Effect of aluminum doped iron oxide nanoparticles on magnetic properties of the polyacrylonitrile nanofibers

Polymers, 2022

Electrospinning can be used to produce nanofiber mats containing diverse nanoparticles for various purposes. Magnetic nanoparticles, such as magnetite (Fe3O4), can be introduced to produce magnetic nanofiber mats, e.g., for hyperthermia applications, but also for basic research of diluted magnetic systems. As the number of nanoparticles increases, however, the morphology and the mechanical properties of the nanofiber mats decrease, so that freestanding composite nanofiber mats with a high content of nanoparticles are hard to produce. Here we report on poly (acrylonitrile) (PAN) composite nanofiber mats, electrospun by a needle-based system, containing 50 wt% magnetite nanoparticles overall or in the shell of core–shell fibers, collected on a flat or a rotating collector. While the first nanofiber mats show an irregular morphology, the latter are quite regular and contain straight fibers without many beads or agglomerations. Scanning electron microscopy (SEM) and atomic force microsc...

World Academy of Science, Engineering and Technology International Journal of Electrical and Computer Engineering, 2019

Electrospinning is the most widely utilized method to create nanofibers because of the direct setup, the capacity to mass-deliver consistent nanofibers from different polymers, and the ability to produce ultrathin fibers with controllable diameters. Smooth and much arranged ultrafine Polyacrylonitrile (PAN) nanofibers with diameters going from submicron to nanometer were delivered utilizing Electrospinning technique. PAN powder was used as a precursor to prepare the solution utilized as a part of this process. At the point when the electrostatic repulsion contradicted surface tension, a charged stream of polymer solution was shot out from the head of the spinneret and along these lines ultrathin nonwoven fibers were created. The effect of electrospinning parameter such as applied voltage, feed rate, concentration of polymer solution and tip to collector distance on the morphology of electrospun PAN nanofibers were investigated. The nanofibers were heat treated for carbonization to examine the changes in properties and composition to make for electrical application. Scanning Electron Microscopy (SEM) was performed before and after carbonization to study electrical conductivity and morphological characterization. The SEM images have shown the uniform fiber diameter and no beads formation. The average diameter of the PAN fiber observed 365nm and 280nm for flat plat and rotating drum collector respectively. The four probe strategy was utilized to inspect the electrical conductivity of the nanofibers and the electrical conductivity is significantly improved with increase in oxidation temperature exposed.

Journal of emerging technologies and innovative research, 2020

Electrospinning is a very simple process for producing nanofibers from any polymer solution via high-electric voltage. It utilizes electric forces and hence the electrical properties of the solution are affected. It has been recognized an effective method for the manufacturing of nanofibers. In recent years nanofibers have been successfully produced by electrospinning using various polymers. Polyacrylonitrile (PAN) nanofibers have unique properties like large surface area to volume ratio, mechanical strength, and flexibility so they can be used in various applications. PAN solution has rich contents of carbon so it is mostly used for synthesis of Carbon nanofibers. This paper reports the synthesis of PAN nanofibers, their diameter and surface morphology.

Journal of Dispersion Science and Technology, 2014

Magnetic nanofibers were fabricated using polyvinyl alcohol as a shelter for magnetic nanoparticles suspension. The transformation process from ferrofluid and polyvinyl alcohol solution to magnetic nanofibers has been investigated where the response variable analyzed was morphology. The results obtained from the high resolution transmission electron microscopy observation revealed that the flow rate and voltage have significant effect on desirable morphology. Nanofibers with fancy morphology and better aligned order tend to have higher elasticity contributed by the better alignment of lamellae along the fibers axis and molecular orientation. The fabricated nanofibers were ultra-fine with nanosize diameter within the range of approximately 290-380 nm.

2008

Polymer-stabilized magnetic nanoparticles were obtained using two biocompatible polyelectrolytes: N-carboxyethylchitosan (CECh) and poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS). The size of the particles (mean diameter 10 or 30 nm, respectively) and the stability of the dispersions could be effectively controlled depending on the polyelectrolyte nature. The presence of polyelectrolyte shell was proved by transmission electron microscopy (TEM) studies and confirmed by thermogravimetric analyses. Depending on the polyelectrolyte nature the magnetic nanoparticles existed in different magnetic states -superparamagnetic or intermediate state between superparamagnetic and ferrimagnetic one, as evidenced by the measurements of the magnetization and Mö ssbauer analyses. Fabrication of nanocomposite magnetic fibers with mean diameter in the range 100-500 nm was achieved using electrospinning of the system CECh/ferrofluid/nonionogenic polymer.

IOP Conference Series: Materials Science and Engineering

This paper reports the nanostructural and magnetic behaviors of nano-sized magnetite/polyvinyl alcohol prepared by electrospinning route. The composition of the magnetite nanoparticles and polyvinyl alcohol were prepared from natural iron sand. The samples were maintained for pure magnetite without fibers, 0.075 g and 0.175 g for the mass compositions of magnetite in the fibers. The experimental data presented that the mass variation of the magnetite decreased the diameter of the fibers. Moreover, the higher composition of the magnetite has led to an increase in the saturation magnetization of the fibers. Such results were confirmed by the increasing content of the Fe atoms originating from magnetite particles. Morphologically, the magnetite/polyvinyl alcohol fibers were formed in continuous fibers with the diameter of 300 nm for optimum voltage of 20 kV.

In this study, the effects of different dopants such as camphorsulfonic acid (CSA), dodecylbenzene sulfonic acid sodium salt (DBSANa +), different solvents such as N,N'-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO) and different mixing processes such as magnetic mixing and mechanical mixing on the morphology, conductivity and mechanical properties of PAN/PANi composite nanofibers are investigated. It has been seen that composite nanofibers had the smallest fiber diameter, lowest conductivity and lowest mechanical properties when CSA (dopant) and DMF (solvent) are used. However, the composite nanofibers in which the polyaniline is doped with CSA in DMSO (solvent) had better conductivity and mechanical properties, besides having thicker diameters. When the mixing effects compared, mechanical mixing process resulted in higher mechanical properties of nanofibers compared to magnetic mixing process, while there was not much difference between fiber diameter and conductivity values.

Journal of Nanoparticle Research, 2010

We describe a simple method based on the electrospinning process to prepare heterogeneous hybrid submicronic fibers with magnetic behavior, consisting of Co nanoparticles embedded in a polyacrylonitrile (PAN) polymer. Quantity and anisotropy of magnetic nanoparticles are key parameters to improve the specific magnetic properties of fibers. We notably show that for higher Co nanoparticles concentration, their lower dispersity into the resulting fibers lead to dipolar interactions that become demagnetizing. The structural and morphological properties of Co nanodisks and of the resulting nanocomposite fibers are investigated by SEM, TEM, and EDX. The magnetic properties of the hybrid electrospun fibers have been evaluated with a SQUID magnetometer.

Journal of applied polymer science, 2006

Polyacrylonitrile (PAN) was electrospun in dimethylformamide as a function of electric field, solution flow rate, and polymer concentration (C). The fiber diameter increased with C and ranged from 30 nm to 3.0 mm. The fiber diameter increased with the flow rate and decreased when the electric field was increased by a change in the working distance; however, it did not change significantly when the electric field was varied by a change in the voltage at a given working distance. The fibers below about 350 nm diameter contained beads, whereas above this diameter, bead-free fibers were obtained. For PAN with a molecular weight of 100,000 g/mol, the fiber diameter scaled as C 1.2 and C 7.5 at low (5.1-16.1 wt %) and high (17.5-22.1 wt %) C values, respectively. Both concentrations were in the semidilute entangled regime, where the specific viscosity scaled as C 4.4 , consistent with De Gennes's scaling concepts. In the semidilute unentangled regime (0.5-3.1 wt %), where the viscosity scaled as C 1.3 , microscopic or nanoscopic particles rather than fibers were obtained. Concentrationdependent electrospinning studies were also carried out for higher molecular weight PAN (250,000 and 700,00 g/mol). The results of these studies are also presented and discussed.

Materials

Magnetic nanofibers are of great interest in basic research, as well as for possible applications in spintronics and neuromorphic computing. Here we report on the preparation of magnetic nanofiber mats by electrospinning polyacrylonitrile (PAN)/nanoparticle solutions, creating a network of arbitrarily oriented nanofibers with a high aspect ratio. Since PAN is a typical precursor for carbon, the magnetic nanofiber mats were stabilized and carbonized after electrospinning. The magnetic properties of nanofiber mats containing magnetite or nickel ferrite nanoparticles were found to depend on the nanoparticle diameters and the potential after-treatment, as compared with raw nanofiber mats. Micromagnetic simulations underlined the different properties of both magnetic materials. Atomic force microscopy and scanning electron microscopy images revealed nearly unchanged morphologies after stabilization without mechanical fixation, which is in strong contrast to pure PAN nanofiber mats. While...

Journal of Materials Science, 2010

In this work, we report our attempt on the production of well-aligned nanofibers of poly (ethylene oxide) (PEO) by the introduction of magnetic field in the electric field by placing a cylindrical magnet within the electric field. Well-aligned nanofibers were obtained on top of the magnet. No particular structure could be associated with the other sides of the magnet. The aligned nanofibers were characterized by a host of characterization techniques such as optical and scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The diameter of the PEO nanofibers ranged between 500 and 1000 nm.

Magnetochemistry

Electrospun magnetic nanofibers are promising for a variety of applications in biomedicine, energy storage, filtration or spintronics. The surface morphology of nanofiber mats plays an important role for defined application areas. In addition, the distribution of magnetic particles in nanofibers exerts an influence on the final properties of nanofiber mats. A simple method for the production of magnetic nanofiber mats by the addition of magnetic nanoparticles in an electrospinning polymer solution was used in this study. In this work, magnetic nanofibers (MNFs) were prepared by needle-free electrospinning technique from poly(acrylonitrile) (PAN) in the low-toxic solvent dimethy lsulfoxide (DMSO) and 20 wt% Fe3O4 at different parameter conditions such as PAN concentration, voltage and ultrasonic bath. The distribution of nanoparticles in the fiber matrix was investigated as well as the chemical and morphological properties of the resulting magnetic nanofibers. In addition, the surfac...

Environmental Science: Nano, 2016

Novel nanocomposite sorbents of superparamagnetic iron oxide nanoparticles (SPION) supported onto electrospun polyacrylonitrile nanofibers were synthesized by a simple and scalable method.

Journal of Applied Physics, 2010

This work involved the preparation of nanoparticles for Fe 3 O 4 oxides with NiCl 2 and V 2 O 5 SO 4 by using ferric chloride as a mineral salt. X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electronic microscopy (SEM), field emission scanning electronic microscopy, Fourier transform infrared spectroscopy, thermogravimetry analysis and differential scanning calorimetric (DSC) analysis were performed. The efficiencies of NiO and V 2 O 5 were measured for gas sensitivity and light detection, which were high in both analyses. AFM tests showed that different nanoparticles formed similar acrylate polymers to NiO and V 2 O 5 with the diameters ranging from 72.12 to 88.12 nm. The XRD measurements showed the hexagonal shape of NiO, while the axon axes were observed for V 2 O 5 in SEM measurements. The image measurements showed different forms of polymer compositions. Moreover, the thermodynamic analysis indicated a thermal dissolution for both polymers and oxides prepared at extremely high temperatures. Finally, DSC tests identified the effect of polymer filled with oxide and its comparison with pure polymer.

Journal of Composite Materials, 2017

Electrically conductive and magnetically permeable carbon nanofiber-based composites were developed using the electrospinning with subsequent heat treatment. The composite nanofiber contains a variable composition of magnetite nanoparticles with two different size regimes, ranging from superparamagnetic (10–20 nm) to ferromagnetic (20–30 nm). The composite nanofibers are then characterized using Scanning/Transmission Electron Microscopy, X-Ray Diffractometry, Raman Spectroscopy, four-point probe, and a Superconducting Quantum Interference Device. Electromagnetic Interference Shielding Effectiveness of pristine carbon nanofibers as well as electromagnetic composite nanofibers are examined in the X-band frequency region. Higher degree of graphitization, electrical conductivity, and magnetic strength are obtained for nanocomposites containing larger magnetite nanoparticles (20–30 nm). A transition from superpartamagnetic to ferromagnetic characteristics is observed during nanocomposite...