Size-dependent density of zirconia nanoparticles

• Agnieszka Opalinska,
• Iwona Malka,
• Wojciech Dzwolak,
• Tadeusz Chudoba,
• Adam Presz and
• Witold Lojkowski

Beilstein J. Nanotechnol. 2015, 6, 27–35, doi:10.3762/bjnano.6.4

• films depends on the number of surface –OH groups. Moreover, the –OH groups on the nanomaterial surface can influence the surface reactivity and wetting [26]. Since hydroxy groups greatly affect the properties of zirconia nanoparticles, detecting their surface concentration and optimizing the synthesis

Exploring plasmonic coupling in hole-cap arrays

• Thomas M. Schmidt,
• Maj Frederiksen,
• Vladimir Bochenkov and
• Duncan S. Sutherland

Beilstein J. Nanotechnol. 2015, 6, 1–10, doi:10.3762/bjnano.6.1

• heating the particles to temperatures close to and above the glass transition of polystyrene to allow reshaping of the colloid giving increased wetting of the silica surface and thereby reducing the vertical distance between the caps and holes. Any coupling between caps and hole arrays should be strongly

Si/Ge intermixing during Ge Stranski–Krastanov growth

• Alain Portavoce,
• Khalid Hoummada,
• Antoine Ronda,
• Dominique Mangelinck and
• Isabelle Berbezier

Beilstein J. Nanotechnol. 2014, 5, 2374–2382, doi:10.3762/bjnano.5.246

• concentration of about 15 atom %. The Ge distribution in the islands follows a cylindrical symmetry and Ge segregation is observed only in the {113} facets of the islands. The Ge composition of the wetting layer is not homogeneous, varying from 5 to 30 atom %. Keywords: atom probe tomography; germanium islands

• ][2][3][4][5][6][35], the composition and the thickness of the wetting layer (WL) are still under discussion due to Si/Ge intermixing during growth [10][11][25]. In the present work, pulsed laser atom probe tomography (APT) has been used to quantitatively study (at the atomic scale and in the 3D space

• ) and perpendicular to a {113} facet (solid line). In both profiles, the surface wetting layer, with a Ge composition of about 10 atom %, can be observed. In the case of the {111} facet, the Ge concentration in the island is almost constant, at approximately 14 atom %. The {113} facet also exhibits a

Inorganic Janus particles for biomedical applications

• Isabel Schick,
• Steffen Lorenz,
• Dominik Gehrig,
• Stefan Tenzer,
• Wiebke Storck,
• Karl Fischer,
• Dennis Strand,
• Frédéric Laquai and
• Wolfgang Tremel

Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244

• easily be transferred to Janus particles: Independently, which metal oxide was grown on gold seeds, the metal oxide domain could be encapsulated selectively by SiO2 using a reverse microemulsion technique (Scheme 1) [38][39]. Due to the different chemical wetting behavior of gold and the metal oxide

Liquid-phase exfoliated graphene: functionalization, characterization, and applications

• Mildred Quintana,
• Jesús Iván Tapia and
• Maurizio Prato

Beilstein J. Nanotechnol. 2014, 5, 2328–2338, doi:10.3762/bjnano.5.242

• graphene sheets. For example, graphene can be produced by supercritical solvent exfoliation of graphite. In this procedure, solvents reach or exceed their critical point, presenting outstanding wetting properties, low interfacial tension, low viscosity, and high diffusion coefficients. Under these

UHV deposition and characterization of a mononuclear iron(III) β-diketonate complex on Au(111)

• Irene Cimatti,
• Silviya Ninova,
• Valeria Lanzilotto,
• Luigi Malavolti,
• Luca Rigamonti,
• Brunetto Cortigiani,
• Matteo Mannini,
• Elena Magnano,
• Federica Bondino,
• Federico Totti,
• Andrea Cornia and
• Roberta Sessoli

Beilstein J. Nanotechnol. 2014, 5, 2139–2148, doi:10.3762/bjnano.5.223

• same units (see Figure S1 in Supporting Information File 1). The situation is different for STM images corresponding to the saturation coverage, that is, t6 and t7 (see Figure 6). Both samples are characterized by a wetting layer whose dendritic morphology is reminiscent of the second layer disordered

• coverages on top of a wetting layer. The comparison of the experimental topography with DFT-simulated STM images of the pristine Fe(dpm)3 complex, as well as those of two possible fragments, suggests that the observed tetra-lobed features are compatible with the formation of Fe(dpm)2 species on the surface

Properties of plasmonic arrays produced by pulsed-laser nanostructuring of thin Au films

• Katarzyna Grochowska,
• Katarzyna Siuzdak,
• Peter A. Atanasov,
• Carla Bittencourt,
• Anna Dikovska,
• Nikolay N. Nedyalkov and
• Gerard Śliwiński

Beilstein J. Nanotechnol. 2014, 5, 2102–2112, doi:10.3762/bjnano.5.219

• nanostructuring, the grainy, thin metal film sputtered onto the substrate (e.g., glass, ITO, or Si) is melted and fragmented by irradiation with laser pulses under defined conditions. The film fragmentation starts at the grain boundaries. The poor wetting of the substrate by the liquid metal, in this case Au, and

• postulated how the NP shapes depend on the equilibrium of the surface tension forces [34]. The partially spherical/spheroidal shapes correspond to the case of partial wetting of the substrate by the molten metal and are characterized by a contact angle value of less than 90°. This angle approaches 180° in

• the case of weak wetting, that is, with a decrease in the metal–substrate interface. While a variety of NP shapes can be easily considered by means of numerical methods (see, e.g., the results discussed in [35][36]), analytical approaches based on Mie theory with a Drude model of the metallic sphere

Nanomanipulation and environmental nanotechnology

• Enrico Gnecco,
• Andre Schirmeisen,
• Carlos M. Pina and
• Udo Becker

Beilstein J. Nanotechnol. 2014, 5, 2079–2080, doi:10.3762/bjnano.5.216

• processes. For example, the photocatalytic degradation of pollutants can be interpreted using density functional theory. On a different scale, AFM measurements in liquid environments can be supported by advanced contact mechanics models including the squeeze-out of wetting fluids. Adhesion of fluorite

Cathode lens spectromicroscopy: methodology and applications

• T. O. Menteş,
• G. Zamborlini,
• A. Sala and
• A. Locatelli

Beilstein J. Nanotechnol. 2014, 5, 1873–1886, doi:10.3762/bjnano.5.198

• micrometer-sized Fe3O4 islands on a FeO wetting layer. The combination of spatially-resolved XPS and XAS spectra, along with μ-LEED patterns, allowed the unequivocal identification of the specific iron-oxide phases. From the screening of substrate core-level photoelectrons, the thickness of the micrometer

• . In the above example of FeOx growth on Ru(0001), further oxidation by using NO2 as atomic oxygen source resulted in the transformation of the FeO wetting layer to hematite (α-Fe2O3) and the triangular Fe3O4 islands to maghemite (γ-Fe2O3) [71]. In an independent study, the real-time observation of

• islands and the FeO wetting layer on Ru(0001). Top panels show the island and magnetization distribution within a region of 30 μm diameter, illuminated homogeneously by vertically scanning the photon beam during acquisition. Bottom panels

Experimental techniques for the characterization of carbon nanoparticles – a brief overview

• Wojciech Kempiński,
• Szymon Łoś,
• Mateusz Kempiński and
• Damian Markowski

Beilstein J. Nanotechnol. 2014, 5, 1760–1766, doi:10.3762/bjnano.5.186

• the CN size [40][41]. Water seems to cause a slightly larger shrinkage of the CNs than CCl4, probably due to the large difference in wetting of graphitic pore walls by both liquids. The wetting in porous materials is commonly described with the microscopic wetting parameter α [42], which shows the

• interplay between the interactions within the liquid and of the liquid within the pore walls. The wetting parameter is given as: where c is a constant that comprises the parameters related to the structure of the pore walls and ε is the energy parameter in the Lennard–Jones potential, where the index fw

Surface topography and contact mechanics of dry and wet human skin

• Alexander E. Kovalev,
• Kirstin Dening,
• Bo N. J. Persson and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2014, 5, 1341–1348, doi:10.3762/bjnano.5.147

• cellulose fibers. In fact, cellulose fibers exhibit elastoplastic properties very similar to the stratum corneum: Both absorb water strongly and swell by wetting, both have elastic moduli of the order of 10 MPa in the wet state and of the order of 1 GPa in the dry state [11]. The swelling (and elastic

• 0.8 cm/s and a normal load of 0.5 N during wetting/drying. Adopted from [3] with the permission of the authors. The ratio of the contact area A to the area of the nominal contact area A0 as a function of the lower scale magnification ζ included in the calculation in a log10–log10 scale. The blue and

Organic and inorganic–organic thin film structures by molecular layer deposition: A review

• Pia Sundberg and
• Maarit Karppinen

Beilstein J. Nanotechnol. 2014, 5, 1104–1136, doi:10.3762/bjnano.5.123

The study of surface wetting, nanobubbles and boundary slip with an applied voltage: A review

• Yunlu Pan,
• Bharat Bhushan and
• Xuezeng Zhao

Beilstein J. Nanotechnol. 2014, 5, 1042–1065, doi:10.3762/bjnano.5.117

• The drag of fluid flow at the solid–liquid interface in the micro/nanoscale is an important issue in micro/nanofluidic systems. Drag depends on the surface wetting, nanobubbles, surface charge and boundary slip. Some researchers have focused on the relationship between these interface properties. In

• force on the probe were measured on an octadecyltrichlorosilane (OTS) surface with applied voltage. The influence of the surface charge on the boundary slip and drag of fluid flow has been discussed. Finally, the influence of the applied voltage on the surface wetting, nanobubbles, surface charge

• liquid, surface wetting, surface charge, nanobubbles and boundary slip are believed to affect the drag of liquid flow [3][4][5][6][7][8][9][10]. By applying a voltage to the system, the surface wettability can be changed, known as electrowetting, and the surface charge density can be changed as well [11

Insect attachment on crystalline bioinspired wax surfaces formed by alkanes of varying chain lengths

• Elena Gorb,
• Sandro Böhm,
• Nadine Jacky,
• Louis-Philippe Maier,
• Kirstin Dening,
• Sasha Pechook,
• Boaz Pokroy and
• Stanislav Gorb

Beilstein J. Nanotechnol. 2014, 5, 1031–1041, doi:10.3762/bjnano.5.116

• direction. CW, claw; T1, first proximal tarsomere; T2, second proximal tarsomere. Scale bars = 500 μm (a), 20 μm (d,e), 10 μm (b,c). Adapted from [52]. Morphometrical variables of crystals, surface roughness, and wetting properties of wax samples.a Results of statistical analyses (Tukey test performed after

Direct observation of microcavitation in underwater adhesion of mushroom-shaped adhesive microstructure

• Lars Heepe,
• Alexander E. Kovalev and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2014, 5, 903–909, doi:10.3762/bjnano.5.103

• , M.; Gorb, S. J. R. Soc., Interface 2008, 5, 383–385] proposed to explain the strong underwater adhesion of mushroom-shaped adhesive microstructures (MSAMSs). For this purpose, we measured the pull-off forces of individual MSAMSs by detaching them from a glass substrate under different wetting

• smooth glass slide under different wetting conditions with simultaneous video recording of the failure dynamics with a setup similar to a reflection interference contrast microscope (RICM) [23][24]. Individual MSAMSs were cut off from the microstructured tape made from polyvinylsiloxane (PVS) with a

• retraction velocity of 10 µm/s in the direction normal to the surface of the glass slide. In order to test the cavitation hypothesis, pull-off forces were measured at detachment on individual MSAMS samples under different wetting conditions. For sample 1, the following measurement sequence was performed: 1

Measuring air layer volumes retained by submerged floating-ferns Salvinia and biomimetic superhydrophobic surfaces

• Matthias J. Mayser,
• Holger F. Bohn,
• Meike Reker and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2014, 5, 812–821, doi:10.3762/bjnano.5.93

• of the surface structures (Cassie–Baxter wetting state) [13]. The contact angle of water droplets can be equally high in both wetting states [14][15]. However, in the Wenzel wetting state the water is in full contact with the surface and individual droplets adhere firmly [16]. In contrast to this in

• the Cassie wetting state the solid–water interface is strongly reduced while the majority of the interface is between water and air, thereby trapping an air layer between water and surface. As a result the adhesion of the water to the surface is minimised and individual droplets often roll off at very

• low tilting angles. However for true and persisting superhydrophobicity the Cassie wetting state has to be stable, i.e., no wetting transitions should occur [17][18]. One effective solution to prevent wetting transitions are surfaces with multiscale roughness [19][20][21]. Recently potential

The surface microstructure of cusps and leaflets in rabbit and mouse heart valves

• Xia Ye,
• Bharat Bhushan,
• Ming Zhou and
• Weining Lei

Beilstein J. Nanotechnol. 2014, 5, 622–629, doi:10.3762/bjnano.5.73

• constructed on the artifical heart valve’s surface. Then theoretically predicted formulas of the apparent contact angles on such surfaces have been deduced from classical wetting theories. Next the proper geometric parameters of the microstructures that indirectly control the difference of the apparent

Single-asperity contact mechanics with positive and negative work of adhesion: Influence of finite-range interactions and a continuum description for the squeeze-out of wetting fluids

• Martin H. Müser

Beilstein J. Nanotechnol. 2014, 5, 419–437, doi:10.3762/bjnano.5.50

• constraints. This constitutes a continuum model for a contact immersed in a strongly wetting fluid, which can only be squeezed out in the center of the contact through a sufficiently large normal load FN. As for positive work of adhesion, two stable solutions can coexist in a finite range of normal loads. The

• competing solutions can be readily interpreted as contacts with either a load-bearing or a squeezed-out fluid. The possibility for coexistence and the subsequent discontinuous wetting and squeeze-out instabilities depend not only on the Tabor coefficient μT but also on the functional form of the finite

• -range repulsion. For example, coexistence and discontinuous wetting or squeeze-out do not occur when the repulsion decreases exponentially with distance. For positive work of adhesion, the normal displacement mainly depends on FN, Δγ, and μT but – unlike the contact area – barely on the functional form

Exploring the retention properties of CaF₂ nanoparticles as possible additives for dental care application with tapping-mode atomic force microscope in liquid

• Matthias Wasem,
• Joachim Köser,
• Sylvia Hess,
• Enrico Gnecco and
• Ernst Meyer

Beilstein J. Nanotechnol. 2014, 5, 36–43, doi:10.3762/bjnano.5.4

• particles. This correlation between energy dissipation and deflection angle was observed for all three kinds of nanoparticles investigated. Manipulation experiments in liquid have the advantage, compared to measurements in ambient, that the retention of adsorbed particles in not dominated by the wetting

AFM as an analysis tool for high-capacity sulfur cathodes for Li–S batteries

• Renate Hiesgen,
• Seniz Sörgel,
• Rémi Costa,
• Linus Carlé,
• Ines Galm,
• Natalia Cañas,
• Brigitta Pascucci and
• K. Andreas Friedrich

Beilstein J. Nanotechnol. 2013, 4, 611–624, doi:10.3762/bjnano.4.68

• significantly upon 50 cycles as measured by AFM. Differences in transient current and steady-state current indicate the existence of disadvantageously large sulfur particles with thin carbon layers on top. An incomplete wetting of sulfur particles by carbon was also observed by AFM. Another observation was that

Large-scale atomistic and quantum-mechanical simulations of a Nafion membrane: Morphology, proton solvation and charge transport

• Pavel V. Komarov,
• Pavel G. Khalatur and
• Alexei R. Khokhlov

Beilstein J. Nanotechnol. 2013, 4, 567–587, doi:10.3762/bjnano.4.65

• functional groups (Figure 1a). The backbone of Nafion is similar to that of common Teflon [poly(tetrafluoroethylene)] showing pronounced hydrophobic properties. (Teflon is not only insoluble in water but even not wetting with water.) On the contrary, the polar sulfonic acid groups SO3H are strongly

Porous polymer coatings as substrates for the formation of high-fidelity micropatterns by quill-like pens

• Michael Hirtz,
• Marcus Lyon,
• Wenqian Feng,
• Andrea E. Holmes,
• Harald Fuchs and
• Pavel A. Levkin

Beilstein J. Nanotechnol. 2013, 4, 377–384, doi:10.3762/bjnano.4.44

• prevented the SPT from touching the surface in some places) and because of inhomogeneous wetting behaviour due to the fibrous structure of the paper, as seen by sometimes brighter and sometimes fainter features. Overall the rough surface structure prevents clear homogenous patterning of phloxine B, and

• effective in paper-based microfluidics [3]. Patterning on nylon membranes (Figure 4b and Figure 4f) shows a uniform wetting behaviour over the whole substrate area (visible by equal fluorescence intensity in the different features). However, similar distortions, as seen on the paper substrate, caused by the

Near-field effects and energy transfer in hybrid metal-oxide nanostructures

• Ulrich Herr,
• Barat Achinuq,
• Cahit Benel,
• Giorgos Papageorgiou,
• Manuel Goncalves,
• Johannes Boneberg,
• Paul Leiderer,
• Paul Ziemann,
• Peter Marek and
• Horst Hahn

Beilstein J. Nanotechnol. 2013, 4, 306–317, doi:10.3762/bjnano.4.34

• from the simulations. In principle, the observations may be explained by inhomogeneities in the phosphor layer thickness, which might be associated with local variations of the wetting behavior caused by the Ag nanoantennas. Another possible explanation is a quenching of the excitation at the metallic

Selective surface modification of lithographic silicon oxide nanostructures by organofunctional silanes

• Thomas Baumgärtel,
• Christian von Borczyskowski and
• Harald Graaf

Beilstein J. Nanotechnol. 2013, 4, 218–226, doi:10.3762/bjnano.4.22

• oxide nanostructure is much more hydrophilic than the surrounding alkyl monolayer, the wetting of the structure is strongly favored. Recent investigations revealed that there is a pronounced water layer formation on top of the oxide structure due to ambient humidity, which takes place on the time scale

Functionalization of vertically aligned carbon nanotubes

• Eloise Van Hooijdonk,
• Carla Bittencourt,
• Rony Snyders and
• Jean-François Colomer

Beilstein J. Nanotechnol. 2013, 4, 129–152, doi:10.3762/bjnano.4.14

• two-step technique (a mechanical densification of VA-CNT forests followed by a capillarity-driven wetting along the axis of the CNTs). They revealed that the theoretical limit can be approached, i.e., a distance between two neighboring nanotubes