstrates the development of carbon fibers (CFs) decorated with TiO2 nanoparticles (NPs) as an efficient photocatalyst for the photocatalytic degradation of methylene blue (MB) as a model dye. Carbon fibers were produced by carbonization of polyacrylonitrile fibers, previously produced by centrifugal spinning. Subsequently, the CFs were decorated with TiO2 NPs (CFs@TiO2) by tailored soaking protocol using aqueous TiCl4 solution with different concentrations (0.025, 0.05, 0.1, and 0.2 M). SEM analyses revealed that soaking in TiCl4 produced a smooth, conformal, continuous TiO2 nanoparticulate coating with thickness increasing from 40.4 ± 21.2 to 257.9 ± 63.9 nm with increasing TiCl4 concentration. X-ray diffraction and Raman spectroscopy confirmed the anatase nature of TiO2. Photocatalytic decomposition rates of MB were assessed under UV light illumination for all CFs@TiO2 samples, and it was revealed that the lowest amount of TiO2 NP on C yielded the highest rates. The synergistic interaction between CFs and TiO2 NPs with a uniform morphology and a well-crystalline anatase structure, present in an optimal amount of fiber bodies, is the key reason for the remarkable photocatalytic performance. This work shows that C fibers decorated with an optimal amount of TiO2 NPs have a great potential as an effective photocatalytic material. [ABSTRACT FROM AUTHOR]

Chemoselective reduction of nitroarenes to corresponding arylamines is a significant reaction in the chemical industry. However, in the presence of other reducible groups, including halogenated nitrobenzene, nitrobiphenyl, and nitroquinoline in the same molecule of nitroaromatics, the control of chemoselectivity remains challenging. Here, a facile fabrication of a heterogeneous iron‐based catalyst is reported as a potential alternative to precious metal catalysts for the chemoselective reduction of nitroarenes. The pyrolysis of iron acetate/polyacrylonitrile (PAN) template under an inert atmosphere furnishes active Fe3O4 nanoparticles (NPs) encapsulated in nitrogen‐doped (N‐doped) carbon layers, which can provide more catalytic active sites (Fe3O4/PAN@800). Notably, non‐precious iron oxide NPs supported on N‐doped carbon support prevent aggregation, thereby enhancing the catalytic activity. The sustainable and reusable Fe3O4/PAN@800 catalyst, having only 0.8% metal content as demonstrated by x‐ray photoelectron spectroscopy, delivers excellent yields of corresponding amines from differently functionalized nitroarenes. Hydrogenation of a series of structurally functionalized nitroarenes produced excellent yields of anilines, which serve as building blocks and intermediates for fine and bulk chemicals. Hydrogenation of 2‐chloro‐3‐nitropyridine, 2‐nitro‐1,1′‐biphenyl, ortho‐nitroaniline, and 4‐aminophenyl acrylonitrile yielded respective anilines up to 99%. The active sites of Fe3O4 have magnetic performance, hence, the catalyst can be easily recovered using a magnet and reused for at least five cycles without significant loss of catalytic activity. Therefore, the easily prepared, cost‐effective, and reusable Fe3O4/PAN@800 catalyst presented in this study shows potential for applications in the selective reduction of aromatic nitro compounds. Consequently, this study potentially establishes a guideline for the facile preparation of abundant transition‐non‐noble metal‐based reusable supported catalysts for various applications in the chemical industry. [ABSTRACT FROM AUTHOR]

The content of peroxide in acrylonitrile is critical for the production of polyacrylonitrile‐based carbon fibers. Peroxide‐free acrylonitrile is used as a blank solution for testing the peroxide content of acrylonitrile, which storage conditions are important to the test. Of course, for the change of peroxide content in acrylonitrile stored for a period of time has an effect on the production of carbon fiber. In order to study the effect of storage conditions on peroxide in peroxide‐free acrylonitrile and acrylonitrile, the changes at refrigerator and room temperature were studied, respectively. Studies have shown that storage at temperatures below 20 °C for 3 months hardly affect the use of either peroxide‐free acrylonitrile or acrylonitrile. The experimental results obtained are useful for practical production and testing, which can improve the accuracy of testing and stability of production. [ABSTRACT FROM AUTHOR]

Sulfurized polyacrylonitrile (SPAN) cathodes in high energy‐density Li‐metal batteries have garnered widespread interest owing to their good cycling stability and moderately high capacities. However, their application is hindered by the low prevalence of advanced electrolytes that can simultaneously mitigate polysulfide generation at the cathode and stabilize the Li‐metal anode. Here, a weakly solvating electrolyte is presented, employing a single solvent tetrahydropyran (THP). The solvation structure is effectively tuned by adjusting the salt concentration to stabilize both the Li‐metal anode and SPAN cathode. This approach enables stable cycling with high SPAN loadings (≈5 mg cm−2) and lean electrolyte contents (≈5 µL mgSPAN−1) across a wide temperature range: 0 °C, room temperature, and 50 °C. A pouch cell with a high SPAN loading and a low electrolyte‐to‐SPAN (E/SPAN) ratio of 3 µL mg−1 shows a stable 79.1% capacity retention after 40 cycles. Additionally, THP can be effectively employed in localized high‐concentration electrolyte (LHCE) systems to reduce the diluent‐to‐solvent ratio for greater LHCE viability. The study demonstrates the potential of weakly solvating solvents in Li‐SPAN batteries, offering a pathway for their practical application. [ABSTRACT FROM AUTHOR]

A membrane with a low methanol permeability and high proton conductivity (σ p) is essential for the effective operation of a direct methanol-based fuel cell. Herein, a bio-metal organic framework was prepared with natural α-amino acids as ligands and then combined with hydrolyzed polyacrylonitrile (PAN) nanofibers (AA-MOF@PAN). The resulting nanocomposite membranes were subsequently integrated into a Nafion matrix (AA-MOF@PAN/Nafion). The –NH 2 groups on AA-MOF@PAN interact with –SO 3 H groups on Nafion, forming long-range acid-base pairs along the interface between the matrix and nanofibers. This interaction creates abundant proton-conducting sites for proton exchange membrane. Notably, the AA-MOF@PAN-4h/Nafion membrane demonstrated an exceptional proton conductivity (σ p) of 0.25 S cm−1 and a higher power density of 117.61 mW cm−2 compared to the recast Nafion membrane. This study offers valuable insights into the three-dimensional ordered design of a natural α-amino acids as a proton transfer sites and highlighting their potential applications in proton exchange membranes. • In situ growth of uniformly distributed AA-MOF onto hydrolyzed PAN nanofiber. • AA-MOF@PAN were introduced as proton-conducting channels. • AA-MOF@PAN-4h/Nafion exhibited the highest proton conductivity of 0.25 S cm−1 at 80 °C. • Introduction of AA-MOF@PAN resulted in a reduced fuel crossover. [ABSTRACT FROM AUTHOR]

The effect of cyclization degree of nitrogen thermal pretreatment on the radial structure difference of polyacrylonitrile(PAN) oxide fibers is explored. In this paper, PAN fibers were isothermally heated in nitrogen at 170°C, 190°C and 210°C for 0, 10, 20, 30, 40, and 50 min, respectively, so as to obtain pre‐treated fibers with cyclization degrees of 0%, 19.96%, 35.18%, 38.92%, 42.80%, and 53.12%, respectively. The pre‐treated fibers were further stabilized in an oxygen atmosphere. The scanning results show that the radial structure difference of oxide fibers first decreases and then increases with cyclization degree increasing. Through FTIR, SEM and Raman characterization, it is found that this phenomenon is mainly related to the influence of nitrogen thermal pretreatment on oxygen diffusion. Therefore, to improve the thermal stability efficiency of PAN fibers by means of nitrogen thermal pre‐treatment, it is necessary to control the degree of cyclisation, and the appropriate degree of cyclisation in the present work is about 35%. [ABSTRACT FROM AUTHOR]

Dopamine (DA) is a widely present, calcium cholinergic neurotransmitter in the body, playing important roles in the central nervous system and cardiovascular system. Developing fast and sensitive DA detection methods is of great significance. Fluorescence-based methods have attracted much attention due to their advantages of easy operation, a fast response speed, and high sensitivity. This study prepared hydrophilic and high-performance CdS/ZnS quantum dots (QDs) for DA detection. The waterborne CdS/ZnS QDs were synthesized in one step using the amphiphilic polymer PEI-g-C14, obtained by grafting tetradecane (C14) to polyethyleneimine (PEI), as a template. The polyacrylonitrile nanofiber membrane (PAN-NFM) was prepared by electrospinning (e-spinning), and a metal organic frame (ZIF-8) was deposited in situ on the surface of the PAN-NFM. The CdS/ZnS QDs were loaded onto this substrate (ZIF-8@PAN-NFM). The results showed that after the deposition of ZIF-8, the water contact angle of the hydrophobic PAN-NFM decreased to within 40°. The nanofiber membrane loaded with QDs also exhibited significant changes in fluorescence in the presence of DA at different concentrations, which could be applied as a fast detection method of DA with high sensitivity. Meanwhile, the fluorescence on this PAN-NFM could be visually observed as it transitioned from a blue-green color to colorless, making it suitable for the real-time detection of DA. [ABSTRACT FROM AUTHOR]

In the present work, a novel 'doped ceramic-polymer composite'-based solid polymer electrolytes (SPEs) has been synthesized using Zr (LAZTP) and Nb (LANbTP)-doped LATP as a ceramic filler and polyacrylonitrile (PAN) as a host polymer via the solution cast method. A series of SPEs with different ceramic loadings ranging from 10, 20, 30, 40, and 80 wt. % have been investigated using XRD, SEM, and impedance analysis. XRD spectra show the presence of crystalline ceramic peaks in composite solid polymer electrolyte. Further, the homogeneous distribution of the filler has been confirmed by SEM images. For SPEs, the highest conductivity of 5.31 × 10−5 S cm−1 has been obtained for PAN + LANbTP30 at room temperature. Whereas, the optimized conductivity for LATP-incorporated PAN shows 1.79 × 10−5 S cm−1, and the LAZTP-incorporated sample shows a conductivity of 3.03 × 10−5 S cm−1 at room temperature. Also, LANbTP-contained SPE shows excellent voltage stability of 4.90 V w.r.t. pure PAN. [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]

The purpose of this research is to solve the problem of debonding of polyacrylonitrile (PAN) fibers in asphalt to improve the property of asphalt materials. A simple layer-by-layer self-assembly method was employed, in which a chitosan (CS)/phytanic acid (PA) coating was first constructed on the fiber surface. This coating immobilized Fe3O4 nanoparticles on the fiber surface by electrostatic adsorption and coordination, resulting in a robust active surface to obtain Fe3O4-PA-CS-PAN fibers, which were used to laminate styrene–butadiene–styrene (SBS)-modified asphalt. Dynamic shear rheometer (DSR) tests confirmed that the Fe3O4-PA-CS-PAN fiber-modified asphalt possessed superior viscoelastic properties and rutting resistance. At 64 °C, the viscosity modulus (G′) and viscous modulus (G′′) of the 1.5% Fe3O4-PA-CS-PAN fiber-modified asphalt increased by 18.23% and 26.19%, respectively, compared with that of the same dosage of PAN fiber-modified asphalt. This can be ascribed to the effective enhancement of the bonding of the interface between the modified PAN fibers and the asphalt. This research contributes to the development and improvement of future road materials. [ABSTRACT FROM AUTHOR]

The production of high-performance carbon fibers relies heavily on the structural transformations of polyacrylonitrile (PAN) fiber during processing. In this article differential scanning calorimetry (DSC), synchrotron small-angle X-ray scattering (SAXS), and synchrotron wide-angle X-ray diffraction (WAXD) were used to study the changes of the thermal properties, voids and crystal structure of the PAN precursor fibers on industrial lines during the continuous processing stages, i.e., after the treatment in the coagulation bath, after stretching in boiling water and after stretching in high-temperature steam. The findings of this study suggest that after boiling water stretching the molecular chain motion of the PAN precursor fiber weaken, resulting in the expansion of the voids. After high-temperature steam stretching the voids became elliptical and oriented in the stretching direction. Although the boiling water stretching process partially damaged the (100) crystal planes of the PAN precursor fibers, it does not hinder their overall crystalline structure. The high stretching ratio primarily affected the orientation of the molecular chains. This orientation, even in the context of partial crystal plane disruption, further promoted the crystallization of the (100) crystal planes in the fibers. These experiments explored the correlation between the processing technology and fiber structure transformation of PAN-based carbon fibers, resulting in producing a guide for the preparation of high-performance carbon fibers with fewer defects. [ABSTRACT FROM AUTHOR]

PAN fibers are characterized by having a large surface-to-volume ratio and small pores, which are beneficial for applications in filtration and specific molecular detection systems. Naturally, larger items are filtered, and a lower ratio between specific and nonspecific binding is expected since small pores do not allow larger elements to penetrate through membranes; thus, nonspecific binding is enhanced. We prepared and tested fiber membranes (diameter cca 700 nm) functionalized with a specific antibody to prove that even microscopic systems such as bacteria could be specifically identified. In addition, we established a methodology that enabled the effective binding of bacteria in not only an aqueous environment but also air. Our data clearly prove that even large systems such as bacteria could be specifically identified by fiber membranes surface-functionalized with a specific antibody. This research opens the door to the construction of biosensors for the fast, inexpensive, and sensitive identification of airborne bacterial contaminants and other airborne pollutants. [ABSTRACT FROM AUTHOR]

We present a mesoscale model and the simulation results of a system composed of polyacrylonitrile (PAN), carbon nanotubes (CNTs), and a mixed solvent of dimethylsulfoxide (DMSO) and water. The model describes a fragment of a nascent PAN/CNT composite fiber during coagulation. This process represents one of the stages in the production of PAN composite fibers, which are considered as precursors for carbon fibers with improved properties. All calculations are based on dynamic density functional theory. The results obtained show that the greatest structural heterogeneity of the system is observed when water dominates in the composition of the mixed solvent, which is identified with the conditions of a non-solvent coagulation bath. The model also predicts that the introduction of CNTs can lead to an increase in structural heterogeneity in the polymer matrix with increasing water content in the system. In addition, it is shown that the presence of a surface modifier on the CNT surface, which increases the affinity of the filler to the polymer, can sufficiently reduce the inhomogeneity of the nascent fiber structure. [ABSTRACT FROM AUTHOR]

In this study, novel polymer nanocomposite films based on polyvinylidene fluoride/polyacrylonitrile/zirconium dioxide (PVDF/PAN/ZrO2) were prepared using a solution casting technique. The structural modifications and morphological properties were analyzed by x‐ray diffraction (XRD) and high resolution scanning electron microscopy (HRSEM). The obtained results verified the filler‐polymer interactions and uniform dispersion of the ZrO2 filler in the host polymers (PVDF and PAN). Thermal stability of up to 46% leftover residue for 30% ZrO2 nano‐filler loading in the blend polymer nanocomposite was analyzed by thermogravimetric analysis (TGA). The dielectric properties such as dielectric constant and dielectric loss values and impedance, Q‐factor, and AC conductivity were analyzed using an impedance analyzer. The decrement in impedance with increasing nano‐filler content with improved dielectric, thermal, Q‐factor, energy density and conductivity properties signifies the prepared novel PVDF/PAN/ZrO2 polymer nanocomposite as an effective material for flexible electronics applications. [ABSTRACT FROM AUTHOR]

Adsorptive nanofiber electrospun membranes (ANEMs) show promise for heavy metal removal, particularly in dilute solutions. Nanofibrous polyacrylonitrile (PAN) membranes incorporating Cloisite 20A (C20) organoclay were fabricated via electrospinning for As(V) removal. The impact of C20 on structural properties and As(V) removal efficiency of the nanofiber membranes was investigated. The results indicated that the PAN‐C20 membranes morphology was uniform, with fiber diameters mostly falling within the 100–300 nm range. Incorporation of C20, especially in an exfoliated structure, led to increased hydrophilicity, mechanical strength, and roughness of the membranes. Batch adsorption results revealed that the adding C20 up to 1.5 wt.% significantly enhanced adsorption capacity due to the higher concentration and proper C20 dispersion. Dynamic filtration showed that the PAN‐C20(1.0) membrane achieved over 90% As(V) removal efficiency for 960 min and demonstrated excellent regeneration ability. Highlights: Cloisite 20A organoclay was incorporated into PAN by electrospinning to prepare adsorptive membrane.Adsorptive membranes were used for As(V) removal from water.Type of Cloisite 20A dispersion in PAN in dynamic filtration was more important than in static adsorptionPAN‐C20‐1.0 with exfoliated structure showed higher removal efficiency than PAN‐C20‐1.0 with intercalated structure.PAN‐C20‐1.0 membrane was usable for multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are gaining tremendous attention as promising energy storage solutions due to their impressive energy density and the affordability of sulfur. However, the practical use of Li–S batteries encounter major obstacles such as the polysulfide shuttle effect, which leads to capacity loss and decreased cycling stability. Herein, a polyethylene imidazole/polyacrylonitrile (PVIMPAN) nanofibers‐modified Celgard separator is constructed via a facile electrospinning strategy and used as a polysulfides barrier for Li–S batteries. The electron‐deficient imidazole groups introduced on the surface of PVIMPAN separators create a barrier that prevents polysulfide shuttling and extends cycle life. Additionally, the developed PVIMPAN separator exhibits a significantly enhanced Li+ transfer number of 0.60, compared to the commercial Celgard separator (0.20). This enhancement can be attributed to the strong binding energy between imidazole groups and bis(trifluoromethanesulphonyl)imide anion, leading to improved Li plating and stripping performance. Consequently, incorporating the PVIMPAN separator into Li–S batteries enable the achievement of a discharge capacity of 786.0 mAh g−1 with close to 100% Coulombic efficiency after 500 cycles at 1C (25 °C). It is believed that this work can provide valuable insights for designing suitable and robust separators for metal–sulfur batteries. [ABSTRACT FROM AUTHOR]

The plastic deformation of the microfibrils governs the formation and development of orientation, crystallization, and structural defects in polyacrylonitrile (PAN) fibers due to the flow‐fiber coupling effect during stretching process. In this study, we investigated the morphological changes of microfibrils in PAN fibers during wet‐fiber stretching using ultrathin section technology and electron microscopy observation. Their plastic deformation mechanism was also revealed. An interconnected network was formed and separated by the pore/voids during coagulation process. Stretching forces facilitated the plastic deformation of microfibrils, resulted in their elongation and orientation. Moreover, the inter‐fibril distance reduced and pore/void shape and dimensions were changed. The distinct response of microfibril elements under stretching force resulted in skin‐core structures within the fiber. Tensile strength increased from 27 to 382 MPa, while elongation at break decreased from 225% to 28%. Aligned microfibrils exhibited high tensile strength, whereas unoriented microfibrillar networks showed relatively high elongation properties. Additionally, we proposed a relationship between microfibril morphology changes and fiber mechanical properties. [ABSTRACT FROM AUTHOR]

Cement is known to be brittle and usually reinforced with fibers. However, there is a lack of effective chemical bonding between organic fibers and inorganic cement, resulting in a weaker interfacial bonding strength. In this paper, amino hyperbranched polymer (HBP) was used to modify the surface of polyacrylonitrile (PAN) fibers, and then silica nanoparticles (SiO2 NPs) were grafted on the surface of modified PAN fibers to realize the inorganic treatment of organic fibers. The modified PAN fibers applied to cement concrete can significantly enhance the interfacial strength between the fibers and cement. The morphology and chemical composition of the modified PAN fibers were characterized by scanning electron microscope, atomic force microscope, electron energy dispersive spectroscopy, and Fourier transform infrared spectroscopy, and the influence of grafting conditions on grafting effect was analyzed. The results show that SiO2 NPs were evenly distributed on the surface of PAN fiber. When SiO2 NPs concentration was 4%, grafting temperature was 50°C, and grafting time was 4 h, the grafting degree of SiO2 NPs grafted PAN fiber can reach to 1.4%. After coating with SiO2 NPs, the pullout bonding strength of the PAN fiber was increased from 5.5 to 6.5 cN. [ABSTRACT FROM AUTHOR]

Herein, we present a novel method for fabricating a triboelectric nanogenerator using Polyacrylonitrile (PAN) on both sides as triboelectric pairs, incorporating metal‐organic frameworks (MOFs) such as ZIF‐8, ZIF‐67, MIL‐100, and HKUST‐1 during the electrospinning process. The triboelectric properties of the MOF‐incorporated fibers are thus tailored and positioned within the triboelectric series for the first time. The resulting triboelectric polarity of the composite fiber is linked to the optical bandgap energy of the PAN and the MOF/PAN composite, facilitating electron transfer between materials of different work functions and leading to enhanced output in the developed triboelectric devices. Fascinatingly, the appropriate choice of MOF filler also displayed the potential for reversing the triboelectric polarity of PAN nanofiber. Consequently, incorporating ZIF‐8 and MIL‐100 into PAN nanofibers led notably to contrasting trends in triboelectric polarity, with the pair generating an open‐circuit output voltage of 100 V, short‐circuit current of 1.35 μA, and a power density of 18.4 mW/m2 respectively. The fabricated device demonstrated effectiveness for mechanical energy harvesting applications and also as a self‐powered humidity sensor, displaying rapid response to changes in ambient humidity levels with a maximum sensitivity of 2.14 V/%RH, for relative humidity range between 50 and 90% during the humidifying cycle. [ABSTRACT FROM AUTHOR]

Catalytic performance decline is a general issue when shaping fine powder into macroscale catalysts (e.g., beads, fiber, pellets). To address this challenge, a phenolic resin-assisted strategy was proposed to prepare porous Co/N carbon beads (ZACBs) at millimeter scale via the phase inversion method followed by confined pyrolysis. Specially, p-aminophenol–formaldehyde (AF) resin-coated zeolitic imidazolate framework (ZIF-67) nanoparticles were introduced to polyacrylonitrile (PAN) solution before pyrolysis. The thermosetting of the coated AF improved the interface compatibility between the ZIF-67 and PAN matrix, inhibiting the shrinkage of ZIF-67 particles, thus significantly improving the void structure of ZIF-67 and the dispersion of active species. The obtained ZACBs exhibited a 99.9% removal rate of tetracycline (TC) within 120 min, with a rate constant of 0.069 min−1 (2.3 times of ZIF-67/PAN carbon beads). The quenching experiments and electron paramagnetic resonance (EPR) tests showed that radicals dominated the reaction. This work provides new insight into the fabrication of high-performance MOF catalysts with outstanding recycling properties, which may promote the use of MOF powder in more practical applications. [ABSTRACT FROM AUTHOR]

Rare-earth metallic ore in Siping city had produced wastewater containing ytterbium, which has caused certain environmental pollution. In view of the low removal efficiency of ytterbium in wastewater, we developed a novel PAN microtube ultrafilter device with organic P-204 system (UF-OP). The UF-OP had organic P-204 system containing wastewater part with buffer solution acetic acid and enrichment part with nitric acid solution and organic P-204[Di(2-ethylhexyl) phosphoric acid] dissolved in gasoline. Many factors of ytterbium(III) extraction using UF-OP need to explore. The effects of hydrodynamic properties and UF system parameters on the UF-OP process for ytterbium(III) extraction were also studied. The experimental results show that the best extraction conditions of ytterbium(III) were obtained as that nitric acid concentration was 4.00 mol/L, organic P-204 concentration was 0.150 mol/L, and O/W was 0.5 in the enrichment part, and pH value was 4.80 in the wastewater part. Ionic strength of metallic ore wastewater had no obvious effect on ytterbium(III) extraction. When cinit of ytterbium(III) concentration was 1.48 × 10−4 mol/L, the extraction percentage of ytterbium(III) was up to 94.8% in 160 min. The study results would provide theoretical and technical support for the treatment of wastewater containing ytterbium in metallic ore. [ABSTRACT FROM AUTHOR]

In this study, p-morpholinomethylcalix[4]arene (p-MC4) was synthesized using Mannich reaction and utilized for the fabrication of polyacrylonitrile nanofibers impregnated with p-morpholinomethylcalix[4]arene (PAN/p-MC4) using electrospinning. The nanofibers were prepared by blending 12% solution of PAN with 20% solution of p-MC4. The PAN/p-MC4 NFs were thoroughly evaluated for their removal efficiency of Cu2+ from the aqueous media. The selectivity of PAN/-p-MC4 nanofibers was also examined by adsorbing a set of metal ions with same charge and similar ionic radius. The results of distribution ratio showed that PAN/p-MC4 nanofibers have superior selectivity for Cu2+ as compared to other heavy metal ions. The relative selectivity coefficients of PAN/p-MC4 nanofibers were found to be 25.2, 14.1, 8.9, and 4.03 for Cu2+/Ni2+, Cu2+/Co2+, Cu2+/Cd2+ and Cu2+/Pb2+, respectively. This indicates that PAN/p-MC4 nanofibers have a higher selectivity for Cu2+ ions. Numerous parameters such as pH, time, adsorbent dosage and analyte concentration were optimized to evaluate the maximum adsorption capacity of nanofibers for Cu2+. Adsorption isotherm models showed that the adsorption is promising and follows Langmuir adsorption isotherm. Whereas, PAN/p-MC4 nanofibers followed pseudo- second order kinetics during adsorption experiments. The PAN/p-MC4 nanofibers showed excellent adsorption capacity (qo) of 65.35 mg/g for Cu2+ at pH 5 in 60 min under shaking speed of 120 rpm. Moreover, PAN/p-MC4 nanofibers had been used to remove Cu2+ from real surface water samples. According to the results, PAN/p-MC4 nanofibers are more effective adsorbent for removing Cu2+ from contaminated water. [ABSTRACT FROM AUTHOR]

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Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of the present study was to evaluate the carbon fiber obtained from textile PAN fiber, in its different forms, as a potential scaffolds synthetic bone. Thirty‐four adult rats were used (Rattus norvegicus, albinus variation), two critical sized bone defects were made that were 5 mm in diameter. Twenty‐four animals were randomly divided into four groups: control (C)—bone defect + blood clot, non‐activated carbon fiber felt (NACFF)—bone defect + NACFF, activated carbon fiber felt (ACFF)—bone defect + ACFF, and silver activated carbon fiber felt (Ag‐ACFF)—bone defect + Ag‐ACFF, and was observed by 15 and 60 days for histomorphometric, three‐dimensional computerized microtomography (microCT) and mineral apposition analysis. On histomorphometric and microCT analyses, NACFF were associated with higher proportion of neoformed bone and maintenance of bone structure. On fluorochrome bone label, there was no differences between the groups. NACFF has shown to be a promising synthetic material as a scaffold for bone regeneration. [ABSTRACT FROM AUTHOR]

It is a vital route to develop new fiber products with various physical‐mechanical properties by which their aggregation structure can be changed via controlling the spinning process parameters. In this study, five groups fiber samples had been obtained by changing the spinneret drawing ratio, two stages drawing ratio and two stages heat‐setting rate. The aggregation structure of the poly(ethylene terephthalate) (PET) industrial fibers from different spinning process was analyzed by combination use of thermal analysis, two‐dimensional wide‐angle X‐ray diffraction (WAXD), small‐angle X‐ray scattering (SAXS), and Infrared Spectroscopy (IR) measurements. It was found that, increasing the spinneret drawing ratio and two stages drawing ratio promoted the orientation and crystallinity within a certain range. For the subsequent two stages heat‐setting process, the disorientation of the amorphous chain is simulated by reducing the relaxation rate and heat setting temperature. Finally, a concise three‐dimensional structure model was established to explain the relationship between aggregation structure and property. These results have important reference for the structure and property analysis of polyester industrial fiber. [ABSTRACT FROM AUTHOR]

Multifunctional CDs doping enhances the properties of CDs/ZIS/PAN nanofiber membrane: increased the hydrophilicity, promoted the light absorption, facilitated the transfer of photogenerated electrons. [Display omitted] Recent progress in the co-spinning of nanofibers and semiconductor particles offers a promising strategy for the development of photocatalytic devices, solving aggregation and catalyst recovery challenges. However, composite photocatalysts based on nanofiber membranes often suffer from poor conductivity, low hydrophilicity, and easy recombination of photogenerated electron-hole pairs in the semiconductor components. Here, to tackle the aforementioned issues of ZnIn 2 S 4 /polyacrylonitrile (ZIS/PAN) nanofiber-based catalysts, we prepared a composite carbon dots/ZnIn 2 S 4 /polyacrylonitrile (CZP) nanofiber membrane by blending carbon dots (CDs) with ZIS/PAN using the electrospinning process. The hydrogen evolution performance of the CZP photocatalyst was significantly improved by CDs, which enhanced the hydrophilicity, increased the light absorption, facilitated the transfer of photogenerated electrons, and reduced the recombination of photogenerated electron-hole pairs. Notably, the optimal CZP photocatalyst achieved a hydrogen evolution rate of 2250 μmol g-1h−1, which is about 23 % higher than that of the nanofiber membrane without CDs and 4.55 times higher than that of ZIS particles. The present work successfully improved the CZP nanofiber membrane of photocatalytic hydrogen evolution performance, and the membrane may benefit further device development by eliminating the need for stirring and simplifying the recovery process. [ABSTRACT FROM AUTHOR]

[Display omitted] Layered double hydroxide (LDH)-carbon composites effectively mitigate the inherent issues of agglomeration and poor conductivity in LDH. However, the weak binding energy and insufficient charge transfer capability between LDH and carbon substrate significantly compromise the active substance loading, cyclic stability and practical capacity of the composites. Herein, N/O co-doping porous carbon nanofibers (NOPCNFs) are first prepared by blending diminutive zinc imidazolate framework-8 nanoparticles with polyacrylonitrile for electrospinning, and then densely packed NiCo LDH nanosheets are homogeneously anchored on NOPCNFs to form NiCo LDH@NOPCNFs heterostructure via a hydrothermal method. The experimental findings and density functional theory calculation results indicate that N/O atoms exhibit robust binding forces with metal atoms through enhanced electrostatic adsorption and p-d covalent hybridization, which facilitates the nucleation and development of NiCo LDH on carbon nanofibers. Meanwhile, these heteroatoms also serve as the bridge for electron transfer from NiCo LDH to NOPCNF, leading to a strong interfacial electric field, thus accelerating charge transfer behaviors. Benefitting from the synergistic interaction between NiCo LDH and NOPCNF, the obtained NiCo LDH@NOPCNFs demonstrate an elevated mass loading of active substance (55 wt%), an impressive specific capacitance of 1340 F/g at 1 A/g (based on the mass of NiCo LDH, 2463 F/g), and good cyclic durability for 5000 cycles. Moreover, an all-solid-state asymmetric supercapacitor using NOPCNFs and NiCo LDH@NOPCNFs shows promising practical application prospects. This work gives insights into the important influence of heteroatom doping in carbon, and provides a feasible approach for the efficient integration of electroactive and carbon material. [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]

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]

Polymer gel electrolytes (PGE) have seen a renewed interest in their development because they have high ionic conductivities but low electrochemical degradation and flammability. PGEs are formed by mixing a liquid lithium-ion electrolyte with a polymer at a sufficiently large concentration to form a gel. PGEs have been extensively studied, but the direct connection between their microscopic structure and macroscopic properties remains controversial. For example, it is still unknown whether the polymer in the PGE acts as an inert, stabilizing scaffold for the electrolyte or it interacts with the ionic components. Here, a PGE composed of a prototypical lithium-carbonate electrolyte and polyacrylonitrile (PAN) is pursued at both microscopic and macroscopic levels. Specifically, this study focused on describing the microscopic and macroscopic changes in the PGE at different polymer concentrations. The results indicated that the polymer-ion and polymer–polymer interactions are strongly dependent on the concentration of the polymer and the lithium salt. In particular, the polymer interacts with itself at very high PAN concentrations (10% weight) resulting in a viscous gel. However, the conductivity and dynamics of the electrolyte liquid components are significantly less affected by the addition of the polymer. The observations are explained in terms of the PGE structure, which transitions from a polymer solution to a gel, containing a polymer matrix and disperse electrolyte, at low and high PAN concentrations, respectively. The results highlight the critical role that the polymer concentration plays in determining both the macroscopic properties of the system and the molecular structure of the PGE. [ABSTRACT FROM AUTHOR]

Polymer electrolyte membranes with superior lithium‐ion (Li+) conductivity and sufficient electrochemical stability are desired for all‐solid‐state lithium‐ion batteries (ASS‐LIBs). This paper reports novel polymer composite membranes consisting of polyacrylonitrile (PAN) nanofibers (Nfs) containing lithium salts. It is first revealed that the lithium salt addition increases polar surface groups on the PAN nanofibers. Subsequently, the lithium salts‐containing PAN nanofiber (PAN/Li Nf) composite membrane affects the matrix poly(ethylene oxide) (PEO)/lithium bis(trifluoromethyl sulfonylimide) (LiTFSI) electrolyte to increase the numbers of Li+ with high mobility. Consequently, the PAN/Li Nf composite membrane shows relatively good ion conductivity (σ = 9.0 × 10−5 S cm−1) and a considerably large Li+ transference number (tLi+ = 0.41) at 60 °C, compared to the PEO/LiTFSI membrane without nanofibers. The 6Li solid‐state NMR study supports that the PAN/Li Nf bearing abundant polar nitrile groups at their surface enhances Li+ diffusion in the PEO‐based electrolyte membranes. The galvanostatic constant current cycling tests reveal that the PAN/Li Nf composite membrane possesses good electrochemical and mechanical stabilities. The ASS‐LIB consisting of the PAN/Li Nf composite membrane shows significantly improved charge and discharge cycling performances, promising future all‐solid‐state batteries. [ABSTRACT FROM AUTHOR]

This study introduces a novel microwave applicator and optimized processing conditions to enhance the stability of Polyacrylonitrile (PAN)-based precursor fiber (PF). The innovative microwave applicator facilitates the propagation of the electromagnetic (EM) field akin to a quasi-traveling wave, thus circumventing standing wave nodes. This ensures a uniform thermal distribution and broadens the heating zone. Utilizing this applicator, the PF undergoes thermal stabilization in a streamlined two-step process, completing in just 13 min, a significant improvement over the conventional 90-min process. This not only saves manufacturing time, promoting energy efficient manufacturing but also aligns with the global trend towards green energy and lightweight carbon fiber-reinforced polymer matrix composites, potentially catalyzing rapid economic growth. Fiber characterization through Raman spectroscopy (RS), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and complex permittivity measurements reveals that the microwave-processed fiber meets the standard of commercial stabilization fiber (SF). [ABSTRACT FROM AUTHOR]

Nanostructured porous materials are desirable sorbents for separating and removing oil spills from water. This work examines the performance of the prepared efficient sorbents in the oil sorption process. Polyacrylonitrile (PAN) fibers served as the skeleton matrix, while glutaraldehyde and poly(vinyl alcohol) (PVA) served as cross-linking agents. The prepared polymer sorbents showed high adsorption capacity (12.47 g/g), porosity (95.41%) and low density (0.069 g/cm3). The incorporation of carbon nanostructures (nanotubes or graphene oxide) in the sorbent increased the adsorption capacity to 14.85 g/g. The hydrophobic nature of carbon nanotubes significantly increases the contact angle of water with the surface of the nanocomposite absorber and reaches 137.5 degrees. The obtained sorbents showed good reusability in the adsorption process and maintained an adsorption capacity of about 10 g/g after 5 cycles. The optimal temperature range for using nanocomposite sorbents was 25°C to 35°C. The combination of high sorption capacity, low porosity and density in modified polyacrylonitrile, along with its reusability, makes this designed sorbent highly suitable for efficient removal of oil spills. [ABSTRACT FROM AUTHOR]

Graphitic carbon plays a pivotal role in numerous technological applications, including energy storage, energy conversion, and different fields of material science. The transformation of amorphous carbon into graphitic carbon, a process known as graphitization, is important for optimizing the properties of carbon materials. In this study, we explore the catalytic graphitization of polyacrylonitrile (PANs) using various metal salts (LiNO3, Ca(NO3)2·4H2O, and Ni(NO3)2·6H2O). We prepared dimethyl sulfoxide (DMSO) solutions of PAN with different salt concentrations of 5, 10, and 15 wt.%. The different prepared metal salt-mixed PAN/DMSO solutions were dried at 45 °C and this was followed by carbonization processes at 950 °C, with a heating rate of 1 °C min−1 for 1 h under an N2 atmosphere. The resulting graphitic carbon was characterized to determine the influence of salt type and concentration on the degree of graphitization. Our findings provide valuable insights into PAN-derived graphitic carbon's structural and compositional properties. This work underscores the influence of salt concentration in optimizing the graphitization process, offering a pathway to design facile and cost-effective graphitic carbon materials. [ABSTRACT FROM AUTHOR]

Currently, the number of patients with cancer is expanding consistently because of a low quality of life. For this reason, the therapies used to treat cancer have received a lot of consideration from specialists. Numerous anticancer medications have been utilized to treat patients with cancer. However, the immediate utilization of anticancer medicines leads to unpleasant side effects for patients and there are many restrictions to applying these treatments. A number of polymers like cellulose, chitosan, Polyvinyl Alcohol (PVA), Polyacrylonitrile (PAN), peptides and Poly (hydroxy alkanoate) have good properties for the treatment of cancer, but the nanofibers-based target and controlled drug delivery system produced by the co-axial electrospinning technique have extraordinary properties like favorable mechanical characteristics, an excellent release profile, a high surface area, and a high sponginess and are harmless, bio-renewable, biofriendly, highly degradable, and can be produced very conveniently on an industrial scale. Thus, nanofibers produced through coaxial electrospinning can be designed to target specific cancer cells or tissues. By modifying the composition and properties of the nanofibers, researchers can control the release kinetics of the therapeutic agent and enhance its accumulation at the tumor site while minimizing systemic toxicity. The core–shell structure of coaxial electrospun nanofibers allows for a controlled and sustained release of therapeutic agents over time. This controlled release profile can improve the efficacy of cancer treatment by maintaining therapeutic drug concentrations within the tumor microenvironment for an extended period. [ABSTRACT FROM AUTHOR]

In the pursuit of fabricating functional ceramic nanostructures, the design of preceramic functional polymers has garnered significant interest. With their easily adaptable chemical composition, molecular structure, and processing versatility, these polymers hold immense potential in this field. Our study succeeded in focusing on synthesizing ferrocene-containing block copolymers (BCPs) based on polyacrylonitrile (PAN). The synthesis is accomplished via different poly(acrylonitrile-block-methacrylate)s via atom transfer radical polymerization (ATRP) and activators regenerated by electron transfer ATRP (ARGET ATRP) for the PAN macroinitiators. The molecular weights of the BCPs range from 44 to 82 kDa with dispersities between 1.19 and 1.5 as determined by SEC measurements. The volume fraction of the PMMA block ranges from 0.16 to 0.75 as determined by NMR. The post-modification of the BCPs using 3-ferrocenyl propylamine has led to the creation of redox-responsive preceramic polymers. The thermal stabilization of the polymer film has resulted in stabilized morphologies based on the oxidative PAN chemistry. The final pyrolysis of the sacrificial block segment and conversion of the metallopolymer has led to the formation of a porous carbon network with an iron oxide functionalized surface, investigated by scanning electron microscopy (SEM), energy dispersive X-ray mapping (EDX), and powder X-ray diffraction (PXRD). These findings could have significant implications in various applications, demonstrating the practical value of our research in convenient ceramic material design. [ABSTRACT FROM AUTHOR]

The multilayer composite film system was designed in this study. The multilayer composite film was constructed by alternating electrospinning of MXene doped with polyacrylonitrile (PAN) nanofilm and thermoplastic polyurethane (TPU) nanofilm as piezoelectric functional layer. After utilizing nanofilm material, the piezoelectric sensor was prepared and subsequently examined for its piezoelectric sensitivity, piezoelectric output, and mechanical characteristics. MXene/PAN/TPU multilayer composite films showed good piezoelectric output performance. The final experimental data showed that the piezoelectric sensor of the MXene/PAN/TPU-based system achieved 0.16 kPa−1 piezoelectric sensitivity, 150ms/140ms response time and recovery time, good output voltage and output current, and good output stability. In human biological motion detection, the generator produced a maximum output voltage of 30 V when pressed by the palm. Tests such as palm pressing, finger tapping, and footstomping demonstrated the potential of piezoelectric sensors in human energy harvesting and motion monitoring. Multilayer composite films had flexible mechanical properties and sensitive piezoelectric response and had broad application prospects in piezoelectric sensors and piezoelectric nanogenerators. [ABSTRACT FROM AUTHOR]

Traditional separation membranes used for dye removal often suffer from a trade-off between separation efficiency and water permeability. Herein, we propose a facile approach to prepare cyclodextrin-based high-flux nanofiber membranes by electrospinning and vapor-driven crosslinking processes. The application of glutaraldehyde vapor for crosslinking hydroxypropyl-β-cyclodextrin (HP-β-CD)/polyvinyl alcohol (PVA)/laponite electrospun membranes can build interconnected structures and lead to the formation of a porous hierarchical layer. In addition, the incorporation of inorganic salt, laponite, can alter the crosslinking process, resulting in membranes with improved hydrophilicity and highly maintained electrospun nanofibrous morphology, which contributes to an ultrafast water flux of 1.0 × 105 Lh−1m−2bar−1. Due to the synergetic effect of strong host–guest interaction and electrostatic interaction, the membranes exhibit suitable rejection toward anionic dyes with a high removal efficiency of >99% within a short time and achieve accurate separation for cationic against anionic dyes, accompanied by suitable recyclability with >97% separation efficiency after at least four separation–regenerations. The prepared membranes with remarkable separation efficiency and ultrafast permeation properties might be a promising candidate for high-performance membranes in water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sc3+ is selected to replace V3+ and PAN is introduced to provide porous carbon substrate. • Sc bonds with oxygen to form ScO 6 , resulting in improved structural stability and kinetics. • PAN can induce a beneficial nitrogen-doped carbon skeleton with defects, resulting in enhanced electronic conductivity. • After cycling XRD/SEM confirms the stabilized porous carbon skeleton and improved crystal stability. • Ex-situ XRD analysis reveals the crystal volume change in Sc-3 is relatively slight but reversible. The poor structural stability and conductivity of Na 3 V 2 (PO 4) 3 (NVP) have been serious limitations to its development. In this paper, Sc3+ is selected to replace partial site of V3+ which can enhance its ability to bond with oxygen, forming the ScO 6 octahedral unit, resulting in improved structural stability and better kinetic properties for the NVP system. Moreover, due to the larger ionic radius of Sc3+ compared to V3+, moderate Sc3+ substitution can support the crystal framework as pillar ions and expand the migration channels for de-intercalation of Na+, thus efficiently promoting ionic conductivity. The introduction of polyacrylonitrile (PAN) to provide an N -doped porous carbon substrate is another key aspect. The low-cost carbon resource of PAN can induce a beneficial nitrogen-doped carbon skeleton with defects, enhancing electronic conductivity at the interface to reduce the polarization phenomenon. The established pore structure can serve as a buffer for unit cell deformation caused by Na+ migration. Furthermore, the enlarged specific surface area provides more active sites for electrolyte infiltration, improving the material utilization rate. The after cycling X-ray Diffraction/scanning electron microscope (XRD/SEM) further confirms the stabilized porous carbon skeleton and improved crystal stability of Sc-3 material. Ex-situ XRD analysis shows that the crystal volume change in the Sc-3 cathode is relatively slight but reversible during the charge/discharge process, indicating that Sc3+ doping plays a crucial role in stabilizing the unit cell structure. The hybrid Sc/VO 6 and PO 4 units jointly build a strong bone structure to resist stress and weaken deformation. Accordingly, the optimized Sc-3 sample reveals an initial capacity of 115.9 mAh/g at 0.1C, with a capacity retention of 78.6 % after 2000 cycles at 30C. The Sc-3//CHC full battery can release a capacity of 191.3 mAh/g at 0.05C, accompanied by successful illumination, showcasing its promising practical applications. [ABSTRACT FROM AUTHOR]

Water pollution from industrial wastewater and oil spills, which threat marine lives and mankind continually have turned into one of the most severe challenges in worldwide due to the fast development of global industrialization and human activities. Various water‐treatment methods have been developed to solve the problems. However, these processes are often complicated and costly, making them fail to address the complicate water environment. Herein, a visible light‐responsive Au‐BiOCl/TiO2/PAN composite membrane with hydrophilic surface was prepared by combing electrospinning with solvothermal method. The composite membranes can efficiently separate emulsions with the highest flux of 50.16 L m−2 h−1 and oil/water mixtures (the highest flux was 4777.07 L m−2 h−1 bar−1). Moreover, the membranes can rapidly degrade antibiotics with an excellent degradation rate (95.70% in 60 min) under the visible light. Additionally, they can simultaneously degrade organic dye and separate oil/water emulsions under a gravity condition. It is expected that composite membranes will be an attractive candidate for complex wastewater treatment. [ABSTRACT FROM AUTHOR]

Core‐Shell (CS) polymeric particles have attracted great interest due to their high mechanical, thermal, and chemical stability and their surface properties. In this study, functionalizable CS poly(propylene/styrene)/poly(acrylonitrile) (PP/PS/PAN) particles were prepared through heterogeneous polymerizations in a batch reactor. Commercial PP particles and PP/PS particles (prepared by seeded suspension polymerization of styrene (Sty) on PP spheres) were applied as core components of the final structure, while the shell was prepared through acrylonitrile dispersion polymerization. The degree of swelling of the core particles by Sty played an important role for the adhesion of the PAN shell, which for PP particles was 24 wt%, whereas for PP/PS hybrid particles it was 57 wt%. The particles (PP/PS and CS) were characterized through image analysis, revealing a uniform and smooth surface for PP/PS spheres and a uniform porous shell for CS particles. Particle size distributions, thermal degradation, chemical structures, degrees of crystallinity, and textural properties were also evaluated. The PAN shell adhered to the PP/PS particles without forming a copolymer, and the CS particles formed by a PP/PS core and PAN shell had sizes of 4.54 ± 1.24 mm, specific area of 2.70 m2g−1 and PAN content of 15.98 ± 0.82% (m/m) of total particles. [ABSTRACT FROM AUTHOR]

Silk fibroin is highly susceptible to damage during the extraction process. To address this issue, this study proposes an integrated degumming solution that uses a composite system of Na2CO3 and the surfactant SDS (sodium dodecyl sulfate), combined with ultrasonic treatment. Silk fibroin fibers treated with this method exhibit a smoother and more even surface, with markedly less fiber damage. Compared to the traditional 100 °C alkaline degumming (30 min complete degumming), this scheme completes degumming in only 10 min at 75 °C. Nanofibrous membranes were prepared from these degummed fibers using electrospinning technology, and their β-sheet crystalline content increased to 49.58% after ethanol treatment, along with high tensile strength (5.27 MPa) and elongation at break (123.49%). Over a 5-day cell culture period, the membranes have supported cell adhesion, spreading and proliferation, demonstrating excellent cytocompatibility. These research findings provide a novel solution for the production of high-performance silk fibroin nanofibrous membranes and are expected to advance the application and development of silk fibroin materials in the biomedical field. [ABSTRACT FROM AUTHOR]

To address the limitations of ion-sieve powder in industrial applications and to facilitate the industrial application of lithium extraction through ion sieves, this study utilized the solvent exchange method to prepare a PVC/PAN-H1.6Mn1.6O4 lithium ion-sieve membrane, which exhibited both stable mechanical properties and excellent hydrophilicity. The membrane structure was characterized by XPS, FT-IR, BET, SEM, and other analytical techniques. The results revealed the presence of hydrophilic cyano groups (–C≡N) in the blend ion-sieve membrane, accompanied by micropores with dimensions ranging from 20 nm to 40 nm. Under the conditions of PVC:PAN = 7:3, the binder concentration of 13%, and H1.6Mn1.6O4 content of 25%, the adsorption capacity of the ion-sieve membrane reached 1261.5 mg/m2. The Langmuir adsorption isothermal model and the pseudo-second-order kinetic model indicated that the adsorption process of Li+ followed a multi-step controlled monolayer chemisorption process. Simultaneously, the ion-sieve membrane demonstrated exceptional selectivity and remarkable cycle stability for Li+ in the multi-ion coexistence system. This study provides guidance for the excellent application of lithium ion-sieve membranes in efficiently recovering Li+ from Salt Lake brine. [ABSTRACT FROM AUTHOR]

An important process step in carbon fiber production is the stabilization of the pan precursor fiber, which makes it infusible and incombustible. This article gives a market overview of the carbon fiber producers relating to their used oxidations oven and of market of oxidations oven itself. All six industrially available oxidation oven types are described and an overview of the oven supplier is given. The analysis of the oxidation oven market shows that only three out of six oxidation oven technologies are used for large‐volume production. CtE is currently the most widely used oven technology with approximately 55%. Since 2014, CF demand has been growing faster than the expansion of production capacities. A shortage is predicted within the next 5 years. In addition, the production capacities of existing CF lines have stagnated at an average of 1.5 kt*a−1 since the last 10 years. To meet the increasing CF demand in the coming years, various options are available: (1) Increasing large‐tow production, (2) Increasing process speed (3) Increasing the loading factor (4) Increasing with of oxidation oven. [ABSTRACT FROM AUTHOR]

Phytic acid (PA) modified polyacrylonitrile (PAN) nanofiber membranes for heavy metal adsorption were fabricated using electrospinning for the first time, and its mechanical properties and heavy metal adsorption under various conditions were tested. The results demonstrated that PA modification improved the mechanical properties of PAN nanofiber membranes at low modification ratio due to increased intermolecular hydrogen bonds and cross‐linking. The highest breaking strength and elongation at break were 70.1% and 31.5% over PAN without modification when the PA:PAN ratio was close to 1:5. The Pb2+ absorption tests in the water solutions demonstrated that the optimal PA:PAN ratio was 1:1, the optimal temperature was 30°C, and the optimal pH was 7. With the optimal parameters, the adsorption capacity reached the maximum and equilibrium after 4 h. The adsorption capacities increased with higher initial Pb2+ concentrations. The highest adsorption capacity in this study was approximately 240.1 mg g−1 at the initial Pb2+ concentration of 750.72 mg L−1. In addition, after de‐adsorption process, the 1:1 PA modified membranes maintained 91.9% re‐adsorption capacities compared to primary adsorption. Consequently, the PA‐modified PAN nanofiber membranes showed promising potentials of metal ion adsorption in wastewater treatment. Highlights: Phytic acid modified polyacrylonitrile nanofiber membranes were fabricated.Low ratio modification improved the mechanical properties.The optimal modification ratio for Pb2+ adsorption is 1:1.The maximum Pb2+ adsorption capacity was 240.1 mg g−1 in this study.The membranes maintained 91.9% capacities at re‐adsorption tests. [ABSTRACT FROM AUTHOR]

Facing the shortage of freshwater resources, solar desalination technology provides a solution with its green and environmentally friendly features. However, the traditional desalination strategy has some problems, such as low evaporation efficiency and salt deposition. Herein, asymmetric nanofiber membranes were prepared by electrospinning technology that can realize photothermal conversion and reduce heat loss because of the unique double-layer structure. This evaporator can achieve stable and efficient desalination evaporation efficiencies in highly concentrated brines. What's more, the hydrophilic membrane polyacrylonitrile (PAN) modified with sodium alginate (SA) hydrogel can realize efficient ion distribution. This work presents a new design strategy for the development of highly efficient photothermal conversion materials for use in solar-driven evaporation. [ABSTRACT FROM AUTHOR]