Superhydrophobicity in perfection: the outstanding properties of the lotus leaf

• Hans J. Ensikat,
• Petra Ditsche-Kuru,
• Christoph Neinhuis and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2011, 2, 152–161, doi:10.3762/bjnano.2.19

• ] showed unique properties of the epicuticular wax of the lotus. The high content of nonacosanediols leads to a high melting point as well as a strongly disturbed crystal structure which is the basis for the formation of tubules. The visualization of the contact zone between leaves and droplets with cryo

• heterogeneous contact between surface and water. The contact area depends on the hydrophobicity of the surface and on the pressure of the water or on the kinetic energy or velocity of the striking water drops. At low pressures, caused by resting or rolling water droplets, the contact area is determined by the

• roughly. Water droplets with a radius <100 nm may be able to intrude between the wax tubules; this curvature corresponds to a Laplace pressure of >1.4 MPa (14 bar). Varanasi et al. (2009) [22] calculated the capillary pressures of hydrophobic test samples with structure dimensions roughly similar to those

Capillary origami: superhydrophobic ribbon surfaces and liquid marbles

• Glen McHale,
• Michael I. Newton,
• Neil J. Shirtcliffe and
• Nicasio R. Geraldi

Beilstein J. Nanotechnol. 2011, 2, 145–151, doi:10.3762/bjnano.2.18

• wrapping and relate it to the same transition condition known to apply to superhydrophobic surfaces. The results are given for both droplets being wrapped by thin ribbons and for solid grains encapsulating droplets to form liquid marbles. Keywords: capillary origami; Cassie; contact angle

• = (κb/γLV)1/2 the solid can become deformed and shaped by the liquid. In practice, this effect has been given the name “capillary origami” based on experiments showing how films of polydimethylsiloxane (PDMS) shaped in two-dimensions can be folded by evaporating droplets of water to produce a designed

• roughness factor rW and using the definition of the equilibrium contact angle on a rigid substrate of cosθe = (γSV − γSL)/γLV gives, Defining the Cassie–Baxter combination cosθCB = φscosθe − (1−φs), which is familiar from the modelling of droplets on superhydrophobic surfaces, gives, The similarity of

Biomimetics inspired surfaces for drag reduction and oleophobicity/philicity

• Bharat Bhushan

Beilstein J. Nanotechnol. 2011, 2, 66–84, doi:10.3762/bjnano.2.9

• behavior of oil droplets on various superoleophobic surfaces created in the lab. Keywords: aquatic animals; biomimetics; drag; lotus plants; shark skin; superhydrophobicity; superoleophobicity; Introduction Biologically inspired design, adaptation, or derivation from nature is referred to as ‘biomimetics

• waxes on lotus leaves exist as tubules [10][11]. Water droplets on these hierarchical structured surfaces readily sit on the apex of the nanostructures because air bubbles fill the valleys of the structure under the droplet (Figure 1a). Therefore, these leaves exhibit considerable superhydrophobicity

• . Static contact angle and contact angle hysteresis of a lotus leaf are about 164° and 3°, respectively [12][13]. The water droplets on the leaves remove any contaminant particles from their surfaces when they roll off, leading to self-cleaning [5] and show low adhesive force [14][15][16]. Natural

Single-pass Kelvin force microscopy and dC/dZ measurements in the intermittent contact: applications to polymer materials

• Sergei Magonov and
• John Alexander

Beilstein J. Nanotechnol. 2011, 2, 15–27, doi:10.3762/bjnano.2.2

• the images of the 7M3S blend obtained after the sample was exposed to high humidity (RH > 95%) overnight (Figure 8C). The surface potential image was unchanged but multiple droplets appeared inside the dimples in the topography image. Most likely these are due to condensed water droplets on

• hydrophobic surface of PS-enriched domains. The droplets are characterized by a relatively large wetting angle that indicates hydrophobicity of the underlying locations. Compared to surface potential studies the use of dC/dZ measurements was relatively limited by studies of organic layers [23] and water

Review and outlook: from single nanoparticles to self-assembled monolayers and granular GMR sensors

• Alexander Weddemann,
• Inga Ennen,
• Anna Regtmeier,
• Camelia Albon,
• Annalena Wolff,
• Katrin Eckstädt,
• Nadine Mill,
• Michael K.-H. Peter,
• Jochen Mattay,
• Carolin Plattner,
• Norbert Sewald and
• Andreas Hütten

Beilstein J. Nanotechnol. 2010, 1, 75–93, doi:10.3762/bjnano.1.10

• hydrophobic tails. Such micelles have a size of 1 to 50 nm depending on the tenside concentration [18]. The precursor is confined within these defined droplets which may, thus, act as nanoreactors in which particle growth is initiated. A typical result obtained by the use of an isopropanol/water emulsion and

Flash laser annealing for controlling size and shape of magnetic alloy nanoparticles

• Damien Alloyeau,
• Christian Ricolleau,
• Cyril Langlois,
• Yann Le Bouar and
• Annick Loiseau

Beilstein J. Nanotechnol. 2010, 1, 55–59, doi:10.3762/bjnano.1.7

• demonstrated by the rounded shape of the particles similar to small water droplets on clean glass substrate. The formation of twin boundaries observed on Figure 2c, is characteristic of rapid solidification processes following NPs melting. These laser-induced phenomena tend to reduce the surface energy of the