Bio-imaging with the helium-ion microscope: A review

• Matthias Schmidt,
• James M. Byrne and
• Ilari J. Maasilta

Beilstein J. Nanotechnol. 2021, 12, 1–23, doi:10.3762/bjnano.12.1

Piezoelectric sensor based on graphene-doped PVDF nanofibers for sign language translation

• Shuai Yang,
• Xiaojing Cui,
• Rui Guo,
• Zhiyi Zhang,
• Shengbo Sang and
• Hulin Zhang

Beilstein J. Nanotechnol. 2020, 11, 1655–1662, doi:10.3762/bjnano.11.148

• concentrated in the bent part of the material, and the potential is generated on the opposite side of the device. Electrospinning is used to manufacture GR-doped PVDF fibers. The overall process is shown in Figure 2a. Firstly, GR is dispersed in dimethylformamide (DMF). After ultrasonic treatment, PVDF powder

• is added under stirring to yield the spinning solution for electrospinning. After preparation of the fibers, an aqueous solution of Ti3C2 MXene and Ag NWs is sprayed on both sides of the material and then dried. Finally, the nanowire membrane is covered on both sides with PDMS to obtain the

• fibers is shown in Figure 2e. As the concentration increases, the tensile strength of the material increases. The output of the self-powered PES was measured with a series of experiments. Figure 3a,b shows that when the pressure gradually increases, the generated piezoelectric voltage increases. The

Structure and electrochemical performance of electrospun-ordered porous carbon/graphene composite nanofibers

• Yi Wang,
• Yanhua Song,
• Chengwei Ye and
• Lan Xu

Beilstein J. Nanotechnol. 2020, 11, 1280–1290, doi:10.3762/bjnano.11.112

• configurations were used as a material to fabricate supercapacitor electrodes. These nanofibers were synthesized by applying a modified parallel electrode to the electrospinning method (MPEM) in order to generate electrospun polyacrylonitrile (PAN) nanofibers containing graphene. After synthesis, these fibers

• pores were formed not only at the surface of the CCGNFs but also inside these fibers. The pore formation not only increased the specific surface area of the CGCNFs but also had a significant influence on the ionic conduction in the electrolyte solution, thereby affecting the final electrochemical

• increase in the pore volume of the OPCGCNFs was mainly due to the increase in the number of channels in the fibers, leading to an increase in the ion transport rate. This shows that proper microporous/mesoporous structures can facilitate the transport and adsorption of ions in the electrode, which favors

Photothermally active nanoparticles as a promising tool for eliminating bacteria and biofilms

• Mykola Borzenkov,
• Piersandro Pallavicini,
• Angelo Taglietti,
• Laura D’Alfonso,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2020, 11, 1134–1146, doi:10.3762/bjnano.11.98

• that there was wound healing of the infected site, while untreated areas resulted in necrotic muscular fibers and bacterial infiltration. Applications of other types of nanoparticles for photothermally induced bacteria and biofilm ablation Besides the widely studied gold nanoparticles, other inorganic

Straightforward synthesis of gold nanoparticles by adding water to an engineered small dendrimer

• Sébastien Gottis,
• Régis Laurent,
• Vincent Collière and
• Anne-Marie Caminade

Beilstein J. Nanotechnol. 2020, 11, 1110–1118, doi:10.3762/bjnano.11.95

• fibers stabilized by amines (AuI, ca. 3.25 Å) [10], but slightly longer than in the case of gold particles in silica glass and gold foil (2.84 Å) [61] or in bulk gold (2.88427 Å) [10]. The dependence between the gold nanoparticle shape and the conditions in which they were generated is the subject of a

Microwave-induced electric discharges on metal particles for the synthesis of inorganic nanomaterials under solvent-free conditions

• Vijay Tripathi,
• Harit Kumar,
• Anubhav Agarwal and
• Leela S. Panchakarla

Beilstein J. Nanotechnol. 2020, 11, 1019–1025, doi:10.3762/bjnano.11.86

• fibers [20][21]. Thus, sulfur was introduced to the reaction mixtures to improve the yield of nanorods. The microwave treatment of activated Zn metal with g-C3N4 and sulfur in a Teflon container produced ZnF2 nanorods in high yield. The XRD patterns in Figure S5 in Supporting Information File 1 confirm

Wet-spinning of magneto-responsive helical chitosan microfibers

• Dorothea Brüggemann,
• Johanna Michel,
• Naiana Suter,
• Matheus Grande de Aguiar and
• Michael Maas

Beilstein J. Nanotechnol. 2020, 11, 991–999, doi:10.3762/bjnano.11.83

• to the macroscale. Due to their ability to store mechanical energy and to optimize the accessible surface area, helical shapes contribute particularly to motion-driven processes and structural reinforcement. Due to these special features, helical fibers have become highly attractive for

• biotechnological and tissue engineering applications. However, there are only a few methods available for the production of biocompatible helical microfibers. Given that, we present here a simple technique for the fabrication of helical chitosan microfibers with embedded magnetic nanoparticles. Composite fibers

• were prepared by wet-spinning and coagulation in an ethanol bath. Thereby, no toxic components were introduced into the wet-spun chitosan fibers. After drying, the helical fibers had a diameter of approximately 130 µm. Scanning electron microscopy analysis of wet-spun helices revealed that the magnetic

Atomic layer deposition for efficient oxygen evolution reaction at Pt/Ir catalyst layers

• Stefanie Schlicht,
• Korcan Percin,
• Stefanie Kriescher,
• André Hofer,
• Claudia Weidlich,
• Matthias Wessling and
• Julien Bachmann

Beilstein J. Nanotechnol. 2020, 11, 952–959, doi:10.3762/bjnano.11.79

• consider here two distinct catalyst preparation methods. As a standard method used in the engineering context, we perform an acid etch of the titanium fibers (to generate surface roughness and thereby increase the specific surface area), followed by dip-coating of a noble metal salt precursor solution on

• the Ti support and subsequent thermal decomposition to the corresponding elements [16][17][18]. As an academic method yielding better control of the electrode surface geometry, we perform an “anodization” of the Ti fibers to generate an ordered porous layer, followed by atomic layer deposition (ALD

• . Finally, the samples were calcinated at 450 °C to generate the metallic catalyst. Figure 1 presents the SEM and EDX characterization of the titanium felts obtained by this method. Figure 1a presents the untreated felt, the titanium fibers of which are clearly visible. Figure 1b shows the felt after acid

A 3D-polyphenylalanine network inside porous alumina: Synthesis and characterization of an inorganic–organic composite membrane

• Jonathan Stott and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2020, 11, 938–951, doi:10.3762/bjnano.11.78

• Fores et al. The authors realized peptide hydrogels in a porous melamine foam for use in continuous flow chemistry [30]. Other polyelectrolytes such as poly(acrylic acid) were prepared using an ozone-induced grafting process for cellulose fibers [31]. Hydrophobic foams of poly(γ-benzyl-ʟ-glutamate-co-ʟ

Integrated photonics multi-waveguide devices for optical trapping and Raman spectroscopy: design, fabrication and performance demonstration

• Gyllion B. Loozen,
• Arnica Karuna,
• Mohammad M. R. Fanood,
• Erik Schreuder and
• Jacob Caro

Beilstein J. Nanotechnol. 2020, 11, 829–842, doi:10.3762/bjnano.11.68

• suspension away from surfaces [2]. For on-chip trapping and Raman spectroscopy, the dual-beam trap based on fibers or integrated photonics waveguides has been studied extensively [3][4][5][6]. This trap comprises two excitation fibers or excitation waveguides, which emit counter-propagating beams into a

• spectra are induced and collected by an external spectroscopy system. This work was extended in [4] by using fibers for both trapping of single polystyrene beads and for inducing and collecting Raman signals for the trapped beads. In our previous work [5], we used integrated photonics Si3N4 waveguides of

• the facets and disturbance of its Raman spectrum due to particle–surface interaction, which are effects to be avoided. It is of interest to compare the devices described in [3][4][5][6] with the long hollow core fibers for fiber-enhanced Raman spectroscopy used in [7]. With the technique applied in [7

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

• Stefania Castelletto,
• Faraz A. Inam,
• Shin-ichiro Sato and
• Alberto Boretti

Beilstein J. Nanotechnol. 2020, 11, 740–769, doi:10.3762/bjnano.11.61

Preparation, characterization and photocatalytic performance of heterostructured CuO–ZnO-loaded composite nanofiber membranes

• Wei Fang,
• Liang Yu and
• Lan Xu

Beilstein J. Nanotechnol. 2020, 11, 631–650, doi:10.3762/bjnano.11.50

• investigated using scanning electron microscopy (SEM, Hitachi S-4800, Japan). The matrix morphology and fiber diameter distribution were determined using the Image J software (National Institute of Mental Health, Bethesda, Maryland, USA). The diameter of 100 randomly selected fibers in each sample were chosen

• evenly distributed on the surface of the nanofibers, which provide a seed layer for further hydrothermal growth. When the weight ratio reaches 1:1, the nanofibers the particles aggregated and the fibers become bundled. Therefore, a weight ratio of 1:2 was chosen as the optimum parameter for further

Synthesis of amorphous and graphitized porous nitrogen-doped carbon spheres as oxygen reduction reaction catalysts

• Maximilian Wassner,
• Markus Eckardt,
• Andreas Reyer,
• Thomas Diemant,
• Michael S. Elsaesser,
• R. Jürgen Behm and
• Nicola Hüsing

Beilstein J. Nanotechnol. 2020, 11, 1–15, doi:10.3762/bjnano.11.1

• fibers [7][8][9][10], N-doped 3D ordered (meso)porous carbon materials [11], N-doped carbon composites (e.g., carbon nanotubes/graphene) [12], and N-doped carbon spheres [13][14] to graphitic-C3N4 carbon nitride composites [15]. In the present work we report results of a systematic study on the synthesis

• (HRTEM) images of the resulting particles showed that the graphite layers are arranged along the longitudinal axis of the fibers [37]. After the acidic washing process, neither XPS nor EDX showed, for g-NCS-850 and g-NCS-1000, Fe or Fe3C particles within the spheres, which are commonly found for the Fe

• graphite layers Lc of 7.6 and 8.6 nm, respectively, which matches very well to the thickness of the carbon fibers as detected in the TEM images. The degree of graphitization, g, is calculated using the interplanar distance d002: g = (0.344 nm – d002)/(0.344 nm – 0.3354 nm), with 0.344 nm for the

Fully amino acid-based hydrogel as potential scaffold for cell culturing and drug delivery

• Dávid Juriga,
• Evelin Sipos,
• Orsolya Hegedűs,
• Gábor Varga,
• Miklós Zrínyi,
• Krisztina S. Nagy and
• Angéla Jedlovszky-Hajdú

Beilstein J. Nanotechnol. 2019, 10, 2579–2593, doi:10.3762/bjnano.10.249

• Institutional Committee of Science and Research Ethics. The number of the ethical permission is: 17458/2012/EKU. After extraction, the teeth were immediately placed into a sterile cell culture medium. The viable periodontal fibers were removed from the tooth surface, put into a sterile box with a sterile blade

• and digested in 1 mL collagenase I solution (1 mg/mL, Sigma-Aldrich, St. Louis, Missouri) for 1 h at 37 °C. The samples were vortexed every 10 min. After digestion, the fibers were mechanically loosened with needles (21G and 18G) and were centrifuged for 5 min at 250g. The PDLCs were maintained in a

Advanced hybrid nanomaterials

• Andreas Taubert,
• Fabrice Leroux,
• Pierre Rabu and
• Verónica de Zea Bermudez

Beilstein J. Nanotechnol. 2019, 10, 2563–2567, doi:10.3762/bjnano.10.247

• ) was employed in “Topochemical engineering of composite hybrid fibers using layered double hydroxides and abietic acid” [27]. In this work, a composite hybrid was formed using cellulose fibers with LDH particles growing on their surface and then covered by abietic acid. The fibers were tested against

Four self-made free surface electrospinning devices for high-throughput preparation of high-quality nanofibers

• Yue Fang and
• Lan Xu

Beilstein J. Nanotechnol. 2019, 10, 2261–2274, doi:10.3762/bjnano.10.218

• high-throughput tipless electrospinning via a circular cylindrical electrode. Shin et al. [19] used a multiple vertical rod setup for needleless ES to fabricate submicrometer polymer fibers. Moon et al. developed a syringeless electrospinning technique with a helically probed rotating cylinder for

• fibers were characterized using the Image J software (National Institute of Mental Health, Bethesda, MD, USA) to study 100 randomly chosen nanofibers in 50 SEM images. The mass of the PAN nanofibers was measured as follows using a precise electronic balance (XJ120A, Precisa, Shanghai, China): where W is

A novel all-fiber-based LiFePO₄/Li₄Ti₅O₁₂ battery with self-standing nanofiber membrane electrodes

• Li-li Chen,
• Hua Yang,
• Mao-xiang Jing,
• Chong Han,
• Fei Chen,
• Xin-yu Hu,
• Wei-yong Yuan,
• Shan-shan Yao and
• Xiang-qian Shen

Beilstein J. Nanotechnol. 2019, 10, 2229–2237, doi:10.3762/bjnano.10.215

• used as self-standing electrodes for lithium-ion batteries. The structure and morphology of the fibers, and the electrochemical performance of the electrodes and the full battery were characterized. The results show that the LiFePO4 and Li4Ti5O12 fiber membrane electrodes exhibit good rate and cycle

• grains in the fibers. SEM images of LiFePO4 and Li5Ti4O12 nanofiber membranes are shown in Figure 3. It can be seen that the fiber membranes after heat treatment exhibit a 3D network structure, which is the reason for the high flexibility of the electrode. The high-magnification SEM images show uniform

• growth of crystal grains on the surface of the fibers for both LiFePO4 and Li5Ti4O12. The fiber diameter is less than 1 μm, and the grain size is between 200 and 300 nm. There are numerous channels between the fibers. This structure is beneficial for the penetration of electrolyte and the contact between

Review of advanced sensor devices employing nanoarchitectonics concepts

• Katsuhiko Ariga,
• Tatsuyuki Makita,
• Masato Ito,
• Taizo Mori,
• Shun Watanabe and
• Jun Takeya

Beilstein J. Nanotechnol. 2019, 10, 2014–2030, doi:10.3762/bjnano.10.198

• particles [122]. Mesoporous carbons were used for sensing of tannins in acidic aqueous environment with highly cooperative adsorption in the mesochannels [123]. The nanoarchitectonic construction of carbon nanocages with high surface mesoporous structures [124] was integrated with electrospun polymer fibers

Optimization and performance of nitrogen-doped carbon dots as a color conversion layer for white-LED applications

• Tugrul Guner,
• Hurriyet Yuce,
• Didem Tascioglu,
• Eren Simsek,
• Umut Savaci,
• Aziz Genc,
• Servet Turan and
• Mustafa M. Demir

Beilstein J. Nanotechnol. 2019, 10, 2004–2013, doi:10.3762/bjnano.10.197

• as color conversion layers in a white-LED configuration to generate white light. In order to resolve the red deficiency of this configuration, a commercial red phosphor was integrated into the system. Moreover, the N-CDots were also processed into polymer/N-CDot composite fibers, for which we

• determined the amount of N-CDots that yielded adequate white-light properties. Finally, we showed that white light with excellent properties could be generated by employing both of the fabricated N-CDot composites either as drop-cast films or composite fibers. Hence, N-CDots provide a promising alternative

• into thin films and fibers. Throughout this study, the term “water-based” is used to emphasize that during the fabrication of the color conversion layers, the CDots and the PVP were taken from their dispersion or solution in (mainly) distilled water without introducing any toxic or organic solvents

Facile synthesis of carbon nanotube-supported NiO//Fe₂O₃ for all-solid-state supercapacitors

• Shengming Zhang,
• Xuhui Wang,
• Yan Li,
• Xuemei Mu,
• Yaxiong Zhang,
• Jingwei Du,
• Guo Liu,
• Xiaohui Hua,
• Yingzhuo Sheng,
• Erqing Xie and
• Zhenxing Zhang

Beilstein J. Nanotechnol. 2019, 10, 1923–1932, doi:10.3762/bjnano.10.188

• the as-obtained CC-CNT@Fe2O3 is shown in Figure 2b, where Fe2O3 coats all carbon fibers well. The space between CNTs provides enormous room for Fe2O3 growth, and the obtained CNT@Fe2O3 are entangled with each other and sticky to the CC (Figure 2c). N2 adsorption–desorption isotherm and Barrett–Joyner

High-tolerance crystalline hydrogels formed from self-assembling cyclic dipeptide

• Yongcai You,
• Ruirui Xing,
• Qianli Zou,
• Feng Shi and
• Xuehai Yan

Beilstein J. Nanotechnol. 2019, 10, 1894–1901, doi:10.3762/bjnano.10.184

• environments. Results and Discussion Preparation and characterization of the hydrogel C-WY was chosen as a model peptide to investigate the self-assembly of CDPs. A nontransparent hydrogel with a dense network of fibers was obtained simply by mixing a solution of C-WY in DMSO (2 mg, 20 μL) with water (480 μL

• 3317 cm−1, indicating the formation of strong hydrogen bonds between C-WY molecules in the hydrogel (Figure 1B). Further characterization by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) was performed to inspect the morphology of the hydrogel (Figure 1C,D). The fibers in

• the hydrogel are 100 ± 50 nm in width and dozens of micrometers in length. In addition, dense three-dimensional fibrous networks cross-linked by slender fibers were clearly observed. The cross-linked networks are beneficial to improving the stability of the hydrogels at extreme conditions [48]. The

Prestress-loading effect on the current–voltage characteristics of a piezoelectric p–n junction together with the corresponding mechanical tuning laws

• Wanli Yang,
• Shuaiqi Fan,
• Yuxing Liang and
• Yuantai Hu

Beilstein J. Nanotechnol. 2019, 10, 1833–1843, doi:10.3762/bjnano.10.178

• been investigated by Dai et al. [24] and Yang and co-workers [25]. The mechanical behavior of composite fibers with piezoelectric dielectrics and non-piezoelectric semiconductors have also been studied by Cheng et al. [26] and Luo and co-workers [27]. For piezoelectric p–n junctions, it becomes

Biocatalytic oligomerization-induced self-assembly of crystalline cellulose oligomers into nanoribbon networks assisted by organic solvents

• Yuuki Hata,
• Yuka Fukaya,
• Toshiki Sawada,
• Masahito Nishiura and
• Takeshi Serizawa

Beilstein J. Nanotechnol. 2019, 10, 1778–1788, doi:10.3762/bjnano.10.173

• chains [42]. In other words, a higher uniformity of the chain lengths leads to higher integrity of the crystals. Scanning electron microscopy (SEM) was used to uncover the nanomorphology of the gels. The images revealed a well-grown network structure composed of nanoribbon-shaped fibers (Figure 9), which

Novel hollow titanium dioxide nanospheres with antimicrobial activity against resistant bacteria

• Carol López de Dicastillo,
• Cristian Patiño,
• María José Galotto,
• Yesseny Vásquez-Martínez,
• Claudia Torrent,
• Daniela Alburquenque,
• Alejandro Pereira and
• Juan Escrig

Beilstein J. Nanotechnol. 2019, 10, 1716–1725, doi:10.3762/bjnano.10.167

• nanostructures, such as fibers and spherical particles, through the application of a high voltage that breaks the surface tension of the droplet of a polymeric solution located at the tip of a needle [16][17]. The morphology of the resulting nanostructures is influenced by the properties of the polymeric

• ) PVP polymeric solution. Unlike the common electrospinning process, which results in fibers by the continuous stretching of the Taylor cone through the application of a voltage to a polymeric solution with high viscosity, this case was considered an “electrospraying” process, which resulted in

Tuning the performance of vanadium redox flow batteries by modifying the structural defects of the carbon felt electrode

• Ditty Dixon,
• Deepu Joseph Babu,
• Aiswarya Bhaskar,
• Hans-Michael Bruns,
• Joerg J. Schneider,
• Frieder Scheiba and
• Helmut Ehrenberg

Beilstein J. Nanotechnol. 2019, 10, 1698–1706, doi:10.3762/bjnano.10.165

• process of the PAN fibers or simply the atmospheric ageing of the felt. It is already known from the literature that graphitization or atmospheric ageing can leave some aliphatic or polyaromatic tar-like residues on the surface of the felt [6][23]. Thus, it can be concluded that apart from inducing N

• -doping, the N2 plasma treatment also increased the apparent graphite amount on the surface by removing the aliphatic groups (C–H and C–C) from the surface of the fibers. The schematic representation of N-doping induced by the N2 plasma treatment in a graphite lattice is shown in Figure 3. From the

• scanning electron microscopy (SEM) analysis, it can be seen that the surface morphology of the fibers of both samples looked identical and thus any kind of surface roughening leading to an increase of the surface area can be ignored. This is further supported by our previous study were the BET measurements