Multi-frequency tapping-mode atomic force microscopy beyond three eigenmodes in ambient air

• Santiago D. Solares,
• Sangmin An and
• Christian J. Long

Beilstein J. Nanotechnol. 2014, 5, 1637–1648, doi:10.3762/bjnano.5.175

• accurately for multimodal imaging, it may not be possible to carry out fully quantitative measurements of the surface properties. As already discussed, the tip trajectories for a tetramodal or pentamodal operation are even more complex than the already complex bimodal [19] and trimodal [20] trajectories

• for different free amplitudes and sample parameters; (f) second eigenmode spectra for different free amplitudes. The surface properties were accounted for through a standard linear solid model (see methods section) with K0 = 7.5 N/m, Kinf = 7.5 N/m and Cd = 1 × 10−5 N·s/m for the “soft” sample and K0

In vitro interaction of colloidal nanoparticles with mammalian cells: What have we learned thus far?

• Moritz Nazarenus,
• Qian Zhang,
• Mahmoud G. Soliman,
• Pablo del Pino,
• Beatriz Pelaz,
• Susana Carregal-Romero,
• Joanna Rejman,
• Barbara Rothen-Rutishauser,
• Martin J. D. Clift,
• Reinhard Zellner,
• G. Ulrich Nienhaus,
• James B. Delehanty,
• Igor L. Medintz and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1477–1490, doi:10.3762/bjnano.5.161

• cores are always surrounded by an organic coating [14]. Adsorbed proteins can significantly alter the surface properties of NPs and are of key importance in defining the biological identity of NPs [132][133]. The corona formed around NPs is what the cell will “see” primarily, though certainly also the

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

• between the adhesive pad and the substrate [61]. The classic hydrodynamic model only describes the friction observed with relatively “thick” layers of lubricant (≥0.5 μm, [62]), where neither the specific surface properties (roughness, surface energy) nor Amonton’s law are involved [63]. Friction forces

Trade-offs in sensitivity and sampling depth in bimodal atomic force microscopy and comparison to the trimodal case

• Babak Eslami,
• Daniel Ebeling and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 1144–1151, doi:10.3762/bjnano.5.125

• cases. Finally, we also offer a comparison to the trimodal method [9]. Note that in this paper we use the word sensitivity to qualitatively describe the ability of an eigenmode observable (e.g., phase shift) to detect small changes in the tip–sample forces, which in turn are governed by the surface

• properties. Since much of the discussion is based on the cantilever dynamics, the term can also be understood as the ability of a given cantilever eigenmode to be perturbed by small changes in the external forces when it is oscillating under the specified parameters. Our discussion and conclusions are based

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

• ]. It is also believed that the surface charge density has a relationship with nanobubbles and boundary slip [59][63]. Generally speaking, with an applied voltage, the surface properties and the interaction of the surface and liquid will be affected. In particular, the wettability, surface charge

A nanometric cushion for enhancing scratch and wear resistance of hard films

• Katya Gotlib-Vainshtein,
• Olga Girshevitz,
• Chaim N. Sukenik,
• David Barlam and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2014, 5, 1005–1015, doi:10.3762/bjnano.5.114

• of intense technological interest. The capability to modulate these surface properties while preserving both the bulk properties of the materials and a well-defined, constant chemical composition of the surface is particularly attractive. We report herein the use of a soft, flexible underlayer to

Injection of ligand-free gold and silver nanoparticles into murine embryos does not impact pre-implantation development

• Ulrike Taylor,
• Wiebke Garrels,
• Annette Barchanski,
• Svea Peterson,
• Laszlo Sajti,
• Andrea Lucas-Hahn,
• Lisa Gamrad,
• Ulrich Baulain,
• Sabine Klein,
• Wilfried A. Kues,
• Stephan Barcikowski and
• Detlef Rath

Beilstein J. Nanotechnol. 2014, 5, 677–688, doi:10.3762/bjnano.5.80

• ions, which imply that their toxicity can be reduced by either adapting surface properties or choosing alternative synthesis methods, so that their use could be rendered more safely in a plethora of applications. Experimental Nanoparticle production and characterization The applied laser-based approach

Chemi- vs physisorption in the radical functionalization of single-walled carbon nanotubes under microwaves

• Victor Mamane,
• Guillaume Mercier,
• Junidah Abdul Shukor,
• Jérôme Gleize,
• Aziz Azizan,
• Yves Fort and
• Brigitte Vigolo

Beilstein J. Nanotechnol. 2014, 5, 537–545, doi:10.3762/bjnano.5.63

• to the CNTs. It is recognized to be an efficient way to confer specific surface properties [5]. However, the methods generally used for the covalent functionalization of CNTs often require long reaction times (from several hours to days) [6]. The reaction times can be considerably reduced to a few

Nanoscale patterning of a self-assembled monolayer by modification of the molecule–substrate bond

• Cai Shen and
• Manfred Buck

Beilstein J. Nanotechnol. 2014, 5, 258–267, doi:10.3762/bjnano.5.28

• image, which has to be developed by, for example, conversion into a pattern that exhibits heterogeneous surface properties as illustrated in Figure 1b. As mentioned above this is conveniently done by exploiting the differences in the strength of the S–metal bond between Au and Ag and Cu [25]. While the

Quantum size effects in TiO₂ thin films grown by atomic layer deposition

• Massimo Tallarida,
• Chittaranjan Das and
• Dieter Schmeisser

Beilstein J. Nanotechnol. 2014, 5, 77–82, doi:10.3762/bjnano.5.7

• purity [4]. The growth of TiO2 by ALD is a well-studied process and has been recently reviewed [5]. Charge carrier transport and separation, which strongly depend on interface and surface properties [6][7], are among the most important aspects of energy conversion processes. Therefore the further

Dynamic nanoindentation by instrumented nanoindentation and force microscopy: a comparative review

• Sidney R. Cohen and
• Estelle Kalfon-Cohen

Beilstein J. Nanotechnol. 2013, 4, 815–833, doi:10.3762/bjnano.4.93

Multiple regimes of operation in bimodal AFM: understanding the energy of cantilever eigenmodes

• Daniel Kiracofe,
• Arvind Raman and
• Dalia Yablon

Beilstein J. Nanotechnol. 2013, 4, 385–393, doi:10.3762/bjnano.4.45

• . Keywords: atomic force microscopy; bimodal AFM; cantilever eigenmodes; polymer characterization; Introduction Atomic force microscopy (AFM) has arisen as one of the key tools for characterization of morphology and surface properties of materials (e.g., polymer blends and composites) at the micro

Polynomial force approximations and multifrequency atomic force microscopy

• Daniel Platz,
• Daniel Forchheimer,
• Erik A. Tholén and
• David B. Haviland

Beilstein J. Nanotechnol. 2013, 4, 352–360, doi:10.3762/bjnano.4.41

• measurements [5][6][7][8][9][10] is a strong driving force for the development of atomic force microscopy (AFM). The advent of multifrequency AFM resulted in a variety of new measurement techniques enabling enhanced contrast and spatial mapping of surface properties on a wide range of samples [11]. However

• reconstruction allows for the extraction of properties such as surface adhesion, sample stiffness or interaction geometry. We demonstrate this extraction of surface properties with high-resolution stiffness maps on a blend of polystyrene (PS) and poly(methyl methacrylate) (PMMA). Polynomial reconstruction, and

• reconstruct sharp features in the force curve, such as the force minimum. Surface parameter mapping Material scientists are often interested in determining surface properties with high spatial resolution. ImAFM measurements can be performed while scanning a sample surface [24][25], enabling polynomial force

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

• amplitude–phase–distance curves [40]. From such experiments, the dissipated energy of the AFM tip oscillation can be calculated, which depends on the local elastic and therefore structural surface properties of the substrate. The surface coverage of the relatively rigid silicon oxide with “softer” organic

Photoresponse from single upright-standing ZnO nanorods explored by photoconductive AFM

• Igor Beinik,
• Markus Kratzer,
• Astrid Wachauer,
• Lin Wang,
• Yuri P. Piryatinski,
• Gerhard Brauer,
• Xin Yi Chen,
• Yuk Fan Hsu,
• Aleksandra B. Djurišić and
• Christian Teichert

Beilstein J. Nanotechnol. 2013, 4, 208–217, doi:10.3762/bjnano.4.21

• difference between the 0.22 eV found here and the 0.54 eV can be simply explained by a higher junction temperature induced by the higher current. On the one hand, this “heating” affects the surface properties due to increased desorption, and on the other hand it might lead to a local annealing of the nanorod

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

• applications is the tuning of the CNT surface properties. In this context, functionalization (i.e., the grafting of chemical groups (molecules or particles) on the surface of the nanomaterial) has been reported to give excellent results, with the drawback that it negatively impacts on the alignment of the VA

Catalytic activity of nanostructured Au: Scale effects versus bimetallic/bifunctional effects in low-temperature CO oxidation on nanoporous Au

• Lu-Cun Wang,
• Yi Zhong,
• Haijun Jin,
• Daniel Widmann,
• Jörg Weissmüller and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2013, 4, 111–128, doi:10.3762/bjnano.4.13

• are discussed. Keywords: AuAg alloy; AuCu alloy; CO oxidation; dynamic studies; kinetics; nanoporous Au (NPG) catalyst; oxygen storage capacity (OSC); temporal analysis of products (TAP); Introduction Porous metallic materials with well-controlled morphologies and surface properties have attracted

Friction and durability of virgin and damaged skin with and without skin cream treatment using atomic force microscopy

• Bharat Bhushan,
• Si Chen and
• Shirong Ge

Beilstein J. Nanotechnol. 2012, 3, 731–746, doi:10.3762/bjnano.3.83

• /bjnano.3.83 Abstract Skin can be damaged by the environment easily. Skin cream is an effective and rapid way to moisten the skin by changing the skin surface properties. Rat skin and pig skin are common animal models for studies and were used as skin samples in this study. The nano- and macroscale

• epidermis of pig skin are thicker than those of rat skin. The pig skin has fewer hair follicles than rat skin. Pig skin has been reported to be the most suitable model for human skin because of its similar surface properties, such as body mass and skin-to-body surface-area ratio, sparse hair, thick

• loss of the lipid layer. After the application of skin cream, the skin surface properties change, and the skin is moistened and softened by the skin cream, which leads to a greater ductility and a larger real area of contact resulting in stronger adhesion, such that the coefficient of friction of cream

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

• scanning force microscopy (SFM) techniques allow not only the imaging of the topography of surfaces but also the spatially resolved study of surface properties, such as the electrical, elastic, tribological and wear properties [11][12][13][14][15][16][17][18][19][20][21][22][23]. At the same time, scanning

Mapping mechanical properties of organic thin films by force-modulation microscopy in aqueous media

• Jianming Zhang,
• Zehra Parlak,
• Carleen M. Bowers,
• Terrence Oas and
• Stefan Zauscher

Beilstein J. Nanotechnol. 2012, 3, 464–474, doi:10.3762/bjnano.3.53

• photoresist stripping), processed in parallel, but without thiol deposition. The height, lateral force, and amplitude and phase images do not show any difference in the morphology or the substrate mechanical properties, suggesting that the photoresist developing and stripping steps did not change the surface

• properties. Conclusion We showed that force-modulation microscopy (FMM) can be used to image organic thin films in aqueous environments with high spatial resolution and sensitivity to conformational details that affect the contact mechanics. FMM generated high-contrast amplitude and phase images of proteins

Colloidal lithography for fabricating patterned polymer-brush microstructures

• Tao Chen,
• Debby P. Chang,
• Rainer Jordan and
• Stefan Zauscher

Beilstein J. Nanotechnol. 2012, 3, 397–403, doi:10.3762/bjnano.3.46

• brushes [13] are of increasing importance especially for array-based platforms because of their ability to modify surface properties and their potential applications in surface-based technologies, such as protein-resistant coatings, switchable sensors, substrates for cell-growth control, and for the

Reduced electron recombination of dye-sensitized solar cells based on TiO₂ spheres consisting of ultrathin nanosheets with [001] facet exposed

• Hongxia Wang,
• Meinan Liu,
• Cheng Yan and
• John Bell

Beilstein J. Nanotechnol. 2012, 3, 378–387, doi:10.3762/bjnano.3.44

• current and open-circuit voltage of the DSC. The surface properties of the TiO2 material play an important role in both processes. The process of electron injection in DSCs is controlled by the energy difference between the conduction band of the TiO2 material and the LUMO level of the dye, and the

• applications such as water splitting and lithium-ion batteries [6][7][8]. Further investigation shows that the [001] surface is more beneficial to the photooxidization process through the O− centers compared to the [101] surface, which contains more Ti3+ centers [9]. The different surface properties of the

• sintered TiO2 film (not shown) indicates that the film has the same surface properties as the spheres. J–V characteristics of the DSCs The J–V characteristics of the DSCs with the TiO2 film made from paste A, which contained 13 wt % TiO2 spheres with and without TiCl4 post-treatment, is shown in Figure 2a

Forming nanoparticles of water-soluble ionic molecules and embedding them into polymer and glass substrates

• Stella Kiel,
• Olga Grinberg,
• Nina Perkas,
• Jerome Charmet,
• Herbert Kepner and
• Aharon Gedanken

Beilstein J. Nanotechnol. 2012, 3, 267–276, doi:10.3762/bjnano.3.30

• substrates by a one-step, ultrasound-assisted procedure. The results presented here compare the experimental data collected for the three salts. It is important to note that the applied technique is general and the obtained results appeared to be similar to all studied inorganic salts. Surface properties and

A measurement of the hysteresis loop in force-spectroscopy curves using a tuning-fork atomic force microscope

• Manfred Lange,
• Dennis van Vörden and
• Rolf Möller

Beilstein J. Nanotechnol. 2012, 3, 207–212, doi:10.3762/bjnano.3.23

• about 0.22 eV/cycle. Keywords: atomic force microscopy; energy dissipation; force spectroscopy; hysteresis loop; PTCDA/Ag/Si(111) √3 × √3; Introduction Noncontact atomic force microscopy (NC-AFM) is a powerful tool for the study of surface properties. The invention of the frequency-modulation mode (FM

Noncontact atomic force microscopy study of the spinel MgAl₂O₄(111) surface

• Morten K. Rasmussen,
• Kristoffer Meinander,
• Flemming Besenbacher and
• Jeppe V. Lauritsen

Beilstein J. Nanotechnol. 2012, 3, 192–197, doi:10.3762/bjnano.3.21

• ); polar surfaces; reconstructions; spinel; Introduction While the application of metal oxides in, e.g., catalysis, gas sensors, fuel cells, high-k dielectrics and corrosion protection has seen a very strong development, fundamental research on the surface properties of metal oxides has been a topic of