Contact splitting in dry adhesion and friction: reducing the influence of roughness

• Jae-Kang Kim and
• Michael Varenberg

Beilstein J. Nanotechnol. 2019, 10, 1–8, doi:10.3762/bjnano.10.1

• attachment of the wall-shaped microstructure degrades, regardless of the surface waviness, when the surface roughness increases. Second, splitting the wall-shaped microstructure indeed helps to mitigate the negative effect of the increasing surface unevenness by allowing the split microstructure to adapt

• Spearman’s rank correlation coefficient (−0.97 vs −0.95) than the root-mean-square roughness Rq. This correlation supports our analysis of the relationships between adhesion, roughness and waviness, and proves that the adhesive performance of the wall-shaped microstructure depends on the microscale roughness

• split microstructure exceeds that measured with the original microstructure by an amount that is greater than would be expected by chance. This key finding is demonstrated best in Figure 2c,d, where the roughness increase leads to a less pronounced reduction of the pull-off force if the microstructured

A new bioinspired method for pressure and flow sensing based on the underwater air-retaining surface of the backswimmer Notonecta

• Matthias Mail,
• Adrian Klein,
• Horst Bleckmann,
• Anke Schmitz,
• Torsten Scherer,
• Peter T. Rühr,
• Goran Lovric,
• Robin Fröhlingsdorf,
• Stanislav N. Gorb and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2018, 9, 3039–3047, doi:10.3762/bjnano.9.282

• –water interface allowing a three dimensional reconstruction of that interface (see [18]). The samples were placed in a custom pressure cell allowing defined pressure changes while imaging the air–water interface (Figure 6). Microstructure of the setal bases Different methods were used to analyze the

• microstructure of the setal bases. The hemelytra were cut into several pieces. The pieces were fixed in 2.5% glutaraldehyde and 1.5% osmium tetroxide in cacodylate buffer (380 mOsmol, pH 7.1). After dehydrating in ethanol, the pieces were embedded in Epon 812 via epoxy propane as an intermedium. The clavus and

• trapezium-shaped precut (16 nA/30 kV) was performed and 50 nm thick tomography slices (1 nA/30 kV) covering the area of interest were cut subsequently (see Supporting Information File 1). The resulting stack of images shows the microstructure of the setal bases. One advantage of the FIB slicing technique is

Graphene-enhanced metal oxide gas sensors at room temperature: a review

• Dongjin Sun,
• Yifan Luo,
• Marc Debliquy and
• Chao Zhang

Beilstein J. Nanotechnol. 2018, 9, 2832–2844, doi:10.3762/bjnano.9.264

• , or made “bridges” at the interface between two nanoparticles. Due to the “bridges” existing between TiO2 nanoparticles, the initial resistance of TiO2–rGO sensor was greatly reduced, indicating that the sensor was able to work at room temperature. The partly “wrapping” microstructure enhanced the

Biomimetic surface structures in steel fabricated with femtosecond laser pulses: influence of laser rescanning on morphology and wettability

• Camilo Florian Baron,
• Alexandros Mimidis,
• Daniel Puerto,
• Evangelos Skoulas,
• Emmanuel Stratakis,
• Javier Solis and
• Jan Siegel

Beilstein J. Nanotechnol. 2018, 9, 2802–2812, doi:10.3762/bjnano.9.262

• well defined. In terms of biomimetics, these structures resemble the tiles found on the skin of the Python regius snake, whose microstructure makes it very resistant to damage from wear by reducing friction (c.f. Figure 2E). Laser-based surface texturing has been used to mimic this structure in steel

Optimization of Mo/Cr bilayer back contacts for thin-film solar cells

• Nima Khoshsirat,
• Fawad Ali,
• Vincent Tiing Tiong,
• Mojtaba Amjadipour,
• Hongxia Wang,
• Mahnaz Shafiei and
• Nunzio Motta

Beilstein J. Nanotechnol. 2018, 9, 2700–2707, doi:10.3762/bjnano.9.252

• chromium (Cr) adhesion layer is used as the back contact for a copper zinc tin sulfide (CZTS) thin-film solar cell on a SLG substrate. DC magnetron sputtering is used for deposition of Mo and Cr films. The conductivity of Mo/Cr bilayer films, their microstructure and surface morphology are studied at

• in the range of 0.9 to 1.2 μm [14][15][16], which is 1.5-times the value of our samples. The decreasing of the film resistivity with increasing sputtering power could be attributed to the effect of power on the microstructure of the film. Higher power leads to bigger grain sizes, as higher kinetic

Size-selected Fe₃O₄–Au hybrid nanoparticles for improved magnetism-based theranostics

• Maria V. Efremova,
• Yulia A. Nalench,
• Eirini Myrovali,
• Anastasiia S. Garanina,
• Ivan S. Grebennikov,
• Polina K. Gifer,
• Maxim A. Abakumov,
• Marina Spasova,
• Makis Angelakeris,
• Alexander G. Savchenko,
• Michael Farle,
• Natalia L. Klyachko,
• Alexander G. Majouga and
• Ulf Wiedwald

Beilstein J. Nanotechnol. 2018, 9, 2684–2699, doi:10.3762/bjnano.9.251

• close to that of cell cytoplasm [6][67] thus mimicking the viscosity and microstructure of tissues [68][69]. We measure an increase of the r2-relaxivity from 159 to 495 mM−1·s−1 in water (Figure 5A) and from 118 to 612 mM−1·s−1 in agarose (Figure 5B) for the sample series of MNP-6, MNP-15 and MNP-25

Characterization of the microscopic tribological properties of sandfish (Scincus scincus) scales by atomic force microscopy

• Weibin Wu,
• Christian Lutz,
• Simon Mersch,
• Richard Thelen,
• Christian Greiner,
• Guillaume Gomard and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2018, 9, 2618–2627, doi:10.3762/bjnano.9.243

• Weibin Wu Christian Lutz Simon Mersch Richard Thelen Christian Greiner Guillaume Gomard Hendrik Holscher Institute of Microstructure Technology (IMT), Karlsruhe Institute of Technology (KIT), H.-v.-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany Institute for Applied Materials (IAM

• microstructure. Pieces of skin from the dorsal side have some darker areas while the ventral side is completely opaque. Furthermore, the dorsal scales feature comb-like microsteps while the ventral scales a nearly planar as described by Baumgartner and co-workers [10]. All results presented here were measured

Friction reduction through biologically inspired scale-like laser surface textures

• Johannes Schneider,
• Vergil Djamiykov and
• Christian Greiner

Beilstein J. Nanotechnol. 2018, 9, 2561–2572, doi:10.3762/bjnano.9.238

• effects) have a significant influence on the occurrence of stick–slip motion in biological systems and manufactured structures [21]. Baum et al. additionally focused on investigating the microstructure within the scales and aspects of mechanical interlocking between them. The same group of authors

• microstructure evolution. Another way to understand why these textures demonstrate a non-typical Stribeck curve behaviour for the lubricated experiments might be found in the fact that, compared to classical surface textures, the debris formed during laser texturing was not removed. In fact the scale-like

• ratio of the shear strength to the yield pressure of the softer metal [51]. Consequently, the tribological properties of the surface are strongly influenced by the subsurface material and the subsurface microstructure is strongly influenced by the plasticity and the nature of the corresponding

High-temperature magnetism and microstructure of a semiconducting ferromagnetic (GaSb)_1−x(MnSb)_x alloy

• Leonid N. Oveshnikov,
• Elena I. Nekhaeva,
• Alexey V. Kochura,
• Alexander B. Davydov,
• Mikhail A. Shakhov,
• Sergey F. Marenkin,
• Oleg A. Novodvorskii,
• Alexander P. Kuzmenko,
• Alexander L. Vasiliev,
• Boris A. Aronzon and
• Erkki Lahderanta

Beilstein J. Nanotechnol. 2018, 9, 2457–2465, doi:10.3762/bjnano.9.230

• variations. Contrast changes in the lateral direction are due to diffraction contrast arising from the columnar film microstructure, which was distinctly observed in bright-field TEM (Figure 4a) and in high-resolution bright-field TEM (HRTEM) images (Figure 4b), and even affects the HAADF TEM image (not

• transition of the hexagonal GaSb matrix to a cubic matrix. The electron microscopy data unambiguously shows that the columnar microstructure of the film persists up to almost the surface layers. It should be noted, that no signs of second-phase precipitates in the film volume was observed. In particular

Evidence of friction reduction in laterally graded materials

• Roberto Guarino,
• Gianluca Costagliola,
• Federico Bosia and
• Nicola Maria Pugno

Beilstein J. Nanotechnol. 2018, 9, 2443–2456, doi:10.3762/bjnano.9.229

• nature, or in the local frictional properties, e.g., by controlling the roughness or the microstructure, for the design of advanced sliding interfaces. A reduction in the static friction up to almost 30%, with respect to the corresponding non-graded material, can thus be achieved. Schematic of the

Adhesive contact of rough brushes

• Qiang Li and
• Valentin L. Popov

Beilstein J. Nanotechnol. 2018, 9, 2405–2412, doi:10.3762/bjnano.9.225

• be optimized by controlling the size and shape of the fiber cap [2][3]; this mushroom-shaped microstructure can provide a stronger adhesive performance than the flat punch [4][5]. The compliant fiber is known to increase the strength of adhesion [6][7]. Almost all works in this field are based on the

High-throughput micro-nanostructuring by microdroplet inkjet printing

• Hendrikje R. Neumann and
• Christine Selhuber-Unkel

Beilstein J. Nanotechnol. 2018, 9, 2372–2380, doi:10.3762/bjnano.9.222

• be to combine the benefits of BCML, i.e., the highly controllable generation of regular nanoparticle patterns, with methods that generate an overlay microstructure. In recent years, several methods have been proposed to fabricate such structures, but all of them require several complicated process

Directional light beams by design from electrically driven elliptical slit antennas

• Shuiyan Cao,
• Eric Le Moal,
• Quanbo Jiang,
• Aurélien Drezet,
• Serge Huant,
• Jean-Paul Hugonin,
• Gérald Dujardin and
• Elizabeth Boer-Duchemin

Beilstein J. Nanotechnol. 2018, 9, 2361–2371, doi:10.3762/bjnano.9.221

• emission direction of the beam is determined by the microstructure eccentricity. A very simple, broadband, optical antenna design is used, which consists of a single elliptical slit etched into a gold film. The light beam source is driven by an electrical nanosource of surface plasmon polaritons (SPP) that

• with a minor linear contribution (along the major axis) that increases with eccentricity. Future improvements of these optical antennas include the integration of the electrical SPP nanosource in the design of the microstructure (e.g., as an integrated metal-oxide–metal tunnel junction) and the

Hierarchical heterostructures of Bi₂MoO₆ microflowers decorated with Ag₂CO₃ nanoparticles for efficient visible-light-driven photocatalytic removal of toxic pollutants

• Shijie Li,
• Wei Jiang,
• Shiwei Hu,
• Yu Liu,
• Yanping Liu,
• Kaibing Xu and
• Jianshe Liu

Beilstein J. Nanotechnol. 2018, 9, 2297–2305, doi:10.3762/bjnano.9.214

• [32]. To visually study the microstructure and morphology of Ag2CO3/Bi2MoO6, SEM images of the as-prepared catalysts were taken. Bare Bi2MoO6 presents a hierarchical microsphere structure (diameter: 1.6–3.5 μm, Figure 2a,b). After Ag2CO3 was loaded onto Bi2MoO6, the resulting Ag2CO3/Bi2MoO6 retained

• , and ACO/BMO-50, respectively. For comparison, pure Ag2CO3 was prepared by the same method without the addition of Bi2MoO6. A mixture of Ag2CO3 and Bi2MoO6, symbolized as mixture, was prepared by simple physical mixing. Characterization The microstructure of the samples was observed with a Hitachi S

Nanoscale characterization of the temporary adhesive of the sea urchin Paracentrotus lividus

• Ana S. Viana and
• Romana Santos

Beilstein J. Nanotechnol. 2018, 9, 2277–2286, doi:10.3762/bjnano.9.212

• around 20 nm could clearly be distinguished (Figure 4a,c). These results are consistent with previous reports, describing the sea urchin footprint microstructure, observed by scanning electron microscopy (SEM), as a dense meshwork with smaller mesh-like areas (<1 μm) delimited by very fine fibrils (about

Electrospun one-dimensional nanostructures: a new horizon for gas sensing materials

• Muhammad Imran,
• Nunzio Motta and
• Mahnaz Shafiei

Beilstein J. Nanotechnol. 2018, 9, 2128–2170, doi:10.3762/bjnano.9.202

• 1 µm) [133]. The gas sensing response is also improved without tuning the microstructure of nanofibers just by the introduction of UV irradiation [105][144][145]. The response of TiO2 nanofibers is enhanced from 1.8/25 ppm to 18/25 ppm of hydrogen, whereas the response/recovery time reduced from

Spin-coated planar Sb₂S₃ hybrid solar cells approaching 5% efficiency

• Pascal Kaienburg,
• Benjamin Klingebiel and
• Thomas Kirchartz

Beilstein J. Nanotechnol. 2018, 9, 2114–2124, doi:10.3762/bjnano.9.200

• the chemical composition and microstructure of the Sb2S3 layer. With a focus on the two different hole transport materials P3HT and KP115 shown in Figure 4a, the J–V curves and solar cell performance of the best devices for the two process routes are compared in Figure 4b and Table 1. The Sb-BDC

Direct AFM-based nanoscale mapping and tomography of open-circuit voltages for photovoltaics

• Katherine Atamanuk,
• Justin Luria and
• Bryan D. Huey

Beilstein J. Nanotechnol. 2018, 9, 1802–1808, doi:10.3762/bjnano.9.171

• , microstructure, and performance is necessary as a function of device design, processing, and in-service conditions. Atomic force microscopy (AFM) has been a valuable tool for such characterization, especially of materials properties and device performance at the nanoscale. In the case of thin-film solar cells

• in the microstructure of the thin film. When viewed in 3D, however, the directly acquired photovoltaic properties seem clearly correlated with 3D microstructure. Specifically, the CdTe thin film exhibits profound (orders of magnitude) heterogeneities in local photovoltaic performance within tens of

• statistical and correlative analyses with microstructure and/or other properties. These can only be best revealed by directly measuring VOC*, or for even more sophisticated materials property maps by extension of the straightforward approach presented herein. For instance, with appropriate circuitry that

A visible-light-controlled platform for prolonged drug release based on Ag-doped TiO₂ nanotubes with a hydrophobic layer

• Caihong Liang,
• Jiang Wen and
• Xiaoming Liao

Beilstein J. Nanotechnol. 2018, 9, 1793–1801, doi:10.3762/bjnano.9.170

• (LED) lamp without ultraviolet light (<450 nm), while the other half of tubes with NDM were kept in the dark. Materials characterization The surface morphology and microstructure of the fabricated samples were investigated by scanning electron microscopy (SEM, Hitachi S4800, Japan) and X-ray

Toward the use of CVD-grown MoS₂ nanosheets as field-emission source

• Geetanjali Deokar,
• Nitul S. Rajput,
• Junjie Li,
• Francis Leonard Deepak,
• Wei Ou-Yang,
• Nicolas Reckinger,
• Carla Bittencourt,
• Jean-Francois Colomer and
• Mustapha Jouiad

Beilstein J. Nanotechnol. 2018, 9, 1686–1694, doi:10.3762/bjnano.9.160

• candidates. The FE properties depend on the microstructure of the materials, such as morphology, orientation, size and internal or intrinsic features [1]. Among the different morphologies of 1D and 2D materials, vertically aligned nanostructures are considered as good candidates for field emission. Due to

Light extraction efficiency enhancement of flip-chip blue light-emitting diodes by anodic aluminum oxide

• Yi-Ru Huang,
• Yao-Ching Chiu,
• Kuan-Chieh Huang,
• Shao-Ying Ting,
• Po-Jui Chiang,
• Chih-Ming Lai,
• Chun-Ping Jen,
• Snow H. Tseng and
• Hsiang-Chen Wang

Beilstein J. Nanotechnol. 2018, 9, 1602–1612, doi:10.3762/bjnano.9.152

• the light extraction efficiency (LEE) of the LED [10]. Ding et al. fabricated a LED with enhanced LEE by depositing a patterned sapphire substrate (PSS) on a flip-chip LED with GaN as a base layer [11]. Shei et al. enhanced the LEE of LEDs by 27% by producing a microstructure on the surface of LEDs

• with Ga-doped zinc oxide (GZO)/GaN as the base layer and then reducing the total reflectivity by changing the shape, thickness, and density of the microstructure through dry etching [12]. Li et al. increased the LEE of an InGaN-monolayer quantum-well LED by 1.8–1.9 times relative to that of a

• traditional LED by producing a TiO2 microstructure array on p-GaN through dipping and rapid convective deposition and using noncrystalline TiO2 and anatase TiO2 with a diameter of 520 nm [13]. Huang et al. used Zn and Mg for ion implantation at the GZO thin layer and then adopted rapid thermal annealing to

Correlative electrochemical strain and scanning electron microscopy for local characterization of the solid state electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃

• Nino Schön,
• Deniz Cihan Gunduz,
• Shicheng Yu,
• Hermann Tempel,
• Roland Schierholz and
• Florian Hausen

Beilstein J. Nanotechnol. 2018, 9, 1564–1572, doi:10.3762/bjnano.9.148

• , section JARA-Energy, 52425 Jülich, Germany 10.3762/bjnano.9.148 Abstract Correlative microscopy has been used to investigate the relationship between Li-ion conductivity and the microstructure of lithium aluminum titanium phosphate (Li1.3Al0.3Ti1.7(PO4)3, LATP) with high spatial resolution. A key to

• correlate with the microstructure of the material [17][18][19]. The microstructure describes the relationship between density, porosity and particle size, grain structure and phase composition. These attributes are primarily defined by the sintering process [20] and have been analyzed macroscopically. But

• information about the local mobility of ions, extracted from ESM measurements, are available with very high spatial resolution. Such a correlative microscopy approach allows for direct comparison of microstructure and ionic mobility, enabling unique local insights into the structural, chemical and

Preparation and morphology-dependent wettability of porous alumina membranes

• Dmitry L. Shimanovich,
• Alla I. Vorobjova,
• Daria I. Tishkevich,
• Alex V. Trukhanov,
• Maxim V. Zdorovets and
• Artem L. Kozlovskiy

Beilstein J. Nanotechnol. 2018, 9, 1423–1436, doi:10.3762/bjnano.9.135

• ). This method allows for the study of the microstructure on a set of multiscale AFM and SEM images, covering a wide range of structure element size variations. The SEM images were also analyzed with the graphics editor Image J and ОriginPro8 software packages. With any method of PAM fabrication there are

Ag₂WO₄ nanorods decorated with AgI nanoparticles: Novel and efficient visible-light-driven photocatalysts for the degradation of water pollutants

• Shijie Li,
• Shiwei Hu,
• Wei Jiang,
• Yanping Liu,
• Yu Liu,
• Yingtang Zhou,
• Liuye Mo and
• Jianshe Liu

Beilstein J. Nanotechnol. 2018, 9, 1308–1316, doi:10.3762/bjnano.9.123

• that the diffraction peak intensity of AgI becomes stronger with increasing AgI content, confirming the formation of AgI/Ag2WO4 heterojunctions. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to investigate the morphology and microstructure of AgI/Ag2WO4

• −, small AgI nanoparticles (diameter: 20–40 nm) are uniformly coated on the surface of Ag2WO4 nanorods, signifying the formation of the AgI/Ag2WO4 core–shell heterostructure. To more clearly observe the microstructure of the AgI/Ag2WO4 composite, the TEM and high-resolution TEM (HRTEM) images are shown in

Electrostatic force spectroscopy revealing the degree of reduction of individual graphene oxide sheets

• Yue Shen,
• Ying Wang,
• Yuan Zhou,
• Chunxi Hai,
• Jun Hu and
• Yi Zhang

Beilstein J. Nanotechnol. 2018, 9, 1146–1155, doi:10.3762/bjnano.9.106

• -based devices [6]. Because the microstructure and properties of GO sheets can be greatly manipulated during the reduction process, it is important to characterize and evaluate the reducing effect of different reduction processes. Microelectrode-based electrical conductivity measurements [7] and spectral