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

• piezoelectric sensor. Ti3C2 MXene and Ag NWs maintain the good conductivity of the electrode and avoid possible short-circuit problems occurring after magnetron sputtering. Also, a stable flexibility of the structure is maintained. GR is added with six different mass fractions, that is, 0, 0.2, 0.4, 0.6, 0.8

A self-powered, flexible ultra-thin Si/ZnO nanowire photodetector as full-spectrum optical sensor and pyroelectric nanogenerator

• Liang Chen,
• Jianqi Dong,
• Miao He and
• Xingfu Wang

Beilstein J. Nanotechnol. 2020, 11, 1623–1630, doi:10.3762/bjnano.11.145

• etching. More specifically, a 500 μm p-type high conductivity Si substrate was dipped into potassium hydrate (KOH) solution with a concentration of 50% at 130 °C for 6–8 h. Then, the obtained 45 μm p-Si was washed with acetone, isopropanol, and deionized water. Secondly, a thin ZnO seed layer was

PTCDA adsorption on CaF₂ thin films

• Philipp Rahe

Beilstein J. Nanotechnol. 2020, 11, 1615–1622, doi:10.3762/bjnano.11.144

• name two examples, the conductivity through a NaCl bilayer still dominates the conductivity along a molecular wire [4] and only the usage of thick NaCl films has enabled charge stability of single molecules [5]. A particularly well-studied case of surface-specific molecular properties is the adsorption

• , coupling to defects within the CaF1 layer, or charge transfer into the LUMO. Imaging at a positive sample bias of +1.5 V was performed in constant-height mode as the reduced sample conductivity at positive bias impeded operation in constant-current mode. Still, conductivity through PTCDA molecules is also

Detecting stable adsorbates of (1S)-camphor on Cu(111) with Bayesian optimization

• Jari Järvi,
• Patrick Rinke and
• Milica Todorović

Beilstein J. Nanotechnol. 2020, 11, 1577–1589, doi:10.3762/bjnano.11.140

• been applied in detecting molecular conformers [25] and adsorbate structures [26][27], in identifying stable molecular compounds [28], and in discovering materials with low thermal hysteresis [29] or thermal conductivity [30]. Typically, previous studies have employed customized material-specific

Electrokinetic characterization of synthetic protein nanoparticles

• Daniel F. Quevedo,
• Cody J. Lentz,
• Adriana Coll de Peña,
• Yazmin Hernandez,
• Nahal Habibi,
• Rikako Miki,
• Joerg Lahann and
• Blanca H. Lapizco-Encinas

Beilstein J. Nanotechnol. 2020, 11, 1556–1567, doi:10.3762/bjnano.11.138

• micro- and the nanoscale [29][39][40][41] as well as the sorting of protein nanocrystals with a streaming insulator-based DEP technique [42][43][44]. The Swami and Chou groups have studied protein particle enrichment in high-conductivity media employing devices with nanoscale gaps and reported both

• low-conductivity EK media used in the subsequent experiments. To test the potential of using EK microfluidics as a high-throughput SPNP purification technique, our particles had to be fluorescently labeled to be visualized with a fluorescence microscope. To accomplish this, we incorporated

• the particles had a similar shape and were indistinguishable from each other when visualized using SEM. While surprising, considering the different isoelectric points, the lack of a difference in ζp value was likely due to the low-conductivity suspension media used. Conversely, when the particles were

Helium ion microscope – secondary ion mass spectrometry for geological materials

• Matthew R. Ball,
• Richard J. M. Taylor,
• Joshua F. Einsle,
• Fouzia Khanom,
• Christelle Guillermier and
• Richard J. Harrison

Beilstein J. Nanotechnol. 2020, 11, 1504–1515, doi:10.3762/bjnano.11.133

• conductivity across the sample surface, it can dampen the signal to a point where some elements fall below the background noise level. However, the primary beam is not designed for the rapid removal of material and if the applied coating is thicker than 5–10 nm, its removal can take an unreasonable amount of

One-step synthesis of carbon-supported electrocatalysts

• Sebastian Tigges,
• Nicolas Wöhrl,
• Ivan Radev,
• Ulrich Hagemann,
• Markus Heidelmann,
• Thai Binh Nguyen,
• Stanislav Gorelkov,
• Stephan Schulz and
• Axel Lorke

Beilstein J. Nanotechnol. 2020, 11, 1419–1431, doi:10.3762/bjnano.11.126

• discussed in the following. Traditional multistep synthesis methods for Pt/C catalysts use supports, which are partially graphitized for reaching the required high electrical conductivity and durability. Therefore, the support surface is characterized by a low density of binding sites for anchoring Pt-NP

• , on which the Pt-NPs can then easily diffuse. Hence, these supports often require additional functionalization steps for avoiding metal particle agglomeration, which reduces the electrical conductivity and durability of the support. In sharp contrast, the one-step synthesis of Pt/CNW presented herein

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

• of glutamate and aspartate by chemically modified γ-Fe2O3 nanoparticles. The glutamate and aspartate solutions were prepared in HNO3 at pH 3.0 and under nitrogen flux. The chemisorption was investigated in acidic medium by measuring the changes in the conductivity of the solution during addition of

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

• , with the charge-induced band bending enhancing the conductivity locally around its location, as seen in Figure 2b-2. In the constant-height STM frame in Figure 2b-3 a reduction of current due to the charge-induced band bending is again observed, along with a distortion of the density of states of the

• , as indicated by the height scales in the constant current STM images in Figure 2k-1,2. In the constant height STM image of Figure 2k-3, it shows only a slight increase in conductivity localized to a single atomic site, suggesting that the Si atom on one side of the dimer is perhaps replaced by this

• ). STM imaging in Figure 2c-1 and Figure 2c-3 show an enhancement in conductivity at dimers neighbouring the reconstruction and a reduction above the H2Si atoms. Figure 2c-2 shows a dimer row that has been formed between two of the regular dimer rows, with Figure 2c-3 also highlighting this realignment

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

• Technology, Universität der Bundeswehr München, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany 10.3762/bjnano.11.117 Abstract Helium ion irradiation is a known method of tuning the electrical conductivity and charge carrier mobility of novel two-dimensional semiconductors. Here, we report a systematic

• cm−2 [13][14][15][16][17], as well as good electrical conductivity for up to approx. 1018 ions cm−2 [9][10][18]. Sulfur vacancies (SVs) and the formation of a dislocation–divacancy complex can lead to significant n-doping in MoS2 [19], which shifts the threshold voltage (Vth) of the FET to higher

Structural and electronic properties of SnO₂ doped with non-metal elements

• Jianyuan Yu,
• Yingeng Wang,
• Yan Huang,
• Xiuwen Wang,
• Jing Guo,
• Jingkai Yang and
• Hongli Zhao

Beilstein J. Nanotechnol. 2020, 11, 1321–1328, doi:10.3762/bjnano.11.116

• is that F-doped SnO2 has the lowest defect binding energy. The doping with B and S introduced additional defect energy levels within the forbidden bandgap, which improved the crystal conductivity. The Fermi level shifts up due to the doping with B, F, and S, while the Fermi level of SnO2 doped with C

• (substituting O) can effectively increase the carrier concentration and improve the conductivity. Majumder successfully prepared SnO2:F thin films using spray pyrolysis with SnF2 as the precursor. By adjusting the concentration of the precursor solution, doped SnO2 films with different properties were obtained

• conduction band. The electronic structure including the energy band structure, total density of states and partial wave state density of the doped system are shown in Figure 2. For SnO2, the Fermi energy level is at the top of the valence band, indicating that the conductivity of SnO2 is low. The conduction

Magnetohydrodynamic stagnation point on a Casson nanofluid flow over a radially stretching sheet

• Ganji Narender,
• Kamatam Govardhan and
• Gobburu Sreedhar Sarma

Beilstein J. Nanotechnol. 2020, 11, 1303–1315, doi:10.3762/bjnano.11.114

• generation, DT is the thermophoresis diffusion coefficient, σ is the electrical conductivity, β represents the Casson fluid parameter, and T represents the nanofluid temperature. The following similarity variables are taken into consideration: Finally, the ODEs describing the proposed flow problem can be

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

• specific surface area. The increase in the specific surface area of the electrode due to increased porosity facilitates ion transportation, which increases the conductivity of monolithic electrodes [24][25][26]. Although the porous carbon nanofibers have a high specific surface area, their low electrical

• conductivity impedes their use in high-power-density supercapacitors. Therefore, by adding high-performance conductive materials one can enhance the electrochemical performance of carbon nanofibers. Experiments have shown that by introducing graphene into the carbon matrix, various mechanical and

• electrical conductivity and good biocompatibility [28][29][30]. Studies have indicated that graphene still maintains an excellent charge/discharge performance at an electrochemical scan rate of almost 250 mV·s−1 [31] and has an excellent cycle performance and fast charge/discharge characteristics [32

High permittivity, breakdown strength, and energy storage density of polythiophene-encapsulated BaTiO₃ nanoparticles

• Adnanullah Khan,
• Amir Habib and
• Adeel Afzal

Beilstein J. Nanotechnol. 2020, 11, 1190–1197, doi:10.3762/bjnano.11.103

• exhibit irregular surface profile, which confirms the occurrence of sub-micrometer clusters and nanoscale particles on the surface. The permittivity or dielectric constant (ε′), loss tangent (tan δ), dielectric loss (ε″), and ac conductivity (σac) of the synthesized materials are measured as a function of

• resistivity of grain boundaries, more energy is required for electron hopping, thus, increasing the loss [27][28]. In the high frequency region that corresponds to the higher conductivity, energy required for the hopping of electrons is less and therefore, the loss decreases [27][28]. Dielectric loss is an

• conductivity of BTO and core–shell BTO-PTh nanoparticles. The ac conductivity as a function of the frequency is shown in Figure 6d. It is observed that BTO-PTh nanoparticles have a lower ac conductivity than BTO, and the ac conductivity increases linearly with the frequency of the applied field. At lower

Nonadiabatic superconductivity in a Li-intercalated hexagonal boron nitride bilayer

• Kamila A. Szewczyk,
• Izabela A. Domagalska,
• Artur P. Durajski and
• Radosław Szczęśniak

Beilstein J. Nanotechnol. 2020, 11, 1178–1189, doi:10.3762/bjnano.11.102

• result is radically different from the data obtained for graphene/SiO2 [33]. In addition, hBN monolayers exhibit a high temperature stability, a low dielectric constant (ε = 3–4), and a high thermal conductivity [34]. The band gap of hBN is about 5.9 eV [35]. Furthermore, which is also important, hBN is

Thermophoretic tweezers for single nanoparticle manipulation

• Jošt Stergar and
• Natan Osterman

Beilstein J. Nanotechnol. 2020, 11, 1126–1133, doi:10.3762/bjnano.11.97

•  1b,c). Temperature measurements are performed using the temperature-dependent fluorescence of sulforhodamine B (Radiant dyes Chemie), which is calibrated in an independent measurement (accuracy ±2 K). Since the sapphire glass with a high thermal conductivity helps cooling the thin sample film, the

A few-layer graphene/chlorin e6 hybrid nanomaterial and its application in photodynamic therapy against Candida albicans

• Selene Acosta,
• Carlos Moreno-Aguilar,
• Dania Hernández-Sánchez,
• Beatriz Morales-Cruzado,
• Erick Sarmiento-Gomez,
• Carla Bittencourt,
• Luis Octavio Sánchez-Vargas and
• Mildred Quintana

Beilstein J. Nanotechnol. 2020, 11, 1054–1061, doi:10.3762/bjnano.11.90

• , due to their excellent physical and chemical properties (e.g., high surface area, excellent thermal and electric conductivity, high mechanical strength)[19][20][21]. Examples of graphene nanomaterials include single-layer graphene, few-layer graphene (FLG), graphene oxide (GO), and the reduced form of

• GO (rGO) [22]. GO and rGO have been conjugated to several photosensitizers to enhance their performance in PDT [15][17][23][24][25]. However, for enhancing the characteristics of a Ps, the properties of graphene, such as electrical conductivity and chemical stability are very important, and these

Excitonic and electronic transitions in Me–Sb₂Se₃ structures

• Nicolae N. Syrbu,
• Victor V. Zalamai,
• Ivan G. Stamov and
• Stepan I. Beril

Beilstein J. Nanotechnol. 2020, 11, 1045–1053, doi:10.3762/bjnano.11.89

• that is characteristic of the conductivity hopping mechanism which in turn is independent of the metal type and the deposition method used. The photocurrent increases when the energy of the photons increases in the Schottky barriers when the transparent contacts are illuminated. The structures with the

A new photodetector structure based on graphene nanomeshes: an ab initio study

• Babak Sakkaki,
• Hassan Rasooli Saghai,
• Ghafar Darvish and
• Mehdi Khatir

Beilstein J. Nanotechnol. 2020, 11, 1036–1044, doi:10.3762/bjnano.11.88

• among experimental and theoretical researchers. Electrical properties such as a charge mobility in the range of 105 cm2·V−1·s−1, a minimum conductivity at the Dirac point of 4e2/πh (at low temperature), and remarkable optical properties such as linear dispersion of the Dirac electrons make broadband

• particular, photodetectors based on graphene will have a large dark current due to the conductivity of graphene even without incident photons [2]. An energy gap in the band structure of graphene can be created using quantum confinement effects via creating graphene nanoribbons (GNRs) with a width of

• . According to our calculations, the bandgap of A4Z6-6 and A4Z6-24 is 0.49 and 0.92 eV, respectively. The Fermi level in A4Z6-6 is closer to the conduction band, which increases the distribution of carriers and the conductivity of this material. At the end of the paper, we compare our detector to some state

Gas-sensing features of nanostructured tellurium thin films

• Dumitru Tsiulyanu

Beilstein J. Nanotechnol. 2020, 11, 1010–1018, doi:10.3762/bjnano.11.85

• different operating temperatures with respect to scanning electron microscopy and X-ray diffraction analyses. It was shown that both types of films interacted with nitrogen dioxide, which resulted in a decrease of electrical conductivity. The gas sensitivity, as well as the response and recovery times

• with an approximate average size of 100 nm. Assuming the neutrality of the Au/Te contacts, the electrical conductivity of the film is mainly controlled by the bulk, surface and grain boundary resistances. On the other hand, due to the peculiarities of chalcogens and chalcogenide materials [1][30], a

Effect of magnetic field, heat generation and absorption on nanofluid flow over a nonlinear stretching sheet

• Santoshi Misra and
• Govardhan Kamatam

Beilstein J. Nanotechnol. 2020, 11, 976–990, doi:10.3762/bjnano.11.82

• thermal conductivity and convective heat transfer performance of base fluids such as water, ethylene, glycol, etc. This takes place due to the intense and rigorous distribution of nanoparticle Brownian motion within the base fluid, thus enhancing the uniformity, conductance and properties which have paved

• expansion coefficient, ρp is the particle density, σ denotes the nanofluid electrical conductivity, B0 denotes the magnetic induction, vw denotes the suction/injection velocity and Q0 (Q) denotes the heat generation (absorption) coefficient. us in Equation 8 represents the slip velocity, given as which is

Band tail state related photoluminescence and photoresponse of ZnMgO solid solution nanostructured films

• Vadim Morari,
• Aida Pantazi,
• Nicolai Curmei,
• Vitalie Postolache,
• Emil V. Rusu,
• Marius Enachescu,
• Ion M. Tiginyanu and
• Veaceslav V. Ursaki

Beilstein J. Nanotechnol. 2020, 11, 899–910, doi:10.3762/bjnano.11.75

• different numbers of technological steps and the different temperature of the substrate during the deposition processes. In our opinion, the higher resistivity of the films prepared by spin coating as compared to those obtained by spray pyrolysis indicates a higher degree of conductivity compensation, due

• amplitude of potential fluctuations is determined by the degree of doping and conductivity compensation. In porous semiconductors the amplitude is determined by the degree of porosity, while it is a function of local fluctuations of the composition in solid solutions, including ZnMgO. The observation of the

A Josephson junction based on a highly disordered superconductor/low-resistivity normal metal bilayer

• Pavel M. Marychev and
• Denis Yu. Vodolazov

Beilstein J. Nanotechnol. 2020, 11, 858–865, doi:10.3762/bjnano.11.71

• suppressed. It allows us to use normal-state heat conductivity both in the SN and the S region in the heat conductance equation for the calculation of δTe. This is in contrast to S-N-S and S’-S-S’ junctions where heat conductivity is suppressed in the superconducting banks. In our model Joule dissipation is

• : where is the electron heat conductivity of the S layer in the normal state, and N(0) is the one-spin density of states on the Fermi level, is the thermal healing length, β = [γτesc 450ζ(5)T/[τ0π4Tc0], ζ(5) ≈ 1.03, τesc is the escape time of nonequilibrium phonons to the substrate, γ = 8π2Ce(Tc0)/Cp(Tc0

Light–matter interactions in two-dimensional layered WSe₂ for gauging evolution of phonon dynamics

• Avra S. Bandyopadhyay,
• Chandan Biswas and
• Anupama B. Kaul

Beilstein J. Nanotechnol. 2020, 11, 782–797, doi:10.3762/bjnano.11.63

• external stimuli. For example, external radiation could be in the form of heat or optical energy, which also directly influences properties such as the electronic and optoelectronic transport and the thermal conductivity of the material. In this work, we have conducted an in-depth analysis of the phonon

• dependence of the Raman shifts in 2D TMDCs such as MoS2 [20][21][22][23][24], and WS2 [25][26] have been extensively studied over a wide temperature range from which properties such as thermal conductivity was deciphered [23][27]. On the contrary, the temperature-dependent Raman analysis of WSe2 is rather

• phonon density increases as T3, while in a quantum confined system such as the 1L case, the phonon density is not as strong a function of T. This also has a direct influence on the thermal conductivity of quantum-confined 1D structures where the thermal conductivity should be high and not vary

Nickel nanoparticles supported on a covalent triazine framework as electrocatalyst for oxygen evolution reaction and oxygen reduction reactions

• Secil Öztürk,
• Yu-Xuan Xiao,
• Dennis Dietrich,
• Beatriz Giesen,
• Juri Barthel,
• Jie Ying,
• Xiao-Yu Yang and
• Christoph Janiak

Beilstein J. Nanotechnol. 2020, 11, 770–781, doi:10.3762/bjnano.11.62

• of nickel into the voids of CTF-1 (Table S2, Supporting Information File 1). Still, surface area and porosity of the Ni/CTF-1 composites are high, which are important features. It is accepted that conductivity plays a more important role, yet high surface area and porosity are known to enhance the

• exposure of active sites and to improve the ion and charge transfer through nanochannels together with the electron-conductive medium [46]. Here, the increase of conductivity and surface area from CTF-1-400 to CTF-1-600 go in the same direction and cannot be differentiated regarding their role in improving

• admixture of Ni species with low activity in the composite materials. The better OER performance of CTF-1-600 over the CTF-1-400 materials is attributed to the better conductivity of the former (as given by the Nyquist plot in Figure 7) and its faster ion and charge transfer together with its higher