Electrospun one-dimensional nanostructures: a new horizon for gas sensing materials

• Muhammad Imran,
• Nunzio Motta and
• Mahnaz Shafiei

Beilstein J. Nanotechnol. 2018, 9, 2128–2170, doi:10.3762/bjnano.9.202

• materials used as an active sensing layer, including polymers, metal oxide semiconductors, graphene, and their composites or their functionalized forms. The material properties of these electrospun fibers and their sensing performance toward different analytes are explained in detail and correlated to the

• these techniques, electrospinning is one of the most versatile and robust techniques for synthesis of functional nanofibers with unique structure and diverse properties [37][38][39][40]. The diameter of these functional fibers range between sub-micrometre to nanometre. The versatility of electrospinning

• electrospinning as well as electrospraying. Electrospinning is a simple, robust and low-cost technique to generate polymer and composite fibers ranging from nanometres to a few micrometres in diameter [46][47]. In electrospinning, a high voltage source is used to produce fine fibers from a polymer solution or

Metal-free catalysis based on nitrogen-doped carbon nanomaterials: a photoelectron spectroscopy point of view

• Mattia Scardamaglia and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2018, 9, 2015–2031, doi:10.3762/bjnano.9.191

• discovery of their catalytic performance in the ORR: beginning with nitrogen-doped carbon fibres (2006 [18]), followed by carbon nanotubes (2009 [19]) and finally graphene (2010 [20]). In 2006, Matter and Ozkan reported on a metal-free ORR catalyst containing nitrogen-doped carbon fibers. The authors

• compared the ORR activity of the fibers grown with and without iron. The latter showed significant ORR activity, although they were less performant than the iron-containing catalyst [18]. The first metal-free catalyst that showed an ORR activity superior to commercial Pt in alkaline fuel cells was reported

Biomimetic and biodegradable cellulose acetate scaffolds loaded with dexamethasone for bone implants

• Aikaterini-Rafailia Tsiapla,
• Varvara Karagkiozaki,
• Veroniki Bakola,
• Foteini Pappa,
• Panagiota Gkertsiou,
• Eleni Pavlidou and
• Stergios Logothetidis

Beilstein J. Nanotechnol. 2018, 9, 1986–1994, doi:10.3762/bjnano.9.189

• are placed as coatings in medical devices in order to enhance the biocompatibility [2][3][4]. One technique to produce such coatings is electrospinning, which yields long micro- and nanofibers [5]. More specifically, physical and synthetic polymeric fibers of 30–20000 nm in length are produced by

• and to be subsequently used for SEM analysis. Results and Discussion Development of drug-free and dexamethasone-loaded CA scaffolds Fibers of drug-free CA and CA loaded with dexamethasone were created through electrospinning. SEM and AFM indicated the successful fabrication of those structures (Figure

•  1). Continuous fibers with smooth surface and free of any beads and other defects were obtained. In vitro degradation of non-woven CA fibers was investigated in DMEM solution at 37 °C over a period of 5 months (Figure 2). It should be mentioned that, CA is a semi-synthetic polymer, produced by the

Preparation of micro/nanopatterned gelatins crosslinked with genipin for biocompatible dental implants

• Reika Makita,
• Tsukasa Akasaka,
• Seiichi Tamagawa,
• Yasuhiro Yoshida,
• Saori Miyata,
• Hirofumi Miyaji and
• Tsutomu Sugaya

Beilstein J. Nanotechnol. 2018, 9, 1735–1754, doi:10.3762/bjnano.9.165

• natural tooth and periodontium, or their biomimetic equivalents. Collagen is a basic component of the periodontium and plays an important role in the function of the periodontal unit [15]. Bundles of collagen fibers in the periodontal ligament, including Sharpey’s fibers, are vertically arranged from the

• surface of the tooth to the alveolar bone by their position and orientation. The resulting periodontal ligament fibers exhibit micro/nanopatterns arising as a result of the shape of bundles of collagen fibers [16][17][18]. Thus, coating surfaces with collagen has been used for dental implants to allow

• implants [21][22]. It is also used as an absorbable hemostatic sponge to provide an occlusive matrix [23][24] and as a bone healing material in tissue engineering [25][26] in the field of dentistry. Recent studies have attempted to regenerate collagen fibers, lost as a result of periodontal disease, using

Surface characterization of nanoparticles using near-field light scattering

• Eunsoo Yoo,
• Yizhong Liu,
• Chukwuazam A. Nwasike,
• Sebastian R. Freeman,
• Brian C. DiPaolo,
• Bernardo Cordovez and
• Amber L. Doiron

Beilstein J. Nanotechnol. 2018, 9, 1228–1238, doi:10.3762/bjnano.9.114

• output edge where transmitted light is collected by a photodetector. Three polarization-maintaining optical fibers are supported by a silicon v-groove array and are optically aligned to the three waveguides permanently bonded to the chips. Each chip has two through-holes for fluidic access. Fluid lines

• deionized water. Optofluidic chip is secured in a chip cassette and is permanently bonded to three optical fibers, which deliver laser light to the three waveguides on the chip surface. The chip also has a microfluidic channel with inlet and outlet holes. (A) Near-field light scattering with relevant forces

Review on nanoparticles and nanostructured materials: history, sources, toxicity and regulations

• Jaison Jeevanandam,
• Ahmed Barhoum,
• Yen S. Chan,
• Alain Dufresne and
• Michael K. Danquah

Beilstein J. Nanotechnol. 2018, 9, 1050–1074, doi:10.3762/bjnano.9.98

• town, the main source of atmospheric micro- and nanoparticles is automobile exhaust [88]. Amongst the types of automobile exhaust, diesel engines release 20–130 nm sized particles whereas gasoline engines release 20–60 nm sized particles [89][90]. It has been found that CNTs and fibers are released as

• than 10 μm are released into the atmosphere when larger buildings are demolished [103]. Other than building debris, lead, glass, respirable asbestos fibers and other toxic particles from household materials are released as nanosized particles around the site of building demolition [103]. Cigarette

• drugs that can inhibit the growth of these harmful bacteria in its early stage. Nanoparticles and nanostructures in plants Wood is made of natural fibers that are considered as cellular hierarchical bio-composites. Natural fibers are composites of cellulosic-fibrils at the nanoscale level. The simplest

Bioinspired self-healing materials: lessons from nature

• Joseph C. Cremaldi and
• Bharat Bhushan

Beilstein J. Nanotechnol. 2018, 9, 907–935, doi:10.3762/bjnano.9.85

• cell size/shape [14]. Figure 2A shows the hierarchical levels of muscle structure in a human, building from the basic components of actin and myosin proteins to sarcomeres and muscle fibers that form a muscle [39]. Skeletal muscle is striated and used for voluntary movements. Smooth, or nonstriated

• , muscle is used for involuntary muscle movements such as breathing and digestion. Last, cardiac muscles are involuntary, striated muscles used in the movement of the heart and are organized into a complex linkage between sarcomere fibers. Invertebrates have several types of muscles related to body

Single-step process to improve the mechanical properties of carbon nanotube yarn

• Maria Cecilia Evora,
• Xinyi Lu,
• Nitilaksha Hiremath,
• Nam-Goo Kang,
• Kunlun Hong,
• Roberto Uribe,
• Gajanan Bhat and
• Jimmy Mays

Beilstein J. Nanotechnol. 2018, 9, 545–554, doi:10.3762/bjnano.9.52

• Science and Engineering, University of Tennessee, Knoxville, TN 37996, USA Center for Nanophase Materials Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA College of Applied Engineering, Sustainability and Technology, Kent State University, Kent, OH 44240, USA Fibers and textiles

• Department, University of Georgia, Athens, GA 30602, USA 10.3762/bjnano.9.52 Abstract Carbon nanotube (CNT) yarns exhibit low tensile strength compared to conventional high-performance carbon fibers due to the facile sliding of CNTs past one another. Electron beam (e-beam) irradiation was employed for in a

• challenge to assemble CNTs in materials on the macroscopic scale [3]. Because of the difficulties in dispersing pristine CNTs in polymers, the assembly of CNTs into macroscopic fibers, with the tubes aligned parallel along the CNT yarn axis, has been focused on [4][5][6][7][8][9][10][11][12][13]. There are

Ultralight super-hydrophobic carbon aerogels based on cellulose nanofibers/poly(vinyl alcohol)/graphene oxide (CNFs/PVA/GO) for highly effective oil–water separation

• Zhaoyang Xu,
• Huan Zhou,
• Sicong Tan,
• Xiangdong Jiang,
• Weibing Wu,
• Jiangtao Shi and
• Peng Chen

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

• Razieh Beigmoradi,
• Abdolreza Samimi and
• Davod Mohebbi-Kalhori

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

• Ruiyuan Zhuang,
• Shanshan Yao,
• Maoxiang Jing,
• Xiangqian Shen,
• Jun Xiang,
• Tianbao Li,
• Kesong Xiao and
• Shibiao Qin

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

• Baeckkyoung Sung and
• Min-Ho Kim

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

• Stefanie Krüger,
• Michael Schwarze,
• Otto Baumann,
• Christina Günter,
• Michael Bruns,
• Christian Kübel,
• Dorothée Vinga Szabó,
• Rafael Meinusch,
• Verónica de Zea Bermudez and
• Andreas Taubert

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

• Doina Manaila Maximean,
• Octavian Danila,
• Pedro L. Almeida and
• Constantin Paul Ganea

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

• Agata Siarkowska,
• Miłosz Chychłowski,
• Daniel Budaszewski,
• Bartłomiej Jankiewicz,
• Bartosz Bartosewicz and
• Tomasz R. Woliński

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

• Christian Lutz,
• Julia Syurik,
• C. N. Shyam Kumar,
• Christian Kübel,
• Michael Bruns and
• Hendrik Hölscher

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

• Egor V. Lobiak,
• Lyubov G. Bulusheva,
• Ekaterina O. Fedorovskaya,
• Yury V. Shubin,
• Pavel E. Plyusnin,
• Pierre Lonchambon,
• Boris V. Senkovskiy,
• Zinfer R. Ismagilov,
• Emmanuel Flahaut and
• Alexander V. Okotrub

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

• Fan Tu,
• Martin Drost,
• Imre Szenti,
• Janos Kiss,
• Zoltan Kónya and
• Hubertus Marbach

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

• Alfredo J. Diaz,
• Hanaul Noh,
• Tobias Meier and
• Santiago D. Solares

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

• Naum Naveh,
• Olga Shepelev and
• Samuel Kenig

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

• Dafu Wei,
• Youwei Zhang and
• Jinping Fu

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

• Tatiana Novikova

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

• İlknur Gergin,
• Ezgi Ismar and
• A. Sezai Sarac

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

• Maria C. Cringoli,
• Slavko Kralj,
• Marina Kurbasic,
• Massimo Urban and
• Silvia Marchesan

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

• Jin Zhang,
• Yibing Cai,
• Xuebin Hou,
• Xiaofei Song,
• Pengfei Lv,
• Huimin Zhou and
• Qufu Wei

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