Nanofiber Content Research Articles

Constructing interconnected hierarchical porous structures and nitrogen-doped carbon nanofibers for superior capacitive deionization

Capacitive Deionization (CDI) has emerged as a sustainable and efficient method for desalinating low-salinity water sources. However, CDI materials are often limited by insufficient surface area, slow electron/ion transport, and suboptimal electrolyte wettability, which restrict desalination capacity and rate. Herein, we simultaneously construct interconnected hierarchical porous structures and nitrogen-doping in carbon nanofibers by pyrolyzing polymer nanofiber precursors embedded with Zeolite Imidazolate Framework-8 (ZIF-8) nanoparticles. ZIF-8 nanoparticles serve not only as precise pore-forming templates but also act as a rich source of nitrogen for doping the carbon nanofibers. We optimize the pore structure and nitrogen content of the carbon nanofibers by tuning the diameter of ZIF-8 nanoparticles within the polymer nanofiber precursor, thereby achieving superior CDI performance. This unique structure not only substantially increases the specific surface area and significantly enhances mass transfer processes, but also introduces abundant nitrogen into the porous carbon fibers. This improves their hydrophilicity, adjusts their electronic structure, increases active sites, and greatly boosts the electrodes’ adsorption capacity and desalination efficiency. An electrode constructed from the optimized porous nanofibers with a larger specific surface area (LPCNF) achieves a peak desalination capacity of 68.11 mg/g. Furthermore, the electrode maintains a high salt adsorption capacity (SAC) retention of 93.4 % after 50 cycles, significantly outperforming conventional materials such as activated carbon, graphene, and carbon nanotubes. Overall, the developed method optimizes both the pore structure and enhances the nitrogen content, providing a novel strategy for developing high-performance CDI electrode materials.

A multi-layer antimicrobial cellulose filter with electrostatic adsorption properties prepared by coating cellulose with chitosan and CuO

The health impacts of air pollution such as particulate matter (PM) and bioaerosols have prompted a focus on the utilization of personal protective filters. Traditional filters pose environmental concerns due to their non-biodegradable composition, while cellulose presents a promising alternative for biodegradable air filtration applications. This research involved the development of cellulose filter substrates with a customizable pore structure by adjusting the nanofiber content in cellulose filters and employing a simultaneous freeze-drying method. By integrating chitosan and CuO nanoparticles, the filters gained electrostatic adsorption capabilities, leading to a substantial enhancement in filtration efficiency, as well as imparting moisture resistance and durable antimicrobial properties to the filter. Subsequently, a three-layer cellulose filter integrated with chitosan and CuO (abbreviated as Int-Cs&CuO) was constructed based on the generalized Murray’s law to enable multi-stage PM filtration. The Int-Cs&CuO cellulose filter demonstrated filtration efficiencies of 99.2 % for non-oily PM0.3 and 99.5 % for oily PM0.3, with a low pressure drop of 49.5 Pa. Under humid conditions, the filtration efficiency of the Int-Cs&CuO cellulose filter against PM0.3 particles was minimally impacted, showcasing a decrease of only 1.3 %. Notably, the filter exhibited complete biodegradation in composted soil within approximately 2 months.

Comparative Corrosion Inhibition Test Study in Phosphate Buffer Saline for 316L Stainless Steel with Electrospun PCL Coating with Different Additives

In this study, ten different contents of PCL-based nanofibers containing ZnO, CuO, NiO, 2F TSC, 4F TSC and graphite additives (PCL+Graphite+CuO+NiO+ZnO, PCL+ZnO+Graphite, PCL+ZnO+NiO+CuO, PCL+ZnO, PCL+Graphite, PCL+ZnO+2F TSC, PCL+ZnO+NiO+CuO+4F TSC, PCL+ZnO+NiO+CuO+2F TSC, bare PCL, PCL+ZnO+4F TSC) 316L stainless steel (SS) surface was coated. After coating with these different types of nanofibers, measurements were taken with electrochemical techniques such as potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) in phosphate buffer solution (PBS) for 1 hour to investigate the corrosion inhibition properties. According to the results, the PCL+Graphite+CuO+NiO+ZnO coating provided the highest corrosion inhibition with a protection efficiency value of 98.83%. The PCL+4F+ZnO coating had the lowest inhibition property with a protection efficiency value of 40.72%. At the end of the tests, Nyquist, Bode, Tafel, OCP diagrams of the coatings were obtained and equivalent circuit models were presented.

Cellulose nanofiber aerogels: effect of the composition and the drying method

Highly porous and lightweight aerogels of cellulose nanofibers (CNFs) have emerged as a promising class of material. This study delves into the impact of the composition (lignocellulose nanofibers–LCNFs and CNFs) and the drying methods (supercritical drying and freeze-drying) on the morphology and the properties of nanocellulose-based aerogels. The investigation evaluates the concentrations of nanofibers and the influence of lignin, a constituent of LCNFs recognized for enhancing the rigidity of plant cell walls, on the aerogel’s properties. The shrinkage rates, density, pore structure, and mechanical properties of the obtained aerogels are comprehensively compared. Supercritical drying proves advantageous for aerogel formation, resulting in materials with lower density and higher surface area than their freeze-dried counterparts at each concentration level. The use of acetone for supercritical drying contributes to reduce the shrinkage rates compared to ethanol. This decrease is attributed to the formation of a more rigid hydrogel during solvent exchange. Freeze-drying exhibits the lowest shrinkage rates and relatively higher porosity. The presence of lignin in the nanofibers influences the microstructure, yielding smoother and thicker pore walls. This study contributes to the comprehensive understanding of the intricate factors shaping nanocellulose aerogel properties, paving the way for the development of innovative and environmentally-friendly materials.

Polyacrylamide/Cellulose Nanofibers Composite As Quasi Solid Electrolyte for Rechargeable Zinc-Ion-Battery

This research aims to optimize the cellulose nanofiber content in polyacrylamide (PAM) using as quasi-solid electrolyte composites for zinc-ion batteries (ZIBs). The cellulose nanofibers (CNFs) derived from hemp were prepared via alkaline treatment and bleaching process, followed by mechanical defibrillation. The chemical functional group analysis confirmed the successful extraction of lignin and cellulose from hemp fiber. The improved thermal stability of cellulose nanofibers indicated the success of the chemical treatment in removing non-cellulosic components. Furthermore, quasi-solid electrolyte composites of PAM / CNFs at 0.25, 0.5, 0.75, and 1 wt.% of cellulose nanofibers were prepared. At 1 wt.% CNFs addition, PAM / CNFs composites showed the highest values for electrolyte uptake, and electrochemical impedance spectroscopy with the highest ion conductivity of 59.6 mS cm-1. For the plating/stripping testing with symmetrical zinc cell, PAM / CNFs at 1.0 %wt CNF also demonstrated the lowest overpotential with the best zinc dendrite suppression feature. For zinc-ion battery performance test, the quasi-solid electrolyte composites of PAM / CNFs at 1.0 %wt CNF were fabricated and employed with electrochemical properties testing, including cyclic voltammetry, galvanostatic charge-discharge, electrochemical impedance spectroscopy, and cycle stability. This optimized quasi-solid electrolyte composites reached the highest specific capacity of 134.2 mA g-1 at a current density of 0.1 A g-1 and maintained capacity retention of 90.8% of initial capacity with 94.4% coulombic efficiency after 500 cycles.

Effect of Glycerol and Sisal Nanofiber Content on the Tensile Properties of Corn Starch/Sisal Nanofiber Films.

Currently, petroleum-derived plastics are widely used despite the disadvantage of their long degradation time. Natural polymers, however, can be used as alternatives to overcome this obstacle, particularly cornstarch. The tensile properties of cornstarch films can be improved by adding plant-derived nanofibers. Sisal (Agave sisalana), a very common low-cost species in Brazil, can be used to obtain plant nanofibers. The goal of this study was to obtain sisal nanofibers using low concentrations of sulfuric acid to produce thermoplastic starch nanocomposite films. The films were produced by a casting technique using commercial corn starch, glycerol, and sisal nanofibers, accomplished by acid hydrolysis. The effects of glycerol and sisal nanofiber content on the tensile mechanical properties of the nanocomposites were investigated. Transmission electron microscopy findings demonstrated that the lowest concentration of sulfuric acid produced fibers with nanometric dimensions related to the concentrations used. X-ray diffraction revealed that the untreated fibers and fibers subjected to acid hydrolysis exhibited a crystallinity index of 61.06 and 84.44%, respectively. When the glycerol and nanofiber contents were 28 and 1%, respectively, the tensile stress and elongation were 8.02 MPa and 3.4%. In general, nanocomposites reinforced with sisal nanofibers showed lower tensile stress and higher elongation than matrices without nanofibers did. These results were attributed to the inefficient dispersion of the nanofibers in the polymer matrix. Our findings demonstrate the potential of corn starch nanocomposite films in the packaging industry.

Effect of TiO2 Nanofiber Content on Compressive Strength of Geopolymers Fabricated from Waste Clay

Effect of TiO2 Nanofiber Content on Compressive Strength of Geopolymers Fabricated from Waste Clay

Anti-Leishmanial Effects of a Novel Biocompatible Non-Invasive Nanofibers Containing Royal Jelly and Propolis against Iranian Strain of Leishmania major (MRHO/IR/75/ER): an In-Vitro Study.

Current medications especially the pentavalent antimonial compounds have been used as the first line treatment of cutaneous leishmaniasis (CL), but they have limitations due to serious side effects such as drug resistance, cardio and nephrotoxicity, and high costs. Hence, the demand to find more usable drugs is evident. Synthesis and development of natural, effective, biocompatible, and harmless compounds against Leishmania major is the principal priority of this study. By electrospinning method, a new type of nanofiber were synthesized from royal jelly and propolis with different ratios. Nanofibers were characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), Thermogravimetric Analysis (TGA), Contact angle, and Fourier-transform infrared spectroscopy (FTIR). The Half-maximal inhibitory concentration (IC50), Half-maximal effective concentration (EC50) and the 50% cytotoxic concentration (CC50) for different concentrations of nanofibers were determined using quantitative calorimetric methods. Inductively coupled plasma-optical emission spectrometry (ICP-OES) and flow cytometry were performed as complementary tests. The results showed that the proposed formulas provide a new achievement that, despite the significant killing activity on L. major, has negligible cytotoxicity on the host cells. Royal jelly nanofibers have significantly shown the best 72 hours results (IC50= 35 μg/ml and EC50=16.4 μg/ml) and the least cytotoxicity. This study presents a great challenge to introduce a new low-cost treatment method for CL, accelerate wound healing, and reduce scarring with minimal side effects and biocompatible materials. Royal jelly and propolis nanofibers significantly inhibit the growth of L. major in-vitro.

Exploring Cellulose Triacetate Nanofibers as Sustainable Structuring Agent for Castor Oil: Formulation Design and Rheological Insights.

Developing gelled environmentally friendly dispersions in oil media is a hot topic for many applications. This study aimed to investigate the production of electrospun cellulose triacetate (CTA) nanofibers and to explore their potential application as a thickening agent for castor oil. The key factors in the electrospinning process, including the intrinsic properties of CTA solutions in methylene chloride (DCM)/ethanol (EtOH), such us the shear viscosity, surface tension, and electrical conductivity, were systematically studied. The impact of the CTA fiber concentration and the ratio of DCM/EtOH on the rheological properties of the gel-like dispersions in castor oil was then investigated. It was found that dispersions with a non-Newtonian response and above a critical concentration (5 wt.%), corresponding to approximately 2-2.5 times the entanglement concentration, are required to produce defect-free nanofibers. The average fiber diameter increased with CTA concentration. Further, the morphology and texture of the electrospun nanofibers are influenced by the ratio of solvents used. The rheological properties of dispersions are strongly influenced by the concentration and surface properties of nanofibers, such as their smooth or porous textures, which allow their modulation. Compared to other commonly used thickeners, such as synthetic polymers and metal soaps, CTA electrospun nanofibers have a much higher oil structuring capacity. This work illustrated the potential of using CTA nanofibers as the foundation for fabricating gel-like dispersions in oil media, and thus exerting hierarchical control of rheological properties through the use of a nanoscale fabrication technique.

Enhancing heat dissipation in polyurethane sheets through the incorporation of freeze‐dried aluminum nitride nanofiber

AbstractInspired by a three‐dimensional (3D) structure, we demonstrate 3D aluminum nitride (AlN) nanofibers fabricated by a freeze‐drying technique using polyvinyl alcohol (PVA)/boehmite precursor nanofibers. After applying hot pressing, a series of PVA/boehmite precursor nanofibers were prepared with varying PVA‐to‐boehmite ratios (30/70 wt%, 50/50 wt%, and 70/30 wt%). Our findings reveal that the thermal conductivity of the AlN composite nanofibers is significantly affected by the relative proportions of PVA and boehmite, where the ratio of PVA should be more significant than that of boehmite. We produced AlN nanofibers at a lower temperature (1500°C) than the theoretical formation temperature of AlN (1664°C). The minimum specific surface area and pore volumes were 8.39 m2/g and 0.0166 cm3/g, respectively, at 1500°C. X‐ray photoelectron spectroscopy spectra measured 38.27% aluminum and 23.55% nitrogen in AlN nanofibers. The aligned AlN nanofibers mat was impregnated with polyurethane (PU), which showed good thermal conductivity in the planar (4.1–13.6 W/(m·K)) and thickness (1.5–4.9 W/(m·K)) directions at 18–56 vol% AlN nanofibers content. The heat‐dissipating sheet also showed superior electrical insulating (1.2 × 1012 Ω/cm2) properties. In this study, the author sought to develop a heat‐spreading material made of thermally conductive, but electrically insulating PU/AlN nanofibers that could efficiently dissipate heat from electric devices.

Influence of chitin nanofibers and gallic acid on physical-chemical and biological performances of chitosan-based films

In this work, chitosan films loaded with gallic acid and different content of chitin nanofibers were prepared and subjected to different characterization techniques. The results showed that the inclusion of gallic acid to chitosan films caused moderate decrease in water vapor permeability (by 29 %) and increased tensile strength of films (by 169 %) in comparison to the neat chitosan films. Furthermore, it was found that the addition of chitin nanofibers up to 30 % into chitosan/gallic acid films additionally improved tensile strength (by 474 %) and reduced plasticity of films (by 171 %), when compared to the chitosan/gallic acid films. Increased concentration of chitin nanofibers in films reduced the overall water vapor permeability of films by 51 %. In addition, gallic acid and chitin nanofibers had synergic effect on high chitosan film's antioxidant and antifungal activity toward Botrytis cinerea (both above 95 %). Finally, chitosan/gallic acid/chitin nanofibers films reduced decay incidence of strawberries, increased total soluble solid content, and promoted high production of some polyphenols during cold storage, in comparison to the control chitosan films and uncoated strawberry samples. Hence, these results suggest that chitosan/gallic acid/chitin nanofibers can present eco-sustainable approach for preservation of strawberries, giving them additional nutritional value.

Piezoelectric PVDF‐TrFE nanocomposite mats filled with BaTiO3 nanofibers: The effect of poling conditions

AbstractBaTiO3 nanofibers (BT NFs), prepared by electrospinning, were used as a filler for electrospun poly(vinylidene fluoride‐co‐trifluoroethylene) (PVDF‐TrFE) nanocomposite mats. The phase structure and the effect of poling conditions on the piezoelectric properties of PVDF‐TrFE/BT nanocomposites were investigated. The results showed an improved degree of crystallinity (78.6%) and a high β‐crystal phase (up to 98.3%) in all electrospun samples, independent of the nanofiber content. The two‐step poling method, applying electric fields of opposite polarity, led to significantly improved piezoelectric constants d33 (−31.7 pC N−1), strongly dependent on the added BaTiO3 nanofibers. The inclusion of piezoelectric ceramic nanofibers into a polymer matrix, easily carried out by means of electrospinning, followed by an ad hoc optimized poling treatment, allowed to develop flexible materials with enhanced piezoelectric properties, potentially exploitable in innovative conversion systems used in wearable and sensing devices.

Effect of different forms of nanocellulose on the stability of pork myofibrillar proteins' emulsion system

SummaryMyofibrillar proteins (MP) and two forms of nanocellulose (cellulose nanofibers [CNFs] and cellulose nanocrystals [CNCs]) were used to prepare oil‐in‐water emulsion. The effect of CNFs and CNCs on the properties of pork MP‐lard emulsion was studied by analysing the emulsion index, microstructure, oil droplet size, zeta potential and rheological behaviour of emulsion. The results showed that both CNFs and CNCs improved MP‐lard emulsion stability. At the same nanofiber concentration, the creaming index of CNFs stabilised emulsion was lower than that of CNCs stabilised emulsion, especially at the concentration of 0.5%, emulsion prepared with CNFs has no phenomenon of creaming index, while emulsion prepared with CNCs still has creaming index phenomenon. At the same nanofiber concentration, the oil droplet distribution of CNFs stabilised emulsion was more uniform, especially at low concentrations (≤0.5%). At higher cellulose concentration (≥0.75%), the particle size of CNFs stabilised emulsion was larger than that of CNCs stabilised emulsion. CNFs stabilised emulsion had a higher zeta potential and modulus than that of CNCs stabilised emulsion and the emulsion formed by CNFs was more viscoelastic.

Gelatin-reinforced cellulose nanofiber composite cryogels for effective separation of small particulate matter in air

Herein, novel composite aerosol filters solely comprising renewable materials were designed using gelatin as a reinforcement agent and aqueous tert-butyl alcohol (TBA) as a dispersing medium for the cellulose nanofiber skeleton. The prepared composite cryogels exhibited distinct spider-web-like crosslinked structures and nanoporous architectures with porosity exceeding 98.8 % and density of less than 0.018 g/cm3. These composite filters exhibited high filtration efficiency and a robust and flexible mechanical structure due to gelatin reinforcement; furthermore, their quality factor exceeded the target threshold of 0.01 Pa−1 for 300 nm particle size. The filtration performance and mechanical properties of the composite filters could be tailored by adjusting the cellulose nanofiber (CNF), gelatin, and TBA contents, enabling the preparation of cryogels with a firm and strong structure. This study introduces ultraporous solids based on nanocellulose (NC) cryogels, which are promising, novel, and green materials for the production of advanced high-performance filter media for aerosol separation. Furthermore, the aforementioned approach is promising for the preparation of mechanically robust nanoporous biomaterials suitable for diverse applications such as heat and thermal insulation.

Bionanocomposite Based on Cassava Waste Starch, Locust Bean Galactomannan, and Cassava Waste Cellulose Nanofibers.

Natural polysaccharides are among the renewable sources with great potential for replacing petroleum-derived chemicals as precursors to produce biodegradable films. This study aimed to prepare biopolymeric films using starch extracted from the periderm and cortex of cassava roots (waste from cassava root processing), locust bean galactomannan, and cellulose nanofibers also obtained from cassava waste. The films were prepared by casting, and their physicochemical, mechanical, and biodegradability properties were evaluated. The content of cellulose nanofibers varied from 0.5 to 2.5%. Although the addition of cellulose nanofibers did not alter the mechanical properties of the films, it significantly enhanced the vapor barrier of the films (0.055 g mm/m2 h kPa-2.5% nanofibers) and their respective stabilities in aqueous acidic and alkaline media. All prepared films were biodegradable, with complete degradation occurring within five days. The prepared films were deemed promising alternatives for minimizing environmental impacts caused by the disposal of petroleum-derived materials.

Formaldehyde gas sensors based on a quartz crystal microbalance modified with aniline-doped polyvinyl acetate nanofibers.

Real-time detection of formaldehyde in the atmosphere remains challenging. The available gaseous formaldehyde sensing methods offer limited sensitivity, selectivity, and robustness. We modified a quartz crystal microbalance (QCM) system for selective detection of formaldehyde in air. The QCM surface was functionalized with polyvinyl acetate (PVAc) nanofibers and doped with 2, 4, and 6 wt% aniline to improve the selectivity and sensitivity of the sensor. The chemical content and morphological structure of PVAc nanofibers doped with aniline were confirmed by Fourier-transform infrared (FTIR) spectroscopy, energy-dispersive X-ray (EDX) spectroscopy, and scanning electron microscopy (SEM). The results showed that the modified QCM sensor had a sensitivity of 0.056 Hz ppm-1 with a response and recovery times of 200 s and 90 s, respectively. It gave limits of detection (LOD) and limit of quantification (LOQ) of 28 ppm and 96 ppm, respectively. Moreover, the modified QCM was selective towards formaldehyde compared to the other gases. The current workplace exposure limit (WEL) for formaldehyde is 2 ppm, with a time-weighted average over eight hours. Future work will focus on improving the reported QCM sensor to meet the required LOD for formaldehyde detection in the environment and industrial sites.

Borax cross-linked guar gum hydrogel-based self healing polymer electrolytes filled with ceramic nanofibers towards high-performance green energy storage applications

An inventive concept towards the implementation of green energy-storing devices is the synthesis of hydrogel-based gel electrolytes from biopolymers imbued with self-healing capabilities. However, these electrolytes have drawbacks, such as low mechanical stability due to inadequate cross-linking and limited ionic conductivity compared to synthetic polymers. This work develops and characterizes a flexible self-healing hydrogel polymer electrolytes (HPEs) based on guar gum (GG) hydrogel for use in energy storage devices. Hydrogel is prepared with silicon dioxide (SiO2) nanofibers dispersed into borax-bonding cross-linked guar gum. Propylene carbonate (PC) and diethyl carbonate (DC) in equal amounts and lithium perchlorate (LiClO4) are used as plasticizers and salt, respectively. It has been found that adding nanofibers to the hydrogel and spreading them there considerably increases the ionic conductivity as evaluated by ac impedance spectroscopy. When the nanofiber concentration is 5 wt% (wt%), the hydrogel electrolytes reach their maximum room temperature ionic conductivity of 4.3 × 10−3 S cm−1. XRD, FTIR, SEM, and XPS investigations are used to explain the enhanced conductivity caused by the dispersion of nanofibers. Nanofibers also improve the self-healing abilities of materials, as demonstrated by the fact that hydrogels loaded with 5 wt% nanofibers recover from deformation more quickly than hydrogels with lower nanofiber contents. Additionally, the dispersion of nanofibers enhances the hydrogel's mechanical and thermal properties. According to electrochemical investigations and linear sweep voltammetry (LSV) graphs, hydrogel electrolytes are stable up to 4.7 V. When compared to nanofiber-free hydrogels, nanofiber-integrated hydrogel electrolytes show more excellent interfacial stability. The developed self-healing hydrogel-based polymer electrolytes exhibit outstanding promise for a range of energy storage systems, opening the way for creating high-performance and environmentally friendly energy storage solutions.

Mechanical, Crystallization, Rheological, and Supercritical CO2 Foaming Properties of Polybutylene Succinate Nanocomposites: Impact of Carbon Nanofiber Content.

As a substitute for conventional polymers for the preparation of biodegradable microcellular polymeric foams, polybutylene succinate (PBS) presents one of the most promising alternatives. However, the low melt strength of PBS makes it difficult to produce high-performance microcellular foams. This study aimed to improve the melt strength of PBS and explore the mechanical, thermal, crystalline, rheological, and supercritical CO2 foaming properties of PBS nanocomposites by using carbon nanofibers (CNFs). This study found that nanocomposites containing 7 wt% CNF exhibited the highest tensile strength, Young's modulus, and bending strength. Moreover, the CNF nanofillers were well dispersed in the PBS matrix without significant agglomeration, even at high filler concentrations. Furthermore, the nanocomposites demonstrated improved melting temperature and crystallinity compared with pure PBS. The rheological analysis showed that the addition of CNFs significantly increased PBS viscosity at low frequencies due to the interaction between the PBS molecular chains and CNFs and the entanglement of CNFs, resulting in a more complete physical network formation when the CNF content reached above 3 wt%. During the supercritical CO2 foaming process, the addition of CNFs resulted in increased cell density, smaller cells, and thicker cell walls, with good laps formed between the fibers on the cell walls of nanocomposite foams. Moreover, the electrical conductivity and electromagnetic interference (EMI) shielding properties of the foamed material were studied, and a nanocomposite foam containing 7 wt% CNF showed good electrical conductivity (4.5 × 10-3 S/m) and specific EMI shielding effectiveness (EMI SE) (34.7 dB/g·cm-1). Additionally, the nanocomposite foam with 7 wt% CNF also exhibited good compression properties (21.7 MPa). Overall, this work has successfully developed a high-performance, multifunctional PBS-based nanocomposite foam, making it suitable for applications in various fields.

Aligning TiO2 nanofiber for high ionic conductivity in cellulose acetate gel electrolytes

The escalating need for sustainable energy storage systems has prompted enhanced investigations into the advancement of environmentally acceptable, flame-retardant, and high-performing polymer gel electrolytes. The present study examines the ionic conductivity and electrochemical characteristics of gel polymer electrolytes (GPEs) based on cellulose acetate (CA) incorporated with disordered and electric-field-induced aligned TiO2 nanofibers. The results of our study indicate that the arrangement of nanofibers within the CA matrix significantly affects the electrical properties of these electrolytes. The highest ionic conductivity of GPEs containing randomly distributed nanofibers is 5.48 × 10−4 S/cm when the nanofiber content is 2.5 wt%. On the other hand, 2.5 wt% aligned nanofibers containing GPE shows a slightly higher room temperature ionic conductivity of 6.2 × 10−4 S/cm. Nevertheless, the alignment of these nanofibers strategically leads to a gradual enhancement in ionic conductivity, ultimately reaching its maximum value of 5.99 × 10−3 S/cm at a concentration of 10 wt% at room temperature. Significantly, the level of conductivity exhibited in this case is more than 1.5 orders higher than the conductivity observed in disordered nanofiber dispersion within the CA matrix. The improved performance can be due to the creation of long-distance conduction channels enabled by the alignment of nanofibers. The incorporation of well-aligned nanofibers into GPEs results in a high Li+ ion transference number of 0.71, an excellent electrochemical stability window of 4.9 V, and exceptional interfacial compatibility with metal electrodes. In addition, the polymer electrolytes exhibit improved flame-retardant properties when 10 wt% aligned nanofibers are added, enabling the samples to endure exposure to a flame for a period of 10 s. These results indicate the potential suitability of the nanocomposite gel polymer electrolytes (NCGPEs) for application in future advanced energy-storing systems. XRD, FTIR, and XPS investigations further confirm the ion-conduction features of the produced NCGPEs. The investigation of increased electrical characteristics of NCGPEs was supported by a detailed computer simulation conducted using density functional theory (DFT).

Development of polyethersulfone/polylactic acid‐blended nanocellulose membranes for enhanced removal of methylene blue dye

AbstractHerein, adsorptive polyethersulfone/polylactic acid (PES/PLA) blends membranes with systematic concentrations of cellulose nanofibers (CNFs) (0.5–2.5 wt%) were developed via a modified phase inversion process for the enhanced removal of cationic methylene blue (MB) dye. To the best of our knowledge, this is the first time that such adsorptive membranes have been produced for potential use in wastewater treatment. The fabricated membranes were characterized for surface and cross‐sectional morphology (scanning electron microscope), surface roughness (atomic force microscope), functionality (Fourier‐transform infrared spectroscopy), thermal stability (thermal gravimetric analysis), wettability (contact angle measurements), antifouling behavior (flux recovery studies), and dye adsorption and reusability (adsorption and desorption tests). CNF incorporated membranes showed improved wetting properties, with contact angle decreasing from 76° in the pristine membranes to 48° in 2.5 wt% PES/PLA membranes. The membrane bulk porosity increased from 60.3% to 79.23%, while the pure water flux increased from 210.8 to 399.12 Lm−2 h−1. At optimal conditions, CNF‐modified membranes removed >98% of MB compared with 8% removal by the pristine membranes. After five cycles of adsorption and desorption, the membrane with 2 wt% CNFs achieved over 70% dye removal showing excellent reusability properties. Adsorption followed pseudo‐second‐order and Freundlich models. The adsorption was attributed to electrostatic interactions between the negatively charged membrane surfaces and the positively charged dye molecules as well as through hydrogen bonding. Therefore, this work revealed that CNF‐modified PES/PLA membranes can be used as adsorbents for the enhanced removal of organic pollutants in water treatment applications.