Structural and tribometric characterization of biomimetically inspired synthetic "insect adhesives"

• Matthias W. Speidel,
• Malte Kleemeier,
• Andreas Hartwig,
• Klaus Rischka,
• Angelika Ellermann,
• Rolf Daniels and
• Oliver Betz

Beilstein J. Nanotechnol. 2017, 8, 45–63, doi:10.3762/bjnano.8.6

• increased flexibility towards substrates of different surface energy and polarity, (ii) their possible non-Newtonian viscosity shifts implying adjustable viscosities [24][25] and (iii) the formation of lipoid shields that prevent the aqueous fraction of an adhesive from desiccation and its sticking to the

When the going gets rough – studying the effect of surface roughness on the adhesive abilities of tree frogs

• Niall Crawford,
• Thomas Endlein,
• Jonathan T. Pham,
• Mathis Riehle and
• W. Jon P. Barnes

Beilstein J. Nanotechnol. 2016, 7, 2116–2131, doi:10.3762/bjnano.7.201

• spherical bead) underneath the tree frog’s foot will lead to an elastic energy penalty associated with the deformation of the toe pad as well as a change in surface energy associated with the interface opening. Assuming the bead and the underlying surface are infinitely stiff compared to the toe pad, only

• the soft toe pad will deform to accommodate the asperity. The total energy (U) of the system is then given by the elastic energy of the toe pad deformation and the surface energy of the opening by Utotal = Uelastic + Usurface. We approximate the elastic energy according to Hertz theory with an

•  10D,E). Gap width was selected as the experimental variable, as this was considered the simplest single parameter to change to view the effects on real contact area and thus adhesive force. PDMS is hydrophobic by nature, and so to cancel out any possible effect that surface energy may have on adhesive

Annealing-induced recovery of indents in thin Au(Fe) bilayer films

• Anna Kosinova,
• Ruth Schwaiger,
• Leonid Klinger and
• Eugen Rabkin

Beilstein J. Nanotechnol. 2016, 7, 2088–2099, doi:10.3762/bjnano.7.199

• the small-slope approximation can be used. The chemical potential of atoms on the surface, µ, is proportional to a local curvature of the surface µ = Ωγκ, where the curvature, κ, is given by and Ω, γ are the atomic volume and the surface energy, respectively. The diffusion flux, j, is proportional to

• between the circles rn by a cone. The chemical potential of atoms on the surface for r = rn is determined as are the variations of the surface energy and the cone volume, respectively, with the displacement of the y-coordinate of the nth circle. Direct calculation yields the following expressions

A novel electrochemical nanobiosensor for the ultrasensitive and specific detection of femtomolar-level gastric cancer biomarker miRNA-106a

• Maryam Daneshpour,
• Kobra Omidfar and
• Hossein Ghanbarian

Beilstein J. Nanotechnol. 2016, 7, 2023–2036, doi:10.3762/bjnano.7.193

• electrochemical characteristics, high surface-to-volume ratio, remarkable surface energy, and great biocompatibility, gold nanoparticles have been one of the most common choices for labeling in electrochemical biosensors [35]. In the present study, we fabricated a simple, sensitive, and specific electrochemical

A new approach to grain boundary engineering for nanocrystalline materials

• Shigeaki Kobayashi,
• Sadahiro Tsurekawa and
• Tadao Watanabe

Beilstein J. Nanotechnol. 2016, 7, 1829–1849, doi:10.3762/bjnano.7.176

• produced by advanced processing methods like various types of deposition methods and used in shape of tiny parts for microelectronic devices. In thin film materials, the application of surface energy-driven grain growth is very useful and powerful for controlling the grain boundary microstructure. When a

• sharp texture is introduced in thin films with help of orientation-dependent surface free energy (namely by applying the surface energy-driven grain growth during annealing), specific low-Σ CSL boundaries can be preferentially introduced, depending on the type and the sharpness of texture [52][128][129

• were designated as Type A, Type B and Type C specimens, respectively. The sharpness of the {111} texture was increased in these specimens by surface energy-driven grain growth during annealing. The Type A specimen had the smallest average grain size of 91 nm and the highest total fraction of low-angle

Monolayer graphene/SiC Schottky barrier diodes with improved barrier height uniformity as a sensing platform for the detection of heavy metals

• Ivan Shtepliuk,
• Jens Eriksson,
• Volodymyr Khranovskyy,
• Tihomir Iakimov,
• Anita Lloyd Spetz and
• Rositsa Yakimova

Beilstein J. Nanotechnol. 2016, 7, 1800–1814, doi:10.3762/bjnano.7.173

• epitaxial graphene layers. The growth of graphene on the carbon face of SiC and 6H polytype results in a barrier height that is higher than that on the Si face and 4H polytype. This can be explained by a difference in surface energy between different interfaces, which governs the growth kinetics and

Nano- and microstructured materials for in vitro studies of the physiology of vascular cells

• Alexandra M. Greiner,
• Adria Sales,
• Hao Chen,
• Sarah A. Biela,
• Dieter Kaufmann and
• Ralf Kemkemer

Beilstein J. Nanotechnol. 2016, 7, 1620–1641, doi:10.3762/bjnano.7.155

• increase of boundaries and surface energy on the surface [10][36]. Many cells show directed migration and a polarized morphology on nano- and microstructured substrates. The process by which cells orient and migrate along the longest axis of a surface feature is called contact guidance [186][216]. Many

Influence of hydrothermal synthesis parameters on the properties of hydroxyapatite nanoparticles

• Sylwia Kuśnieruk,
• Jacek Wojnarowicz,
• Agnieszka Chodara,
• Tadeusz Chudoba,
• Stanislaw Gierlotka and
• Witold Lojkowski

Beilstein J. Nanotechnol. 2016, 7, 1586–1601, doi:10.3762/bjnano.7.153

• in caries therapy [5]. Various studies demonstrate that owing to its high surface energy, nanoscale HAp can enhance its mechanical features, enabling a quicker implant surface turnover [6]. Hydroxyapatite materials are used as substitute bones, antiwrinkle creams, and sun creams. They are used in the

• reduce the matter surface energy by a reduction of the SSA [31] (Table 4). HAp morphology varies depending on the executed process parameters. The synthesis temperature growth (Type 3, 4, 5 and 6) leads to more regular, spherical HAp particles (Figure 5). Numerous reports have proved that synthesis at a

Photothermal effect of gold nanostar patterns inkjet-printed on coated paper substrates with different permeability

• Mykola Borzenkov,
• Anni Määttänen,
• Petri Ihalainen,
• Maddalena Collini,
• Elisa Cabrini,
• Giacomo Dacarro,
• Piersandro Pallavicini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2016, 7, 1480–1485, doi:10.3762/bjnano.7.140

• commonly employed material that combines low-cost and excellent environmental compatibility [20]. Furthermore, the physical and chemical properties of this superb printing substrate (e.g., topography, roughness, stiffness, surface energy, polarity, porosity and pore geometry) can be easily tailored by

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

• is primarily responsible for natural anti-attachment properties has also not been fully resolved. Therefore, a comparative study of the attachment behavior of insects on artificially designed (low/high surface energy) surfaces of varying surface roughness, has been postulated as an effective strategy

• hydrocarbons [26][27][28][29][30][31][32]. Several hypotheses exist on how plant surfaces prevent insect attachment. These are typically based on (1) the reduction of the contact area between the substrate and the insect adhesive pad through surface micro-roughness, (2) a decrease in substrate surface energy

• substrates, as measured by the magnitude of CAs. It also seems that other factors, in addition to the surface energy, influence beetle attachment. These factors are presumably related to the different characters of chemical substances, which may mediate physical and chemical interactions in contact to

Fracture behaviors of pre-cracked monolayer molybdenum disulfide: A molecular dynamics study

• Qi-lin Xiong,
• Zhen-huan Li and
• Xiao-geng Tian

Beilstein J. Nanotechnol. 2016, 7, 1411–1420, doi:10.3762/bjnano.7.132

• fracture strength of pre-cracked MoS2 sheet is where E is Young’s modulus, γs is the surface energy and F(w,a,a) is a function depending on the geometry parameters as defined in Equation 2. In Equation 2 a denotes a half of crack length, w is a half of MoS2 sheet width, and α is the kink angle of crack tip

• effect, are used to estimate the fracture stresses of pre-cracked MoS2 sheets with different crack lengths. The Equation 1 in the preceding section is Griffith's model with finite size effect. The surface energy can be estimated by the difference of potential energy of system before and after fracture

• . However, due to the significant difference between the fracture surface of different simulations, the surface energy varies dramatically (0.5–10 J/m2). With Young’s modulus calculated above and taking the surface energy of MoS2 sheet to be 5 J/m2 for calculating, the results obtained from three continuum

Three-gradient regular solution model for simple liquids wetting complex surface topologies

• Sabine Akerboom,
• Marleen Kamperman and
• Frans A. M. Leermakers

Beilstein J. Nanotechnol. 2016, 7, 1377–1396, doi:10.3762/bjnano.7.129

• possible explanation of the increase in θ on structured surfaces, is air entrapment [12][13]. Air acts as hydrophobic patch (θY for the water/air interface is 180°), and these patches lower the average surface energy of the surface (see Figure 1C) [14][15]. The resulting apparent contact angle for this so

• -called Cassie–Baxter state is then given by [16] with Φs the fraction under the droplet that is in contact with the solid and (1 − Φs) the fraction under the droplet in contact with air. This approach thus defines the solid as a new material with a different effective surface energy on a macroscopic

Reasons and remedies for the agglomeration of multilayered graphene and carbon nanotubes in polymers

• Rasheed Atif and
• Fawad Inam

Beilstein J. Nanotechnol. 2016, 7, 1174–1196, doi:10.3762/bjnano.7.109

• include a large surface-to-volume ratio and a chemical texture of the surface [1][2]. Surfaces are inherently high-energy sites. Because nano-fillers have high a surface area, they also have very high values of surface energy. When the nano-fillers are added to a polymer matrix this high surface energy

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

• the curvature effect on the distribution or wetting of Ag on the surface of the TiO2 nanotubes. According to the Gibbs–Thomson relation [35][36], the equilibrium concentration of solute atoms on a curved surface is determined by the surface energy and the mean curvature. Thus, the equilibrium

Development of highly faceted reduced graphene oxide-coated copper oxide and copper nanoparticles on a copper foil surface

• Rebeca Ortega-Amaya,
• Yasuhiro Matsumoto,
• Andrés M. Espinoza-Rivas,
• Manuel A. Pérez-Guzmán and
• Mauricio Ortega-López

Beilstein J. Nanotechnol. 2016, 7, 1010–1017, doi:10.3762/bjnano.7.93

• predominant inorganic phase in the core of the rGO-coated nanoparticles. Notice that the Cu2O and CuNPs developed a faceted shape, i.e., their equilibrium crystal shape which is determined by the surface energy [32]. Equilibrium crystal shape development In all cases, TEM or FE-SEM images revealed that

Microscopic characterization of Fe nanoparticles formed on SrTiO₃(001) and SrTiO₃(110) surfaces

• Miyoko Tanaka

Beilstein J. Nanotechnol. 2016, 7, 817–824, doi:10.3762/bjnano.7.73

• plane. This type of modified Wulff construction, which takes into account the particle–substrate interaction, is denominated as the Winterbottom construction [58]. The Winterbottom theory describes the dependence of the particle shape upon the anisotropy of the surface energy of the particle and upon

Facile synthesis of water-soluble carbon nano-onions under alkaline conditions

• Gaber Hashem Gaber Ahmed,
• Rosana Badía Laíño,
• Josefa Angela García Calzón and
• Marta Elena Díaz García

Beilstein J. Nanotechnol. 2016, 7, 758–766, doi:10.3762/bjnano.7.67

• into spherical particles composed of concentric graphitic layers (Figure 7), in order to minimize the surface energy of the newly formed edge planes of graphite [9]. Although similar open/closed geodesic structures have been used as models for quantum chemical modelling the growth and the molecular and

Cantilever bending based on humidity-actuated mesoporous silica/silicon bilayers

• Christian Ganser,
• Gerhard Fritz-Popovski,
• Roland Morak,
• Parvin Sharifi,
• Benedetta Marmiroli,
• Barbara Sartori,
• Heinz Amenitsch,
• Thomas Griesser,
• Christian Teichert and
• Oskar Paris

Beilstein J. Nanotechnol. 2016, 7, 637–644, doi:10.3762/bjnano.7.56

• measured cantilever deflection, we assume for simplicity all mesopores being fully empty for the lowest RH (RH < 10%) and fully saturated with water without any menisci (meaning PL = 0 in Equation 3) for the highest RH (RH ≈ 85%). Then, γSL = Δγ is the difference between the surface energy of silica and

• ) and on nanostructural parameters of the film (mean curvature and volume fraction). The only material-dependent properties entering are the Young’s modulus of the substrate and the change of the surface energy of the pore wall material with wetting, which for the silica–water interface is well known

• of surface energy Δγ of silica upon full wetting with water. Acknowledgements Financial support from the Federal Government of Styria in the Framework of the Human Technology Interface: Sensors for Medical Applications (HTI:SMApp) initiative under contract A3-22.M-5/2012-32 is gratefully

Correlative infrared nanospectroscopic and nanomechanical imaging of block copolymer microdomains

• Benjamin Pollard and
• Markus B. Raschke

Beilstein J. Nanotechnol. 2016, 7, 605–612, doi:10.3762/bjnano.7.53

• [6][15][16]. The size of these microdomains (~60 nm, determined by the radial peak of a 2D Fourier transform of AFM topography) is comparable to the film thickness. Towards equilibrium, differences in the surface energy of PS and PMMA lead to the formation of a top surface layer of PS at the air

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

• SiO2 or crystalline sapphire(0001) supports, highly (001)-textured FePt films can be fabricated by rapid thermal processing driven by stress-induced reorientation [21], while longer annealing times on the order of minutes lead to reorientation towards (111) texture due to surface energy-driven

• ) texture already in the as-reduced state as opposed to a 3 nm thick FePt film, which shows such a texture only after annealing at 460 °C for 30 min. By further annealing, this texture can be clearly improved because the symmetry of the surface-energy-favored (111) FePt facets matches the hexagonal symmetry

• change of their random orientation. At this point, it is worth adding a general remark on the competition between surface-energy-related driving forces favoring certain facets during NP growth implying corresponding rotational symmetries and forces that are related to the particle–substrate interface

Nanoscale effects in the characterization of viscoelastic materials with atomic force microscopy: coupling of a quasi-three-dimensional standard linear solid model with in-plane surface interactions

• Santiago D. Solares

Beilstein J. Nanotechnol. 2016, 7, 554–571, doi:10.3762/bjnano.7.49

• AFM simulation. A multifrequency AFM simulation tool based on the above sample model is provided as supporting information. Keywords: atomic force microscopy; modeling; polymers; simulation; spectroscopy; standard linear solid; surface elasticity; surface energy; viscoelasticity; Introduction The

• may be difficult to properly define the surface energy (even conceptually) since the local material constituents (e.g., polymer chains) can significantly differ from their neighbors and can be, to a varying degree, flexible and mobile. At this scale, the surface is not a smooth continuum but may

• dangling bonds on the surface [29]. Loosely speaking (that is, without considering reconstruction and/or relaxation), the surface energy correlates with the number of bonds broken per unit area, divided between the two surfaces that are created (the breaking of the bond requires that the appropriate bond

Early breast cancer screening using iron/iron oxide-based nanoplatforms with sub-femtomolar limits of detection

• Dinusha N. Udukala,
• Hongwang Wang,
• Sebastian O. Wendel,
• Aruni P. Malalasekera,
• Thilani N. Samarakoon,
• Asanka S. Yapa,
• Gayani Abayaweera,
• Matthew T. Basel,
• Pamela Maynez,
• Raquel Ortega,
• Yubisela Toledo,
• Leonie Bossmann,
• Colette Robinson,
• Katharine E. Janik,
• Olga B. Koper,
• Ping Li,
• Massoud Motamedi,
• Daniel A. Higgins,
• Gary Gadbury,
• Gaohong Zhu,
• Deryl L. Troyer and
• Stefan H. Bossmann

Beilstein J. Nanotechnol. 2016, 7, 364–373, doi:10.3762/bjnano.7.33

• -resonance quenching (dipole–surface energy transfer (SET) [20][21]) from TCPP to Fe/Fe3O4 and Förster resonance energy transfer (FRET [20][22]) from TCPP to cyanine 5.5. The latter is permanently tethered to the inorganic nanoparticle. For all of the employed consensus sequences, with the exceptions of

• effect” upon proteolytic cleavage: the fluorophore is switched on due to the increase in distance between the Fe/Fe3O4 core/shell nanoparticle, leading to decreased Förster resonance energy transfer (FRET) [21][24], k1, and dipole–surface energy transfer (SET) [20][22], k2. Further explanations are

Synthesis and applications of carbon nanomaterials for energy generation and storage

• Marco Notarianni,
• Jinzhang Liu,
• Kristy Vernon and
• Nunzio Motta

Beilstein J. Nanotechnol. 2016, 7, 149–196, doi:10.3762/bjnano.7.17

• the solvent molecules [88][89]. In particular, it was discovered that effective solvents are those with a surface energy similar to graphene (≈0–50 mJ m−2) [88]: where ΔHmix is the enthalpy of the mixing, Vmix is the volume of the mixture, TNS is the thickness of a graphene nanosheet, ES,S and ES,G

• sonication [88][90]. Furthermore, some solvents are more suitable because they match the graphene surface energy, such as N,N-dimethylformamide (DMF), benzyl benzoate, γ-butyrolactone (GBL), 1-methyl-2-pyrrolidinone (NMP), N-vinyl-2-pyrrolidone (NVP) and N,N-dimethylacetamide (DMA), while ethanol, acetone

Chemical bath deposition of textured and compact zinc oxide thin films on vinyl-terminated polystyrene brushes

• Nina J. Blumenstein,
• Caroline G. Hofmeister,
• Peter Lindemann,
• Cheng Huang,
• Johannes Baier,
• Andreas Leineweber,
• Stefan Walheim,
• Christof Wöll,
• Thomas Schimmel and
• Joachim Bill

Beilstein J. Nanotechnol. 2016, 7, 102–110, doi:10.3762/bjnano.7.12

• 20 cycle sample. This Volmer–Weber-like growth [41] indicates that the surface energy of Si is smaller than the interface energy between ZnO and SiOx plus the surface energy of ZnO. In the case of the PS template, the growth of a homogeneous film is favored (Figure 5). A representative cross section

Two step formation of metal aggregates by surface X-ray radiolysis under Langmuir monolayers: 2D followed by 3D growth

• Smita Mukherjee,
• Marie-Claude Fauré,
• Michel Goldmann and
• Philippe Fontaine

Beilstein J. Nanotechnol. 2015, 6, 2406–2411, doi:10.3762/bjnano.6.247

• oriented 2D crystals, the irradiation induced the in-plane coalescence of these 2D crystals. One then obtains a 2D crystal with a surface area of approximately 10 µm2 with thickness of about 4.5 nm (equal to the X-ray penetration depth) [4]. However, the surface energy of the two surfaces of this platelet

• should differ since the interfaces are different (water/Ag below and organic molecule/air above). Such difference should induce a curvature of the platelet, which could rupture when the surface energy reaches a critical value. This could lead to the disorientation of the platelets and the formation of