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Search for "fibers" in Full Text gives 182 result(s) in Beilstein Journal of Nanotechnology.
Ultralight super-hydrophobic carbon aerogels based on cellulose nanofibers/poly(vinyl alcohol)/graphene oxide (CNFs/PVA/GO) for highly effective oil–water separation
Beilstein J. Nanotechnol. 2018, 9, 508–519, doi:10.3762/bjnano.9.49
- history of using plant cellulose fibers as reinforcements in polymer composite materials [13][14]. However, the use of nanoscale cellulose fibers to reinforce polymers is a relatively recent effort [15][16]. Despite the challenges described below, CNFs have been combined with various polymer matrices
Engineering of oriented carbon nanotubes in composite materials
Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41
- due to their desirable physical properties [43]. In this regard, CNT/fibers have obtained a special spotlight because of their possibility to be arranged in a controlled way, the dependency of bulk electrical and mechanical properties of composites on the characteristics of the CNT, and the ensemble
- and production ability of the fibers in semi-industrial quantities [44]. The two methods commonly used to make CNT/nanofiber are described below. Electrospinning: Electrospinning (ES) can be used to produce fibers from a viscous solution of polymer/CNTs, it is also employed for aligning CNTs in the
- fibers. In this method, a high voltage DC current (about 25 kV) is used between a charged polymer and a metallic collector to produce continuous filaments. Experiments revealed that the functionalized CNTs are aligned in the direction of the axis of the nanofiber polymers [45][46][47]. Figure 7 shows a
Synthesis and characterization of electrospun molybdenum dioxide–carbon nanofibers as sulfur matrix additives for rechargeable lithium–sulfur battery applications
Beilstein J. Nanotechnol. 2018, 9, 262–270, doi:10.3762/bjnano.9.28
- precursors and self-templates, which were used as anode materials in lithium ion batteries [22][23]. However, since electrospinning is a simple and versatile method for producing fibers from a variety of materials on a large scale, it has attracted much attention in both research and commerce [24]. The
- electrochemical performance than a pristine sulfur cathode. Results and Discussion Characterization of MoO2–CNFs X-ray diffraction (XRD) patterns of the as-prepared composite fibers calcined at various temperatures are presented in Figure 1a. Well-defined features appeared for the samples heated at 550 °C due to
- MoO2–CNF was successfully prepared through electrospinning. The Fourier transform infrared spectroscopy (FTIR) spectra of PAN fibers, as-prepared composite PAN/PMA fibers, and composite fibers calcined at different temperatures are illustrated in Figure 2. The FTIR spectra of PAN fibers and as-prepared
Liquid-crystalline nanoarchitectures for tissue engineering
Beilstein J. Nanotechnol. 2018, 9, 205–215, doi:10.3762/bjnano.9.22
- alignment of ECM fibers is known to control the cell shape and motion [53]. During development, growth, and proliferation, the 2D/3D topography of ECM affects the cell spreading, focal adhesion strength, and intercellular mechanical signaling [54]. For example, the guided migration of cells in the ECM was
- shown to result in enhanced cellular reorganization and facilitated tissue morphogenesis [55]. Mechanical stiffness of tissues is an important physical cue for modulating the behavior of adhered or embedded cells [56][57]. The LC architectures of ECM fibers may influence the functionality of target
- structures [32]. Soft connective tissues Mesophase organizations of the ECM fibers can play important roles not only in the optimization of mechanical properties of the tissue itself, but also in the regulations of functions of embedded cells [65]. The assembly structure of oriented collagen fibers in
Bombyx mori silk/titania/gold hybrid materials for photocatalytic water splitting: combining renewable raw materials with clean fuels
Beilstein J. Nanotechnol. 2018, 9, 187–204, doi:10.3762/bjnano.9.21
- , Goutailler et al. deposited an anatase/brookite NP mixture on cellulose from tetrabutylammonium bromide (N(n-Bu)4Br)/titanium tetraisopropoxide (Ti(OiPr)4) solutions in hexane [32]. These NPs strongly interact via non-covalent interactions (e.g., hydrogen bonds [33][34]) with the cellulose fibers and the
- mechanically and chemically stable to withstand the conditions during photocatalysis. Daoud and Xin [35] coated cotton fibers with 20 nm anatase particles via a sol–gel method. The covalently bonded TiO2 particles have a 50+ UV protection factor and are stable against washing. In an alternative approach, Zheng
Electrical properties of a liquid crystal dispersed in an electrospun cellulose acetate network
Beilstein J. Nanotechnol. 2018, 9, 155–163, doi:10.3762/bjnano.9.18
- in a similar fashion as PDLCs (polymer-dispersed liquid crystals), produced from cellulose acetate (CA) electrospun fibers deposited onto indium tin oxide coated glass and a nematic liquid crystal (E7), were studied. CA and the CA/liquid crystal composite were characterized by multiple investigation
- the one observed in traditional PDLC. The major difference is that instead of having small droplets of LC confined in a polymeric matrix, the LC fills the voids between fibers in mats of non-woven electro-spun cellulose acetate fibers [21][22][23][24][25][26][27]. The electrospun cellulose fibers were
- . Results and Discussion Scanning electron microscopy Figure 2 shows the SEM image of the deposited fibers [21][22][28]. In the SEM image, the fibers exhibit a wide dimension range, starting with dozens of nanometres. Polarized optical microscopy Figure 3 presents the polarizing optical microscopy images of
Thermo- and electro-optical properties of photonic liquid crystal fibers doped with gold nanoparticles
Beilstein J. Nanotechnol. 2017, 8, 2790–2801, doi:10.3762/bjnano.8.278
- fibers (PCFs) infiltrated with a NP-doped nematic LC. PCFs infiltrated with LCs (Larsen et al. [15]) have been known since 2005 [16] as photonic liquid crystal fibers (PLCFs). PLCFs offer a high level of tunability due to significantly improved control of their spectral, polarizing, and guiding
- with two additional fibers on the sides with the same diameter as the measured fiber. These additional fibers were glued to one of two electrodes and they acted as spacers to maintain height control. There was a layer of silicon between the electrodes to prevent electric discharge that could destroy
- filled with 1 wt % Au-doped liquid crystal. Spectra up to the phase transition temperature (left) and magnification of the nematic–isotropic phase transition point (right). Rise time (a,b) and fall time (c,d) for 0.3 wt % Au and 1 wt % Au-doped photonic liquid crystal fibers compared to undoped LC 6CHBT
Dry adhesives from carbon nanofibers grown in an open ethanol flame
Beilstein J. Nanotechnol. 2017, 8, 2719–2728, doi:10.3762/bjnano.8.271
- linear with preload force. Carbon nanofibers oriented by a magnetic field show a 68% higher adhesion (0.66 N/cm2) than the randomly oriented fibers. Endurance tests revealed that the carbon nanofiber arrays withstand 50.000 attachment/detachment cycles without observable wear. Keywords: adhesion; atomic
One-step chemical vapor deposition synthesis and supercapacitor performance of nitrogen-doped porous carbon–carbon nanotube hybrids
Beilstein J. Nanotechnol. 2017, 8, 2669–2679, doi:10.3762/bjnano.8.267
- (CNTs) or fibers in an electrode material [4][5]. A typical synthesis procedure for carbon–carbon hybrid materials includes the mechanical mixing of the components, previously synthesized separately by different methods (ex situ synthesis). The mixing is usually carried out in a solvent, but since
Localized growth of carbon nanotubes via lithographic fabrication of metallic deposits
Beilstein J. Nanotechnol. 2017, 8, 2592–2605, doi:10.3762/bjnano.8.260
- obviously lifted-up by the CNT growth process. On top of the lifted square structure only very few CNTs with reduced length are observed. It is important to note that the diameter of CNTs in Figure 7b is a bit large. We can only strongly suggest that the obtained CNTs are really tubes but not fibers
High-stress study of bioinspired multifunctional PEDOT:PSS/nanoclay nanocomposites using AFM, SEM and numerical simulation
Beilstein J. Nanotechnol. 2017, 8, 2069–2082, doi:10.3762/bjnano.8.207
- structure in electrospun fibers for sensing a voltage response to loading while maintaining good flexibility within an application as smart clothing [25]. The integration of hard particles into a soft matrix has also gained interest for the design of advanced functional materials [25][26][27]. Recent
Enhancement of mechanical and electrical properties of continuous-fiber-reinforced epoxy composites with stacked graphene
Beilstein J. Nanotechnol. 2017, 8, 1909–1918, doi:10.3762/bjnano.8.191
- viscosity. This effect was less obvious with carbon or glass fibers, due to the lower surface energy of the carbon fibers or some incompatibility with the glass-fiber sizing. Proper choice of the surfactant and fine-tuning of the crosslink density at the interphase may provide further enhancements in thermo
- carbon epoxy composites have been studied, where the CNTs are either dispersed in the matrix and/or grafted on the carbon fibers [1][2]. However, the cost of CNTs limits intensive industrial applications. Other treatments have been attempted, among these, oxidation of the carbon fibers, plasma treatment
- of graphene, along with the high electrical conductivity, promote percolation thresholds much lower than with metallic powders, carbon fibers or carbon black [13]. Epoxy resins are used as a matrix in high-performance composite materials for aerospace structures, coatings and adhesives for a variety
Fabrication of carbon nanospheres by the pyrolysis of polyacrylonitrile–poly(methyl methacrylate) core–shell composite nanoparticles
Beilstein J. Nanotechnol. 2017, 8, 1897–1908, doi:10.3762/bjnano.8.190
- Dafu Wei Youwei Zhang Jinping Fu Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials
- carbonization treatments, polyacrylonitrile (PAN) can be converted into carbon. High-performance carbon fibers, carbon nanofiber membranes, 3D-ordered carbon materials, and carbon nanoparticles have been fabricated from various PAN precursors [28][29][30][31][32][33][34][35]. Discrete and well-defined carbon
Optical techniques for cervical neoplasia detection
Beilstein J. Nanotechnol. 2017, 8, 1844–1862, doi:10.3762/bjnano.8.186
- -vessels in the stroma of neoplastic tissue and stromal angiogenesis [28][29][30]. The observed drop in scattering in CIN 1–3 zones was attributed to the degradation of the stromal collagen matrix of the cervix related to both decomposition of collagen fibers and decrease in concentration of collagen cross
Oxidative stabilization of polyacrylonitrile nanofibers and carbon nanofibers containing graphene oxide (GO): a spectroscopic and electrochemical study
Beilstein J. Nanotechnol. 2017, 8, 1616–1628, doi:10.3762/bjnano.8.161
- manufacturing processes need to be improved to obtain high-performance composite structures [8]. Oxidative stabilization is a crucial heat-treatment process to produce carbon fibers from PAN fibers. PAN chains start to cross-link during this process and the newly composed polymeric structure can endure the
- rigors of high-temperature processing [9][10][11]. Oxidative stabilization is crucial to prevent melting or fusion of the fibers. Also, it minimizes volatilization of elemental carbon in the following carbonization step and maximizes the final carbon yield. Chemistry and mechanisms of complex oxidative
- (Princeton Applied Research, Tennessee, USA). The surface topography of the fibers was observed by atomic force microscopy (AFM) with Nanosurf Easy-Scan2TM software. AFM analyses were performed with a non-contact mode by using NCLR-10 model Al-coating silicon tips with 7 μm thickness, 225 μm length, 38 μm
Luminescent supramolecular hydrogels from a tripeptide and nitrogen-doped carbon nanodots
Beilstein J. Nanotechnol. 2017, 8, 1553–1562, doi:10.3762/bjnano.8.157
- with the presence of thinner bundles of fibers. Stress sweeps (Figure 2b,d,f) were employed to monitor variations in the hydrogel resistance to applied stress. Relative to the peptide alone (Figure 2b), NCND addition (Figure 2d,f) increased the linear viscoelastic region, thus improving the material
- (Figure 6). Once self-assembled, the tripeptide formed elongated fibrils that bundled into thicker fibers, forming a three-dimensional network that entrapped water. Typical hydrogel samples composed of peptide alone under TEM imaging appeared as networks of fibers of highly heterogeneous thickness, with a
- fibers observed by TEM upon addition of NCNDs. A minor discrepancy between the absolute values obtained with the two techniques could also be ascribed to sample holder geometries that differ in their surface-to-volume ratios (which is much higher in the CD cell), as well as different heat transfer
Fabrication of hierarchically porous TiO2 nanofibers by microemulsion electrospinning and their application as anode material for lithium-ion batteries
Beilstein J. Nanotechnol. 2017, 8, 1297–1306, doi:10.3762/bjnano.8.131
- electrospinning. However, coaxial electrospinning limits the further development of core–shell nanofibers because of its complicated spinneret, the limited number of suitable fluids and the unstable structure of the fibers. Recently the method of ME-ES has been developed to fabricate hierarchical nanofibers
- unmodified TiO2 nanofibers in Figure 4g reveals solid structures without pores in the cross-section. This sample was used as reference in the following investigation. As shown in Figure 4h, a representative TEM image of a single porous nanofiber confirms that the pores inside the fibers were oriented and
Surface-enhanced Raman spectroscopy of cell lysates mixed with silver nanoparticles for tumor classification
Beilstein J. Nanotechnol. 2017, 8, 1183–1190, doi:10.3762/bjnano.8.120
- CCD detector (iDus420, Andor, Ireland). The microscope was coupled to the Raman system with fibers of 65 µm core diameter. A 10×/0.25 objective lens (Leica, Germany) was used for all SERS measurements. The laser wavelength was calibrated using cyclohexane. The system was intensity calibrated using a
AgCl-doped CdSe quantum dots with near-IR photoluminescence
Beilstein J. Nanotechnol. 2017, 8, 1156–1166, doi:10.3762/bjnano.8.117
- devices. CdSe QDs deserve special attention because of their bright photoluminescence (PL), photostability, and a considerable number of methods for their synthesis. For many of the practical applications of QDs infrared PL (IR-PL) is very important: for the fabrication of optical fibers, lasers
Preparation of thick silica coatings on carbon fibers with fine-structured silica nanotubes induced by a self-assembly process
Beilstein J. Nanotechnol. 2017, 8, 1145–1155, doi:10.3762/bjnano.8.116
- carbon fibers with a silica shell is presented in this work. By immobilizing linear polyamines on the carbon fiber surface, the high catalytic activity of polyamines in the sol–gel-processing of silica precursors is used to deposit a silica coating directly on the fiber’s surface. The surface
- ; Introduction Carbon fibers are widely used as reinforcement in ceramic, metal matrix and carbon composites because of their outstanding properties, such as high specific strength, a high Young’s modulus, low expansion coefficient and relative flexibility [1]. For the application in adsorption processes, carbon
- field of adsorption enable the adaption to catalytic applications [2]. For example, cobalt diselenide nanoparticles can be grafted onto a carbon fiber felt creating a three-dimensional hydrogen evolution cathode based on the high conductivity of carbon fibers [3]. A primary objective of the present
Hierarchically structured nanoporous carbon tubes for high pressure carbon dioxide adsorption
Beilstein J. Nanotechnol. 2017, 8, 1135–1144, doi:10.3762/bjnano.8.115
- created by nanocasting [29]. All of these approaches have allowed for the synthesis of ordered hierarchical macro–mesoporous materials [24]. Electrospinning is a versatile technique for the synthesis of different one-dimensional forms such as fibers, tubes or wires for various applications such as gas
Investigation of growth dynamics of carbon nanotubes
Beilstein J. Nanotechnol. 2017, 8, 826–856, doi:10.3762/bjnano.8.85
- surface diffusion model for the growth of carbon fibers on metallic catalysts on the basis of the fact that the calculated activation energies of the growth were much lower than those of the bulk carbon diffusion in the metal. They suggested that the surface carbon diffusion on the catalytic particle was
Vapor deposition routes to conformal polymer thin films
Beilstein J. Nanotechnol. 2017, 8, 723–735, doi:10.3762/bjnano.8.76
- porous materials, including membranes, foams, and textiles, or irregular surface geometries, as well as for encapsulating fibers, nanowires, or particles [1]. For example, tailoring the surface energy of the pore walls of a separation membrane without obstructing the pore can enhance the passage of the
Fiber optic sensors based on hybrid phenyl-silica xerogel films to detect n-hexane: determination of the isosteric enthalpy of adsorption
Beilstein J. Nanotechnol. 2017, 8, 475–484, doi:10.3762/bjnano.8.51
- , respectively. The films were synthesized by the sol–gel method and affixed to the end of optical fibers by the dip-coating technique. Fourier transform infrared spectroscopy, N2 adsorption–desorption at 77 K and X-ray diffraction analysis were used to characterize the xerogels. At a given pressure of n-hexane
- , it loses translational entropy. The aim of this study was to assess the effect of temperature on the sensitivity of hybrid phenyl-silica films to n-hexane and to determine the variation of the isosteric enthalpy of adsorption. Materials and Methods Optical fibers and preparation of xerogel films
- Multimode optical fibers with a graded refractive index were chosen with core and cladding diameters of 62.5 and 125 µm, respectively (Telnet, Zaragoza, Spain). The effective refractive index was 1.497 at 850 nm. The fibers were first cut and peeled with a stripper (Millar, Cronwell, CT, USA), and the core
Studying friction while playing the violin: exploring the stick–slip phenomenon
Beilstein J. Nanotechnol. 2017, 8, 159–166, doi:10.3762/bjnano.8.16
- sounds. A violin, for example, can produce musical notes whose frequency and intensity (brilliance) can be varied as required during the performance by rubbing a bundle of fibers against metal strings [8]. The contact surface is then reduced to the touching points of perpendicular cylinders, where
- like the one corresponding to sample 2 may prevent this movement in the dynamic friction range. This is indeed similar to that observed in the sound waves recorded from clean fibers in Figure 3: a peak is achieved, but quickly diminishes to a flat region. Instead, sample 1 shows a more regular saw
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