Synthesis of coaxial nanotubes of polyaniline and poly(hydroxyethyl methacrylate) by oxidative/initiated chemical vapor deposition

• Alper Balkan,
• Efe Armagan and
• Gozde Ozaydin Ince

Beilstein J. Nanotechnol. 2017, 8, 872–882, doi:10.3762/bjnano.8.89

• PANI nanotubes, the resistance changed parabolically with relative humidity because of competing effects of doping and swelling of the PANI polymer under humid conditions. Introducing a hydrogel inner layer increased the overall resistance, and enhanced swelling, which caused the resistance to

• continuously increase with relative humidity. Keywords: coaxial nanotubes; humidity sensors; initiated chemical vapor deposition; oxidative chemical vapor deposition; polyaniline; Introduction In recent years, with the advances in nanotechnology, the use of nanostructured materials has become widespread in

• the probes in the presence of gold electrodes. For PANI flat films, the actual resistance values (R) versus relative humidity (RH%) are plotted in Figure 7. The resistance slightly decreases as RH% increases up to a certain value (RH% of 84.3%). Above 84.3% resistance starts to increase with humidity

Measuring adhesion on rough surfaces using atomic force microscopy with a liquid probe

• Juan V. Escobar,
• Cristina Garza and
• Rolando Castillo

Beilstein J. Nanotechnol. 2017, 8, 813–825, doi:10.3762/bjnano.8.84

• al. [33] measured Fadh = 26.6 ± 0.4 nN in air at a relative humidity of (46 ± 3)% (kc = 0.11 ± 0.02 N/m) with a tip curvature radius of 30 ± 5 nm. Eastman et al. [34] measured Fadh = 51 nN with commercial tips and Lomboy et al. [28] measured 50.7 ± 0.7 nN in air with a tip curvature radius of 35 nm

Phospholipid arrays on porous polymer coatings generated by micro-contact spotting

• Sylwia Sekula-Neuner,
• Monica de Freitas,
• Lea-Marie Tröster,
• Tobias Jochum,
• Pavel A. Levkin,
• Michael Hirtz and
• Harald Fuchs

Beilstein J. Nanotechnol. 2017, 8, 715–722, doi:10.3762/bjnano.8.75

• ) support (HEMA). Spotting was performed at 55–65% relative humidity. All patterning procedures were carried out with the sample stage tilted by 8° with respect to the SPT tip to minimize the probability of a contact between the ink reservoir and the sample surface. For all patterns, except the ones used

Graphene functionalised by laser-ablated V₂O₅ for a highly sensitive NH₃ sensor

• Margus Kodu,
• Artjom Berholts,
• Tauno Kahro,
• Mati Kook,
• Peeter Ritslaid,
• Helina Seemen,
• Tea Avarmaa,
• Harry Alles and
• Raivo Jaaniso

Beilstein J. Nanotechnol. 2017, 8, 571–578, doi:10.3762/bjnano.8.61

• concentration of N2 and O2 gases was held constant during measurements. The gas flow through the sample chamber was kept constant at 200 sccm while the concentration of the test gas was regulated by the ratio of the flow rates of individual gas components. The nominal relative humidity of the testing gas was 20

Impact of air exposure and annealing on the chemical and electronic properties of the surface of SnO₂ nanolayers deposited by rheotaxial growth and vacuum oxidation

• Monika Kwoka and
• Maciej Krzywiecki

Beilstein J. Nanotechnol. 2017, 8, 514–521, doi:10.3762/bjnano.8.55

• 2 h. In order to improve their stoichiometry, an additional in situ vacuum oxidation was performed at a chosen optimal partial pressure of 10−2 mbar for the next 2 h (108 L). The samples were then examined by using XPS. At the next step the samples were exposed to dry air with a relative humidity of

Biological and biomimetic materials and surfaces

• Stanislav Gorb and
• Thomas Speck

Beilstein J. Nanotechnol. 2017, 8, 403–407, doi:10.3762/bjnano.8.42

• smooth vertical surfaces and ceilings. The functioning of the pads depends on various environmental factors. Heepe et al. showed that the attachment performance of the beetle Coccinella septempunctata depends on the relative humidity. The authors demonstrated that both low (15%) and high (99

Nanocrystalline TiO₂/SnO₂ heterostructures for gas sensing

• Barbara Lyson-Sypien,
• Anna Kusior,
• Mieczylaw Rekas,
• Jan Zukrowski,
• Marta Gajewska,
• Katarzyna Michalow-Mauke,
• Thomas Graule,
• Marta Radecka and
• Katarzyna Zakrzewska

Beilstein J. Nanotechnol. 2017, 8, 108–122, doi:10.3762/bjnano.8.12

• were carried out in dry atmosphere. The synthetic air contained less than 1 ppm of water vapor while that of hydrogen + argon mixture had less than 10 ppm of contaminants. The relative humidity level was verified to be of about 0–1% RH at room temperature. Dynamic changes in the electrical resistance

Nanostructured SnO₂–ZnO composite gas sensors for selective detection of carbon monoxide

• Paul Chesler,
• Cristian Hornoiu,
• Susana Mihaiu,
• Cristina Vladut,
• Jose Maria Calderon Moreno,
• Mihai Anastasescu,
• Carmen Moldovan,
• Bogdan Firtat,
• Costin Brasoveanu,
• George Muscalu,
• Ion Stan and
• Mariuca Gartner

Beilstein J. Nanotechnol. 2016, 7, 2045–2056, doi:10.3762/bjnano.7.195

• is an important factor which influences sensor response. In Figure 12 different sensors were tested in an atmosphere containing 62% relative humidity. It can be observed that the sensor having the highest response to CO (S2) is only slightly influenced by humidity at its optimum working temperature

• of CO at their corresponding working temperatures. S2 response (recorded in December 2015) to CO as a function of the working temperature. Different composite sensor responses to relative humidity (62%). Sensor cross-response (recorded in December 2015) to different concentrations of gases, at the

“Sticky invasion” – the physical properties of Plantago lanceolata L. seed mucilage

• Agnieszka Kreitschitz,
• Alexander Kovalev and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1918–1927, doi:10.3762/bjnano.7.183

• humidity were continuously recorded using a Tinytag TGP-4500 (Gemini Data Loggers Ltd, United Kingdom). The measured temperature was 22–23 °C, the relative humidity was 30–37%. Pull-off force measurements of the mucilage For the pull-off force measurements five sets of measurements were made on five

Surface-enhanced infrared absorption studies towards a new optical biosensor

• Lothar Leidner,
• Julia Stäb,
• Jennifer T. Adam and
• Günter Gauglitz

Beilstein J. Nanotechnol. 2016, 7, 1736–1742, doi:10.3762/bjnano.7.166

• PBS, there is a further increase of the absorption band. Equilibrium is reached 15 min after PBS is introduced. The experiment was performed under ambient conditions (room temperature, optical path through humid air, relative humidity was not recorded). Air humidity is responsible for the sharp peaks

Nanostructured TiO₂-based gas sensors with enhanced sensitivity to reducing gases

• Wojciech Maziarz,
• Anna Kusior and
• Anita Trenczek-Zajac

Beilstein J. Nanotechnol. 2016, 7, 1718–1726, doi:10.3762/bjnano.7.164

• an air flow ratio of 500 sccm, temperature of 146 °C, relative humidity of 55%, and a stabilization time of 3 h. The preheating temperature rate was ≈3.5 °C/min. Afterwards, two different types of tests were performed: (1) the measurement of sensor response at constant gas concentration under varying

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

• glass plate (18 × 18 × 0.4 cm3) with a small aluminum-made vessel, or alternately placed in a Teflon container with a glass vessel, containing 0.2 mL of organosilane (ODS or FAS17), in a dry N2 atmosphere at less than 5 % relative humidity. Another heat-resistant glass plate was then placed on top of it

• was then spin-coated (500 rpm for 5 s and 1000 rpm for 10 s) onto UV–ozone-cleaned Si substrates (5 × 5 cm2) at room temperature, under a relative humidity of (40 ± 5)%. All samples were dried in air at room temperature for more than 24 h. Details of our preparation methods for the monolayers and

• different surface chemical and physical properties, (see above)) were measured. Obtained force–time curves were used to estimate the maximal traction force. Experiments were performed at 23 °C temperature and 26–29% relative humidity. We tested 10 male and 10 females and carried out 160 traction tests in

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