Surface roughness rather than surface chemistry essentially affects insect adhesion

• Matt W. England,
• Tomoya Sato,
• Makoto Yagihashi,
• Atsushi Hozumi,
• Stanislav N. Gorb and
• Elena V. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1471–1479, doi:10.3762/bjnano.7.139

• artificially mimic the properties of surfaces found in nature [1][2][3][4] to produce exceptional wetting/dewetting properties, such as superhydrophobicity, superhydrophilicity, and superoleophobicity (more commonly known as superamniphobicity or superomniphobicity), has been a major topic for research over

• film, and also highly textured (Table 1). Due to these particulate film formation on these surfaces, their Rrms values were extremely high, around three to four orders of magnitude higher than those of the four smooth surfaces, as estimated by a stylus profilometer. Surface dewetting properties were

• agreement with its marked increase in hydrophilicity (superhydrophilicity). Interestingly, the XPS analysis also revealed that the Never Wet surface had the lowest concentration of C (ca. 24 atom %) of any non-perfluorinated sample surface and showed excellent static/dynamic dewetting behavior. In addition

Fast diffusion of silver in TiO₂ nanotube arrays

• Wanggang Zhang,
• Yiming Liu,
• Diaoyu Zhou,
• Hui Wang,
• Wei Liang and
• Fuqian Yang

Beilstein J. Nanotechnol. 2016, 7, 1129–1140, doi:10.3762/bjnano.7.105

• , as shown in Figure 5b. There are Ag nanoparticles present on the outmost surface of the TiO2 nanotubes. The Ag nanofilm became irregular due to the migration of Ag through the TiO2 nanotube arrays and dewetting of the Ag nanofilm, and the topology of TiO2 nanotubes become visible (see Figure S2b in

Assembling semiconducting molecules by covalent attachment to a lamellar crystalline polymer substrate

• Rainhard Machatschek,
• Patrick Ortmann,
• Renate Reiter,
• Stefan Mecking and
• Günter Reiter

Beilstein J. Nanotechnol. 2016, 7, 784–798, doi:10.3762/bjnano.7.70

• crystallization or dewetting may lead to films with a complex morphology that differs substantially from the homogeneous, closed and largely defect-free film, which is required for good charge transport. One has to take into account that differences in device morphology directly translate into differences in

Orientation of FePt nanoparticles on top of a-SiO₂/Si(001), MgO(001) and sapphire(0001): effect of thermal treatments and influence of substrate and particle size

• Martin Schilling,
• Paul Ziemann,
• Zaoli Zhang,
• Johannes Biskupek,
• Ute Kaiser and
• Ulf Wiedwald

Beilstein J. Nanotechnol. 2016, 7, 591–604, doi:10.3762/bjnano.7.52

• monolayers under ultrahigh vacuum conditions at elevated temperatures leading to dewetting [23]. Here, we have chosen the so-called micellar approach delivering well-separated and size-tuneable FePt NPs on flat supports [10][11], which is of special interest for the present experiments since particle

Characterization of spherical domains at the polystyrene thin film–water interface

• Khurshid Ahmad,
• Xuezeng Zhao,
• Yunlu Pan and
• Danish Hussain

Beilstein J. Nanotechnol. 2016, 7, 581–590, doi:10.3762/bjnano.7.51

• reported different phenomena on the PS-coated surface such as dewetting from the silicon surface and formation of nanoindents and blisters [11][25][26][27][28]. It has been shown that the PS film can be dewetted from the silicon surface upon the contact with water [11]. Wang et al. [25] found that the

Nanostructured surfaces by supramolecular self-assembly of linear oligosilsesquioxanes with biocompatible side groups

• Maria Nowacka,
• Anna Kowalewska and
• Tomasz Makowski

Beilstein J. Nanotechnol. 2015, 6, 2377–2387, doi:10.3762/bjnano.6.244

• the amide unit with K+ on the surface of mica. AFM was used to analyse the structure of coated samples (Figure 4). We found that the priming compounds evenly cover the surface. The adherence of the used molecules to mica is very high. Dewetting of the adsorbed materials was not observed and the upper

The Kirkendall effect and nanoscience: hollow nanospheres and nanotubes

• Abdel-Aziz El Mel,
• Ryusuke Nakamura and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2015, 6, 1348–1361, doi:10.3762/bjnano.6.139

• that the nanodroplet tends to split into multiple tiny dewetting metal bismuth nanodroplets. The droplets then migrate and aggregate on the curved inner surface of the oxide shell before the bismuth wets the surface again (between 410.4 and 413.6 s). They attributed this reversible wetting transition

Nanostructuring of GeTiO amorphous films by pulsed laser irradiation

• Valentin S. Teodorescu,
• Cornel Ghica,
• Adrian V. Maraloiu,
• Mihai Vlaicu,
• Andrei Kuncser,
• Magdalena L. Ciurea,
• Ionel Stavarache,
• Ana M. Lepadatu,
• Nicu D. Scarisoreanu,
• Andreea Andrei,
• Valentin Ion and
• Maria Dinescu

Beilstein J. Nanotechnol. 2015, 6, 893–900, doi:10.3762/bjnano.6.92

• ; cross-sectional transmission electron microscopy (XTEM); Introduction Laser pulse processing of surfaces and thin films is a useful tool for purposes such as the amorphous thin films crystallization [1][2][3][4][5][6], surface nanostructuring [7][8][9][10], laser-induced thin film dewetting [11][12

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

• -sized randomly shaped islands is formed. If, after complete evaporation, there is a balance between adhesion and elastic energy, the microstructures are in a stable bent configuration with respect to further wetting–dewetting cycles. This self-assembly leads to an intrinsic hierarchical microstructured

• of the plot) we observe a sharp discontinuity beyond cos θ = 0, confirming again that the transition between the Wenzel and Cassie–Baxter states is not continuous, but it undergoes metastable states which slow down the dewetting process. Actually, by fitting our data in Figure 4b with the hydrophobic

Nanoporous Ge thin film production combining Ge sputtering and dopant implantation

• Jacques Perrin Toinin,
• Alain Portavoce,
• Khalid Hoummada,
• Michaël Texier,
• Maxime Bertoglio,
• Sandrine Bernardini,
• Marco Abbarchi and
• Lee Chow

Beilstein J. Nanotechnol. 2015, 6, 336–342, doi:10.3762/bjnano.6.32

• ). This phenomenon can be explained considering that these crystallites result from the Ge dewetting mechanism occurring on the buried SiO2 layer already observed in Figure 3.3. The general dewetting phenomenon is due to surface/interface energy minimization between the film and the substrate, leading to

• for the fabrication of nanocrystals by dewetting, such as metals or semiconductors. In addition, the structure of the dewetted layers can be controlled using several techniques such as pulsed laser annealing [35][36] or a substrate patterned by focused ion beam. The study of Ge dewetting on SiO2 [37

• ] has already been reported in the literature, however, only in the case of very thin amorphous Ge layers (5−15 nm thick) [38][39][40]. For a large TB, the atomic diffusion length on the surface is significant, and during dewetting, Ge atoms can form large crystallites. In this case, between the

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

• interfacial strain [10]. The main synthetic routes for obtaining inorganic dumbbell-like heterostructures include heterogeneous nucleation [52][53], asymmetric modification at interfaces [41], and non-epitaxial deposition on the full surface of the first nanoparticle followed by thermal dewetting of the shell

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

• . Keywords: Au nanostructures; laser dewetting; laser nanostructuring; plasmonic enhancement; self-organization; Introduction The capability of pulsed-laser beams to deliver energy to a precise space at a precise time stimulated developments of laser technology and a variety of applications in scientific

• noticeable interest in the last two decades [1][2][3][4][5][6][7]. The formation of particulates observed in the case of a Au film irradiated with nanosecond laser pulses has been ascribed by Bischof et al. to the substrate dewetting and two mechanisms were postulated: the nucleation and spinodal

• by Willis and Xu [5]. Using the R–T instability criterion, the dimensions of nanoislands formed by laser-irradiated metal films on Si-supported SiO2 substrate were analyzed by Henley et al. [6][7]. More recently, Kalyanaraman and coworkers discussed the dewetting mechanism basing on hydrodynamic

Towards bottom-up nanopatterning of Prussian blue analogues

• Virgile Trannoy,
• Marco Faustini,
• David Grosso,
• Sandra Mazerat,
• François Brisset,
• Alexandre Dazzi and
• Anne Bleuzen

Beilstein J. Nanotechnol. 2014, 5, 1933–1943, doi:10.3762/bjnano.5.204

• nanoperforated layer. This suggests a dewetting of the gold layer from the silicon surface to form gold droplets between the silicon wafer and the nanoperforated oxide layer corresponding to the light areas. The bottom of the nanoperforations in the dark areas would therefore be made of silicon rather than of

• dewetting of the gold layer from the silicon substrate occurred. In contrast to sample Au10NC, the gold layer still covers a great majority of the surface after the formation of the oxide nanoperforated layer. Figure 4, corresponding to a magnification of the majority of light areas, shows that the AFM and

• perforations. The non-homogeneous and non-planar surface exhibiting a different chemical nature of the bottom of the nanoperforations of the films deposited on a 10 nm thick gold layer, such as sample Au10NC, can be assigned to a dewetting of the gold layer from the silicon during the thermal treatment at 450

Synthesis of Pt nanoparticles and their burrowing into Si due to synergistic effects of ion beam energy losses

• Pravin Kumar,
• Udai Bhan Singh,
• Kedar Mal,
• Sunil Ojha,
• Indra Sulania,
• Dinakar Kanjilal,
• Dinesh Singh and
• Vidya Nand Singh

Beilstein J. Nanotechnol. 2014, 5, 1864–1872, doi:10.3762/bjnano.5.197

• -organized cobalt clusters in a gold substrate upon thermal activation was reported by Padovani et al. [27]. When the surface energy of the metallic film is larger than that of the substrate, then surface nano-structuring is due to ion-induced sputtering of the film followed by the dewetting of metallic

• films deduced by AFM is shown in Figure 2a–e. In high-energy irradiated samples (Figure 2d,e) where Se dominates, the appearance of uniform structures on the surface seems to be due to dewetting of Pt films. Since the kinetic sputtering of the film (dominated by high Sn) is less in these two samples

• its re-deposition on the surface cannot result in such a uniform pattern on the surface. Therefore, transient thermal effects, activated by dewetting, are assumed to yield the uniform surface structures. These surface structures begin to disappear as the Se decreases (see Figure 2c). In the sample

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

• interface may be slightly hydrophobic resulting in a negligible interaction between the counterpart bodies during drying. For more strongly hydrophobic interfaces, e.g., skin in contact with Teflon in water, a dewetting transition may occur resulting in a dry contact area and an effective attraction between

Physical principles of fluid-mediated insect attachment - Shouldn’t insects slip?

• Jan-Henning Dirks

Beilstein J. Nanotechnol. 2014, 5, 1160–1166, doi:10.3762/bjnano.5.127

• -dependent viscous adhesion (Equation 2), the v/h-term in Equation 5 shows that a simple fluid mediated system at rest should not be able to generate any static friction. Based on viscosity estimations from dewetting processes (40 to 150 mPa), Federle et al. showed that the hydrodynamic friction forces

• , the mediating fluid film can become unstable and areas with “dry” solid-like contact can form as a result of local “dewetting” and increased friction forces. Indeed, a similar mechanism has been proposed for the fluid-mediated adhesive toes found in tree frogs, for which force measurements and

• occurrence of dewetting or direct contacts between adhesive pad and surface in smooth or hairy adhesive organs of insects [14][30][31][46]. Conclusion Even after many years of research, several of the fundamental physical properties enabling insects to safely adhere to surfaces are still not fully understood

Synthesis of embedded Au nanostructures by ion irradiation: influence of ion induced viscous flow and sputtering

• Udai B. Singh,
• D. C. Agarwal,
• S. A. Khan,
• S. Mohapatra,
• H. Amekura,
• D. P. Datta,
• Ajay Kumar,
• R. K. Choudhury,
• T. K. Chan,
• Thomas Osipowicz and
• D. K. Avasthi

Beilstein J. Nanotechnol. 2014, 5, 105–110, doi:10.3762/bjnano.5.10

• preparation of the XTEM sample by using focused ion beam. Since the cohesive energy of the metal (Au) is higher than the cohesive energy of the substrate (glass) plus the adhesive energy of the metal on glass, a discontinuous film of Au is formed because of dewetting. The XTEM image (Figure 2) of the sample

• a dewetting of the Au films on PET through sputtering and crater formation. Thus, ion irradiation of NPs synthesized on the surface leads to a burrowing of the NPs into the substrate [23]. However, in all the mentioned works, not all of the phenomena (sputtering, recoiling atoms and viscous flow

• ) responsible for synthesis of NPs embedded in matrix were considered. Ion irradiation of Au thin films on glass leads to the formation of Au nanostructures on the surface due to sputtering, dewetting and surface diffusion. It is also observed from TRIDYN simulations that recoil implantation takes place along

Ordered arrays of nanoporous gold nanoparticles

• Dong Wang,
• Ran Ji,
• Arne Albrecht and
• Peter Schaaf

Beilstein J. Nanotechnol. 2012, 3, 651–657, doi:10.3762/bjnano.3.74

• , 85748 Garching, Germany Center for Micro- and Nanotechnologies, Ilmenau University of Technology, POB 10 05 65, 98684 Ilmenau, Germany 10.3762/bjnano.3.74 Abstract A combination of a “top-down” approach (substrate-conformal imprint lithography) and two “bottom-up” approaches (dewetting and dealloying

• ) enables fabrication of perfectly ordered 2-dimensional arrays of nanoporous gold nanoparticles. The dewetting of Au/Ag bilayers on the periodically prepatterned substrates leads to the interdiffusion of Au and Ag and the formation of an array of Au–Ag alloy nanoparticles. The array of alloy nanoparticles

• size) by varying the period of the structure, total metal layer thickness, and the thickness ratio of the as-deposited bilayers. Keywords: dealloying; dewetting; nanoimprint lithography; nanoparticles; nanoporous gold; ordered arrays; Introduction Metallic nanoparticle arrays are attracting more and

Polymer blend lithography: A versatile method to fabricate nanopatterned self-assembled monolayers

• Cheng Huang,
• Markus Moosmann,
• Jiehong Jin,
• Tobias Heiler,
• Stefan Walheim and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2012, 3, 620–628, doi:10.3762/bjnano.3.71

• potential for their application as templates for the subsequent self-assembly of inorganic materials, for cell-adhesion studies, for laterally controlled dewetting, or for constructive lithography. The extreme flatness (rms roughness below 0.5 nm) allows for a highly sensitive monitoring of growth processes

Directed deposition of silicon nanowires using neopentasilane as precursor and gold as catalyst

• Britta Kämpken,
• Verena Wulf,
• Norbert Auner,
• Marcel Winhold,
• Michael Huth,
• Daniel Rhinow and
• Andreas Terfort

Beilstein J. Nanotechnol. 2012, 3, 535–545, doi:10.3762/bjnano.3.62

• nanoparticles have been tested: the spontaneous dewetting of gold films, thermally annealed gold films, deposition of preformed gold nanoparticles, and the use of “liquid bright gold”, a material historically used for the gilding of porcelain and glass. The latter does not only form gold nanoparticles when

• layer disrupts to form smaller particles, enhancing the NW growth. Raising of the reaction temperature to as high as 900 °C resulted in the deposition of amorphous silicon throughout the reactor. Sputtering and in situ formation of nanoparticles by dewetting To produce more uniform layers of low

• (sample 3). By means of AFM measurements, we determined the deposition rate to be about 10 nm/min. Upon heating these films to 375 °C no obvious changes occurred, while at 650 °C nanostructures formed within 1 h as a result of a dewetting process [28]. As visible in the SEM images (Figure 5), the size and

Dipole-driven self-organization of zwitterionic molecules on alkali halide surfaces

• Laurent Nony,
• Franck Bocquet,
• Franck Para,
• Frédéric Chérioux,
• Eric Duverger,
• Frank Palmino,
• Vincent Luzet and
• Christian Loppacher

Beilstein J. Nanotechnol. 2012, 3, 285–293, doi:10.3762/bjnano.3.32

• intermolecular π-stacking of the organic molecules. Although for certain molecules π-stacking can lead to the formation of one-dimensional wires [3], in general, for organic–inorganic heteroepitaxy (OIHE) on insulating substrates the growth mode is often governed by a dewetting process [4] as the MM interaction

• films on metal substrates, and they are atomically well-defined. Different routes have been proposed to circumvent the problem of dewetting since it is the control of a few, down to even single, homogeneous and well-ordered molecular layers that is desired for many applications in molecular (opto

An NC-AFM and KPFM study of the adsorption of a triphenylene derivative on KBr(001)

• Antoine Hinaut,
• Adeline Pujol,
• Florian Chaumeton,
• David Martrou,
• André Gourdon and
• Sébastien Gauthier

Beilstein J. Nanotechnol. 2012, 3, 221–229, doi:10.3762/bjnano.3.25

• this region as the KBr substrate. The phenomenon observed in Figure 4 can then be attributed to a dewetting process of a molecular layer [4] corresponding to the domain labeled MLh in Figure 4a. Its height of 0.4 nm (profile in Figure 5a) is compatible with the height of a molecule lying flat on the

• allow conclusions to be drawn. More extensive numerical simulations would also be necessary. The measurement of a 0.4 nm height for the MLh monolayer and the high-resolution images of Figure 7 are indicative of a structure composed of molecules lying flat on the surface. The observation of the dewetting

• in the lowest-energy conformation of Figure 9. Note that the molecules are separated enough to avoid van der Waals contact and should be only weakly interacting with each other, confirming our previous suggestion. The images of Figure 4 do not show where the molecules of the dewetting MLh layer go

Self-assembled monolayers and titanium dioxide: From surface patterning to potential applications

• Yaron Paz

Beilstein J. Nanotechnol. 2011, 2, 845–861, doi:10.3762/bjnano.2.94

• 60 nm. Such thin lines were obtained by a dewetting and blow-drying process, which trapped silane solution only in the recesses of the molded stamp. In a different work, OTS was deposited by microcontact printing onto both external sides of a nanoporous polycarbonate filter. As a consequence, the ALD

Micro to nano: Surface size scale and superhydrophobicity

• Christian Dorrer and
• Jürgen Rühe

Beilstein J. Nanotechnol. 2011, 2, 327–332, doi:10.3762/bjnano.2.38

• barrier that opposes drop movement comes from this dewetting process. One of the findings discussed here is that even those surfaces where the solid fraction is relatively high (11%) can become superhydrophobic if the surface size scale is decreased far enough. We explain this observation along the

• following lines: I) We compare the dewetting process for a surface with a large size scale with that for a surface with a smaller size scale, both with the same solid fraction and the same topology. For the surface with the larger roughness features, the receding meniscus has to dewet from fewer, but larger

• surface features. In contrast, for the surface with the smaller size scale, the receding meniscus has to dewet from more, but smaller surface features. The dewetting will probably not take place from all surface features at once, but successively from one roughness feature at a time over the length of the

Formation of precise 2D Au particle arrays via thermally induced dewetting on pre-patterned substrates

• Dong Wang,
• Ran Ji and
• Peter Schaaf

Beilstein J. Nanotechnol. 2011, 2, 318–326, doi:10.3762/bjnano.2.37

• Garching, Germany 10.3762/bjnano.2.37 Abstract The fabrication of precise 2D Au nanoparticle arrays over a large area is presented. The technique was based on pre-patterning of the substrate before the deposition of a thin Au film, and the creation of periodic particle arrays by subsequent dewetting

• induced by annealing. Two types of pre-patterned substrates were used: The first comprised an array of pyramidal pits and the second an array of circular holes. For the dewetting of Au films on the pyramidal pit substrate, the structural curvature-driven diffusion cooperates with capillarity-driven

• diffusion, resulting in the formation of precise 2D particle arrays for films within a structure dependent thickness-window. For the dewetting of Au films on the circular hole substrate, the periodic discontinuities in the films, induced by the deposition, can limit the diffusion paths and lead to the