Revealing the local crystallinity of single silicon core–shell nanowires using tip-enhanced Raman spectroscopy

• Marius van den Berg,
• Ardeshir Moeinian,
• Arne Kobald,
• Yu-Ting Chen,
• Anke Horneber,
• Steffen Strehle,
• Alfred J. Meixner and
• Dai Zhang

Beilstein J. Nanotechnol. 2020, 11, 1147–1156, doi:10.3762/bjnano.11.99

• , mainly due to a change in the c-Si Raman intensity. To quantify this tendency, the 16 × 16 spectra are processed by peak fitting and integration as described above. The intensity distribution of the a-Si Raman peak is plotted in Figure 3d and appears to be rather constant along the silicon wire. It

Extracting viscoelastic material parameters using an atomic force microscope and static force spectroscopy

• Cameron H. Parvini,
• M. A. S. R. Saadi and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 922–937, doi:10.3762/bjnano.11.77

• investigate different timescales of the mechanical response. This manuscript seeks to build upon our previous work and presents an approach to extracting useful linear viscoelastic information from AFM-SFS experiments. In addition, the basis for selecting and restricting the model parameters for fitting is

• necessary to describe and predict AFM tip–sample behavior accurately [9][10][11][12]. To this end, an appropriate viscoelastic model must be chosen (or derived) and subsequently specified for a geometry specific to AFM tip–sample interactions. The process of developing and fitting a viscoelastic model is

• discussion on practical applications of the methodology of Lopez and co-workers. Topics discussed here include the basis in theory, how to specify various material models for fitting, how to calculate relevant viscoelastic quantities, and importantly a discussion of where the extracted parameters are valid

Measurement of electrostatic tip–sample interactions by time-domain Kelvin probe force microscopy

• Christian Ritz,
• Tino Wagner and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2020, 11, 911–921, doi:10.3762/bjnano.11.76

• performed on Δftopo, where all electrostatic forces are compensated, including the static contribution . So far, recovering and fitting the Kelvin parabola is known as an open-loop technique, the so-called Kelvin probe force spectroscopy [22][23][24][25]. A real-time closed-loop technique has not been

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

• the bead (taken from one of the frames) and each frame of the video. The maximum in the respective correlation maps indicates the position of the bead. We find the position of the maxima with a resolution of a few nanometers by fitting a 2D parabola to the correlation maps in a limited range near the

• is the Boltzmann constant and T = 293 K is the temperature. Generally, the proportionalities kx(y) ∝ Ptrap and are found to hold (Ptrap is the power offered to the trap by the waveguides), in agreement with the above relation. By fitting 2D Gaussian functions to the 2D histograms, we obtain σΔx(Δy

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

• the E0(T) data as a function of T, where A1, B1 are constants having dimension of energy, and R0 is the exponential increment rate of E0. From the fitting, the value of R0 (1L) for WSe2 was found to be ≈0.0017/K, which is almost 3× < R0 (ML) and R0 (bulk), as shown by the comparative values in Table 2

• consequently (Figure 4e) vary widely in 1L, ML, and bulk WSe2, as nanostructure differences become the more dominant scattering source at low T. These dissimilarities in the decay in 1L, ML and bulk WSe2 at low T are characterized by fitting the results of Figure 4a, i.e., τ(T) for the mode, to the

Quantitative determination of the interaction potential between two surfaces using frequency-modulated atomic force microscopy

• Nicholas Chan,
• Carrie Lin,
• Tevis Jacobs,
• Robert W. Carpick and
• Philip Egberts

Beilstein J. Nanotechnol. 2020, 11, 729–739, doi:10.3762/bjnano.11.60

• , the best-fit parameters for Wadh and z0 are 0.0860 J/m2 and 0.55 nm, respectively. (b) An example of a square-rooted variance map produced using a least squares fitting technique to compare the experimental F(z) curves to LJ F(z) curves. (c, d) Histograms of the best-fit Wadh and z0 values

Observation of unexpected uniaxial magnetic anisotropy in La_2/3Sr_1/3MnO₃ films by a BaTiO₃ overlayer in an artificial multiferroic bilayer

• John E. Ordóñez,
• Lorena Marín,
• Luis A. Rodríguez,
• Pedro A. Algarabel,
• José A. Pardo,
• Roger Guzmán,
• Luis Morellón,
• César Magén,
• Etienne Snoeck,
• María E. Gómez and
• Manuel R. Ibarra

Beilstein J. Nanotechnol. 2020, 11, 651–661, doi:10.3762/bjnano.11.51

• uniaxial (ku) and biaxial (k1) anisotropy constants for the LSMO layer and BTO/LSMO bilayer grown on STO substrate. First, we determine the anisotropy energy ratios (ku/k1) by fitting the polar plots and determining the angles that minimize the general anisotropy energy equation. To separate ku/k1, we

Soybean-derived blue photoluminescent carbon dots

• Shanshan Wang,
• Wei Sun,
• Dong-sheng Yang and
• Fuqian Yang

Beilstein J. Nanotechnol. 2020, 11, 606–619, doi:10.3762/bjnano.11.48

• constants of Bi. The fitting curves are included in the corresponding figures. It is evident that Equation 1 is appropriate to describe the 440 and 459 nm PL-decay behavior of the HTC-CDs and the LA-CDs-10%, respectively. Table 1 lists the lifetimes and the corresponding contributions obtained from the

• curve fitting. It is evident that the PL decays of both the HTC-CDs and LA-CDs-10% consist of three rate processes with the fastest one, τ1, attributed to the intrinsic state of the CDs, and two slower processes, τ2 and τ3, attributed to the decays of the extrinsic states associated with the surface

• ” state, as shown schematically in Figure 6. From Figure 3, we note that the strongest emssion is at 440 nm for the HTC-CDs and 459 nm for the LA-CDs-10%. From Figure 6, we note that both peaks indeed can be fitted with a two-Gassian function, respectively. The fitting results reveal that the 440 nm

Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique

• Matthias Simolka,
• Hanno Kaess and
• Kaspar Andreas Friedrich

Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46

• [30][33][36][40], but the power law [29] or stretched exponential decay [41] functions are applied, too. The drawback of fits employing single exponential functions is the poor fitting quality compared to higher-order exponential functions or fitting functions with more parameters. Nevertheless, the

• additional fitting parameters increase the complexity of the interpretation and can lead to false conclusions [33][36]. Therefore, we used a single exponential decay function in form of Equation 2 for the fitting of the measurement signal with b = 1/τ. Luchkin et al. used ESM to study the changes in fresh

• voltage amplitude. However, the slope of the ESM signal is much smaller for the aged cathode, as compared to the fresh one. Fitting the ESM relaxation after the applied voltage pulse provides time constants which represent diffusion coefficients in the range of 2.5 × 10−14 m2 s−1. These values are in the

Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions

• Robert Kozioł,
• Marcin Łapiński,
• Paweł Syty,
• Damian Koszelow,
• Wojciech Sadowski,
• Józef E. Sienkiewicz and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2020, 11, 494–507, doi:10.3762/bjnano.11.40

• of 4 mm was used for analyzing the emitted photoelectrons. The binding energies were corrected using the background C 1s line (285.0 eV). XPS spectra were analyzed with the Casa-XPS software using a Shirley background subtraction and Gaussian–Lorentzian curves as fitting algorithm. The theoretical

• was taken from [15] and [16], respectively, and fitted to the Drude–Lorentz model [17] in the range of 287–1000 nm. The fitting error for Si was 1%/0.79% (real/imaginary part), and that for Ag was 0.12%/6.1%. These errors were calculated as the root mean square of the original curves and the fitted

Implementation of data-cube pump–probe KPFM on organic solar cells

• Benjamin Grévin,
• Olivier Bardagot and
• Renaud Demadrille

Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24

• exponents lower than 0.7 required for fitting of the spectroscopic curves (with the exception of the data in Figure 6f). These traps can be partially filled by applying a continuous white light background in addition to the pump pulse, which results in a significant reduction of the effective decay-time

An advanced structural characterization of templated meso-macroporous carbon monoliths by small- and wide-angle scattering techniques

• Felix M. Badaczewski,
• Marc O. Loeh,
• Torben Pfaff,
• Dirk Wallacher,
• Daniel Clemens and
• Bernd M. Smarsly

Beilstein J. Nanotechnol. 2020, 11, 310–322, doi:10.3762/bjnano.11.23

• . The degree of disorder in the graphene stacks can be determined by evaluating wide-angle X-ray (WAXS) and neutron (WANS) scattering data of turbostratic carbon materials. Several current evaluation methods for WAXS and WANS are based on the fitting of entire WAXS/WANS data sets using suitable

• inaccessible voids and sealed porosity hinders the penetration of the pore network, and the adsorption of DPX on the external surface leads to a larger scattering contrast, which in turn increases the overall intensity. The chord-length distributions g(r) (Figure 4B) were obtained by fitting the SANS data with

High-performance asymmetric supercapacitor made of NiMoO₄ nanorods@Co₃O₄ on a cellulose-based carbon aerogel

• Meixia Wang,
• Jing Zhang,
• Xibin Yi,
• Benxue Liu,
• Xinfu Zhao and
• Xiaochan Liu

Beilstein J. Nanotechnol. 2020, 11, 240–251, doi:10.3762/bjnano.11.18

• electrodes impede the diffusion less strongly, which is attributed to the faster transport of electrons and the charge transfer resistance (Rct). Fitting the electrochemical impedance spectroscopy (EIS) plots based on the equivalent circuit model (inset of Figure 6d), reveals a solution resistance (Rs) of

The different ways to chitosan/hyaluronic acid nanoparticles: templated vs direct complexation. Influence of particle preparation on morphology, cell uptake and silencing efficiency

• Arianna Gennari,
• Julio M. Rios de la Rosa,
• Erwin Hohn,
• Maria Pelliccia,
• Enrique Lallana,
• Roberto Donno,
• Annalisa Tirella and
• Nicola Tirelli

Beilstein J. Nanotechnol. 2019, 10, 2594–2608, doi:10.3762/bjnano.10.250

• -normal fit of the differential Rg distributions, in the second graph are the errors of the fitting. Protection of siRNA payload from enzymatic degradation. Left: PAGE analysis of entrapped siRNA after nanoparticle incubation with increasing concentrations of RNAse I, followed by quenching of nucleases

Synthesis and acetone sensing properties of ZnFe₂O₄/rGO gas sensors

• Kaidi Wu,
• Yifan Luo,
• Ying Li and
• Chao Zhang

Beilstein J. Nanotechnol. 2019, 10, 2516–2526, doi:10.3762/bjnano.10.242

• concentration at 200 °C and the corresponding fitting data. The results demonstrate that the response of the hollow spheres made of pure ZnFe2O4 and of ZnFe2O4/rGO with 0.5 wt % rGO are more intense at higher concentration of acetone. Moreover, it is obvious that the linear response of the 0.5 wt % ZnFe2O4/rGO

Abrupt elastic-to-plastic transition in pentagonal nanowires under bending

• Sergei Vlassov,
• Magnus Mets,
• Boris Polyakov,
• Jianjun Bian,
• Leonid Dorogin and
• Vahur Zadin

Beilstein J. Nanotechnol. 2019, 10, 2468–2476, doi:10.3762/bjnano.10.237

• mesh used in these simulations is described in previous work [29]. The yield strength values were obtained from the FEM NW model by fitting its profile to the experimentally bent profiles of Ag or Au NWs at the critical bending angle, before the abrupt transition to plastic deformation. MD simulations

Mobility of charge carriers in self-assembled monolayers

• Zhihua Fu,
• Tatjana Ladnorg,
• Hartmut Gliemann,
• Alexander Welle,
• Asif Bashir,
• Michael Rohwerder,
• Qiang Zhang,
• Björn Schüpbach,
• Andreas Terfort and
• Christof Wöll

Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235

• only along the (112) direction. The values Rmol and Rlat were determined by fitting the experimental resistance vs island diameter curve with the formula provided in Equation 1 (see Figure 2d). Note that the fit is not very good, indicating that the 1D model used for the derivation of Equation 1

Polyvinylpyrrolidone as additive for perovskite solar cells with water and isopropanol as solvents

• Chen Du,
• Shuo Wang,
• Xu Miao,
• Wenhai Sun,
• Yu Zhu,
• Chengyan Wang and
• Ruixin Ma

Beilstein J. Nanotechnol. 2019, 10, 2374–2382, doi:10.3762/bjnano.10.228

• simulator (Newport Oriel Sol3A Class AAA, 64023A Simulator), which was calibrated using a NREL standard Si solar cell. Electrochemical impedance spectroscopy (EIS) measurements were conducted by using an electrochemical workstation (CHI660d) (1 MHz to 100 Hz) and for fitting the Zview software was used. The

Atomic force acoustic microscopy reveals the influence of substrate stiffness and topography on cell behavior

• Yan Liu,
• Li Li,
• Xing Chen,
• Ying Wang,
• Meng-Nan Liu,
• Jin Yan,
• Liang Cao,
• Lu Wang and
• Zuo-Bin Wang

Beilstein J. Nanotechnol. 2019, 10, 2329–2337, doi:10.3762/bjnano.10.223

• using the same parameters. The Young’s moduli of the fabricated substrates were evaluated by fitting the force–distance curves with a Hertzian cone. A probe sensor (ContAl-G, Budget Sensors) was used in the force modulation mode for measuring the Young’s moduli. The cantilever spring constant was 0.2 N

Ultrathin Ni_1−xCo_xS₂ nanoflakes as high energy density electrode materials for asymmetric supercapacitors

• Xiaoxiang Wang,
• Teng Wang,
• Rusen Zhou,
• Lijuan Fan,
• Shengli Zhang,
• Feng Yu,
• Tuquabo Tesfamichael,
• Liwei Su and
• Hongxia Wang

Beilstein J. Nanotechnol. 2019, 10, 2207–2216, doi:10.3762/bjnano.10.213

• supported by aluminium SEM sample stages. Chemical composition and valence states of each element in the material are further confirmed by using XPS. The high-resolution XPS spectra confirm the existence of nickel, cobalt, and sulfur. After fitting the XPS with the Gaussian method, the HRXPS spectrum of Ni

Improved adsorption and degradation performance by S-doping of (001)-TiO₂

• Xiao-Yu Sun,
• Xian Zhang,
• Xiao Sun,
• Ni-Xian Qian,
• Min Wang and
• Yong-Qing Ma

Beilstein J. Nanotechnol. 2019, 10, 2116–2127, doi:10.3762/bjnano.10.206

• performed for the samples 1-S0, 1-S2 and 1-S5. The results are not shown here because the S element was not detected possibly be due to the small amount of S atoms doped into the samples or adsorbed at the TiO2 surface [39]. By fitting the XP spectra of Ti 2p and O 1s we deduce that the CSs correspond to

Microbubbles decorated with dendronized magnetic nanoparticles for biomedical imaging: effective stabilization via fluorous interactions

• Da Shi,
• Justine Wallyn,
• Dinh-Vu Nguyen,
• Francis Perton,
• Delphine Felder-Flesch,
• Sylvie Bégin-Colin,
• Mounir Maaloum and
• Marie Pierre Krafft

Beilstein J. Nanotechnol. 2019, 10, 2103–2115, doi:10.3762/bjnano.10.205

• or not. The interfacial tension at equilibrium (σeq) of the dendronized IONP dispersions and characteristic times of adsorption (τ) of the latter for various Fe concentrations are collected in Table 1. The τ values were determined by fitting the adsorption profiles (Figure 3) to an exponential decay

Green and scalable synthesis of nanocrystalline kuramite

• Andrea Giaccherini,
• Giuseppe Cucinotta,
• Stefano Martinuzzi,
• Enrico Berretti,
• Werner Oberhauser,
• Alessandro Lavacchi,
• Giovanni Orazio Lepore,
• Giordano Montegrossi,
• Maurizio Romanelli,
• Antonio De Luca,
• Massimo Innocenti,
• Vanni Moggi Cecchi,
• Matteo Mannini,
• Antonella Buccianti and
• Francesco Di Benedetto

Beilstein J. Nanotechnol. 2019, 10, 2073–2083, doi:10.3762/bjnano.10.202

• each sample, but sample S2 shows an additional very pronounced shoulder at 350 cm−1. Figure 4a,c shows the results of a nonlinear fitting process carried out with two Lorentzian peaks for samples S1 and S3 (adding further Lorentzian components to the spectra did not lead to an reduction in the R factor

• with Sn in tetrahedral coordination with S atoms in a CTS structure. Although the EXAFS signal is characterized by an almost single-frequency oscillation, the fitting procedure with the sole Sn–S path leads to a residual signal with a well-defined oscillation period. Most of the residual signal was

Synthesis of highly active ETS-10-based titanosilicate for heterogeneously catalyzed transesterification of triglycerides

• Muhammad A. Zaheer,
• David Poppitz,
• Khavar Feyzullayeva,
• Marianne Wenzel,
• Jörg Matysik,
• Radomir Ljupkovic,
• Aleksandra Zarubica,
• Alexander A. Karavaev,
• Andreas Pöppl,
• Roger Gläser and
• Muslim Dvoyashkin

Beilstein J. Nanotechnol. 2019, 10, 2039–2061, doi:10.3762/bjnano.10.200

• using Equation 2 and a sum of three diffusion modes. The result of the fitting procedure is presented in Table 4. In the utilized oversaturated sample, that is, when the bulk excess was present, one component (the fastest amongst all others and labelled as “1”) shall be assigned to the diffusion of the

• bulk triolein. This value was also measured in a separate experiment with triolein only, resulting in 2.0 × 10−10 m2 s−1 (see the dashed line in Figure 16) and was fixed during the fitting procedure. The second mode “2” (with diffusivity 2.9 × 10−11 m2 s−1) presumably originates from the diffusion

Magnetic properties of biofunctionalized iron oxide nanoparticles as magnetic resonance imaging contrast agents

• Natalia E. Gervits,
• Andrey A. Gippius,
• Alexey V. Tkachev,
• Evgeniy I. Demikhov,
• Sergey S. Starchikov,
• Igor S. Lyubutin,
• Alexander L. Vasiliev,
• Vladimir P. Chekhonin,
• Maxim A. Abakumov,
• Alevtina S. Semkina and
• Alexander G. Mazhuga

Beilstein J. Nanotechnol. 2019, 10, 1964–1972, doi:10.3762/bjnano.10.193

• selected in Figure 2 are very similar (a = 0.84 nm), and hence magnetite (Fe3O4) and disordered maghemite γ-Fe2O3 compounds cannot be resolved by HRTEM in such images. The Raman spectrum of the uncoated nanoparticles is shown in Figure 4, and the fitting of the peaks in the frequency region up to 950 cm−1

• was used in our ZF-NMR experiment. XRD patterns of coated and uncoated magnetic nanoparticles. HRTEM images of uncoated (a) and HSA-functionalized samples (b). The particle size distribution estimated from the HRTEM images in Figure 2. Raman spectrum of uncoated nanoparticles. Fitting of the peaks in