Simulation of gas sensing with a triboelectric nanogenerator

• Kaiqin Zhao,
• Hua Gan,
• Huan Li,
• Ziyu Liu and
• Zhiyuan Zhu

Beilstein J. Nanotechnol. 2021, 12, 507–516, doi:10.3762/bjnano.12.41

• simulation, we measured the potential difference between the outer surfaces of the two dielectric materials as ds is gradually increased from 0.1 to 1 mm, as shown in Figure 3c, which also reflects the influence of the distance between the two triboelectric materials on the potential. In practice, it is

• driven by the potential difference between the two sides. Figure 5e,f shows the electric potential in the simulation of rectangle, isosceles triangle, and right-angled triangle. The electric potentials obtained for the three models are basically the same, but it can be found that the electric potential

• materials approach or move away from each other, other substances, such as water vapor, carbon dioxide, and other gases, can pass through the gap. We present a simulation with water vapor under ideal conditions, that is, the surface charge density may be changed during the experiment. A simplified two

Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles

• Paulina Filipczak,
• Krzysztof Hałagan,
• Jacek Ulański and
• Marcin Kozanecki

Beilstein J. Nanotechnol. 2021, 12, 497–506, doi:10.3762/bjnano.12.40

• average size of 34 ± 14 nm. The temperature experiment results showed a higher enhancement with temperature increase. Performed simulation studies revealed a slowdown of the mobility of the water molecules close to the surface of AgNPs. Keywords: Dynamic lattice liquid (DLL) simulations; liquid water

• metal surfaces, which is very different in comparison to bulk water [24]. It was explained that the ordering of water molecules near to AgNPs is due to the electrostatic interactions between water and AgNPs. Some simulation studies also reported the enhancement of hydrogen bonds in the water structure

• AgNPs. Therefore, one can simply conclude that more energy is needed to destroy the water structure in the AgNPs dispersion than in pure water. Simulation studies Dynamic lattice liquid (DLL) simulation studies based on the face-centred cubic (FCC) lattice approach were performed, in which averaged

Reconstruction of a 2D layer of KBr on Ir(111) and electromechanical alteration by graphene

• Zhao Liu,
• Antoine Hinaut,
• Stefan Peeters,
• Sebastian Scherb,
• Ernst Meyer,
• Maria Clelia Righi and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2021, 12, 432–439, doi:10.3762/bjnano.12.35

• energies of the K+ (Br−) ions on Ir, an energy difference equivalent to the one shown in Equation 1 was performed, where the total energy of the isolated K (Br) atoms was considered instead of EKBr. To calculate the partial charges on the atoms in the simulation cells, the Bader method was chosen [43][44

• a triple-atom duplication along “BBC”) indicated in (a), respectively. DFT simulation of a monolayer KBr on Ir(111). (a) Optimization of a reconstructed KBr layer on Ir(111) with a cell size of 4 × 2 superimposed on the Ir(111) model and experimental data (Br− in red and K+ in blue, the size of the

Scanning transmission helium ion microscopy on carbon nanomembranes

• Daniel Emmrich,
• Annalena Wolff,
• Nikolaus Meyerbröker,
• Jörg K. N. Lindner,
• André Beyer and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2021, 12, 222–231, doi:10.3762/bjnano.12.18

• simulation was run with 50,000 ions at energies of either 15 or 30 keV. The CNM was approximated as a carbon layer with a thickness between 0.3 and 13 nm. From the SRIM output file of all transmitted ions, an angular distribution was generated (see Figure 3a). The simulation results, obtained for different

• between 3 nm thin and 1.5 nm thin CNMs for different acceptance angles. While the difference in the signal is low at small and large angles, the simulation results show that it reaches a maximum at an acceptance angle of 10 mrad. Depending on the acceptance angle of the detector, maximum brightness or

• maximum contrast between different thicknesses are adjustable. The simulation results suggest that smaller acceptance angles are ideal for applications where brightness is important, such as end-point detection for, for example, nanopores. Especially on extremely thin membranes such as CNMs, milling

Determination of elastic moduli of elastic–plastic microspherical materials using nanoindentation simulation without mechanical polishing

• Hongzhou Li and
• Jialian Chen

Beilstein J. Nanotechnol. 2021, 12, 213–221, doi:10.3762/bjnano.12.17

• depends on the indentation depth. It demonstrates that nanoindentation on microspherical materials exhibits a “size effect”. Keywords: elastic–plastic; microsphere; nanoindentation; Oliver–Pharr method; simulation; Introduction Instrumented nanoindentation is the most commonly used technique for the

• finite element method [14][15][16][17][18][19][20][21][22][23][24][25]. Using finite element simulation, Li et al. found that both loading curve and unloading curve at any depth can be generated from one indentation depth by scaling P ∝ h2 for the indentation tests of PMMA thin films with a Berkovich

• a vertical displacement on the rigid conical indenter. The contact between the indenter and the microsphere was frictionless. The calculation steps of nanoindentation simulation can be described as follows [1][2]: Construct an axisymmetric model of a microsphere and generate its finite element mesh

Mapping the local dielectric constant of a biological nanostructured system

• Wescley Walison Valeriano,
• Rodrigo Ribeiro Andrade,
• Juan Pablo Vasco,
• Angelo Malachias,
• Bernardo Ruegger Almeida Neves,
• Paulo Sergio Soares Guimarães and
• Wagner Nunes Rodrigues

Beilstein J. Nanotechnol. 2021, 12, 139–150, doi:10.3762/bjnano.12.11

• optical reflectance measurements and simulation, we were able to describe the origin of the strongly iridescent wing colors of this Amazonian rainforest damselfly. The method we demonstrate here should be useful for the study of other biological nanostructured systems. Keywords: dielectric constant

• reliable since there is a direct relation between the relative permittivity and the refractive index. Figure 8 shows the results of the simulation. On the left panels, the profile of the refraction index used to fit the optical reflectance are shown for each color region of the wing. As explained above

• correspond to the nanometric layers that constitute the wing. The dielectric constant of the peaks ranges between 8 and 9, and that of the valleys between 5 and 6. The red shadow on the black lines shows the standard deviation. Panels on the left show the refractive index profile used in the simulation and

Numerical analysis of vibration modes of a qPlus sensor with a long tip

• Kebei Chen,
• Zhenghui Liu,
• Yuchen Xie,
• Chunyu Zhang,
• Gengzhao Xu,
• Wentao Song and
• Ke Xu

Beilstein J. Nanotechnol. 2021, 12, 82–92, doi:10.3762/bjnano.12.7

• optimal tip size can be derived from the simulation results. Methods Model and parameters The model in the simulation is based on an MS1V-T1K-type quartz tuning fork used in our experiment (details will be described later). The dimensions of the MS1V-T1K quartz tuning fork, length L = 3423 µm, width W

• . The epoxy glue is defined as a cuboid in order to facilitate mesh generation and reduce calculation time, since it is not guaranteed to have a fixed geometry after curing. The glue thickness in the simulation is set to be the average glue thickness of the qPlus sensor used in our experiment. In this

• case, the volume of the glue in the simulation is approximately equal to the volume of the glue in the experiment. Figure 2d is a false-color representation of the total displacement levels. Warmer colors represent a larger displacement. All calculations were carried out using COMSOL Multiphysics

The role of gold atom concentration in the formation of Cu–Au nanoparticles from the gas phase

• Yuri Ya. Gafner,
• Svetlana L. Gafner,
• Darya A. Ryzkova and
• Andrey V. Nomoev

Beilstein J. Nanotechnol. 2021, 12, 72–81, doi:10.3762/bjnano.12.6

• composition; however, the size of the resulting particles varies significantly. To solve this issue, we studied the formation of Cu–Au nanoparticles with different chemical compositions from a gaseous medium using computer molecular dynamics (MD) simulation. The aim was to determine the effect of the

• MD simulation, it was concluded that an increase in the percentage of gold atoms in the initial vapor phase led to a decrease in the size of the synthesized nanoparticles. In addition, it was found that clusters with a size of more than 400–500 atoms, regardless of the chemical composition of the

• initial vapor phase, basically corresponded to a given target composition. Keywords: binary nanoparticles; computer simulation; copper; gold; molecular dynamics; Introduction The nanometer-sized Cu–Au compounds are being studied quite actively [1][2][3][4][5][6][7][8] because of their potential

Free and partially encapsulated manganese ferrite nanoparticles in multiwall carbon nanotubes

• Saja Al-Khabouri,
• Salim Al-Harthi,
• Toru Maekawa,
• Mohamed E. Elzain,
• Ashraf Al-Hinai,
• Ahmed D. Al-Rawas,
• Abbsher M. Gismelseed,
• Ali A. Yousif and
• Myo Tay Zar Myint

Beilstein J. Nanotechnol. 2020, 11, 1891–1904, doi:10.3762/bjnano.11.170

• , illustrated in the simulation of the O 1s peak in Figure 8e, can be assigned to three distinct oxygen species. The main peak at 530.1 eV corresponds to the crystal lattice oxygen O2−. The peak at 531.5 eV can be attributed to adsorbed molecular oxygen [24] and the third peak at 533.1 eV is common for C=O [44

Scanning transmission imaging in the helium ion microscope using a microchannel plate with a delay line detector

• Eduardo Serralta,
• Nico Klingner,
• Olivier De Castro,
• Michael Mousley,
• Santhana Eswara,
• Serge Duarte Pinto,
• Tom Wirtz and
• Gregor Hlawacek

Beilstein J. Nanotechnol. 2020, 11, 1854–1864, doi:10.3762/bjnano.11.167

• experimental contrast match qualitatively. A quantitative analysis shows relevant differences in the intensity levels of the regions. The relative intensity level of the area with the layer of silicon dioxide on top of the silicon nitride differs considerably in experiment and simulation. The signal in the

• upper left half and gold deposited on the lower left half. (b) TRIDYN simulation of the angular distribution of the transmitted beam. Helium ion microscopy images of the nanoporous polycrystalline silicon membrane. (a) SE image. (b) BF STIM image with polar angle θ < 3° and ϕ from 0 to 360°. Post

Molecular dynamics modeling of the influence forming process parameters on the structure and morphology of a superconducting spin valve

• Alexander Vakhrushev,
• Aleksey Fedotov,
• Vladimir Boian,
• Roman Morari and
• Anatolie Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1776–1788, doi:10.3762/bjnano.11.160

• molecular dynamics method using the many-particle potential of the modified embedded-atom method. In the calculation process the temperature was controlled using the Nose–Hoover thermostat. The simulation of the atomic nanolayer formation was performed by alternating the directional deposition of different

• properties of S/F nanosystem formation, it would be very useful to develop new integrated methods that combine theoretical modeling and experimental methods for analyzing the formation processes and properties of this class of functional nanomaterials and nanostructures. Here, computer simulation can

• reduces computational costs during simulation: where Cmin, Cmax are the parameters of the mutual influence of atoms, depending on their chemical types, and are set for each triple of atoms with numbers i, j, k. In Equation 11, rc is the distance at which the force field is cut off and fc(x) is a function

Imaging and milling resolution of light ion beams from helium ion microscopy and FIBs driven by liquid metal alloy ion sources

• Nico Klingner,
• Gregor Hlawacek,
• Paul Mazarov,
• Wolfgang Pilz,
• Fabian Meyer and
• Lothar Bischoff

Beilstein J. Nanotechnol. 2020, 11, 1742–1749, doi:10.3762/bjnano.11.156

• thickness. Milling membranes removes their support from one side and dangling bonds can lead to morphological changes making milling tests difficult to interpret. In metal layers of a few nanometers thickness, sputter redeposition can take place, which is not taken into account in our static SRIM simulation

• ), experimentally achieved trench width, and simulated minimum milling width (FWHM) for FIBs working with different ion species and technologies depending on the ion mass. The line serves as a guide to the eye. SRIM simulation [39] of the sputter profile from a 30 keV point-like beam in a gold substrate as a

Seebeck coefficient of silicon nanowire forests doped by thermal diffusion

• Shaimaa Elyamny,
• Elisabetta Dimaggio and
• Giovanni Pennelli

Beilstein J. Nanotechnol. 2020, 11, 1707–1713, doi:10.3762/bjnano.11.153

• the result of the simulation of the doping process. Hence, the Seebeck coefficient depends on the position in the nanowire. That is, S = S(n(x,y)), where (x,y) is a generic point in the cross section. Also the electrical conductivity depends on doping, that is, σ(x,y) = σ(n(x,y)) It has been estimated

The influence of an interfacial hBN layer on the fluorescence of an organic molecule

• Christine Brülke,
• Oliver Bauer and
• Moritz M. Sokolowski

Beilstein J. Nanotechnol. 2020, 11, 1663–1684, doi:10.3762/bjnano.11.149

Amorphized length and variability in phase-change memory line cells

• Nafisa Noor,
• Sadid Muneer,
• Raihan Sayeed Khan,
• Anna Gorbenko and
• Helena Silva

Beilstein J. Nanotechnol. 2020, 11, 1644–1654, doi:10.3762/bjnano.11.147

• simulation results obtained from the “simulation program with integrated circuit emphasis” (SPICE). The measured threshold voltage, and the drifted threshold field at that time are used to extract the amorphized length (Figure 1). A literature review of threshold switching in PCM Threshold switching is a

• of the amorphized region of length Lamorphized(2). At this point, the wire itself physically broke and the electrical connection was lost, possibly due to void formation in the middle of the cell (Figure 5c). Cell voltage and current extraction obtained via circuit simulation A SPICE simulation was

• rise and the re-amorphization is assumed to take place right after the peak of Vch3,4. Table 3 lists the melting and re-amorphization instances for the two re-amorphization events used in simulations. At the starting of the simulation, S1 is closed while S2 and S3 are kept open to use Ramorphous(before

Design of V-shaped cantilevers for enhanced multifrequency AFM measurements

• Mehrnoosh Damircheli and
• Babak Eslami

Beilstein J. Nanotechnol. 2020, 11, 1525–1541, doi:10.3762/bjnano.11.135

• an optimum rectangular cantilever. Two sets of bimodal AFM experiments are carried out on Au-PS and PS-LDPE (polystyrene and low-density polyethylene) samples to verify the simulation results. Keywords: bimodal AFM; optimization; soft matter; surface characterization; V-shaped cantilevers

• oscillation amplitude and phase response of the first and second bending eigenmodes, respectively. Results and Discussion Simulation analysis Figure 1 represents the schematic of the V-shaped cantilever where the length (L), width (b), thickness (t), width of each leg (), and the angle (2θ) are shown. We

• sample in air. R is the tip radius and Eeff is the effective elastic modulus between tip and sample. The material properties used in this simulation are shown in Table 1. The effects of length (L), overall width (b), the width of each leg () and the thickness (t) of the cantilever are optimized. In each

Adsorption and self-assembly of porphyrins on ultrathin CoO films on Ir(100)

• Feifei Xiang,
• Tobias Schmitt,
• Marco Raschmann and
• M. Alexander Schneider

Beilstein J. Nanotechnol. 2020, 11, 1516–1524, doi:10.3762/bjnano.11.134

• -hexagonal layer with lattice parameter a2BL CoO = 3.0–3.1 Å [18]. STM images of both films show the positions of the oxygen atoms as bright protrusions [20]. Computational Methods Non-magnetic ab initio calculations were performed using the Vienna Ab-initio Simulation Package (VASP) [32] employing the PBE

• corresponding STM simulation (Figure 7a, inset) agrees well with the symmetric dumbbell appearance in the experimental images. We also calculated the relaxed structure of 1 on 2BL CoO, where the molecule adopts a ruffled configuration [46]. We find that the maximum surface height difference between carbon atoms

• bent such that a bond between the cyano group and a Co ion of the substrate could be formed. However, the structure always relaxed into a state in which the N–Co distance exceeded 3.1 Å. While the STM simulation of that configuration shown in Figure 7d matches well with some of the molecules depicted

A wideband cryogenic microwave low-noise amplifier

• Boris I. Ivanov,
• Dmitri I. Volkhin,
• Ilya L. Novikov,
• Dmitri K. Pitsun,
• Dmitri O. Moskalev,
• Ilya A. Rodionov,
• Evgeni Il’ichev and
• Aleksey G. Vostretsov

Beilstein J. Nanotechnol. 2020, 11, 1484–1491, doi:10.3762/bjnano.11.131

• frequency of 12 GHz. The design was optimized for the frequency range from 6 to 12 GHz, which fits to most of modern qubit measurement setups. We used the available S-parameters of the transistor for the matching circuit design. From a circuit simulation with ideal components a minimal gain value of more

• the box in the operation frequency range. We did an electromagnetic simulation of the box and it showed us the absence of self-resonances in a frequency range from 1 to 12 GHz. The substrate was soldered directly to the brass box and SubMiniature version A (SMA) connectors with a specified frequency

Self-assembly and spectroscopic fingerprints of photoactive pyrenyl tectons on hBN/Cu(111)

• Domenik M. Zimmermann,
• Knud Seufert,
• Luka Ðorđević,
• Tobias Hoh,
• Sushobhan Joshi,
• Tomas Marangoni,
• Davide Bonifazi and
• Willi Auwärter

Beilstein J. Nanotechnol. 2020, 11, 1470–1483, doi:10.3762/bjnano.11.130

• polarizable continuum model (CPCM) was used to introduce nonspecific solvation effects. The spectra were generated either with GaussView 5 [94] or GaussSum [95], assuming a half-width of 0.15 eV for proper simulation. The IP and EA were determined as the vertical energy difference between the neutral molecule

Protruding hydrogen atoms as markers for the molecular orientation of a metallocene

• Linda Laflör,
• Michael Reichling and
• Philipp Rahe

Beilstein J. Nanotechnol. 2020, 11, 1432–1438, doi:10.3762/bjnano.11.127

• between experiment and simulation might also reflect a more general feature of repulsive mode imaging. While the tip–surface interaction force curves in the attractive region differ significantly from each other for different tip-terminating species, the force curves in the repulsive region are so steep

• staggered molecular conformation [22]. The protruding hydrogen atoms align in this geometry along a different direction with respect to geo 1 due to the partly staggered conformation of the Cp rings. The corresponding PPM image calculations with identical simulation parameters as before for a CO tip are

• frequency shift image. An inverted colour scale is used for the constant-height Δf NC-AFM data to match the topography appearance.) High-resolution NC-AFM imaging and simulation. Experimental and simulated frequency-shift images of a single molecular row along the direction (red arrows). Exemplary

On the frequency dependence of viscoelastic material characterization with intermittent-contact dynamic atomic force microscopy: avoiding mischaracterization across large frequency ranges

• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 1409–1418, doi:10.3762/bjnano.11.125

• (through simulation) the behavior of the dynamic AFM observables for hypothetical materials as a function of the frequency. We find this to be particularly important, as a review of the literature (including several of our own previous works), shows that dynamic AFM characterization has been routinely

• provides the simulation procedures and parameters). The amplitude curves (Figure 3a) exhibit the typical shape with bistability transitions [2]. We also notice that the amplitude values in the repulsive branch are larger for material 1 than for material 2. This is consistent with Figure 2, which shows that

• material 2 at 70 kHz, whereby material 2 appears much stiffer than material 1. Furthermore, the near absence of dissipation in the force curves of both materials supports the observed lack of phase sensitivity to material differences, in agreement with the literature [36][37]. For the simulation at 350 kHz

Transient coating of γ-Fe₂O₃ nanoparticles with glutamate for its delivery to and removal from brain nerve terminals

• Konstantin Paliienko,
• Artem Pastukhov,
• Michal Babič,
• Daniel Horák,
• Olga Vasylchenko and
• Tatiana Borisova

Beilstein J. Nanotechnol. 2020, 11, 1381–1393, doi:10.3762/bjnano.11.122

• mode v1.61. The laser correlation spectrometer was equipped with a multi-computing correlator type 7032 CE. Simulation of spatial structure of γ-Fe2O3 nanoparticles coated with blood plasma protein biocorona Simulations of biocorona formation at the surface of γ-Fe2O3 nanoparticles were performed using

• software for graphic-mathematical modeling, that is, a demonstration version of Diamond 4.5.3 (Crystal Impact GbR©) for the simulation of nanoparticle polycrystals, a demonstration version of LeadIT 2.3.2 (BioSolveIT GmbH©) to find the most probable binding sites between protein and nanoparticles, a free

• treatment with blood plasma were transferred into the standard salt solution. The mean nanoparticle size was 245 nm (Figure 8b), confirming that blood plasma prevented a significant increase in particle size due to presence of chelating agents in the standard salt solution. Simulation of the spatial

Atomic defect classification of the H–Si(100) surface through multi-mode scanning probe microscopy

• Jeremiah Croshaw,
• Thomas Dienel,
• Taleana Huff and
• Robert Wolkow

Beilstein J. Nanotechnol. 2020, 11, 1346–1360, doi:10.3762/bjnano.11.119

• terminations of different reactivity. Through this analysis we are able to identify unique electronic and structural signatures associated with the defects of each imaging mode. By combining these results with a simple probe particle simulation of the STHM and AFM images, we were able to confirm the underlying

Effect of localized helium ion irradiation on the performance of synthetic monolayer MoS₂ field-effect transistors

• Jakub Jadwiszczak,
• Pierce Maguire,
• Conor P. Cullen,
• Georg S. Duesberg and
• Hongzhou Zhang

Beilstein J. Nanotechnol. 2020, 11, 1329–1335, doi:10.3762/bjnano.11.117

• ) Simulation of the S vacancy yield generated as the He+ ion beam penetrates the device at the contact stack, indicating damage to the metal–semiconductor interface. Acknowledgements We acknowledge D. Keane for helpful discussions and D. Daly for assistance with the helium ion microscope. Funding The

Ultrasensitive detection of cadmium ions using a microcantilever-based piezoresistive sensor for groundwater

• Dinesh Rotake,
• Anand Darji and
• Nitin Kale

Beilstein J. Nanotechnol. 2020, 11, 1242–1253, doi:10.3762/bjnano.11.108

• mN/m, which is well below the stiffness required for BioMEMS applications (1000 mN/m [41][42]). COMSOL 5.3 software is used to perform design and simulation of the piezoresistive sensor to optimize the dimensions for better stiffness and sensitivity [43]. The fabricated piezoresistive sensor layer