Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

• Varsha Sharma and
• Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

• charging of wall components and affect the wall structure, thereby affecting the capsule wall integrity. In spite of the versatility, in addition to the inexpensive and easy fabrication of electrostatic assemblies, the response over a wide pH range becomes a limitation as it is biologically irrelevant

High dynamic resistance elements based on a Josephson junction array

• Konstantin Yu. Arutyunov and
• Janne S. Lehtinen

Beilstein J. Nanotechnol. 2020, 11, 417–420, doi:10.3762/bjnano.11.32

• connected in series, each being a Al–AlOx–Al junction with a gap of about 400 µV. The charging energy, Ec = e2/2C, of each SIS contact (considering it to be a plate capacitor with dielectric constant ε ≈ 10, area 100 × 100 nm and distance between plates ≈2 nm) is about two orders of magnitude higher than

• the Josephson energy, EJ = Ic/2e. As EJ << Ec the physics of the system is dominated solely by charging phenomena. At zero magnetic field and small current bias, the dynamic resistance Rdyn ≡ dV/dI of the JJ chain can reach ≈1011 Ω (Figure 2b), while at a higher bias, Rdyn (I >> 0) approaches 100 kΩ

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

• the development of new time-resolved extensions of electrostatic force microscopy (EFM) and Kelvin probe force microscopy (KPFM). Time-resolved EFM (trEFM) has been used to map photoinduced charging rates (i.e., the time needed to reach an electrostatic equilibrium after illumination) in organic donor

Nanosecond resistive switching in Ag/AgI/PtIr nanojunctions

• Botond Sánta,
• Dániel Molnár,
• Patrick Haiber,
• Agnes Gubicza,
• Edit Szilágyi,
• Zsolt Zolnai,
• András Halbritter and
• Miklós Csontos

Beilstein J. Nanotechnol. 2020, 11, 92–100, doi:10.3762/bjnano.11.9

• implemented on identical, impedance-matched printed co-planar waveguide circuit boards, is shown in Figure 4b. The operation of G1 and G2 relies on the recurring charging and avalanche break-down of the 2N2369-type npn transistor. Charging occurs through the 1 MΩ resistor and the 2 pF capacitor located at the

Synthesis of amorphous and graphitized porous nitrogen-doped carbon spheres as oxygen reduction reaction catalysts

• Maximilian Wassner,
• Markus Eckardt,
• Andreas Reyer,
• Thomas Diemant,
• Michael S. Elsaesser,
• R. Jürgen Behm and
• Nicola Hüsing

Beilstein J. Nanotechnol. 2020, 11, 1–15, doi:10.3762/bjnano.11.1

• support to the C 1s signal of the carbon-containing catalyst film. The spectra showed minor charging effects, which were compensated by a neutralizer (low-energy electron flood gun). The C 1s peak was set to 284.8 eV for binding energy calibration [50]. Evaluation and deconvolution of the measured signals

• electrolyte were subtracted from the measured ORR currents in order to remove double-layer charging currents. For each catalyst the cyclic voltammograms are presented, thus the ORR measurements of each catalyst consist of a cathodic (down-going scan, lower trace) and an anodic (up-going scan, upper trace

Adsorption and desorption of self-assembled L-cysteine monolayers on nanoporous gold monitored by in situ resistometry

• Elisabeth Hengge,
• Eva-Maria Steyskal,
• Rupert Bachler,
• Alexander Dennig,
• Bernd Nidetzky and
• Roland Würschum

Beilstein J. Nanotechnol. 2019, 10, 2275–2279, doi:10.3762/bjnano.10.219

• demonstrates good reproducibility of the desorption peak at −820 mV. During desorption, the resistance (Figure 3b) strongly decreases by about 7.2%. In subsequent cycles it varies in a range of 4%, matching our earlier results for double-layer charging of npAu [19]. A slight drift during repeated cycling is

• most likely caused by sample degradation. The charge transfer of 0.15 C during desorption is a superposition of actual cysteine desorption and double-layer charging (with an increasing contribution as cysteine is desorbed). When we assume the double-layer capacitance to increase roughly proportionally

• to the total charge transfer, this yields contributions of 0.06 C for the double layer and 0.09 C for the cysteine desorption. This charge transfer can be associated with a resistance variation of 2.4% (estimated from the variations upon double-layer charging in following cycles) and 4.8

A novel all-fiber-based LiFePO₄/Li₄Ti₅O₁₂ battery with self-standing nanofiber membrane electrodes

• Li-li Chen,
• Hua Yang,
• Mao-xiang Jing,
• Chong Han,
• Fei Chen,
• Xin-yu Hu,
• Wei-yong Yuan,
• Shan-shan Yao and
• Xiang-qian Shen

Beilstein J. Nanotechnol. 2019, 10, 2229–2237, doi:10.3762/bjnano.10.215

• active substances and electrolyte. The resistance of Li+ during charging and discharging of the battery decreases, and the internal structure of the material cannot collapse of deform easily. Thus, the structure of the material remains unchanged even after many cycles [40][41]. TEM images of the LiFePO4

• , which are consistent with the CV curves, corresponding to the processes of Li+ removal from and intercalation in LiFePO4 and Li4Ti5O12, respectively. It is noteworthy that two smaller plateaus for charging and discharging of TiO2 are also found on the charge-discharge curves of Li4Ti5O12, which is in

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

• curves of the ASC at different potential windows with a scan rate of 10 mV·s−1; (c) CV curves of the device at various sweep rates and (d) GCD curves of ASC at different charging/discharge current densities; and (e) the corresponding specific capacitance, (f) cycling stability of the ASC under a current

Oblique angle deposition of nickel thin films by high-power impulse magnetron sputtering

• Hamidreza Hajihoseini,
• Movaffaq Kateb,
• Snorri Þorgeir Ingvarsson and
• Jon Tomas Gudmundsson

Beilstein J. Nanotechnol. 2019, 10, 1914–1921, doi:10.3762/bjnano.10.186

• was 25 cm. We used thermally oxidized Si(001) with an oxide thickness of 100 nm as substrates. However, for the scanning electron microscopy studies, Si(001) substrates with native oxide were used in order to eliminate the charging effect. All films were deposited at room temperature (25 °C) with a

Tuning the performance of vanadium redox flow batteries by modifying the structural defects of the carbon felt electrode

• Ditty Dixon,
• Deepu Joseph Babu,
• Aiswarya Bhaskar,
• Hans-Michael Bruns,
• Joerg J. Schneider,
• Frieder Scheiba and
• Helmut Ehrenberg

Beilstein J. Nanotechnol. 2019, 10, 1698–1706, doi:10.3762/bjnano.10.165

• the charging current reached less than 10 mA cm−2. All the cyclic voltammetry measurements were carried out at a scan rate of 5 mV s−1. Single-cell measurements were performed using a modified direct methanol fuel cell from ElectroChem, having a pin-type flow field with an active area of 25 cm2

• 1.8 V and 0.7 V were used for the charging and discharging steps, respectively. Between the charging and discharging, the cell was kept at an open-circuit voltage condition for 5 min. Long-term cycling measurements were carried out at a current density of 80 mA cm−2 with fresh electrolyte and fresh

Stationary beam full-field transmission helium ion microscopy using sub-50 keV He⁺: Projected images and intensity patterns

• Michael Mousley,
• Santhana Eswara,
• Olivier De Castro,
• Olivier Bouton,
• Nico Klingner,
• Christoph T. Koch,
• Gregor Hlawacek and
• Tom Wirtz

Beilstein J. Nanotechnol. 2019, 10, 1648–1657, doi:10.3762/bjnano.10.160

• revealed that these samples charge significantly under He+ ion irradiation. The spot patterns obtained in the THIM experiments are explained as artefacts related to sample charging. The results presented here indicate that factors other than channeling, blocking and surface diffraction of ions have an

• impact on the final intensity distribution in the far field. Hence, the different processes contributing to the final intensities will need to be understood in order to decouple and study the relevant ion-beam scattering and deflection phenomena. Keywords: charging; helium ion microscopy; ion

• He+ ions. The observed differences in the He+ ion intensity distribution as well as unexpected spot patterns are discussed. The results suggest that information about the sample morphology can be extracted. The results also show that charging-related effects can significantly contribute to the final

Upcycling of polyurethane waste by mechanochemistry: synthesis of N-doped porous carbon materials for supercapacitor applications

• Christina Schneidermann,
• Pascal Otto,
• Desirée Leistenschneider,
• Sven Grätz,
• Claudia Eßbach and
• Lars Borchardt

Beilstein J. Nanotechnol. 2019, 10, 1618–1627, doi:10.3762/bjnano.10.157

• introduced between charging and discharging. The gravimetric capacitance was calculated from the discharge curve via the following equation: with specific capacitance Cspec, cell voltage U corrected by IR drop, and carbon mass of both electrodes m (without binder). Upcycling approach consisting of high

Kelvin probe force microscopy work function characterization of transition metal oxide crystals under ongoing reduction and oxidation

• Dominik Wrana,
• Karol Cieślik,
• Wojciech Belza,
• Christian Rodenbücher,
• Krzysztof Szot and
• Franciszek Krok

Beilstein J. Nanotechnol. 2019, 10, 1596–1607, doi:10.3762/bjnano.10.155

• reproducible Kelvin parabola with negative curvature for both structures. As up and down bias sweeps appear to follow the same curve, and there is no sign of charging or charge transfer. A comparative study of LC-AFM and KPFM of the TiO/SrTiO3 structure enables a clear distinction between two materials of

Rapid thermal annealing for high-quality ITO thin films deposited by radio-frequency magnetron sputtering

• Petronela Prepelita,
• Ionel Stavarache,
• Doina Craciun,
• Florin Garoi,
• Catalin Negrila,
• Beatrice Gabriela Sbarcea and
• Valentin Craciun

Beilstein J. Nanotechnol. 2019, 10, 1511–1522, doi:10.3762/bjnano.10.149

• sputtered onto the sample surfaces prior to imaging and cross-sectional analysis to avoid electrostatic charging during the measurements. The elemental and chemical composition of the ITO thin films as well as the electronic state of the elements within the material were investigated by X-ray photoelectron

• spectroscopy (XPS) method. A SPECS spectrometer with a PHOIBOS RX 150 analyzer and a Specs XR–50 M source was operated with a monochromatic Al anode (hν = 1486.61 eV) at 300 W. The charging effect of the sample deposited onto the quartz substrate is compensated for with a Specs FG15/40 flood gun. The chemical

Flexible freestanding MoS₂-based composite paper for energy conversion and storage

• Florian Zoller,
• Jan Luxa,
• Thomas Bein,
• Dina Fattakhova-Rohlfing,
• Daniel Bouša and
• Zdeněk Sofer

Beilstein J. Nanotechnol. 2019, 10, 1488–1496, doi:10.3762/bjnano.10.147

• paper for applications in supercapacitors (SCs). The capacitance was measured by a chronoamperometry technique in KCl solution (1 M) using different charging–discharging current densities (1–5 mA·cm−2) in a potential range determined by cyclic voltammetry (CV) shown in Supporting Information File 1

• electrode that comes into contact with the electrolyte solution S. The calculation was performed using equation: C = (2·I) / (S·U/t). The calculated values are summarized for each discharging current in Table 1. Charging–discharging curves of MoS2-based composite paper obtained using the chronoamperometry

• calomel reference electrode was used as the reference electrode and the measurements were performed in 1 M KCl solution. The exposed area was a disk with 0.94 mm diameter. In order to measure the charge–discharge curves, several charging–discharging currents (1–5 mA·cm−2) were used to charge the material

Hierarchically structured 3D carbon nanotube electrodes for electrocatalytic applications

• Pei Wang,
• Katarzyna Kulp and
• Michael Bron

Beilstein J. Nanotechnol. 2019, 10, 1475–1487, doi:10.3762/bjnano.10.146

• displayed in Figure 7. The currents in the CVs are associated with the charging and decharging of the electrical double layer and denote the double-layer capacity, which can be regarded as an estimation of the surface area for the carbon-only samples. In addition to these currents, in the potential range

• scan rate of 5 mV s−1 was applied. Note that the oxidation current scales with the square root of the scan rate, while the double-layer charging current linearly scales with scan rate. Thus, the slow scan rate allows for a much more reliable determination of peak potentials and currents. The fifth

Fabrication of phase masks from amorphous carbon thin films for electron-beam shaping

• Lukas Grünewald,
• Dagmar Gerthsen and
• Simon Hettler

Beilstein J. Nanotechnol. 2019, 10, 1290–1302, doi:10.3762/bjnano.10.128

• (transmission) electron microscopy (S(T)EM). Phase-modulating thin-film devices (phase masks) made of amorphous silicon nitride are commonly used to generate a wide range of different beam shapes. An additional conductive layer on such a device is required to avoid charging under electron-beam irradiation

• , which induces unwanted scattering events. Results: Phase masks of conductive amorphous carbon (aC) were successfully fabricated with optical lithography and focused ion beam milling. Analysis by TEM shows the successful generation of Bessel and vortex beams. No charging or degradation of the aC phase

• , smooth, free-standing SixNy thin films are commercially available. Smooth thin films are a requirement for the successful fabrication of the thickness pattern. However, SixNy is an insulator and an additional conductive layer has to be deposited onto a SixNy-based PM to avoid charging by electron-beam

Tailoring the stability/aggregation of one-dimensional TiO₂(B)/titanate nanowires using surfactants

• Atiđa Selmani,
• Johannes Lützenkirchen,
• Kristina Kučanda,
• Dario Dabić,
• Engelbert Redel,
• Ida Delač Marion,
• Damir Kralj,
• Darija Domazet Jurašin and
• Maja Dutour Sikirić

Beilstein J. Nanotechnol. 2019, 10, 1024–1037, doi:10.3762/bjnano.10.103

• /DTAB and TNW/12-2-12 systems was investigated in order to determine the effect of the surfactants on the surface charging in the respective dispersions. The measured variations of the zeta potential with pH are shown in Figure 6a,b. The two lowest monomer concentrations of both surfactants shifted the

• equilibria, a surface complexation model (SCM) was designed based on the one previously used to describe TNW charging in the absence of surfactants [48]. Not many surface complexation models involving surfactant adsorption are available. A recent example in the work of Tagavifar et al. involves a purely

• diffuse double layer model [57]. Here, we use a more complex model. The surface complexation model starts from the previous model developed for the bare TNWs. These fundamental charging settings are given in the first three lines of Table 2. Based on this, the zeta potential measurements in the presence

Concurrent nanoscale surface etching and SnO₂ loading of carbon fibers for vanadium ion redox enhancement

• Jun Maruyama,
• Shohei Maruyama,
• Tomoko Fukuhara,
• Toru Nagaoka and
• Kei Hanafusa

Beilstein J. Nanotechnol. 2019, 10, 985–992, doi:10.3762/bjnano.10.99

• voltammograms (CVs) obtained in an acidic electrolyte without vanadium ions are shown in Figure 4. The current in the voltammogram is composed from three components, i.e., the electrochemical double-layer charging current at the carbon–electrolyte interface, and the faradaic currents due to the redox reactions

• of the surface functional groups and the carbon surface oxidation. The electrochemical double-layer charging yields a constant current and a rectangular CV shape. The current depends on the extent of the exposure of the basal and edge planes, the specific capacitances of which are 16 and 50–70 μF·cm

• with high-purity water before the incorporation. The anolyte (40 cm3) and catholyte (20 cm3) were prepared by electrolysis (charging) of 1 M VOSO4 + 2 M H2SO4 until the full conversion of VO2+ to VO2+ and V2+. After the electrolysis, half of the anolyte was removed and the pre-discharge was carried out

Novel reversibly switchable wettability of superhydrophobic–superhydrophilic surfaces induced by charge injection and heating

• Xiangdong Ye,
• Junwen Hou and
• Dongbao Cai

Beilstein J. Nanotechnol. 2019, 10, 840–847, doi:10.3762/bjnano.10.84

• . Influence of temperature on coating wettability To evaluate the effect of heating temperature on the coating wettability, the temperature was changed gradually while the voltage was kept at 2000 V and the charging time was kept at 2 min, and the results are shown in Figure 9. At room temperature, the

• the following: the increase of temperature will promote the thermal motion of the molecules in the solid, which in turn will help the charges inject into the solid surface during the process of electric field application. Effect of charging time on durability of superhydrophilicity When the charging

• time is too short, the coating wettability cannot change from its original state (superhydrophobic) to superhydrophilic. For example, at 2000 V and 150 °C, the contact angle of the coating changed from 150.5° to 40° after 1 min. Only when the charging time is increased, such as at 2 min, will the

An efficient electrode material for high performance solid-state hybrid supercapacitors based on a Cu/CuO/porous carbon nanofiber/TiO₂ hybrid composite

• Mamta Sham Lal,
• Thirugnanam Lavanya and
• Sundara Ramaprabhu

Beilstein J. Nanotechnol. 2019, 10, 781–793, doi:10.3762/bjnano.10.78

• triangular shape during the charging and discharging steps, indicating complete electric double layer behavior. The Cu/CuO/PCNF/TiO2 composite shows the long charge/discharge duration which results from the typical pseudo-capacitive performance of the TiO2 nanoparticles in the composite. The specific

Trapping polysulfide on two-dimensional molybdenum disulfide for Li–S batteries through phase selection with optimized binding

• Sha Dong,
• Xiaoli Sun and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2019, 10, 774–780, doi:10.3762/bjnano.10.77

• ≤ 6), the final product of Li2S is formed upon discharging; and the charging process occurs through the reverse reactions [40]. The insulating nature of sulfur and the lithiation products (Li2S2 and Li2S), and the dissolution of higher-order Li2Sx (x = 4–8) are the main challenges in the application

On the transformation of “zincone”-like into porous ZnO thin films from sub-saturated plasma enhanced atomic layer deposition

• Alberto Perrotta,
• Julian Pilz,
• Stefan Pachmajer,
• Antonella Milella and
• Anna Maria Coclite

Beilstein J. Nanotechnol. 2019, 10, 746–759, doi:10.3762/bjnano.10.74

• charging was compensated using a dual beam charge neutralization, with a flux of low-energy electrons (ca. 1 eV) combined with positive Ar ions of very low energy (10 eV). Samples were sputter cleaned for 1 min with an Ar ion beam of 1 kV, 1 µA (raster size: 2 × 2 cm2). The acquired spectra were processed

• with CasaXPS software. The lattice O–Zn component of the O 1s spectrum was used as internal standard for charging correction and it was set to 529.8 eV [56]. Results and Discussion Optochemical characterization of the zincone-like layers Zincone-like layers were deposited by varying the plasma pulse

Review of time-resolved non-contact electrostatic force microscopy techniques with applications to ionic transport measurements

• Aaron Mascaro,
• Yoichi Miyahara,
• Tyler Enright,
• Omur E. Dagdeviren and
• Peter Grütter

Beilstein J. Nanotechnol. 2019, 10, 617–633, doi:10.3762/bjnano.10.62

• difference (which can be used to extract the local work function) [1] and local piezoelectric response [2], and dynamic properties such as the charging and decay times of photoexcited carriers [3][4][5][6], and local activation energies for ionic transport [7][8]. These measurements play a crucial role in

• build-up in the sample at the location of the AFM tip if an appropriate voltage is applied across the tip–sample gap. Measuring the resonance frequency shift as a function of time after the light is turned on/off then allows for the charging/discharging time to be directly acquired, revealing

• information about charge generation and transport in the sample. This was first performed by Krauss et al. who observed charging of photoexcited CdSe nanocrystals by direct frequency shift measurements after illumination [26]. The concept outlined above can be applied to measure ionic transport in ionic

Coexisting spin and Rabi oscillations at intermediate time regimes in electron transport through a photon cavity

• Vidar Gudmundsson,
• Hallmann Gestsson,
• Nzar Rauf Abdullah,
• Chi-Shung Tang,
• Andrei Manolescu and
• Valeriu Moldoveanu

Beilstein J. Nanotechnol. 2019, 10, 606–616, doi:10.3762/bjnano.10.61

• state. We notice that the mean photon number in the system only assumes a considerable value during the late charging regime from 100 ps to 0.6 μs, when radiative transitions assist in moving charge from the states in the bias window to the ground state of the system [9]. The steady-state photon number