Extended iron phthalocyanine islands self-assembled on a Ge(001):H surface

• Rafal Zuzak,
• Marek Szymonski and
• Szymon Godlewski

Beilstein J. Nanotechnol. 2021, 12, 232–241, doi:10.3762/bjnano.12.19

• holds also for layered materials. Single-molecule prototypes or molecular nanostructures are often prepared on metals, which usually provide a sufficiently low diffusion barrier for efficient self-assembly and simultaneously allow for in-depth analysis through atomically precise tools from the family of

A review on the green and sustainable synthesis of silver nanoparticles and one-dimensional silver nanostructures

• Sina Kaabipour and
• Shohreh Hemmati

Beilstein J. Nanotechnol. 2021, 12, 102–136, doi:10.3762/bjnano.12.9

• biosynthesis occurs outside of cells due to the presence of biomolecules [191], which depends on the type of cell culture used. For instance, cell-wall deficient cells are typically more inclined towards intracellular biosynthesis as the cell-wall is known to act as a barrier for the diffusion of metal cations

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

• . In [27], we suggested and verified the assumption that a lower density of a nanoscale compact material, in comparison with ordinary bulk samples, leads to an increase in the probability of formation of an atomic structure with a five-particle symmetry due to the greater diffusion mobility of the

Effect of different silica coatings on the toxicity of upconversion nanoparticles on RAW 264.7 macrophage cells

• Cynthia Kembuan,
• Helena Oliveira and
• Christina Graf

Beilstein J. Nanotechnol. 2021, 12, 35–48, doi:10.3762/bjnano.12.3

• and 21 ± 2 nm for the thick-shelled silica layer (samples UC@thin, Figure 1B, and UC@thick, Figure 1C, respectively). A thicker silica shell protects the UCNP core more efficiently than a thinner silica shell by reducing the diffusion of water molecules to the UCNPs and also by reducing a possible

• would have been much larger if only the reduction of the diffusion rate through the three times thicker shell had delayed the dissolution of the UCNPs [60]. The percentage values for Y3+ release are generally higher than that for Yb3+. This can be partially explained by the lower content of Yb3+ and the

Electron beam-induced deposition of platinum from Pt(CO)₂Cl₂ and Pt(CO)₂Br₂

• Aya Mahgoub,
• Hang Lu,
• Rachel M. Thorman,
• Konstantin Preradovic,
• Titel Jurca,
• Lisa McElwee-White,
• Howard Fairbrother and
• Cornelis W. Hagen

Beilstein J. Nanotechnol. 2020, 11, 1789–1800, doi:10.3762/bjnano.11.161

• ][29]. The larger height of the MeCpPtMe3 pillars compared to the Pt(CO)2Cl2 pillars is presumably caused by the higher partial pressure of MeCpPtMe3, but may also be caused by many other factors governing FEBID such as the surface residence time, the dissociation cross section, and surface diffusion

• File 1, Figure S4 shows the base diameters of the pillars grown from Pt(CO)2Cl2 and MeCpPtMe3. The diameters of pillars grown from both precursors are largest at 12 pA, presumably due to a larger contribution of precursor surface diffusion to the growth [29]. At low currents, the pillars grow more

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

• is a high risk of mutual diffusion and the formation of a thick “dead” layer, which also suppresses the transparency of the S/F interface [20]. In the case of materials wetting and limited mutual solubility (as in niobium–nickel and niobium–cobalt, with solubility of about 5% at room temperature

• multilayer nanosystem composition and structure due to the increase in the thermal diffusion processes. Conclusion The paper proposes a technique and describes a mathematical model for studying technological modes and parameters in the manufacture of multilayer nanosystems. The model was tested in the study

Mapping of integrated PIN diodes with a 3D architecture by scanning microwave impedance microscopy and dynamic spectroscopy

• Rosine Coq Germanicus,
• Peter De Wolf,
• Florent Lallemand,
• Catherine Bunel,
• Serge Bardy,
• Hugues Murray and
• Ulrike Lüders

Beilstein J. Nanotechnol. 2020, 11, 1764–1775, doi:10.3762/bjnano.11.159

• . The starting material is a p-type Si substrate with relatively high ohmic resistance (1 kΩ·cm), oriented along the ⟨100⟩ direction. The first step in the process consists of forming an n-type doped buried layer (BN) on the top of the wafer (through implantation and diffusion of the doping species). A

• diffusion of electron-acceptor species. Therefore, the intrinsic layer, acting as an insulator due to its low doping concentration, is stacked in between the p-type and n-type layers. The studied sample came from a fully processed wafer, designed for power electronic applications, in which both FEOL and

• ) highlights the type of doping in different Si layers, such as the BN implanted layer and the diffused doping along the deep trenches. In addition, the ∂C/∂V amplitude mapping (Figure 7b) identifies the implanted p+ anode area and reveals the diffusion shape of the BN implanted layer. sMIM-R and sMIM-C

PEG/PEI-functionalized single-walled carbon nanotubes as delivery carriers for doxorubicin: synthesis, characterization, and in vitro evaluation

• Shuoye Yang,
• Zhenwei Wang,
• Yahong Ping,
• Yuying Miao,
• Yongmei Xiao,
• Lingbo Qu,
• Lu Zhang,
• Yuansen Hu and
• Jinshui Wang

Beilstein J. Nanotechnol. 2020, 11, 1728–1741, doi:10.3762/bjnano.11.155

• molecules enter cells only by mobility or diffusion, while the individually dispersed nanotubes are more easily internalized by cells via direct penetration and endocytosis [38][43]. This can explain the above results. The fluorescence intensity of CNTs-PEG/DOX and CNTs-PEG-PEI/DOX increases further (Figure

• more efficient cell internalization and accumulation. The subsequent drug release and diffusion within the cytoplasm can induce apoptosis. The results suggest that CNTs-PEG-PEI may be developed to be a novel nanoscale delivery system of chemotherapeutic drugs for cancer therapy. Schematic

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

• metal-assisted etching technique. After fabrication, a thermal diffusion process is used for doping the nanowire forest with phosphorous. A suitable experimental technique has been developed for the measurement of the Seebeck coefficient under static conditions, and results are reported for different

• not possible to fabricate an optimized generator module based on two legs with opposite heavy doping. A possible solution is to dope the silicon nanowires by thermal diffusion [21], after their fabrication by MACE. In this work, we present the measurement of the Seebeck coefficient of SiNWs doped

• through a diffusion process, based on a solid source (see Methods section). The main point is that the diffusion process must be performed in a single step (predeposition step), because a drive-in step, typical of the standard diffusion processes currently applied in the semiconductor industry, would

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

• strongly enhanced at specific adsorption sites, which we refer to as “hot spots”. On Cu(111), the molecules can reach these hot spots only by temperature-induced diffusion. Whereas, after deposition at 20 K, the molecules stay statistically distributed on the surface, and only a small fraction is located

• at these sites where the SERS effect occurs. On hBN/Cu(111), the significantly smaller interaction between PTCDA and the hBN surface compared to Cu(111) and a consequently smaller corrugation of the bonding potential lead to a much higher mobility, which allows for a diffusion to the hot spots even

• , while at lower coverages its formation requires annealing. Hence, we assign FLA to PTCDA molecules at surface defects. In a sub-monolayer, the molecules can reach these defects via diffusion, which has to be temperature-induced. For a higher coverage, the sites at defects are already populated during

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

• carrier diffusion, and a corresponding intrinsic electric field (Eb) is formed in the depletion zone (Figure 2, left). Under this circumstance, the electron diffusion current and drift current are equal in magnitude and opposite in direction in the heterojunction. Therefore, the net current flowing

Oxidation of Au/Ag films by oxygen plasma: phase separation and generation of nanoporosity

• Abdel-Aziz El Mel,
• Said A. Mansour,
• Mujaheed Pasha,
• Atef Zekri,
• Janarthanan Ponraj,
• Akshath Shetty and
• Yousef Haik

Beilstein J. Nanotechnol. 2020, 11, 1608–1614, doi:10.3762/bjnano.11.143

• silver and gold. In addition, it was shown that the preferential oxidation of silver resulted in a solid-state diffusion of silver toward the surface where it oxidized and formed nanoporous microspheres. The gold phase remaining in the film exhibited nanoporosity due to the injected vacancies at the

• metal/silver oxide interface. Based on the scanning transmission electron microscopy analysis coupled with energy dispersive X-ray mapping a mechanism was proposed based on solid-state diffusion and the Kirkendall effect to explain the different steps occurring during the oxidation process. Keywords

• min, the nanoporous microspheres started to form, as previously discussed, and a 30% decrease in film thickness was also observed (Figure 3c,d). The decrease in film thickness resulted from the phase separation event and the diffusion of silver toward the surface, which was also responsible for the

High-responsivity hybrid α-Ag₂S/Si photodetector prepared by pulsed laser ablation in liquid

• Raid A. Ismail,
• Hanan A. Rawdhan and
• Duha S. Ahmed

Beilstein J. Nanotechnol. 2020, 11, 1596–1607, doi:10.3762/bjnano.11.142

• without and with CTAB under forward and reverse current flow. The forward current flow increased exponentially with bias voltage for the Ag2S/Si heterojunction synthesized in the presence of the CTAB surfactant, indicating the dominance of diffusion current. In the case of the heterojunction prepared

• to be 1.5 × 102% and 4.5 × 103% at 510 nm, respectively. This significant increase in the responsivity and quantum efficiency of the photodetector after CTAB addition can be ascribed to the widened depletion layer width and increased minority carrier diffusion length as well as to the large surface

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

• rotation of structures Hy2 and Hy3, and free diffusion of structures Ox3, Ox5, and Hy1–Hy3, even at low temperatures. Electronic structure We analyzed the charge distribution of the stable adsorbates with the Mulliken analysis of partial charges and investigated their partial DOS to study the effect of

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

• further search for the lowest-energy configuration was carried out. Results Figure 3 demonstrates the different situations encountered after depositing 1 or 2 on the ultra-thin 1BL CoO film. To activate surface diffusion of the molecules, a temperature of 300–320 K was applied to both systems either by

• molecular state at temperatures of 80 K and above prevents the molecules from locking into a compact self-assembled layer at low coverage. When stationary molecules with a rotational potential barrier larger than the diffusion barrier self-assemble, the intermolecular forces guide the molecules to diffuse

• into a state of low-energy at an appropriate bonding distance. This is, for example, observed at low coverage of 2H-DPP on Cu(111) [23]. When, as it appears here, the diffusion and the rotational barrier are of equal magnitude, the intermolecular forces cannot exert their directional influence on the

Antimicrobial metal-based nanoparticles: a review on their synthesis, types and antimicrobial action

• Matías Guerrero Correa,
• Fernanda B. Martínez,
• Cristian Patiño Vidal,
• Camilo Streitt,
• Juan Escrig and
• Carol Lopez de Dicastillo

Beilstein J. Nanotechnol. 2020, 11, 1450–1469, doi:10.3762/bjnano.11.129

• ]. Chen et al. (2019) also developed an antimicrobial-based biocomposite containing Ag NPs with good antibacterial properties against E. coli and S. aureus, as shown by the disk diffusion method [102]. Copper nanoparticles are nanomaterials with good chemical stability, heat resistance, and excellent

• vitro antimicrobial activity The in vitro antimicrobial activity of metal-based NPs can be evaluated through several clinical microbiological methods, where the disk diffusion and the broth or agar dilution methods are the main techniques used. The agar disk diffusion method is routinely used to analyze

• . As a result, approximate MIC values can be obtained; however, this method cannot distinguish between bactericidal or bacteriostatic effects [146]. The agar diffusion method can also be modified depending on the research study. For example, in order to study the antibacterial activity of Ag NPs

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

• material. Thus, the interaction between the catalytic nanodroplets and the substrate surface must be investigated in more detail to provide a better understanding and control over the process. In the present work, the surface diffusion processes were examined in order to understand and effectively control

• a change in the surface recombination of gold on silicon formed during cooling [29]. The diffusion activation energy of the Ostwald ripening process, EA, can be calculated using the qualitative correlation where T is the temperature, dd is the mean droplet diameter, and kB is the Boltzmann constant

• . For the data shown in Figure 2b, the value obtained for of EA is 1.79 eV, which is in agreement with the values in the literature (1.56 eV). For gold on silicon oxide, the activation energy for surface diffusion cannot be calculated since the temperatures considered here are too low to cause a

Controlling the proximity effect in a Co/Nb multilayer: the properties of electronic transport

• Sergey Bakurskiy,
• Mikhail Kupriyanov,
• Nikolay V. Klenov,
• Igor Soloviev,
• Andrey Schegolev,
• Roman Morari,
• Yury Khaydukov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1336–1345, doi:10.3762/bjnano.11.118

• depends on the relative resistivity values and coherence lengths of a chosen material. When the ferromagnetic metal and the superconductor have the same resistivity and diffusion coefficients (i.e., for γ = 1), the pair potential in the whole structure grows evenly with the temperature decrease (Figure 2a

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

• ] studied the impact of Brownian motion and thermophoresis diffusion on Casson nanofluid boundary layer flow over a nonlinear inclined stretching sheet. An unsteady flow of a Casson fluid along a nonlinear stretching surface was studied by Ullah et al. [30]. A Casson fluid over a non-isothermal cylinder

• viscosity, ρf is the fluid density, α represents the thermal diffusivity, Cp represents a constant pressure for a specific heat value, k0 denotes a chemical reaction coefficient, (ρcp)f represents the heat capacity, DB represents the Brownian diffusion coefficient, Q0 represents the volumetric heat

• 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

Growth of a self-assembled monolayer decoupled from the substrate: nucleation on-command using buffer layers

• Robby Reynaerts,
• Kunal S. Mali and
• Steven De Feyter

Beilstein J. Nanotechnol. 2020, 11, 1291–1302, doi:10.3762/bjnano.11.113

• symmetry of the underlying alkane layer [27]. Buffer layers of tetratriacontane [25] and tridecylamine [31] were used to template the self-assembly of copper phthalocyanine. Room temperature STM measurements revealed that the adsorption as well as the diffusion of clusters of CuPc molecules was strongly

• diffusion on buffer layers compared to that on pristine unmodified solid substrates. The result could be a selection of a polymorph that is otherwise not obtained under ‘normal’ experimental conditions. The decoupling effects could be significant especially for organic building blocks substituted with long

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

• after carbonization due to the combined effect of thermal drafting and chemical reaction. Given that there is an uneven heat transfer and diffusion during the carbonization process, the chemical structure of the CNFs is distributed along a radial gradient, resulting in a thermal drafting effect. As the

• . This is due to the fact that large mesoporous holes are more suitable for rapid ion diffusion at a high-load current density. This way, the specific surface area generated by these pores is effectively utilized [39]. At relatively high pressure values (P/P0 > 0.5), there was an evident hysteresis loop

• higher mesopore volume fraction (Figure 4 and Table 1). The mesoporous structures provided a shorter path and a lower resistance for ion diffusion in porous electrodes by increasing the electrode specific surface area. Therefore, mesoporous structures are more suitable for high-speed ion diffusion under

Proximity effect in [Nb(1.5 nm)/Fe(x)]₁₀/Nb(50 nm) superconductor/ferromagnet heterostructures

• Yury Khaydukov,
• Sabine Pütter,
• Laura Guasco,
• Roman Morari,
• Gideok Kim,
• Thomas Keller,
• Anatolie Sidorenko and
• Bernhard Keimer

Beilstein J. Nanotechnol. 2020, 11, 1254–1263, doi:10.3762/bjnano.11.109

• , differ by a factor of two, which makes neutron reflectometry a better choice to study diffusion in periodic Fe/Nb structures. Another advantage of neutron reflectometry is its sensitivity to the magnetic depth profile. The total SLD for spin-up(+) and spin-down(−) neutrons can be written as ρ±(z) = ρ0(z

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

• nanoparticle Néel relaxation time in oblique magnetic fields is given by [21][22] where ΔEi12 and ΔEi21 are the normalized energy barriers for the magnetic moment reorientations. The magnetisation-free diffusion time (τi0N) for low damping is [21][22] where vi is the volume of the i-th nanoparticle, Ms is the

3D superconducting hollow nanowires with tailored diameters grown by focused He⁺ beam direct writing

• Rosa Córdoba,
• Alfonso Ibarra,
• Dominique Mailly,
• Isabel Guillamón,
• Hermann Suderow and
• José María De Teresa

Beilstein J. Nanotechnol. 2020, 11, 1198–1206, doi:10.3762/bjnano.11.104

• volume rapidly decreases as a function of the ion beam current for the same dose (Figure 2). When using high currents several effects can play a role in this dependence such as precursor depletion, local heating, which decreases the precursor molecule sticking coefficient, and low precursor diffusion

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

• mobility. This additional diffusion barrier thus hampers the molecular self-assembly and can be overcome by a higher substrate temperature during the film growth, which agrees with our structural findings above. Conclusion To summarize, we investigated the influence of an h-BN interlayer on the optical