- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Handbook of Nanofibers || Mixed Metal and Metal Oxide Nanofibers: Preparation, Fabrication, and Applications
摘要： The review presents the overview of the design, synthesis, fabrication, and applications of metal and metal oxide-based nano?bers. Furthermore, it also describe the recent trends in methodologies used and types of nano?bers produced; including polymers, nanoparticles and ionic liquid based nano?bers. The great deal of interest and attention is currently being focused by the scienti?c community on nano- and mesostructured materials. The quest for the establishment of these classes of nanosystems has created new challenges in their research development processes. Nano?bers are ?bers with the size of around 100 nm, which are made from various inorganic materials such as ceramics, metal, and metal oxides. This review describes the synthesis, fabrication, and some of the selected applications of nano?bers in recent years. Mixed metals and their oxides give rise to a signi?cant class of nano?bers with fascinating properties. The metals and metal oxides which are used for the synthesis of nano?bers are, inter alia, Si, Ba, Ti, Mn, Cu, Fe, Sn, Sb, Ni, Mo, CeO2, TiO2, CuO, Fe2O3, MnO2, SnO2, and NiCo2O4. Generally, the important parameters such as morphology, size distribution, and composition in homogeneous systems are dif?cult to control, and, in the fabrication of new materials, the nanometer size of the dimensions should be maintained within the accepted ranges. Presently, microscale hierarchically structured nanomaterial-based nano?bers are focused and developed toward future technology. Moreover, the increasing prominence and signi?cance of the nano?ber industry are, in recent years, due to the heightened awareness of their capability to improve the performance of different forms of ?lter media. In addition, nano?bers have fascinating properties and advantages such as high surface area, small pore size, and high pore volume, over conventional ?bers. Generally, nano?bers are applied in various ?elds such as wound dressings, ?ltration and cleaning processes, tissue engineering scaffolds, drug release materials, energy storage, environmental engineering, defense, and security systems.
关键词： Electrospinning,Nano?ber,Force spinning,Metal oxide,Fabrications
更新于2025-09-23 15:21:21
-
Unexpectedly High Piezoelectricity of Electrospun Polyacrylonitrile Nanofiber Membranes
摘要： Polyvinylidene fluoride (PVDF) and its co-polymers are among the best piezoelectric polymer materials owing to the large piezoelectric coefficient and mechanical properties. Processing PVDF polymers into fibrous membranes through electrospinning can largely increase the piezoelectricity. In contrast, polyacrylonitrile (PAN), an amorphous polymer, is known to have a much lower piezoelectricity than PVDF. Herein, we report an unusually-high piezoelectric feature of electrospun PAN nanofiber membranes. When a small piece of PAN nanofiber nonwoven membrane (e.g. 5 cm2) was subjected to compressive impact, it can generate up to 2.0 V of voltage, the electrical outputs of which are even higher than that of PVDF nanofiber membranes at the same condition. Such unexpected piezoelectric properties were found to originate from the high content of planar Sawtooth PAN conformation within nanofibers. Electric charges in PAN nanofibers also contributed to the energy conversion. The energy conversion capability can be further enhanced by increasing fiber orientation within fibrous membrane. Also, the working area and thickness of nanofibrous membranes as well as impact conditions influenced piezoelectric outputs. The energy generated is usable and can power commercial LEDs. These unexpected discovery may inspire to develop novel piezoelectric materials and devices.
关键词： polyacrylonitrile,Piezoelectric,electrospinning,nanofibers
更新于2025-09-23 15:21:21
-
Inorganic and Composite Fibers || Photocatalytic Properties of TiO2 Composite Nanofibers Electrospun With Different Polymers
摘要： Electrospinning offers the possibility to create fibers with very fine diameters. Spinning ultrafine fibers with diameters in the range of some hundred nanometers from melt or solution has been established some decades ago. With electrospinning, depending on the exact technology, either continuous fibers or fiber mats with relatively narrow diameter distributions can be created from a broad range of materials, starting from polymers to composites and even ceramics. Due to their large inner surface area, nanofiber mats are typically used as filter materials, catalyzers, medical wound dressing, or for promotion of cell growth in biomedical applications. Electrospinning ceramic nanofibers can be performed by co-spinning a blend of polymer and ceramic precursor, followed by calcination to remove the polymer matrix and keep only the ceramic fibers. Alternatively, ceramic nanoparticles can be bonded on the surfaces of polymer nanofibers, or hybrid nanofibers can be formed, consisting of ceramic and polymer materials. In this way, electrospinning can be used to produce a broad variety of nanofibers, besides other typical methods such as self-assembly, use of templates, or drawing, for applications in life sciences, energy storage, dye-sensitized solar cells (DSSCs), electronic and magnetic devices, bonding, etc.
关键词： TiO2 nanofibers,Electrospinning,photocatalytic properties,calcination,polymer composites
更新于2025-09-23 15:21:01
-
Ionic relaxation of electrospun nanocomposite polymer-blend quasi-solid electrolyte for high photovoltaic performance of Dye-sensitized solar cells
摘要： New quasi-solid electrolytes were developed by blending PVDF-HFP and PMMA with dispersed TiO2 nanoparticles as fillers and electrospun as, nanofibrous porous membranes activated in electrolyte solutions with various redox couples. Among them, PVDF-HFP/ PMMA 6 wt% TiO2 with LiI based redox electrolyte have achieved highest conductivity of 2.26 × 10?2 Scm-1 and power conversion efficiency (PCE) of 7.081% for its fabricated DSSC. The dynamics of the ionic transport of charge carriers of the developed electrolyte membranes were studied using Random barrier model. The relaxation mechanisms of ionic charge carriers were analysed by Havriliak–Negami formulation. It is inferred that the conductivity is dominated by electrode-polarization and ionic charges exhibit non-debye behaviour in conducting mechanism.
关键词： Electrolyte intake,Nanocomposite,Electrospinning,Relaxation
更新于2025-09-23 15:21:01
-
One-step hydrothermal synthesis of NiCo2S4 loaded on electrospun carbon nanofibers as an efficient counter electrode for dye-sensitized solar cells
摘要： Possing excellent catalytic performance about counter electrode (CE) is the prerequisite for obtaining high performance dye sensitized solar cells (DSSCs). Herein, The NiCo2S4/carbon nanofibers (NiCo2S4/CNFs) are successfully synthetised via hydrothermal and electrospinning method, and then directly used in DSSCs. Owing to the synergistic effect between the catalytic of NiCo2S4 materials and the electrical conductivity of CNFs, All chemical measurements reveal that NiCo2S4/CNFs applied in DSSCs exhibit good power conversion efficiency (9.0%) and stability, which surpass that of DSSCs with Pt CE (7.48%), indicating that NiCo2S4/CNFs composite would be helpful for the low-cost and efficient application of DSSCs.
关键词： Dye-sensitized solar cells,Electrospinning technology,Counter electrode,Transition metal sulfides
更新于2025-09-23 15:21:01
-
Efficient preparation of polymer nanofibers by needle roller electrospinning with low threshold voltage
摘要： A novel electrospinning system with needle roller as spinneret for efficient preparation of nanofibers was proposed. The results of finite element simulation indicate that the electric field is more concentrated at the tip of needle piece compared with that for disc and coil spinnerets, which can effectively reduce the threshold voltage of electrospinning. Using polyvinyl alcohol (PVA) as model polymer, the effects of spacing between needle pieces and concentration of spinning solution on fiber diameter and productivity of nanofibers were investigated. The results indicate that the average diameter decreases and the uniformity of diameter increases when increasing the spacing between needle pieces. When the spacing between the needle pieces is 14 mm, the average and standard deviation (SD) of fiber diameter is as small as 190 and 72 nm, respectively. The productivity of nanofibers slightly increases with the concentration of spinning solution, and it is as high as 12.8 g/h when the PVA concentration was 11 wt% for a needle piece spacing of 10 mm, which is much higher than the productivities of reported electrospinning systems. The proposed system has the potential for the preparation of uniform nanofibers with increased throughput and reduced cost.
关键词： electrospinning,productivity,nanofibers,needle roller,threshold voltage
更新于2025-09-23 15:21:01
-
Contents: (Adv. Funct. Mater. 44/2018)
摘要： Silica nanofibrous membranes produced by direct electrospinning of a sol-gel solution without a sacrificing polymer allow high-end separation and purification due to a high thermal and chemical resistance. The water repellent or absorbing nature can be tuned by applying a humidity or thermal treatment. It is showcased that fast gravity driven membrane separation of heterogeneous azeotropes can be achieved.
关键词： thermal resistance,chemical resistance,sol-gel,electrospinning,azeotrope separation,silica nanofibrous membranes
更新于2025-09-23 15:21:01
-
Dye-doped electrospun fibers for use as random laser generator: The influence of spot size and scatter concentration
摘要： The development of electrospun polymer fiber networks embedded with metal oxide nanoparticles in organic dye media favors the photons waveguiding and multiple scattering, providing the adequate environment for random laser action. The use of water-soluble polymer solution as support for electrospun matrix introduces relevant application in biomedical applications. Herein, it is explored the use of block copolymers (Eudragit L100) as support for electrospinning of polymer fiber doped with titanium dioxide (scatter centers) and rhodamine B (gain media). The resulting fiber net presented random laser behavior that depends on aggregation degree of gain media (rhodamine B) due to the combination of reabsorption/reemission processes with tunable response (emission peak position). These results open new possibilities for use of low-cost and water soluble electrospun-based random lasers based on organic dyes and random network of polymer matrix.
关键词： Fibers,Electrospinning,Organic dye,Random laser
更新于2025-09-23 15:19:57
-
A Novel Profiled Multi-Pin Electrospinning System for Nanofiber Production and Encapsulation of Nanoparticles into Nanofibers
摘要： Electrospinning with various machine configurations is being used to produce polymer nanofibers with different rates of output. The use of polymers with high viscosity and the encapsulation of nanoparticles for achieving functionalities are some of the limitations of the existing methods. A profiled multi-pin electrospinning (PMES) setup is demonstrated in this work that overcomes the limitations in the needle and needleless electrospinning like needle clogging, particle settling, and uncontrolled/uneven Taylor cone formation, the requirement of very high voltage and uncontrolled distribution of nanoparticles in nanofibers. The key feature of the current setup is the use of profiled pin arrangement that aids in the formation of spherical shape polymer droplet and hence ensures uniform Taylor cone formation throughout the fiber production process. With a 10 wt% of Polyvinyl Alcohol (PVA) polymer solution and at an applied voltage of 30 kV, the production rate was observed as 1.690 g/h and average fiber diameter obtained was 160.5 ± 48.9 nm for PVA and 124.9 ± 49.8 nm for Cellulose acetate (CA) respectively. Moreover, the setup also provides the added advantage of using high viscosity polymer solutions in electrospinning. This approach is expected to increase the range of multifunctional electrospun nanofiber applications.
关键词： Polymer,Nanoparticles,Electrospinning,Nanofibers,Encapsulation
更新于2025-09-23 15:19:57
-
One-step fabrication of 1D p-NiO nanowire/n-Si heterojunction: development of self-powered ultraviolet photodetector
摘要： Even though there are reports on NiO-p/Si-n based photodetector, work along 1D NiO/Si self-powered photodetector remains unexplored. 1D materials offer better electron mobility and can provide ballistic transport channel, which helps in achieving high responsivity. In this work, direct single-step deposition of p-type NiO nanowires on n-type Si as a self-powered photodetector was successfully fabricated by engaging simple electrospinning technique. The structural properties as observed from XRD indicate highly crystalline NiO nanowires and FESEM images revealed 60 ~75 nm diameter with uniform distribution. Growth of nanowires by using stimuli polymer and its completely removal at high temperature was confirmed using TGA and XPS analysis. The responsivity of the fabricated photodetector was calculated to be 9.1 mA W-1 at zero bias, which can be attributed to the p-type NiO interface with the n-type Silicon, which creates an internal electrical field thereby assisting in the effective separation of the photogenerated carriers. Further, under illumination, at zero bias, the photogenerated current still exists suggesting a generation of internal voltage, which makes the fabricated device as self-powered. This fabrication method will enhance the photodetection properties, and it can be implemented in the fields of optoelectronic devices, sensors, and flexible electronics.
关键词： Electrospinning,NiO nanowires,1D material,Self-powered photodetector
更新于2025-09-23 15:19:57