Single-nozzle Electrospinning Technique Research Articles

A novel one-dimensional Y2(Zr0.6Ti0.4)2O7:Eu tube-in-tube nanostructure fabricated by a single-nozzle electrospinning technique and its low color drift property at high temperature

1D Y2(Zr0.6Ti0.4)2O7:Eu tube-in-tube nanostructures were fabricated by a simple single-nozzle electrospinning method. These materials exhibit excellent luminescent stability and lower color drift performance at high temperatures.

Conductive, Acid-Doped Polyaniline Electrospun Nanofiber Gas Sensing Substrates Made Using a Facile Dissolution Method.

A novel dissolution method that allows for the total solvation of high-concentration, high-molecular-weight polyaniline (PANi) doped with (+)-camphor-10-sulfonic acid (CSA) is reported. Preparation of 12-16 wt % 65,000 Da PANi solutions in N,N-dimethylformamide is achievable using a simple one-pot method. Doped polyaniline solutions in common organic solvents were processed into nanofibers using a convenient single-nozzle electrospinning technique. The electrospinning of PANi-CSA into nanofibrous membranes generated substrates that were subsequently employed in colorimetric gas sensing. These substrates demonstrated linearity of response upon exposure to 50-5500 ppm ammonia at ambient (50 ± 10% RH) and high (80% RH) humidity.

Construction of IrO2@Mn3O4 core-shell heterostructured nanocomposites for high performance symmetric supercapacitor device

In the present work, we have designed and synthesized nanocomposite of IrO2@Mn3O4 with two-step simple and scalable chemical routes. In this route, nanofibers of IrO2 were synthesized by a single nozzle electrospinning technique onto which Mn3O4 was overlaid by a simple SILAR route. The ratio of Mn3O4 and IrO2 was varied by varying the SILAR cycles onto electrospun IrO2 thin film as 20, 40, 60, and 80 cycles. The structural, morphological, and energy storage performance of IrO2@Mn3O4 composite electrodes were investigated. A 2 V kinetic potential with a rectangular-shaped cyclic voltammogram was observed for the IrO2@Mn3O4 electrodes. Moreover, the specific capacitance of 1027 F/g at 1 mA/cm2 was observed for the optimized electrode which is superior as compared with other electrodes. The optimized electrode showed better current and voltage than the individual compounds which might be due to the synergic effect of IrO2 and Mn3O4. Finally, a PVA-LiClO4 gel electrolyte-based solid-state IrO2@Mn3O4//IrO2@Mn3O4 symmetric device was fabricated. The symmetric device possessed an energy density of 81 Wh/kg with a power delivery of 714 W/kg which was capable to light up a green LED. Hence, the 2D transition metal oxides laminated on 1D metal oxides with high conductivity can be promising electrodes for future research.

MgO Nanoparticles-Incorporated PCL/Gelatin-Derived Coaxial Electrospinning Nanocellulose Membranes for Periodontal Tissue Regeneration.

Electrospinning technique has attracted considerable attention in fabrication of cellulose nanofibrils or nanocellulose membranes, in which polycaprolactone (PCL) could be used as a promising precursor to prepare various cellulose nanofibril membranes for periodontal tissue regeneration. Conventional bio-membranes and cellulose films used in guided tissue regeneration (GTR) can prevent the downgrowth of epithelial cells, fibroblasts, and connective tissue in the area of tooth root but have limitations related to osteogenic and antimicrobial properties. Cellulose nanofibrils can be used as an ideal drug delivery material to encapsulate and carry some drugs. In this study, magnesium oxide (MgO) nanoparticles-incorporated PCL/gelatin core-shell nanocellulose periodontal membranes were fabricated using coaxial electrospinning technique, which was termed as Coaxial-MgO. The membranes using single-nozzle electrospinning technique, namely Blending-MgO and Blending-Blank, were used as control. The morphology and physicochemical property of these nanocellulose membranes were characterized by scanning electron microscopy (SEM), energy-dispersive spectrum of X-ray (EDS), transmission electron microscopy (TEM), contact angle, and thermogravimetric analysis (TGA). The results showed that the incorporation of MgO nanoparticles barely affected the morphology and mechanical property of nanocellulose membranes. Coaxial-MgO with core-shell fiber structure had better hydrophilic property and sustainable release of magnesium ion (Mg2+). CCK-8 cell proliferation and EdU staining demonstrated that Coaxial-MgO membranes showed better human periodontal ligament stem cells (hPDLSCs) proliferation rates compared with the other group due to its gelatin shell with great biocompatibility and hydrophilicity. SEM and immunofluorescence assay results illustrated that the Coaxial-MgO scaffold significantly enhanced hPDLSCs adhesion. In vitro osteogenic and antibacterial properties showed that Coaxial-MgO membrane enhanced alkaline phosphatase (ALP) activity, formation of mineralized nodules, osteogenic-related genes [ALP, collagen type 1 (COL1), runt-related transcription factor 2 (Runx2)], and high antibacterial properties toward Escherichia coli (E. coli) and Actinobacillus actinomycetemcomitans (A. a) when compared with controls. Our findings suggested that MgO nanoparticles-incorporated coaxial electrospinning PCL-derived nanocellulose periodontal membranes might have great prospects for periodontal tissue regeneration.

Development and characterization of 5-fluorouracil nanofibrous film for the treatment of stomach cancer

The purpose of the present exposition was to develop 5-fluorouracil (5-FU) loaded gastro retentive nanofibrous film, to improve the chemotherapeutic performance in gastric cancer. 5-FU loaded Eudragit S-100 composite nanofibers have been prepared and optimized using a single nozzle electrospinning technique. The prepared nanofibers were evaluated for inclusive pharmaceutical aspects including drug encapsulation, physical properties, surface morphology, buoyancy, tensile strength, thermal properties, and in-vitro release. The developed formulation shows high % drug encapsulation (>90%), superior thermal stability, and released 90% of encapsulated therapeutic after 12 h. The optimized formulation was subjected to in-vivo antitumor performance against Ehrlich Ascites Carcinoma (EAC) induced orthotopic xenograft models. The developed nanofiber formulation exhibits superior tumor regression potential and pharmacokinetic profile compared to the plain drug. Experimental findings suggest that a nanofiber-based gastro retentive drug delivery system offers a potential strategy for the localized treatment of gastric cancer with improved chemotherapeutic performance.

Pt nanoparticles supported on a novel electrospun polyvinyl alcohol-CuO[sbnd]Co3O4/chitosan based on Sesbania sesban plant as an electrocatalyst for direct methanol fuel cells

Here, novel polyvinyl alcohol (PVA) nanofibers with incorporated CuO and Co3O4 nanoparticles (PVA-CuOCo3O4) were synthesized through a conventional single-nozzle electrospinning technique and characterized by atomic force microscopy (AFM), energy dispersive X-ray analysis (EDX), fourier-transform infrared spectroscopy (FT-IR), elemental analysis, transmission electron microscopy (TEM), differential thermal analysis (DTA), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Novel Pt/polyvinyl alcohol-CuOCo3O4/chitosan (Pt/PVA-CuOCo3O4/CH) catalyst was successfully prepared. EDX, TEM, and FT-IR spectroscopy techniques were used to characterize the prepared catalysts. The electrocatalytic activity of Pt/PVA-CuOCo3O4/CH catalyst was investigated for methanol electrooxidation through cyclic voltammetry, chronoamperometry, CO stripping voltammetry, and electrochemical impedance spectroscopy techniques. The effects of some experimental factors for methanol electrooxidation were studied on the prepared catalysts and the optimum conditions were determined. Pt/PVA-CuOCo3O4/CH catalyst had extraordinary electrocatalytic activity for methanol electrooxidation. It exhibited better stability, higher electrochemically active surface area, and better antipoisoning effect than Pt/PVA-CuOCo3O4 and Pt/PVA/CH catalysts indicating that Pt/PVA-CuOCo3O4/CH could be a promising catalyst for direct methanol fuel cell (DMFC) applications. A real DMFC was designed, assembled and tested with Pt/PVA-CuOCo3O4/CH as anodic catalyst.

Electrospun nanofiber composites with micro-/nano-particles for thermal insulation

Polyacrylonitrile (PAN) nanofiber and silica aerogel (SAG) laminated composites were prepared via electrospinning for thermal insulation. Conventional single nozzle and co-axial electrospinning were used to increase the fraction of aerogel particles in the composite sheets while maintaining the mechanical strength of the sheet. When the core-shell electrospinning technique with co-axial nozzle was applied, the proportion of aerogel particles increased two fold without a deterioration of the mechanical properties. The average thermal conductivity of the laminated composite sheet was reduced by approximately 12.5% as compared to the nanofiber composite prepared using the single-nozzle electrospinning technique. For additional reduction in thermal conductivity, hollow glass microspheres (HGM) was inserted between the interlayer spacing of the electrospun sheets to increase the interlayer spacing. When HGM particles were inserted, it was observed that the thermal conductivity decreased by approximately 20% compared to that of the specimen without particles.

Facile synthesis of one-dimensional mesoporous cobalt ferrite nanofibers for high lithium storage anode material

One-dimension mesoporous cobalt ferrite (CoFe2O4) nanofibers were prepared by a facile single-nozzle electrospinning technique followed by calcination. The lithium storage properties show that the CoFe2O4 nanofibers obtained at 800 °C deliver an initial discharge capacity of 1888 mAh g−1 and a reversible capacity as high as 942 mAh g−1 after 80 cycles, much higher than those of the samples obtained at 600 °C (1193 and 701 mAh g−1, respectively). The CoFe2O4 nanofibers obtained at 800 °C also demonstrate an excellent rate capability. The improved lithium storage properties of CoFe2O4 nanofibers obtained at 800 °C can be attributed to the unique mesoporous and fibrous structures, as well as the high crystallinity, which provide an easy Li+ diffusion path promote electron transfer, meanwhile preventing volume expansion/contraction during discharge/charge processes.

NiFe₂O₄ Nanofibers: Morphology, Lithium Storage and Photocatalytic Properties.

One dimensional (1D) NiFe2O4 nanofibers have been successfully fabricated using single-nozzle electrospinning technique and subsequent calcination process through adjusting heat-treatment parameters. The calcination procedure plays a key role for the formation of nanofibers with different morphologies. The lithium storage properties of NiFe2O4 nanofibers were evaluated by galvanostatic cycling studies in half-cell configuration. Furthermore, their photocatalytic property under vis-light irradiation with H2O2 addition is investigated at room temperature. As-synthesized nanofibers with regular 1D nanostructure with large surface area and high crystallinity calcined at 600 °C exhibited fine lithium storage with excellent cycling and rate performance, as well as excellent photocatalytic performance with 97% degradation proportion of methylene blue after 30 min. This is ascribed to NiFe2O4 absorbed the photon energy and generated electron-hole pairs under vis-light irradiation.

Electrospun NiFe2O4@C fibers as high-performance anode for lithium-ion batteries

NiFe2O4 nanoparticles (about 18nm) homogeneously encapsulated in porous carbon fibers (denoted as NFO@C) were successfully fabricated using single-nozzle electrospinning technique with subsequent two-step calcination process. The formation of inverse spinel-type NiFe2O4 was determined by X-ray diffraction patterns. Stable fibrous NFO@C with average diameter of 400nm exhibited large surface area and porous structure. Moreover, as anode materials for lithium-ion batteries (LIBs), NFO@C fibers electrode exhibited excellent cycling performance (497mAhg−1 after 100cycles at 100mAg−1) and excellent rate performance compared with NFO fibers electrode. This is owing to the special structure of small NiFe2O4 nanoparticles embedded in porous carbon fibers, which effectively improve the electrical conductivity of the electrodes, decrease the diffusion path of Li+ ions, as well as prevent the particle pulverization/agglomeration during cycling. Thus, this work paves a potential pathway for designing efficient transition metal oxides-based LIBs anode materials by the combination of carbon matrix.

Facile fabrication of coaxial-cable like Mn2O3 nanofiber by electrospinning: Application as electrode material for supercapacitor

Coaxial-cable like Mn2O3 nanofibers are fabricated by a facile and cost-effective single-nozzle electrospinning technique and subsequent calcination. The morphology, microstructure, crystal structure, composition and specific surface area are characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and N2 adsorption–desorption. A possible formation mechanism of the coaxial-cable like Mn2O3 nanofiber has also been proposed. Due to the large specific surface area and porous structure, the synthesized coaxial-cable like Mn2O3 nanofiber is employed as the electrode for supercapacitor in 6M KOH aqueous condition. The specific capacitance is up to 216F/g at 0.5A/g and the electrode also exhibited excellent cycling stability of 93% capacitance retention after 1000 cycles. The encouraging results show the potential of the coaxial-cable like Mn2O3 nanofiber as supercapacitor electrode material.

Fe3O4 nanoparticles encapsulated in electrospun porous carbon fibers with a compact shell as high-performance anode for lithium ion batteries

Fe3O4 nanoparticles encapsulated in porous carbon fibers (Fe3O4@PCFs) as anode materials in lithium ion batteries are fabricated by a facile single-nozzle electrospinning technique followed by heat treatment. A mixed solution of polyacrylonitrile (PAN) and polystyrene (PS) containing Fe3O4 nanoparticles is utilized to prepare hybrid precursor fibers of Fe3O4@PS/PAN. The resulted porous Fe3O4/carbon hybrid fibers composed of compact carbon shell and Fe3O4-embeded honeycomb-like carbon core are formed due to the thermal decomposition of PS and PAN. The Fe3O4@PCF composite demonstrates an initial reversible capacity of 1015mAhg−1 with 84.4% capacity retention after 80 cycles at a current density of 0.2Ag−1. This electrode also exhibits superior rate capability with current density increasing from 0.1 to 2.0Ag−1, and capacity retention of 91% after 200 cycles at 2.0Ag−1. The exceptionally high performances are attributed to the high electric conductivity and structural stability of the porous carbon fibers with unique structure, which not only buffers the volume change of Fe3O4 with the internal space, but also acts as high-efficient transport pathways for ions and electrons. Furthermore, the compact carbon shell can promote the formation of stable solid electrolyte interphase on the fiber surface.

Porous Ni nanofibers with enhanced catalytic effect on the hydrogen storage performance of MgH2

Porous Ni nanofibers (NFs) were synthesized via a single-nozzle electrospinning technique with subsequent calcination and reduction.

Hierarchical porous Li₂Mg(NH)₂@C nanowires with long cycle life towards stable hydrogen storage.

The hierarchical porous Li2Mg(NH)2@C nanowires full of micropores, mesopores, and macropores are successfully fabricated via a single-nozzle electrospinning technique combined with in-situ reaction between the precursors, i.e., MgCl2 and LiN3, under physical restriction upon thermal annealing. The explosive decomposition of LiN3 well dispersed in the electrospun nanowires during carbothermal treatment induces a highly porous structure, which provides a favourable way for H2 delivering in and out of Li2Mg(NH)2 nanoparticles simultaneously realized by the space-confinement of the porous carbon coating. As a result, the thus-fabricated Li2Mg(NH)2@C nanowires present significantly enhanced thermodynamics and kinetics towards hydrogen storage performance, e.g., a complete cycle of H2 uptake and release with a capacity close to the theoretical value at a temperature as low as 105°C. This is, to the best of our knowledge, the lowest cycling temperature reported to date. More interestingly, induced by the nanosize effects and space-confinement function of porous carbon coating, a excellently stable regeneration without apparent degradation after 20 de-/re-hydrogenation cycles at a temperature as low as 130°C was achieved for the as-prepared Li2Mg(NH)2@C nanowires.

Hollow SnO2-ZnO hybrid nanofibers as anode materials for lithium-ion battery

Hollow SnO2–ZnO hybrid nanofibers are prepared by a single-nozzle electrospinning technique followed with subsequent heat treatment. The structure and morphology of the samples are characterized by x-ray diffraction, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy and transmission electron microscopy. The as-prepared nanofibers are solid, which maintain after annealing up to 400 °C; while they turn to tubular morphology after annealing at 500 °C. After annealing at 700–900 °C, some of the tubular nanofibers combine together. The FTIR results show that poly (vinylpyrrolidone) is completely removed after annealing at 500 °C. The electrode of hollow SnO2–ZnO nanofibers obtained by calcination at 500 °C delivers a high discharge capacity of 546.5 mAh g−1 after 100 cycles at a current density of 100 mA g−1.

Sb–C nanofibers with long cycle life as an anode material for high-performance sodium-ion batteries

Sb–C nanofibers are synthesized successfully through a single-nozzle electrospinning technique and subsequent calcination. The structural and morphological characterizations reveal the uniform nanofiber structure with the Sb nanoparticles embedded homogeneously in the carbon nanofibers. Electrochemical experiments show that the Sb–C nanofiber electrode can deliver large reversible capacity (631 mA h g−1) at C/15, greatly improved rate capability (337 mA h g−1 at 5 C) and excellent cycling stability (90% capacity retention after 400 cycles). The superior electrochemical performances of the Sb–C nanofibers are due to the unique nanofiber structure and uniform distribution of Sb nanoparticles in carbon matrix, which provides a conductive and buffering matrix for effective release of mechanical stress caused by Na ion insertion/extraction and prevent the aggregation of the Sb nanoparticles.

Electrospinning La0.8Sr0.2Co0.2Fe0.8O3−δ tubes impregnated with Ce0.8Gd0.2O1.9 nanoparticles for an intermediate temperature solid oxide fuel cell cathode

In order to reduce the polarization resistance of the cathode, we have developed one-dimensional (1D) nanostructured La0.8Sr0.2Co0.2Fe0.8O3−δ (LSCF) tubes/Ce0.8Gd0.2O1.9 (GDC) nanoparticles composite cathodes for solid oxide fuel cell. Uniform LSCF/PVP composite nanofibers have been firstly synthesized by a single-nozzle electrospinning technique, followed by firing at 800 °C for 2 h to form one-dimensional LSCF tubes. Subsequently, the GDC phases were introduced into tube structured LSCF scaffold pre-sintered on a GDC pellet by a multi-impregnation process. Electrochemical Impedance spectra reveal that nanostructured LSCF tubes/GDC nanoparticles composite cathodes have a better electrochemical performance, achieving area-specific resistances of 4.70, 1.12, 0.27 and 0.07 Ω cm2 at 500, 550, 600 and 650 °C for the composite of GDC and LSCF in a weight ratio of 0.52:1. The low ASR values are mainly related to its optimal microstructure with larger triple-phase boundaries and higher porosity. These results suggest that LSCF tube/GDC nanoparticle composite can be an alternative cathode material for intermediate temperature solid oxide fuel cell (IT-SOFC).

Synthesis, characterization, and lithium-storage of ZnO–SnO2 hierarchical architectures

Hierarchical ZnO–SnO2 composite nanofibers have been prepared through the single-nozzle electrospinning technique and subsequent calcinations using polyvinyl pyrrolidone as the fiber template and N,N-dimethylformamide as the solvent. The structures and morphologies of the samples were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. The mesoporous nanofibers are composed of homogeneous grain-like nanoparticles, and heterostructures are formed between ZnO and SnO2. When used as the anode of lithium ion batteries, the ZnO–SnO2 composite nanofibers show first discharge and charge capacities of 1795 and 1364 mA h g−1 at a current density of 50 mA g−1. A reversible capacity of 588 mA h g−1 is obtained after 100 cycles. The ZnO–SnO2 composite nanofibers prepared by such a simple and cheap method are expected to have a potential application in energy storage.

Single electrospun porous NiO–ZnO hybrid nanofibers as anode materials for advanced lithium-ion batteries

Porous NiO-ZnO hybrid nanofibers were prepared by a single-nozzle electrospinning technique combined with subsequent heating treatment. The resultant nanofibers are composed of interconnected primary nanocrystals and numerous nanopores with heterostructures between NiO and ZnO. Such characteristics of the structure can lead to excellent electrochemical performances when the nanofiber was evaluated as an anode material for lithium-ion batteries. The porous NiO-ZnO nanofiber electrode delivers a high discharge capacity of 949 mA h g(-1) after 120 cycles at 0.2 A g(-1), and maintains around 707 mA h g(-1) at a current density as high as 3.2 A g(-1). Even after cycling at high rates, the electrode still retains a high discharge capacity of up to 1185 mA h g(-1) at 0.2 A g(-1).

Controllable fabrication and broadband near-infrared luminescence of various Ni2+-activated ZnAl2O4 nanostructures by a single-nozzle electrospinning technique

By finely tuning the electrospun parameters (feeding rate of solution, working voltage and distance, etc.) and concentration of inorganic salts, various ZnAl(2)O(4) nanostructures (nanoparticles, nanonecklaces, nanofibers, nanotubes and hollow micromelts) were controllably synthesized by a single-nozzle electrospinning technique. The formation mechanisms of different ZnAl(2)O(4) nanostructures, including 'oriented attachment' mechanism, 'gas-push' mechanism, etc., were proposed to elucidate the morphology of the nanostructures and microstructure evolvement process. The morphology and microstructure of calcined electrospun nanostructures were considered to be mainly dependent on two factors, i.e. concentration of inorganic salts and size of as-prepared electrospun nanofibers. Using Ni(2+) ions as activators, broadband near infrared (NIR) emission covering 1000-1400 nm peaking at about 1176 nm was detected in Ni(2+)-doped ZnAl(2)O(4) nanostructures. The broadband NIR emission at around 1.3 μm optical communication window with a long lifetime of ~640 μs makes Ni(2+)-doped ZnAl(2)O(4) nanostructures as a promising candidate for micro/nano-broadband optical amplifiers, fibers, etc.