Selective porous gates made from colloidal silica nanoparticles

• Roberto Nisticò,
• Paola Avetta,
• Paola Calza,
• Debora Fabbri,
• Giuliana Magnacca and
• Dominique Scalarone

Beilstein J. Nanotechnol. 2015, 6, 2105–2112, doi:10.3762/bjnano.6.215

• materials (see inset in Figure 3A). The N2 gas-volumetric isotherm shown in Figure 3A is of the IV type, with a small hysteresis loop of H2 type (from IUPAC classification) in the relative pressure range 0.9–1, next to the condensation limit. The BET surface area is of ca. 260 m2 g−1 and the DFT pore size

Controlled switching of single-molecule junctions by mechanical motion of a phenyl ring

• Yuya Kitaguchi,
• Satoru Habuka,
• Hiroshi Okuyama,
• Shinichiro Hatta,
• Tetsuya Aruga,
• Thomas Frederiksen,
• Magnus Paulsson and
• Hiromu Ueba

Beilstein J. Nanotechnol. 2015, 6, 2088–2095, doi:10.3762/bjnano.6.213

• remarkable hysteresis appears when the molecule is successfully lifted and released. Note that Δz is defined as the distance toward the molecule with respect to the initial set point, as depicted in the inset. The current during the approach shows a jump at Δz = 2.6 Å to the high-current state, which returns

Nanostructured superhydrophobic films synthesized by electrodeposition of fluorinated polyindoles

• Gabriela Ramos Chagas,
• Thierry Darmanin and
• Frédéric Guittard

Beilstein J. Nanotechnol. 2015, 6, 2078–2087, doi:10.3762/bjnano.6.212

• properties, characterized by extremely high water contact angles (θw) and low water adhesion or hysteresis (also known as “Lotus effect”), grows exponentially because of the importance for both the scientific and industrial community [1][2][3][4][5][6]. Superhydrophobic properties are quite common in nature

• θwater for the C6F13-polyindoles can be seen in Figure 5. Indeed, not only θwater of 159.0° were measured on this polymer, but also highly oleophobic properties with θhexadecane = 93.3°. Moreover, the polymer presents extremely low hysteresis and sliding angles for normalized charges of 50 and 100 mC·cm

• Wenzel equation [36] (cos θ = r·cos θY, where r is a roughness parameter), the surface roughness can increase θ, but only if θY > 90°. Hence, it is possible to have an extremely high θwater, but the contact angle hysteresis (H) is usually high because the surface roughness increases also the solid–liquid

Two-phase equilibrium states in individual Cu–Ni nanoparticles: size, depletion and hysteresis effects

• Aram S. Shirinyan

Beilstein J. Nanotechnol. 2015, 6, 1811–1820, doi:10.3762/bjnano.6.185

• transformation of binary alloyed nanoparticles taking into account size effects as well as depletion and hysteresis effects. In such a way the hysteresis in a form of nonsymmetry for forth and back transforming paths takes place; compositional splitting and the loops-like splitted path on the size dependent

• the point for nanosolidus. Thus nanosolidus and nanoliquidus may be not interrelated. We call this difference between the end point of forth transition and starting point of back transition as ‘thermodynamic hysteresis’. Similar effect has been shown for a structural transition of Fe-nanoparticle

• ensemble subjected to temperature change [41]. The reason of such hysteresis is nonsymmetry of transforming path of a nanosystem with respect to the initial conditions leading to differences in two-phase loops of nanomelting and nanosolidification in presented case. For example, for Cu–Ni nanoparticle

A facile method for the preparation of bifunctional Mn:ZnS/ZnS/Fe₃O₄ magnetic and fluorescent nanocrystals

• Houcine Labiadh,
• Tahar Ben Chaabane,
• Romain Sibille,
• Lavinia Balan and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2015, 6, 1743–1751, doi:10.3762/bjnano.6.178

• could be related to the quantum confinement effects of nanocrystals and to the diamagnetic contribution of the ZnS core. At 2 K, all bifunctional nanoparticles exhibited hysteresis with remnance magnetization, MR, at 9 T and coercivity, HC, indicating a dominant ferromagnetic nature of the iron oxide

• layer. The magnetic characteristics (MR, M9T, and HC) of the samples are given in Table 2. One can observe that the hysteresis loops are not saturated even for fields up to ±9 T; this could be due to frozen spins at the surface of the nanocrystals as reported in previous works [32][33]. The coercive

• fields increased with the iron oxide layer thickness, where the highest HC value of 0.18 T was measured for Mn:ZnS/ZnS/Fe3O4 QDs (3). Thus, the nanocrystals become magnetically harder with an increasingly open hysteresis loop with increasing thickness of the magnetite shell. The values of MR and M9T

Radiation losses in the microwave K_u band in magneto-electric nanocomposites

• Talwinder Kaur,
• Sachin Kumar,
• Jyoti Sharma and
• A. K. Srivastava

Beilstein J. Nanotechnol. 2015, 6, 1700–1707, doi:10.3762/bjnano.6.173

• interaction between the spins of hexaferrite and polyaniline are effecting the motion of π electrons, which causes an increase the absorption curve area [5][35]. Magnetic properties Hysteresis loops for PANI/Barium ferrite composites recorded at room temperature are shown in Figure 4. The magnetic parameters

• hexaferrite and (b) composite COP at room temperature in the X band. Hysteresis loops of composites. Transmission electron micrographs of magneto-electric composites (a) cluster of composites (b and c) particles of hexaferrite enclosed by polyaniline (CL6P). Reflection loss for composites. Real (µ′) and

Synthesis, characterization and in vitro biocompatibility study of Au/TMC/Fe₃O₄ nanocomposites as a promising, nontoxic system for biomedical applications

• Hanieh Shirazi,
• Maryam Daneshpour,
• Soheila Kashanian and
• Kobra Omidfar

Beilstein J. Nanotechnol. 2015, 6, 1677–1689, doi:10.3762/bjnano.6.170

• seemed that the magnetic nanoparticles were rather embedded in a chitosan matrix. According to the hysteresis curves (Figure 1c), the saturation magnetization (Ms) of TMC/Fe3O4 nanoparticles was 59.15 emu/g, which was notably higher than 33.65 emu/g found for the chitosan/Fe3O4 nanoparticles. Both of

• percentage of the viability of the control culture [48][54]. (a) TEM image of uncoated Fe3O4 nanoparticles and their (b) corresponding particle size distribution. (c) Hysteresis loop of the synthesized magnetic nanoparticles: (1) Fe3O4, (2) TMC/Fe3O4, (3) Au/TMC/Fe3O4, (4) chitosan/Fe3O4 and (5) Au/chitosan

Structural and magnetic properties of iron nanowires and iron nanoparticles fabricated through a reduction reaction

• Marcin Krajewski,
• Wei Syuan Lin,
• Hong Ming Lin,
• Katarzyna Brzozka,
• Sabina Lewinska,
• Natalia Nedelko,
• Anna Slawska-Waniewska,
• Jolanta Borysiuk and
• Dariusz Wasik

Beilstein J. Nanotechnol. 2015, 6, 1652–1660, doi:10.3762/bjnano.6.167

• exactly the same ‘histories’ and according to the results of structural studies, they have almost similar structures. Thus, presented results of magnetic measurements reflect the realistic behaviours of both nanostructures. Figure 6a and Figure 6b present the magnetization hysteresis of Fe NWs and Fe NPs

• application of the external magnetic field during the fabrication process. This indicates that during analysis of the hysteresis parameters it is also needed to consider the possible mechanisms of magnetization reversal besides the impact of simple anisotropy. According to the TEM measurements, the

• b) iron nanoparticles with regards to structural experimental results. a) Magnetization hysteresis loops of iron nanowires and nanoparticles at room temperature (Inset – magnification of hysteresis); b) Normalized magnetization hysteresis loops of both studied nanostructures; c) Magnetization as a

Nanomechanical humidity detection through porous alumina cantilevers

• Olga Boytsova,
• Alexey Klimenko,
• Vasiliy Lebedev,
• Alexey Lukashin and
• Andrey Eliseev

Beilstein J. Nanotechnol. 2015, 6, 1332–1337, doi:10.3762/bjnano.6.137

• + 0.00198H)−1/2 (red line), which correlates well with Equation 1. The humidity sensitivity of the AAO cantilever in the linear range estimated by the slope of the experimental curve equals about 100 Hz/%. Hysteresis was not observed for the considered range close to equilibrium. The resonance frequency for

Influence of the shape and surface oxidation in the magnetization reversal of thin iron nanowires grown by focused electron beam induced deposition

• Luis A. Rodríguez,
• Lorenz Deen,
• Rosa Córdoba,
• César Magén,
• Etienne Snoeck,
• Bert Koopmans and
• José M. De Teresa

Beilstein J. Nanotechnol. 2015, 6, 1319–1331, doi:10.3762/bjnano.6.136

• . All results shown in Figure 2 correspond to the average of more than 100 hysteresis loops. Given the sharp switching transitions observed, a high level of reproducibility can be inferred. The observed decrease of HC with the width was also observed in polycrystalline cobalt nanowires grown by FEBID

• 250 nm width and varying thickness. MOKE results. (a) Average magnetic hysteresis loop of the sample with width/nominal thickness of 250 nm/10 nm. (b) Average magnetic hysteresis loop of the sample with width/nominal thickness of 250 nm/35 nm. (c) Coercive field as a function of width for batch 1

Structural transitions in electron beam deposited Co–carbonyl suspended nanowires at high electrical current densities

• Gian Carlo Gazzadi and
• Stefano Frabboni

Beilstein J. Nanotechnol. 2015, 6, 1298–1305, doi:10.3762/bjnano.6.134

• line), a different behavior appears: an hysteresis between [0,2 V] and [2,0 V] data is present, the return curve having higher currents with respect to the first leg. The negative bias portions reflect the return curve trend and do not show any hysteresis. The observed effect might be linked to some

Magnetic properties of iron cluster/chromium matrix nanocomposites

• Arne Fischer,
• Robert Kruk,
• Di Wang and
• Horst Hahn

Beilstein J. Nanotechnol. 2015, 6, 1158–1163, doi:10.3762/bjnano.6.117

• shift of the hysteresis loops recorded after field cooling the samples from temperatures above the Néel temperature (TN) of CoO. Since its discovery the EB has been observed in numerous FM/AFM combinations such as core/shell clusters [5][6], thin film systems [7][8] and also cluster/matrix combinations

• -field cooled/field cooled (ZFC/FC) magnetization measurements and magnetic hysteresis loops recorded in a commercial superconducting quantum interference device (SQUID, Quantum Design) magnetometer. The ZFC/FC curves were collected with an applied external magnetic field of μ0H = 20 mT in a temperature

• interactions) become dominant. Hysteresis loops were recorded at 5 K after field cooling from 350 K, which is above the TN of Cr (311 K [16]), in an external magnetic field of μ0H = 4.5 T. A linear diamagnetic background originating from the Si substrate as well as the Au layers was subtracted. The coercivity

Tunable magnetism on the lateral mesoscale by post-processing of Co/Pt heterostructures

• Oleksandr V. Dobrovolskiy,
• Maksym Kompaniiets,
• Roland Sachser,
• Fabrizio Porrati,
• Christian Gspan,
• Harald Plank and
• Michael Huth

Beilstein J. Nanotechnol. 2015, 6, 1082–1090, doi:10.3762/bjnano.6.109

• heterostructures on the lateral mesoscale. By means of in situ post-processing of Pt- and Co-based nano-stripes prepared by focused electron beam induced deposition (FEBID) we are able to locally tune their coercive field and remanent magnetization. Whereas single Co-FEBID nano-stripes show no hysteresis, we find

• the sample plane and, hence, the out-of-plane magnetization was probed by the measurements. This means that first the shape anisotropy of the stripe had to be overcome and all recorded loops relate to the hard-axis magnetization behavior. The reference Co-based sample A shows no hysteresis, whereby U

• (H) is nearly linear from −1.5 T to 1.5 T and saturates at Hs = ±1.7 T. The U(H) curve of the Co/Pt-based sample B demonstrates two distinctive features compared to sample A: Sample B shows a noticeable hysteresis loop and its saturation field Hs is by about 30% smaller than Hs for sample A. The

From lithium to sodium: cell chemistry of room temperature sodium–air and sodium–sulfur batteries

• Philipp Adelhelm,
• Pascal Hartmann,
• Conrad L. Bender,
• Martin Busche,
• Christine Eufinger and
• Juergen Janek

Beilstein J. Nanotechnol. 2015, 6, 1016–1055, doi:10.3762/bjnano.6.105

• , Co, Fe, etc.) or Mg, and X is an anion (F, O, S, etc.). The overall success has been limited as conversion reactions typically show large irreversible capacities during the first cycle and a large hysteresis during cycling. This irreversible capacity is mostly caused by the need for complete lattice

• reported by Sun et al., and the cells show a type 3A hysteresis (see Figure 4) with a charge potential as low as 3.5 V [41]. 2.3.1.2 Electrolyte instability: Liquid aprotic electrolytes containing carbonate-based solvents such as propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC

• tetrathiafulvalene (TTF) as RM with redox potentials, TTF/TTF+ and TTF+/TTF2+, of 3.4 to 3.7 V. With TTF in a DMSO:LiClO4 electrolyte the Li/O2 cells showed a Type 1C hysteresis and significantly improved kinetics for the charge process. In addition e−/O2 ratios very close to two, as expected for Li2O2 oxidation

Stiffness of sphere–plate contacts at MHz frequencies: dependence on normal load, oscillation amplitude, and ambient medium

• Jana Vlachová,
• Rebekka König and
• Diethelm Johannsmann

Beilstein J. Nanotechnol. 2015, 6, 845–856, doi:10.3762/bjnano.6.87

• closely related to what was reported in [28] and [29]. Differing from many experiments performed with AFM [30][31], the contacts here have a substructure and it is this substructure, which gives rise to the phenomena under discussion. Also, hysteresis is more important in QCM experiments than in AFM

Stick–slip behaviour on Au(111) with adsorption of copper and sulfate

• Nikolay Podgaynyy,
• Sabine Wezisla,
• Christoph Molls,
• Shahid Iqbal and
• Helmut Baltruschat

Beilstein J. Nanotechnol. 2015, 6, 820–830, doi:10.3762/bjnano.6.85

• resolution on Au(111) (no transition to non-stick–slip at this potential); FN = −5, 4, 30 nN; E = 250 mV; scan rate 154 nm/s. (In this image, the apparent gradual change of the lattice direction at the beginning of the upward scan – lower part of the image – is an artefact probably due to the hysteresis of

Capillary and van der Waals interactions on CaF₂ crystals from amplitude modulation AFM force reconstruction profiles under ambient conditions

• Annalisa Calò,
• Oriol Vidal Robles,
• Sergio Santos and
• Albert Verdaguer

Beilstein J. Nanotechnol. 2015, 6, 809–819, doi:10.3762/bjnano.6.84

• to a purely conservative attractive interaction (ΔΦ) can be used to distinguish between dissipative processes (hysteresis, viscosity) occurring in non-contact [37]. In this work, we used the Sader–Jarvis–Katan method [38][39] to reconstruct force vs minimum distance of approach (Fts vs dmin) curves

•  11 suppose a don/doff mechanism. They act at a distance d < don on tip approach and at d < doff on tip retraction, with doff ≥ don [14]. The difference between these two distances leads to hysteresis in the long range. That is, as the tip approaches the sample a capillary bridge forms at d = don

• , which ruptures on tip retraction at d = doff. If the distances of formation and rupture of the capillary bridge do not coincide, i.e., if doff > don, hysteresis occurs and energy is dissipated in the interaction. If doff = don there is no hysteresis and the interaction is conservative [14]. In the

Applications of three-dimensional carbon nanotube networks

• Manuela Scarselli,
• Paola Castrucci,
• Francesco De Nicola,
• Ilaria Cacciotti,
• Francesca Nanni,
• Emanuela Gatto,
• Mariano Venanzi and
• Maurizio De Crescenzi

Beilstein J. Nanotechnol. 2015, 6, 792–798, doi:10.3762/bjnano.6.82

• Figure 4b, with no observable roll-off angle, even when the substrate is turned upside down, see Figure 5a. Therefore, we infer that the contact angle hysteresis is sufficiently high to pin the water droplet on the MWCNT surface. It is possible to estimate the adhesive force in length units of a surface

Magnetic properties of self-organized Co dimer nanolines on Si/Ag(110)

• Lisa Michez,
• Kai Chen,
• Fabien Cheynis,
• Frédéric Leroy,
• Alain Ranguis,
• Haik Jamgotchian,
• Margrit Hanbücken and
• Laurence Masson

Beilstein J. Nanotechnol. 2015, 6, 777–784, doi:10.3762/bjnano.6.80

• nanolines X-ray absorption spectroscopy (XAS) spectra were recorded at normal incidence in a magnetic field of 6 T for parallel (σ+) and antiparallel (σ−) alignment of the X-ray helicity with respect to the sample magnetization. Magnetic hysteresis measurements at the L3 resonance confirm that the sample

• structure is therefore used to study the magnetic anisotropy in the Co nanolines. The hysteresis loops, obtained from the XMCD signal, were recorded at 4 K for different angles Θ varying from normal incidence (Θ = 0°) to grazing incidence (Θ = 70°) using the measurement geometry presented in Figure 4b. Note

• that at grazing incidence, the magnetic field is oriented perpendicularly to the Co lines. The hysteresis loops for the two extreme configurations (Θ = 0° and 70°) are presented in Figure 4a and the details of the zero-field region show an opening in the M–H curve recorded at Θ = 70°. The square shape

Manipulation of magnetic vortex parameters in disk-on-disk nanostructures with various geometry

• Maxim E. Stebliy,
• Alexander G. Kolesnikov,
• Alexey V. Ognev,
• Alexander S. Samardak and
• Ludmila A. Chebotkevich

Beilstein J. Nanotechnol. 2015, 6, 697–703, doi:10.3762/bjnano.6.70

• -optical Kerr effect (MOKE) magnetometer are supported by the magnetic force microscopy imaging and micromagnetic simulations. Keywords: hysteresis; magnetic vortex; magnetization reversal; micromagnetic structure; Introduction Magnetic nanostructures have a wide range of unique properties that

• Ms is the saturation magnetization) and the hysteresis loop is open (Figure 1c, loop ). There are two local maxima at φ = 0 and 180° surrounded by two minima, Figure 1b. In the field, aligned at an angles 0 and 180°, the hysteresis loop has an inverted shape, i.e., Mr/Ms < 0. The maximum change of Mr

• /Ms was observed in nanostructures with s = 170 nm. To understand the physics of magnetization reversal in disk-on-disk nanostructures, micromagnetic simulations and MFM measurements were conducted. Calculated hysteresis loops are shown in the bottom row of Figure 1c. As can be observed seen, the

Palladium nanoparticles anchored to anatase TiO₂ for enhanced surface plasmon resonance-stimulated, visible-light-driven photocatalytic activity

• Kah Hon Leong,
• Hong Ye Chu,
• Shaliza Ibrahim and
• Pichiah Saravanan

Beilstein J. Nanotechnol. 2015, 6, 428–437, doi:10.3762/bjnano.6.43

• Figure 5 and Figure S2 (Supporting Information File 1). As can be seen, all the samples possess a stepwise adsorption and desorption hysteresis, represented by type-IV isotherms, with the characteristics of a mesoporous material [53]. The variations in BET surface area, average pore size and pore volume

Dynamic force microscopy simulator (dForce): A tool for planning and understanding tapping and bimodal AFM experiments

• Horacio V. Guzman,
• Pablo D. Garcia and
• Ricardo Garcia

Beilstein J. Nanotechnol. 2015, 6, 369–379, doi:10.3762/bjnano.6.36

• separated in long range and short range. The user has the option of combining a long range with a short range interaction to produce the full tip–surface force. It is also possible to add one or several non-conservative interactions such as adhesion hysteresis and/or viscoelasticity. We briefly describe the

• occurs. The inset (Figure 3a) shows the coexistence of two amplitude values for the same zc. This coexistence generates a hysteresis loop [11]. We note that in the attractive regime, the phase shift increases from the non-interacting value (90°) with decreasing zc. However, in the repulsive regime

• –surface distance curves for low and high Q values. The inset shows the details of the hysteresis in the amplitude (approaching and retraction cycles). (b) Corresponding phase shift curves. (c) Spectra of the amplitude components taken at zc = 7 nm. The approaching (continuous line) and retraction curves

Exploiting the hierarchical morphology of single-walled and multi-walled carbon nanotube films for highly hydrophobic coatings

• Francesco De Nicola,
• Paola Castrucci,
• Manuela Scarselli,
• Francesca Nanni,
• Ilaria Cacciotti and
• Maurizio De Crescenzi

Beilstein J. Nanotechnol. 2015, 6, 353–360, doi:10.3762/bjnano.6.34

• the contact angle is due to the highly rough and porous surface of our samples. In addition, no roll-off angle value could be measured, evidently due to the high contact angle hysteresis, which pinned the droplets to the surface [2]. In order to better understand the origin of the enhancement provided

Kelvin probe force microscopy in liquid using electrochemical force microscopy

• Liam Collins,
• Stephen Jesse,
• Jason I. Kilpatrick,
• Alexander Tselev,
• M. Baris Okatan,
• Sergei V. Kalinin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2015, 6, 201–214, doi:10.3762/bjnano.6.19

• . Raiteri et al. reported similar hysteretic behavior in the static electrochemical stress experienced for biased Au electrodes in a variety of electrolytes [54]. Umeda et al. also observed similar hysteresis in this bias range for a cantilever above a platinum surface in water [55]. For all bias sweeps

• not viable. In particular, the absence of a unique minimum in Aω and the presence of hysteresis and irreversible reactions at larger biases observed for Au (Figure 1c,d) are fundamental barriers to the proper application of KPFM in milli-Q water and other ionically-active liquids. Bias- and time

• -resolved EcFM The hysteresis observed in Figure 1 illustrates that the response in milli-Q water is more complex than expected from the electrostatic force interactions described by Equations 1–3. This is not surprising as the underlying assumption of a lossless dielectric is no longer valid in the

Multifunctional layered magnetic composites

• Maria Siglreitmeier,
• Baohu Wu,
• Tina Kollmann,
• Martin Neubauer,
• Gergely Nagy,
• Dietmar Schwahn,
• Vitaliy Pipich,
• Damien Faivre,
• Dirk Zahn,
• Andreas Fery and
• Helmut Cölfen

Beilstein J. Nanotechnol. 2015, 6, 134–148, doi:10.3762/bjnano.6.13

• ) magnetometer. Figure 7 illustrates the magnetization loops (magnetization M versus applied field H) of a representative dried hybrid material with a mineral content of 65 wt % after eight mineralization cycles at 293 K and 2 K. At T = 293 K the hysteresis curve shows zero coercivity and zero remanence as it is

• characteristic for superparamagnetic material [39] with a particle size less than 20 nm. Due to magnetic anisotropy the hysteresis curve at T = 2 K shows ferrimagnetic hysteresis. The saturation magnetization for all analyzed samples is around 26 emu/g at 298 K and 36 emu/g at 2 K which are similar values

• properties, samples with a particle load of 15 wt % to 65 wt % have been analyzed. For all analyzed samples similar results for the magnetic hysteresis as well as for the saturation magnetization have been obtained. Therefore, we conclude that the mineral content as well as the transfer of the synthesis