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

• the C-matrix and the Pt-NPs during the process. The carbon support consists of carbon nanowalls (CNWs), which are vertically aligned, multilayer graphene nanosheets [18][19]. The morphology of the CNWs, the amount of platinum loading as well as the size of the platinum NPs can be precisely adjusted

• by cyclic voltammetry (CV) measurements. Results and Discussion One-step synthesis and its product Platinum acetylacetonate was used as a single-source precursor for the deposition of Pt-NPs embedded in the supporting CNW matrix. CNWs are vertically aligned, graphitic, multilayer carbon sheets, which

• provide not only a high surface area but also a decent electrical conductance, thus acting as an ideal support material for electrocatalysis [18][19]. The route for the simultaneous growth of both the Pt precipitates and the carbon matrix (CNWs), which merge to form the catalytic hybrid material, is

Superconductor–insulator transition in capacitively coupled superconducting nanowires

• Alex Latyshev,
• Andrew G. Semenov and
• Andrei D. Zaikin

Beilstein J. Nanotechnol. 2020, 11, 1402–1408, doi:10.3762/bjnano.11.124

• , and Cij denote the matrix elements of the inductance and capacitance matrices and Φ0 = π/e is the superconducting flux quantum. Note that for the sake of simplicity here and below we set Planck constant ℏ, speed of light, c, and Boltzmann constant, kB, equal to unity. The Hamiltonian (Equation 1) is

• routinely divide the χ-variables into fast and slow components, , where Setting δΛ/Λ ≪ 1, expanding in the fast field components and integrating them out we proceed perturbatively in y1,2 and observe that in order to account for the leading order corrections it is necessary to evaluate the matrix Green

• function at coincident points which reads where and is the velocity matrix for plasmon modes propagating along the wires. The matrix has the form where is the velocity of the Mooij–Schön modes in the ith wire in the absence of capacitive coupling between the wires, i.e. for Cm → 0. Following the

Analysis of catalyst surface wetting: the early stage of epitaxial germanium nanowire growth

• Owen C. Ernst,
• Felix Lange,
• David Uebel,
• Thomas Teubner and
• Torsten Boeck

Beilstein J. Nanotechnol. 2020, 11, 1371–1380, doi:10.3762/bjnano.11.121

• silicon nanotip [22] surrounded by a silicon oxide matrix is shown in Figure 4e and Figure 4f. A gold droplet is formed at the silicon tip during gold deposition (Figure 4e). After germanium deposition, the gold droplet at the silicon tip forms a single in-plane nanowire at the surface of the silicon

• oxide matrix (Figure 4f). Discussion This work had three major aims and the first one was to compare between three different interfacial energy models and how they agreed with the experimental results (Table 1). The second aim was to investigate the wetting behaviour of gold when deposited onto silicon

• nanowire is clearly visible. (e) Top-view image of a single gold nanodroplet at a silicon tip in a silicon oxide matrix. As it can be seen, the droplet sits at only one side of the silicon tip. (f) Image of the sample shown in (e) after germanium deposition. The gold droplet catalysed the growth of a

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

• 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

• electrochemical properties of the original carbon matrix can be significantly improved [27]. The perfect crystalline graphene has an ideal two-dimensional crystal structure composed of a stable regular hexagonal lattice, which has an excellent theoretical specific surface area, increased electron mobility, high

Role of redox-active axial ligands of metal porphyrins adsorbed at solid–liquid interfaces in a liquid-STM setup

• Thomas Habets,
• Sylvia Speller and
• Johannes A. A. W. Elemans

Beilstein J. Nanotechnol. 2020, 11, 1264–1271, doi:10.3762/bjnano.11.110

• spectra were measured in reflective mode with dithranol as a matrix on a Bruker Microflex LRF MALDI-TOF mass spectrometer (Bruker, Billerica, MA, USA). UV–vis spectra were recorded on a Varian Cary 50 UV–vis spectrophotometer. Syntheses Synthesis of MnTUPOCl and CuTUP Compounds MnTUPCl [7] and CuTUP [10

Influence of the magnetic nanoparticle coating on the magnetic relaxation time

• Mihaela Osaci and
• Matteo Cacciola

Beilstein J. Nanotechnol. 2020, 11, 1207–1216, doi:10.3762/bjnano.11.105

• synthesized in small dimensions, which ensures low toxicity and the possibility for easy surface functionalization. A common method for synthesising iron-oxide nanoparticles includes chemical co-precipitation, which involves the simultaneous precipitation of magnetic nanoparticles and a solid matrix through a

• sol–gel process, yielding metal-oxide nanoparticles dispersed in a mesoporous matrix. [5]. Other methods used for synthesising these nanoparticles include modifications of the sol–gel method. These methods involve supercritical conditions, such as ethyl alcohol and alkaline co-precipitation, and an

• thickness of the surfactant coating layer and the density of the polymer surface layer influence both the Néel relaxation time and the effective magnetic relaxation time in a system consisting of magnetic nanoparticles suspended in a liquid matrix. To simulate the self-organization of the colloidal

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

• ][10], which are largely attributed to the interphase inhomogeneity, poor distribution, and agglomeration of BTO nanoparticles in the polymer matrix. You et al. [10] observed an increase in the permittivity (from 4 to 14) of poly(arylene ether nitrile) filled with 40 wt % polyaniline-functional-BTO

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

• the equation for the wave function renormalization factor we obtained the expression in Equation 13. The explicit expressions for the kernels are given below: In Equation 14–Equation 20, gq means the electron–phonon matrix element, ωq represents the phonon energy, and εk is the electron band energy

Hybridization vs decoupling: influence of an h-BN interlayer on the physical properties of a lander-type molecule on Ni(111)

• Maximilian Schaal,
• Takumi Aihara,
• Marco Gruenewald,
• Felix Otto,
• Jari Domke,
• Roman Forker,
• Hiroyuki Yoshida and
• Torsten Fritz

Beilstein J. Nanotechnol. 2020, 11, 1168–1177, doi:10.3762/bjnano.11.101

• corresponding epitaxy matrix as well as the lattice parameters are summarized in Table 1. We used the projection method proposed by Forker et al. to identify possible coincidences of the adsorbate and the substrate lattice [35]. We find more than one possible coincidence within the error margin of the epitaxy

• matrix. However, we can exclude higher-order commensurate (HOC) and point-on-line (POL) coincidences with a substrate order lower than four. By tendency, the higher the substrate order, the lower is the epitaxial energy gain and therefore the probability of the coincidence [35][36]. In the case of highly

• vector is labeled with δ. Before each epitaxy matrix a prefactor along with its margin of error indicates the absolute scaling uncertainty of the analyzed LEED image. Please note that the epitaxy matrix of DBP on Au(111) and on Ag(111) deviates from the matrix of DBP on h-BN/Ni(111) because of different

Applications of superparamagnetic iron oxide nanoparticles in drug and therapeutic delivery, and biotechnological advancements

• Maria Suciu,
• Corina M. Ionescu,
• Alexandra Ciorita,
• Septimiu C. Tripon,
• Dragos Nica,
• Hani Al-Salami and
• Lucian Barbu-Tudoran

Beilstein J. Nanotechnol. 2020, 11, 1092–1109, doi:10.3762/bjnano.11.94

Plant growth regulation by seed coating with films of alginate and auxin-intercalated layered double hydroxides

• Vander A. de Castro,
• Valber G. O. Duarte,
• Danúbia A. C. Nobre,
• Geraldo H. Silva,
• Vera R. L. Constantino,
• Frederico G. Pinto,
• Willian R. Macedo and
• Jairo Tronto

Beilstein J. Nanotechnol. 2020, 11, 1082–1091, doi:10.3762/bjnano.11.93

• the stacking of particles in the form of plates (Figure 4a,b). The ZnAl-NAA-LDH sample exhibits a surface in the form of compact plates (Figure 4c,d). In vitro experiments to prove the efficiency of ZnAl-NAA-LDH as a slow-release matrix were performed in solutions with pH 4 and pH 7, and the release

Monolayers of MoS₂ on Ag(111) as decoupling layers for organic molecules: resolution of electronic and vibronic states of TCNQ

• Asieh Yousofnejad,
• Gaël Reecht,
• Nils Krane,
• Christian Lotze and
• Katharina J. Franke

Beilstein J. Nanotechnol. 2020, 11, 1062–1071, doi:10.3762/bjnano.11.91

• direct comparison with the dI/dV maps, we calculate the tunneling matrix element between an s-wave tip and the spatially resolved molecular wave function across the molecule [51]. The maps of the square of the tunneling matrix element are depicted in Figure 5e next to the corresponding molecular orbitals

• . Because LUMO+1 and LUMO+2 are quasi-degenerate, we used the sum of their wave functions for the calculations of the tunneling matrix elements. As expected, the nodal planes of the molecular orbitals dominate the simulated dI/dV maps and can be taken as a robust signature for molecular orbital

• LUMO with the double U-shape being in very good agreement with the calculations of the tunneling matrix element. The very same signatures in the conductance map at 0.64 V suggest that this resonance stems from the LUMO as well. The DFT calculations show that the LUMO is non-degenerate. Hence, we can

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

• susceptibility tensor is calculated using the Kubo–Greenwood formula [25][26]: where is the i-th component of the dipole matrix element between states n and m, Γ is the broadening, and f is the Fermi function. The constants e, ℏ, m, ε0 and V are the electron charge, Planck’s constant, electron mass, vacuum

• -energies are [28][29]: where E± = E ± ℏω. M is the first-order coupling matrix and N is the number of photons per unit of time per unit area. Thus, the Green’s functions involving the first-order electron–photon interaction are given as [28][29]: In Equations 4–7, , and represent the non-interacting

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

• nanoparticles agglomerated into clusters inside the fiber matrix. The helical constructs exhibited a diameter of approximately 500 µm with one to two windings per millimeter. Due to their ferromagnetic properties they are easily attracted to a permanent magnet. The results from the tensile testing show that the

• polysaccharides such as alginate, hyaluronic acid or chitosan, are widely used as biocompatible materials since they are biochemically similar to the native extracellular matrix (ECM) [16]. Chitosan is a biopolymer that combines excellent biocompatibility, low toxicity and antibacterial properties with a low

• ]. Additionally, by using either wet-spinning or electrospinning techniques, nanoparticles can be suspended into the viscous spinning solution and embedded into the fiber matrix. For example, silver nanoparticles have been incorporated into electrospun chitosan fibers enabling antibacterial activity in wound

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

• used to simulate a single experimental dataset. The top-level function is passed to lsqcurvefit(), which will call all of the sub-functions while fitting the parameters. The MATLAB function lsqcurvefit() is also capable of taking an input matrix as opposed to simply an array of data, meaning it could

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

• , are introduced by the vector This vector, the so-called transition noise vector, is anticipated to be Gaussian white noise (0,QK) with the covariance matrix The output of the Kelvin system is the scalar value of the intrinsic frequency shift . It is defined by using the definition in Equation 10. The

• spectral density (PSD) of the thermal noise can be calculated as For detection-noise-limited measurements, an additional state has to be introduced to keep track of the dynamics of the apparent noise. The approximation in Equation 17 contains the system output matrix . It depends on the current tip–sample

• voltage Uts,k and linearizes the system around the state . It is defined by The intrinsic frequency shift, , then enters the detection system, which is modeled by the linear time-invariant system represented by the state transition matrix FD, input matrix GD, output matrix HD, and feed-through coefficient

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

• morphology, or in the formation of ZnO particles embedded into the ZnMgO matrix, respectively. Local compositional fluctuations leading to the formation of deep band tails in the gap were deduced from photoluminescence spectra. A model for the band tail distribution in the bandgap is proposed as a function

• embedded into the ZnMgO alloy matrix, which is responsible for the high energy broad PL band. To demonstrate that the low energy PL band is related to ZnO crystallites, it is compared to the spectrum of a high quality ZnO crystal measured at low temperature (curve 4 in Figure 5b). One can see that the

• nanoparticles embedded into the ZnMgO matrix are useful for fast electron transport and high charge balance in quantum dot light emitting diodes [22]. The multiphase composition of films prepared by spin coating and annealed at temperatures lower that 450 °C was revealed by X-ray diffraction (XRD) analysis. As

Key for crossing the BBB with nanoparticles: the rational design

• Sonia M. Lombardo,
• Marc Schneider,
• Akif E. Türeli and
• Nazende Günday Türeli

Beilstein J. Nanotechnol. 2020, 11, 866–883, doi:10.3762/bjnano.11.72

• nanoparticles to cross the BBB, as it has been shown in multiple studies [87][123][145][146]. However, coating nanoparticles with PEG allows them to better diffuse through the ECS [147]. Indeed, an important constituent of the ECS is the extracellular matrix, constituted of proteoglycans, hyaluronan and small

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

• energy in each group (±20 meV) was attributed to variations of the strain in the h-BN matrix, as well as photo-conversion to a dark state that may be responsible for the blinking. Only 5% of the emitters were photostable. The photo-dynamics indicates the presence of a metastable state (3-level system

Effect of Ag loading position on the photocatalytic performance of TiO₂ nanocolumn arrays

• Jinghan Xu,
• Yanqi Liu and
• Yan Zhao

Beilstein J. Nanotechnol. 2020, 11, 717–728, doi:10.3762/bjnano.11.59

• ], localized surface plasmon resonance (LSPR) [25], and plasma excitation light scattering [26][27]. Cushing et al. [28] used the time-resolved method to track these three processes by establishing a density matrix model, which allowed them to predict the theoretical maximum catalytic efficiency and

Stochastic excitation for high-resolution atomic force acoustic microscopy imaging: a system theory approach

• Edgar Cruz Valeriano,
• José Juan Gervacio Arciniega,
• Christian Iván Enriquez Flores,
• Susana Meraz Dávila,
• Joel Moreno Palmerin,
• Martín Adelaido Hernández Landaverde,
• Yuri Lizbeth Chipatecua Godoy,
• Aime Margarita Gutiérrez Peralta,
• Rafael Ramírez Bon and
• José Martín Yañez Limón

Beilstein J. Nanotechnol. 2020, 11, 703–716, doi:10.3762/bjnano.11.58

• and Equation 9 have to be considered in a mathematical process as follows: (1) Each numerator and each denominator, either of Equation 8 or of Equation 9, have to be changed to a matrix form. (2) Once each numerator is in a matrix form, the PSD formula is applied to this matrix form. (3) Once each

• denominator is in a matrix form, the PSD formula is applied to this matrix form. (4) The PSD for each numerator and denominator are put together in one equation, which is the same transfer function described in either Equation 8 or Equation 9, but in the frequency domain as a result of the stochastic

• numerator and denominator. The PSD for a denominator term is calculated taking into account the n-th denominator from Equation 12 as which can be transformed into the matrix form [21][29] as where x1 is the deflection of the cantilever, y1 is the deflection of the cantilever, and u is the force described

Effect of substitutional defects on resonant tunneling diodes based on armchair graphene and boron nitride nanoribbons lateral heterojunctions

• Majid Sanaeepur

Beilstein J. Nanotechnol. 2020, 11, 688–694, doi:10.3762/bjnano.11.56

• Table 1 [37]. In nonequilibrium Green’s functions the retarded Green’s function of the device (scattering region) is written as [38]: where η is an infinitesimal positive number and the non-Hermitian self-energy matrix, Σ(E) = Σ1(E) + Σ2(E), represents the escape rate of electrons from the device into

A novel dry-blending method to reduce the coefficient of thermal expansion of polymer templates for OTFT electrodes

• Xiangdong Ye,
• Bo Tian,
• Yuxuan Guo,
• Fan Fan and
• Anjiang Cai

Beilstein J. Nanotechnol. 2020, 11, 671–677, doi:10.3762/bjnano.11.53

• in a polymer to obtain a composite. Shokrieh et al. [10] carried out a systematic theoretical study to investigate the influence of carbon nanotubes (CNTs) on the CTE of CNT/epoxy, and the results indicate that the addition of 1 wt % CNT causes a significant decrease of the CTE of the matrix

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

Silver-decorated gel-shell nanobeads: physicochemical characterization and evaluation of antibacterial properties

• Marta Bartel,
• Katarzyna Markowska,
• Marcin Strawski,
• Krystyna Wolska and
• Maciej Mazur

Beilstein J. Nanotechnol. 2020, 11, 620–630, doi:10.3762/bjnano.11.49

• -resolution spectra for these elements. The direct evidence for metallic silver embedded in the polymer matrix is the spin–orbit doublet recorded at 368.3 and 374.3 eV for Ag 3d5/2 and 3d3/2, respectively (Figure 5A), followed by plasmon loss peaks at 372 and 378 eV [30][31]. However, the asymmetric shape of

• reports indicating a profound resistance of bacteria grown in biofilms to antimicrobials. Bacterial biofilms are generally less susceptible to silver nanoparticles than planktonic cells, probably due to the extracellular matrix coating the cells in a biofilm, aggregation of the cells to reduce their