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

• method [18] was used to calibrate the cantilevers and was performed directly before every measurement. In order to start every experiment under the same conditions, the first step was to reduce RH to the lowest possible value (around 5%). The cantilever was left in these conditions for several hours to

• equilibrate RH and the cantilever deflection to a stationary value. From this point, the adsorption curve followed by the desorption curve were recorded stepwise with 30–45 min equilibration time before reading out the cantilever deflection for each step. A cross section of the AFM cantilever after the

Case studies on the formation of chalcogenide self-assembled monolayers on surfaces and dissociative processes

• Yongfeng Tong,
• Tingming Jiang,
• Azzedine Bendounan,
• Makri Nimbegondi Kotresh Harish,
• Angelo Giglia,
• Stefan Kubsky,
• Fausto Sirotti,
• Luca Pasquali,
• Srinivasan Sampath and
• Vladimir A. Esaulov

Beilstein J. Nanotechnol. 2016, 7, 263–277, doi:10.3762/bjnano.7.24

• . Interestingly, on transition metals such as Rh, W and Ni, there are observations of multicomponent S 2p spectra [66][67][68], which could be due to some type of interface sulfide layers. Understanding the interfaces in these situations is thus very important. A good knowledge of monolayer atomic chalcogen

pH-Triggered release from surface-modified poly(lactic-co-glycolic acid) nanoparticles

• Manuel Häuser,
• Klaus Langer and
• Monika Schönhoff

Beilstein J. Nanotechnol. 2015, 6, 2504–2512, doi:10.3762/bjnano.6.260

• polymer than PDADMAC. Released amount of PDADMAC per surface area in dependence of the pH. The amount of released PDADMAC was related to the total particle surface to yield the released amount per surface area. Zeta potential (ζ) and hydrodynamic radii (RH) of PAA-coated PLGA-PEI nanoparticles in

Lower nanometer-scale size limit for the deformation of a metallic glass by shear transformations revealed by quantitative AFM indentation

• Arnaud Caron and
• Roland Bennewitz

Beilstein J. Nanotechnol. 2015, 6, 1721–1732, doi:10.3762/bjnano.6.176

• radiation and differential scanning calorimetry (DSC). We observed a broad diffraction peak at 39.866 degrees of 2θ, a clear glass transition at Tg = 223 °C, and crystallization at Tx = 295 °C using a heating rate RH = 0.67 K/s. The surface of an as-spun Pt-based metallic glass ribbon was prepared by

Structural and magnetic properties of iron nanowires and iron nanoparticles fabricated through a reduction reaction

• Marcin Krajewski,
• Wei Syuan Lin,
• Hong Ming Lin,
• Katarzyna Brzozka,
• Sabina Lewinska,
• Natalia Nedelko,
• Anna Slawska-Waniewska,
• Jolanta Borysiuk and
• Dariusz Wasik

Beilstein J. Nanotechnol. 2015, 6, 1652–1660, doi:10.3762/bjnano.6.167

• = 0.1542 nm) and a LYNXEYE detector and also a standard Mössbauer spectrometer (POLON) equipped with a 57Co/Rh source of γ-radiation placed on a vibrator, working in a constant acceleration mode. Magnetic properties were determined by means of an Oxford Instruments Ltd. vibrating sample magnetometer (VSM

Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials

• Xiaoxing Ke,
• Carla Bittencourt and
• Gustaaf Van Tendeloo

Beilstein J. Nanotechnol. 2015, 6, 1541–1557, doi:10.3762/bjnano.6.158

• ]. Systematic studies of different metals on CNTs has been reported, including Au, Pt, Pd, Rh, Cu and Ti [67][70][71][72][73][74][75]. Early studies using HRTEM have revealed that Au and Pt form mostly well-crystallized nanocrystal islands with limited contact areas with the CNTs walls, whereas Pd and Rh form

Pt- and Pd-decorated MWCNTs for vapour and gas detection at room temperature

• Hamdi Baccar,
• Atef Thamri,
• Pierrick Clément,
• Eduard Llobet and
• Adnane Abdelghani

Beilstein J. Nanotechnol. 2015, 6, 919–927, doi:10.3762/bjnano.6.95

• multiwalled carbon nanotubes decorated with Au, Pd or Ni nanoparticles (formed by evaporation of metals) and also with Rh or Pt nanoparticles (from a colloidal solution) for detecting benzene, nitrogen dioxide and hydrogen sulphide [34][35][36]. Although the detection could be performed at room temperature

• within the sensor chamber was 10% RH. Results and Discussion Morphological and compositional studies The morphology of the plasma-treated, metal-decorated, multiwalled carbon nanotubes was studied by TEM and the main results are summarised in Figure 1. It can be derived that the sputtering technique

• with bare oxygen-plasma-treated or Rh- and FeO-decorated MWCNTs, which were found to be responsive to aromatic VOCs [24][36][38]. Pd- and Pt-decorated MWCNT sensors were responsive to the non-aromatic VOCs tested. Typical response and recovery cycles toward non-aromatic VOCs are shown Figure 3 and

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

• Figure 1a. At ambient temperature and RH (RH ca. 40%) water accumulates at the flat terraces on the crystal surface forming rounded islands [40] (see Figure 1b and Experimental section) over a time scale of few minutes. Under our experimental conditions, the islands exhibited a typical thickness of 1–1.5

• the one shown in Figure 2b. A similar distance of 3.93 ± 0.40 nm from the jump-to-contact to the point of zero separation is found in the approach path of force curves collected in contact mode on CaF2 crystals with adsorbed water layers on top of the surface (see Figure 2c) at ca. 40% RH. Force

• of hydrated CaF2 and the expected thickness of the water layer on top of the tip (1 nm at room temperature, RH ca. 40% and in the absence of contamination) [46]. This distance indicates that water meniscus forms upon geometrical contact of the absorbed water layers on top of the tip and the crystal

Magnetic properties of self-organized Co dimer nanolines on Si/Ag(110)

• Lisa Michez,
• Kai Chen,
• Fabien Cheynis,
• Frédéric Leroy,
• Alain Ranguis,
• Haik Jamgotchian,
• Margrit Hanbücken and
• Laurence Masson

Beilstein J. Nanotechnol. 2015, 6, 777–784, doi:10.3762/bjnano.6.80

• ]. Although the shoulder at +4 eV from the L3 edge can be observed for other Co nanostructures (e.g., an ultrathin 1.25 ML Co film grown on Rh(111) [33] or a superlattice of 0.35 ML 2D Co nanoparticles on Au(788) [4]) this feature is more pronounced in the case of our Co nanolines, especially for low Co

Nanoparticle shapes by using Wulff constructions and first-principles calculations

• Georgios D. Barmparis,
• Zbigniew Lodziana,
• Nuria Lopez and
• Ioannis N. Remediakis

Beilstein J. Nanotechnol. 2015, 6, 361–368, doi:10.3762/bjnano.6.35

• ], Si in amorphous SiO2 [37], diamond in amorphous C [38], Rh and Pd under oxidizing conditions [39], Cu in N gas [40], Au under oxidizing conditions [41], noble metals with an environment [42], complex metal hydrides [43], iron carbides [44] and dawsonites [45][46], just to name a few. Atomistic Wulff

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

• 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

• common writing speed is 4 μm/s, RH is 30%. Kinetics of LAO-AFM on Si by using CNF versus Si probes. a) Line height upon writing speed for a bias voltage of 20 V. b) Line height upon bias voltage for a writing speed of 1 μm/s. Full width at half maximum (FWHM) of the same features upon writing speed (c

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

• 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

• for 2–92 year-old humans, and in [29] a range of 1.23–4.10 × 105 N/cm2 (RH = 30%) was given for 15–35 year-old humans. Thus, our results (3.04 × 105 N/cm2, RH = 50%, hairs from a 29 year-old human) are in good agreement with these literature values, indicating that CAT yields reliable results

Synthesis and characterization of fluorescence-labelled silica core-shell and noble metal-decorated ceria nanoparticles

• Rudolf Herrmann,
• Markus Rennhak and
• Armin Reller

Beilstein J. Nanotechnol. 2014, 5, 2413–2423, doi:10.3762/bjnano.5.251

• determination of the number of thiol groups and an estimate for the number of fluorescent molecules per nanoparticles, including a scattering correction, have been developed. Ceria nanoparticles decorated with noble metals (Pt, Pd, Rh) are models for the decomposition products of automobile catalytic converters

• which serve as models for the particles formed by mechanical decomposition of automobile catalytic converters. We succeeded in controlling the agglomeration of small (8–10 nm) ceria NP and obtaining almost monodisperse agglomerates (40–260 nm) which can be decorated with noble metal NP (Pt, Pd, Rh, 2–5

Inorganic Janus particles for biomedical applications

• Isabel Schick,
• Steffen Lorenz,
• Dominik Gehrig,
• Stefan Tenzer,
• Wiebke Storck,
• Karl Fischer,
• Dennis Strand,
• Frédéric Laquai and
• Wolfgang Tremel

Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244

• highly monodisperse with sizes of Rh(Au) = 6.5 nm, Rh(Au@Fe3O4) = 12.8 nm, and Rh(Au@Fe3O4@SiO2) = 19.5 nm. The progressive increase of the hydrodynamic radii is in good accordance with the increase in particle diameter. The thickness of the silica shell was determined by TEM, and matches the expected

The gut wall provides an effective barrier against nanoparticle uptake

• Heike Sinnecker,
• Thorsten Krause,
• Sabine Koelling,
• Ingmar Lautenschläger and
• Andreas Frey

Beilstein J. Nanotechnol. 2014, 5, 2092–2101, doi:10.3762/bjnano.5.218

• volume of 5 mL. An internal standard (rhodium, Rh) was added to every sample. The mass of europium 153Eu and internal standard 103Rh was measured with a PE-Elan DRC II ICP-MS, the amount of europium in the samples was derived from a standard curve, established with Eu standard solution (Bernd Kraft GmbH

Effects of surface functionalization on the adsorption of human serum albumin onto nanoparticles – a fluorescence correlation spectroscopy study

• Pauline Maffre,
• Stefan Brandholt,
• Karin Nienhaus,
• Li Shang,
• Wolfgang J. Parak and
• G. Ulrich Nienhaus

Beilstein J. Nanotechnol. 2014, 5, 2036–2047, doi:10.3762/bjnano.5.212

• hydrodynamic radius, RH, of the diffusing particle can be obtained. Sub-nanometer precision is achieved by performing extremely careful measurements and calibration procedures to account for the refractive index mismatch between the sample solution and the immersion medium, viscosity changes of the sample

• reliable in our hands. In our original FCS study [45], we investigated the adsorption of human serum albumin (HSA) onto carboxyl-functionalized, polymer-encased iron platinum nanoparticles (Fe–Pt NPs) with a hydrodynamic radius, RH, of 5–6 nm. We prepared HSA solutions of different concentrations in

• phosphate buffered saline (PBS), pH 7.4, and mixed these solutions, one after the other, with the NP solution (0.1–2 nM) to measure the hydrodynamic radius of the NPs as a function of protein concentration. With increasing HSA concentration, RH increased in a single step, indicating that the HSA molecules

Cathode lens spectromicroscopy: methodology and applications

• T. O. Menteş,
• G. Zamborlini,
• A. Sala and
• A. Locatelli

Beilstein J. Nanotechnol. 2014, 5, 1873–1886, doi:10.3762/bjnano.5.198

• almost 8 eV at a coverage of 0.5 eMLIr(100) [59]. We note, however, that Au binds strongly to other noble metal substrates. For instance, on Rh(110) the binding energy of Au is 3.5 eV at ML-coverage [60]. Due to the strong interaction with Ir, the adsorption of Au weakens the C–Ir bonds, and the high

Room temperature, ppb-level NO₂ gas sensing of multiple-networked ZnSe nanowire sensors under UV illumination

• Sunghoon Park,
• Soohyun Kim,
• Wan In Lee,
• Kyoung-Kook Kim and
• Chongmu Lee

Beilstein J. Nanotechnol. 2014, 5, 1836–1841, doi:10.3762/bjnano.5.194

• constant flow rate of 200 cm3/min at 25 °C under 50% RH. The NO2 concentration was controlled by mixing NO2 gas with synthetic air at different ratios. The detailed procedures for the sensor fabrication and sensing test are reported elsewhere [32]. The electrical resistance of the gas sensors was

The surface properties of nanoparticles determine the agglomeration state and the size of the particles under physiological conditions

• Christoph Bantz,
• Olga Koshkina,
• Thomas Lang,
• Hans-Joachim Galla,
• C. James Kirkpatrick,
• Roland H. Stauber and
• Michael Maskos

Beilstein J. Nanotechnol. 2014, 5, 1774–1786, doi:10.3762/bjnano.5.188

• over time and the analysis of the self-correlated data yields information about the hydrodynamic radius (Rh) of the sample. The fluctuations in scattering intensity initially originate from the Brownian motion of the particles [24][25]. For data analysis, these fluctuations are transferred to the

• polydispersity value of this sample. Furthermore, this example nicely illustrates that especially for polydisperse samples only the extrapolation q2 → 0 can yield true values for Ds (and similarly also for Rh). Multicomponent analysis [28] to evaluate the DLS measurement of the mixture of amorphous silica

• (organosiloxane) nanoparticles starting from AHAPS-modified particles. Hydrodynamic radius, Rh, and μ2 values in different media for the samples discussed in this publication. NexSil20 NPs are commercial silica nanoparticles, POS-NH2 NPs are amine-modified poly(organosiloxane) particles at different modification

Controlling the dispersion of supported polyoxometalate heterogeneous catalysts: impact of hybridization and the role of hydrophilicity–hydrophobicity balance and supramolecularity

• Gijo Raj,
• Colas Swalus,
• Eglantine Arendt,
• Pierre Eloy,
• Michel Devillers and
• Eric M. Gaigneaux

Beilstein J. Nanotechnol. 2014, 5, 1749–1759, doi:10.3762/bjnano.5.185

• . The DODA–POM hybrid films, after AFM imaging, were treated in an UV–ozone chamber (Jelight USA) for 10 min. Atomic force microscopy AFM experiments were performed by using a Nanoscope V multimode AFM (Bruker AXS) in tapping mode under ambient conditions (23 °C and 56% RH). Thin films of the POM, DODA

Effects of palladium on the optical and hydrogen sensing characteristics of Pd-doped ZnO nanoparticles

• Anh-Thu Thi Do,
• Hong Thai Giang,
• Thu Thi Do,
• Ngan Quang Pham and
• Giang Truong Ho

Beilstein J. Nanotechnol. 2014, 5, 1261–1267, doi:10.3762/bjnano.5.140

• relative humidity of 65% RH. To keep the operating temperature of the sensor in the range of 200–300 °C, an applied voltage Vapplied of 1.7 V and a current of about 120 mA are required. The obtained linear curve implied that it is possible to control the operating temperature by turning the applied voltage

• of 65% RH, the linear dependence of the sensitivity of the Pd/ZnO-based sensor on hydrogen concentrations in the range of 0–25% LEL was observed as shown in Figure 4b. The gas sensing mechanism usually accepted for semiconductor sensors explains the functionality due to reactions of hydrogen with the

• ) the specificity of the Pd/ZnO sample at 1 vol % of H2, CO and C3H8 with a humidity of 65% RH. Response characteristics of the hydrogen sensor based on Pd/ZnO nanoparticles. Stability over time of the investigated sensor as a function of (a) time and (b) in hydrogen atmosphere.

Nanoporous composites prepared by a combination of SBA-15 with Mg–Al mixed oxides. Water vapor sorption properties

• Amaury Pérez-Verdejo,
• Alvaro Sampieri,
• Heriberto Pfeiffer,
• Mayra Ruiz-Reyes,
• Juana-Deisy Santamaría and
• Geolar Fetter

Beilstein J. Nanotechnol. 2014, 5, 1226–1234, doi:10.3762/bjnano.5.136

• are homogeneously dispersed. Vapor sorption behavior The water vapor adsorption–desorption isotherms of all samples were acquired at 60 °C with a rate of 0.5%·min−1 of relative humidity (RH) until to achieve 80% of RH (Figure 5). The calcined hydrotalcite (HT) adsorbs up to 5.0 mmol H2O/gHT and the

• hydrotalcite. This extraordinary amount of adsorbed water can also be related to the high surface area of this composite, 806 m2/g. Moreover, a wider hysteresis, between 80% and 40% of RH%, is observed for this sample, (Mg/Al)/SBA, Figure 5, indicating that water is slowly desorbed. Such behavior can be

• behavior observed in the (Mg/Al)/SBA is manly, a capillary condensation in intra-wall micropores. Some experiments were carried out at different RH (20, 40, 60 or 80%) through a continuous increase of the temperature from 35 to 70 °C to determine the maximum capacity of the water vapor adsorption of the HT

Enhanced photocatalytic hydrogen evolution by combining water soluble graphene with cobalt salts

• Jing Wang,
• Ke Feng,
• Hui-Hui Zhang,
• Bin Chen,
• Zhi-Jun Li,
• Qing-Yuan Meng,
• Li-Ping Zhang,
• Chen-Ho Tung and
• Li-Zhu Wu

Beilstein J. Nanotechnol. 2014, 5, 1167–1174, doi:10.3762/bjnano.5.128

• ][27][28][29][30][31][32][33]. Specifically, graphene has been involved in photocatalytic hydrogen production systems [34], such as TiO2-(N)RGO-Pt [35][36][37][38], g-C3N4-RGO-Pt [39], CdS-RGO-Pt [40][41][42][43], MoS2-NRGO [44][45], EY-RGO-Pt [46] and BiVO4-RGO-Ru/SrTiO3:Rh [47] (RGO: reduced graphene

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

• conditions (temperature of 22 ± 1 °C, humidity of 45–55% RH). The voltage was applied as shown in Figure 11. For each applied voltage, at least three images at different areas were recorded to confirm the scanning itself did not result in the change of the nanobubbles. Besides DI water, three kinds of saline

Volcano plots in hydrogen electrocatalysis – uses and abuses

• Paola Quaino,
• Fernanda Juarez,
• Elizabeth Santos and
• Wolfgang Schmickler

Beilstein J. Nanotechnol. 2014, 5, 846–854, doi:10.3762/bjnano.5.96

• indicate the older values. None such measurements have been made for other metals of this group like Re and Rh, and the rates on these metals may well be higher than indicated. In any case, with the exception of Co and Ni, the rates are fast on these metals. They seem to be about one order of magnitude