Effect of tetramethylammonium hydroxide/isopropyl alcohol wet etching on geometry and surface roughness of silicon nanowires fabricated by AFM lithography

• Siti Noorhaniah Yusoh and
• Khatijah Aisha Yaacob

Beilstein J. Nanotechnol. 2016, 7, 1461–1470, doi:10.3762/bjnano.7.138

• at 55–65% relative humidity could produce a thin oxide mask layer with stable and continuous structure on SOI that functioned well as a mask in the subsequent wet chemical etching process. Figure 1 shows that a thin layer oxide mask was patterned into five lines with a width of 165–169 nm, height of

• using AFM lithography (SPI3800N/4000) at a temperature of 24–26 °C with relative humidity of 55–65%. The contact mode, Au cantilever tip (Budgetsensors, Au-coated, ContGB-G) was used at 9 V bias voltage with 0.3 µm/s writing speed. After the AFM lithography process, thin oxide nanowires were formed on

A composite structure based on reduced graphene oxide and metal oxide nanomaterials for chemical sensors

• Vardan Galstyan,
• Elisabetta Comini,
• Iskandar Kholmanov,
• Andrea Ponzoni,
• Veronica Sberveglieri,
• Nicola Poli,
• Guido Faglia and
• Giorgio Sberveglieri

Beilstein J. Nanotechnol. 2016, 7, 1421–1427, doi:10.3762/bjnano.7.133

• structures every 30 s. Measurements were carried out by means of a flow-through technique at atmospheric pressure, using a constant synthetic airflow (0.3 L/min) as carrier gas for the analyte dispersion. During the experiments the relative humidity was 50%. Gas response (R) was defined as [R = (Gf − G0)/G0

• ethanol at a working temperature of 250 °C and in humid air (relative humidity RH = 50% @ 20 °C). Calibration curve for acetone at an operating temperature of 250 °C and in a humid air background (RH = 50% @ 20 °C). The results of the compositional analysis of as-prepared and annealed samples (at 100 and

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

• # = 0.2485. Again these values differ dramatically from our experimental system of water in air at 100% relative humidity. Finally, the interfacial tension in this system is given by γ = 0.03326 in units kBT/b2, which translates with b = 0.2 nm to 3.422 mN/m. This value is smaller than the known value for

Influence of ambient humidity on the attachment ability of ladybird beetles (Coccinella septempunctata)

• Lars Heepe,
• Jonas O. Wolff and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1322–1329, doi:10.3762/bjnano.7.123

• Botanical Garden at Kiel University, Schleswig-Holstein, Germany. They were kept individually in plastic tubes at a temperature of 22–24 °C and relative humidity of 40–50%. These conditions were consistent with those at which the beetles were captured. The beetles were fed with honey. Figure 1 shows the

• atmosphere Traction force experiments were performed in a polymethylmethacrylate (PMMA) chamber (30 × 14 × 14 cm) in which relative humidity could be manipulated by the controlled mixture of dry and wetted air (Figure 2, for details see [14]). For this experiment, three levels of relative humidity (RH) were

• used: 15%, 60% and 99%. The RH was monitored with a P330 digital hygrometer (Dostmann electronic GmbH, Wertheim-Reicholzheim, Germany). To generate humid conditions, air was passed through a water bottle, so that the vapour concentration in the air increased. To reach 99% of relative humidity, slight

Ammonia gas sensors based on In₂O₃/PANI hetero-nanofibers operating at room temperature

• Qingxin Nie,
• Zengyuan Pang,
• Hangyi Lu,
• Yibing Cai and
• Qufu Wei

Beilstein J. Nanotechnol. 2016, 7, 1312–1321, doi:10.3762/bjnano.7.122

• electrochemical workstation (CH Instruments, Shanghai, China) with a three-electrode system. The gas sensing performance of the prepared In2O3/PANI nanofibers was measured using a custom-built static state gas sensing test system at room temperature (25 ± 1 °C) with a relative humidity of 60 ± 1%. During the gas

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

• structures that swell anisotropically and differently between the two layers upon the change of relative humidity (RH) [8]. This bilayer principle has been used to build simple artificial actuators based on the swelling of paper–plastic bilayers [9], and also more general routes have been proposed to create

• reflected from the gold coating of the cantilever onto a split photodiode (Figure 1a). The control of relative humidity was achieved with a custom-built setup where a nitrogen stream is saturated with water in a bubbler and mixed with a dry nitrogen stream [17]. By manually adjusting the flow rates of the

• two streams, the relative humidity can be continuously controlled. The AFM cantilever was mounted inside a closed commercial fluid cell with a volume of about 10 mL. In addition, a Sensirion SHT21 sensor, which records the relative humidity as well as the temperature, is mounted in the fluid cell

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

• ]. However, the tapping phase is also affected by the intermittent formation of a capillary water neck between tip and sample as the cantilever oscillates, which can lead to either net attractive or net repulsive regimes depending on tapping amplitude, relative humidity, and local curvature of the tip and

• relative humidity during the measurement (13%) indicate that we are operating near the threshold between attractive and repulsive regimes [30]. The delicate balance between repulsive capillary forces and overall van der Waals interaction could result in the finer variations across the PMMA microdomain. We

Nanoscale rippling on polymer surfaces induced by AFM manipulation

• Mario D’Acunto,
• Franco Dinelli and
• Pasqualantonio Pingue

Beilstein J. Nanotechnol. 2015, 6, 2278–2289, doi:10.3762/bjnano.6.234

• (relative humidity: 50 to 60% and T = 22–23 °C). How to avoid ripple formation The nanoripple formation can be either a nuisance or an opportunity. In the framework of nanolithography, one should consider the development of tools for creating but also preventing the pattern formation. Regarding this second

• load is constant and equal to 10 nN. Adapted with permission from [31]. Copyright 2001 American Chemical Society. Solvent-enriched polymer films. Examples of 3D ripple structures on PCL (left) and PET (right). The images were obtained in air (relative humidity 40%), with a silicon conical shape tip

Nanofibers for drug delivery – incorporation and release of model molecules, influence of molecular weight and polymer structure

• Jakub Hrib,
• Jakub Sirc,
• Radka Hobzova,
• Zuzana Hampejsova,
• Zuzana Bosakova,
• Marcela Munzarova and
• Jiri Michalek

Beilstein J. Nanotechnol. 2015, 6, 1939–1945, doi:10.3762/bjnano.6.198

• the polymer mixtures at a concentration of 3 wt %. PCL was dissolved in a 1:1 (w/w) mixture of tetrahydrofuran and N,N-dimethylformamide at a concentration of 10 wt %. The electrospinning parameters were 6 rpm, 15 cm and 5.5 kV/cm. The maximum temperature was 30 °C, and the maximum relative humidity

• . PVA was dissolved in water/phosphoric acid at a concentration of 11 wt %. The electrospinning parameters were 2 rpm, 13 cm and 45–55 kV/cm. The relative humidity was 25–30%, and the temperature was 22 °C. The PVA layers were crosslinked thermally in a drying oven at 145 °C for 15 min to reach their

Template-controlled mineralization: Determining film granularity and structure by surface functionality patterns

• Nina J. Blumenstein,
• Jonathan Berson,
• Stefan Walheim,
• Petia Atanasova,
• Johannes Baier,
• Joachim Bill and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2015, 6, 1763–1768, doi:10.3762/bjnano.6.180

• were previously cleaned by CO2 snow-jet treatment (at least 20 s for a 2 × 2 cm substrate). The relative humidity, measured by a Testo 635 Hygrometer, was adjusted to 40–45% during the spin-coating process. For the adjustment of the humidity, a mixture of water-saturated and pure nitrogen were led into

Nanomechanical humidity detection through porous alumina cantilevers

• Olga Boytsova,
• Alexey Klimenko,
• Vasiliy Lebedev,
• Alexey Lukashin and
• Andrey Eliseev

Beilstein J. Nanotechnol. 2015, 6, 1332–1337, doi:10.3762/bjnano.6.137

• ). The shift here is 3900 Hz. Frequency responses of AAO rectangular cantilever (2 μm thick, 800 μm long and 100 μm wide) at relative humidities of 10 and 21% (1120 Hz shift). Resonance frequency of the AAO cantilevers (2 μm thick, 800 μm long and 100 μm wide) as function of relative humidity from 10 to

• shown on Figure 6. The AFM is equipped with vacuum chamber Ar-flow controllers as well as humidity and temperature sensors. The desired moisture level was obtained by controlling the humidity at 25 °C with saturated salt-water and CaCl2 dryer. Saturated salt-water was used to reach high relative

• humidity in the microscope chamber. After stabilization of humidity equilibrium in the system we start measurements of the resonance frequency over a CaCl2 dryer down to the lowest possible humidity level. The microscope determined the upper limit of humidity level. Typically around 10 min have been needed

Polymer blend lithography for metal films: large-area patterning with over 1 billion holes/inch²

• Cheng Huang,
• Alexander Förste,
• Stefan Walheim and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2015, 6, 1205–1211, doi:10.3762/bjnano.6.123

• dissolution in CO2. Preparation of a polymer blend lithographic mask (humidity) The polymer blend films were spin-casted at a speed of ca. 1500 revolutions per minute (rpm) under a relative humidity of 40% onto silicon substrates cleaned by snow jet treatment (at least 20 s for a 2 cm × 2 cm substrate). The

Transformation of hydrogen titanate nanoribbons to TiO₂ nanoribbons and the influence of the transformation strategies on the photocatalytic performance

• Melita Rutar,
• Nejc Rozman,
• Matej Pregelj,
• Carla Bittencourt,
• Romana Cerc Korošec,
• Andrijana Sever Škapin,
• Aleš Mrzel,
• Srečo D. Škapin and
• Polona Umek

Beilstein J. Nanotechnol. 2015, 6, 831–844, doi:10.3762/bjnano.6.86

• concentration began to rise. The system was kept at a temperature of 25 ± 3 °C and a relative humidity of 22 ± 3%. The light source was a 300 W Xe lamp (Newport Oriel Instrument, USA). The lamp imitates the solar spectrum and emits both ultraviolet (UV) and visible light (vis). The radiance intensity on the

Capillary and van der Waals interactions on CaF₂ crystals from amplitude modulation AFM force reconstruction profiles under ambient conditions

• Annalisa Calò,
• Oriol Vidal Robles,
• Sergio Santos and
• Albert Verdaguer

Beilstein J. Nanotechnol. 2015, 6, 809–819, doi:10.3762/bjnano.6.84

• approach when relative humidity is allowed to spontaneously reach the ambient value of about 40% and homogeneous micrometer-sized water patches stabilize on top of the crystals surface. The dissipation induced by the capillary bridge formation is unambiguously identified in experimental Ediss and ΔΦ curves

• no extended water patches were present on the surface. When dry samples were needed, the crystals were kept at 120 °C for 30 min under nitrogen flow before calibrating the cantilevers. In general, repeatedly scanning and/or collecting curves at ambient relative humidity RH ≈ 40% results in the

Conformal SiO₂ coating of sub-100 nm diameter channels of polycarbonate etched ion-track channels by atomic layer deposition

• Nicolas Sobel,
• Christian Hess,
• Manuela Lukas,
• Anne Spende,
• Bernd Stühn,
• M. E. Toimil-Molares and
• Christina Trautmann

Beilstein J. Nanotechnol. 2015, 6, 472–479, doi:10.3762/bjnano.6.48

• were measured on a OCA35 apparatus from Dataphysics Instruments GmbH. Distilled water with a volume of 2 µL was dropped onto the membrane surface at 21 °C and 50% relative humidity of air. Besides ALD coating, the samples were not treated otherwise prior to measurements. Results and Discussion

A scanning probe microscope for magnetoresistive cantilevers utilizing a nested scanner design for large-area scans

• Tobias Meier,
• Alexander Förste,
• Ali Tavassolizadeh,
• Karsten Rott,
• Dirk Meyners,
• Roland Gröger,
• Günter Reiss,
• Eckhard Quandt,
• Thomas Schimmel and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2015, 6, 451–461, doi:10.3762/bjnano.6.46

• ]. If exposed to ambient conditions with a relative humidity of around 40%, the topographic contrast on those two materials disappears in amplitude modulation imaging. The height difference, however, can be observed if the sample is scanned in a liquid [63]. Therefore, we conclude that the vanishing

Boosting the local anodic oxidation of silicon through carbon nanofiber atomic force microscopy probes

• Gemma Rius,
• Matteo Lorenzoni,
• Soichiro Matsui,
• Masaki Tanemura and
• Francesc Perez-Murano

Beilstein J. Nanotechnol. 2015, 6, 215–222, doi:10.3762/bjnano.6.20

• captured and subtracted. All tests are performed at room conditions, with a temperature of 25 °C and under a controlled relative humidity ranging from 20 to 40%. The Si substrates consist of chips cut from Si(100) wafers. Organic contamination on the chips was removed by oxygen plasma etching before the

• voltage is 20 V, relative humidity (RH) is 36%. Results of LAO-AFM on Si with CNF (a) and Si (b) probes as a function of the bias voltage (in V). Writing speed is 1 μm/s, RH is 36%. Monitoring chemical and mechanical stability of CNF probes for LAO-AFM. SEM images before (a) and after (c) the definition

Functionalization of α-synuclein fibrils

• Simona Povilonienė,
• Vida Časaitė,
• Virginijus Bukauskas,
• Arūnas Šetkus,
• Juozas Staniulis and
• Rolandas Meškys

Beilstein J. Nanotechnol. 2015, 6, 124–133, doi:10.3762/bjnano.6.12

• immobilization was allowed to proceed for 5 to 20 min, at 23 °C at a relative humidity of about 45%. The density of fibrillar structures on mica was increased or decreased by the immobilization time or the dilution rate. After adsorption, the surfaces were rinsed with distilled water, dried and visualized using

Synthesis of boron nitride nanotubes and their applications

• Saban Kalay,
• Zehra Yilmaz,
• Ozlem Sen,
• Melis Emanet,
• Emine Kazanc and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9

• humidity sensor system. The adsorption–desorption tests showed that the AgNP–BNNT material had a potentially fast response/recovery time of 100/15 s for the detection of relative humidity at room temperature [90]. The use of Ni-encapsulated BNNTs in optomagnetic-based sensors with respect to their magnetic

Materials and characterization techniques for high-temperature polymer electrolyte membrane fuel cells

• Roswitha Zeis

Beilstein J. Nanotechnol. 2015, 6, 68–83, doi:10.3762/bjnano.6.8

• phosphoric acid. The proton conductivity of the fully doped PBI membrane at 200 °C (0.07 S·cm−1) [23] is almost as high as that of fully hydrated perfluorinated membranes and far less dependent on the relative humidity, thus allowing its use in HT-PEMFCs without humidifying the gas reactants. A HT-PEMFC

• by an activation mechanism that obeys the Arrhenius law [29]. In contrast, the proton conductivity of Nafion is attributed to the vehicle mechanism, which has a weaker temperature dependence. Moreover, the conductivity of acid-doped PBI is less dependent on the relative humidity, although there is a

The capillary adhesion technique: a versatile method for determining the liquid adhesion force and sample stiffness

• Daniel Gandyra,
• Stefan Walheim,
• Stanislav Gorb,
• Wilhelm Barthlott and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2015, 6, 11–18, doi:10.3762/bjnano.6.2

• in Table 1. For each type of hair coating (natural, PDMS- or Teflon-coated ends), the Young’s modulus was the same within the accuracy of the measurement. Its average value was E = (3.04 ± 0.11 ± 0.22) × 105 N/cm2, with the statistical and systematic errors follow the data, respectively. The relative

• humidity during the measurements was roughly RH = 50% and the temperature was 22 °C. Literature values citing Young’s modulus of human head hair are scarce. For example, in [27] a value of 3.89 × 105 N/cm2 (RH = 60%) was indicated. In [28], a range between 1.5 and 4.6 × 105 N/cm2 (RH = 65%) was indicated

Silica nanoparticles are less toxic to human lung cells when deposited at the air–liquid interface compared to conventional submerged exposure

• Alicja Panas,
• Andreas Comouth,
• Harald Saathoff,
• Thomas Leisner,
• Marco Al-Rawi,
• Michael Simon,
• Gunnar Seemann,
• Olaf Dössel,
• Sonja Mülhopt,
• Hanns-Rudolf Paur,
• Susanne Fritsch-Decker,
• Carsten Weiss and
• Silvia Diabaté

Beilstein J. Nanotechnol. 2014, 5, 1590–1602, doi:10.3762/bjnano.5.171

• ALIDA exposure system described in detail by Comouth et al. [18]. For cell exposure the aerosol was humidified to 80–90% relative humidity at 37.5 °C. The humidified aerosol was then carried with identical flows of 100 mL·min−1 (sccm) through six tubes of equal dimensions to the inlets of six exposure

Liquid fuel cells

• Grigorii L. Soloveichik

Beilstein J. Nanotechnol. 2014, 5, 1399–1418, doi:10.3762/bjnano.5.153

Influence of the PDMS substrate stiffness on the adhesion of Acanthamoeba castellanii

• Sören B. Gutekunst,
• Carsten Grabosch,
• Alexander Kovalev,
• Stanislav N. Gorb and
• Christine Selhuber-Unkel

Beilstein J. Nanotechnol. 2014, 5, 1393–1398, doi:10.3762/bjnano.5.152

• . For all substrates, elastic moduli were determined from the unloading part of the curve to consider only the elastic behavior and not the plastic deformation of the sample. The measurements were performed under ambient conditions (25–26 °C temperature and 40–50% relative humidity). Analysis of the

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

• order of ΔV/LD ≈ 90 μm, where L ≈ 8 cm is the stroke length and D ≈ 0.8 cm the width of the (nominal) Hertzian contact region. A uniform water film of thickness Δd = 90 μm evaporates in about 500 s at room temperature, 50% relative humidity, and an evaporation rate of ≈ 1.7 × 10−7 m/s (see below). This

• ) temperature, pa is the water vapor pressure in the air (which is the product of the relative humidity and the saturation water pressure at the air temperature and air pressure), and v the velocity of the air (some distance from the water surface) over the water surface. Y is the latent heat of evaporation

• relative humidity of 50% giving pa = 0.5 × 2.3 kPa = 1.15 kPa. Hence, since v << 1 m/s, we get ≈ 1.7 × 10−7 m/s. Thus it takes Δt = Δd/ ≈ 60 s for the water film thickness to decrease by Δd ≈ 10 μm, which according to the theory is the film thickness range over which the capillary attraction between the