Nematic liquid crystal alignment on subwavelength metal gratings

• Irina V. Kasyanova,
• Artur R. Geivandov,
• Vladimir V. Artemov,
• Maxim V. Gorkunov and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2018, 9, 42–47, doi:10.3762/bjnano.9.6

• , Russia 10.3762/bjnano.9.6 Abstract We have studied the alignment of a nematic liquid crystal (LC) material on aluminum subwavelength nanogratings as a function of the period, p, and the slit width to period ratio, w/p. A method, based on Fourier analysis of the transmittance spectra of the LC grating

• values of the LC extraordinary refractive index. This information allows us to determine the average alignment of the LC molecules on the nanograting surface. Experimental We have fabricated aluminum films of ≈100 nm thickness on a glass substrate using the vacuum sputtering technique. The subwavelength

• slits. Since every grating contains 100 slits, and its size depends on the period, the reference squares of a size corresponding to each period were also milled. These squares, which are free of Al, were used as the reference areas in the optical spectra measurements. The glass plate with the aluminum

Localized growth of carbon nanotubes via lithographic fabrication of metallic deposits

• Fan Tu,
• Martin Drost,
• Imre Szenti,
• Janos Kiss,
• Zoltan Kónya and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2017, 8, 2592–2605, doi:10.3762/bjnano.8.260

• CNTs. In addition, Si signals were detected at both position 1 and 2, probably originating from the underlying substrate. At position 3, a large Si signal was detected along with minor carbon and aluminum signals. While the carbon signal might be derived from corresponding surface contamination, the

• origin of the aluminum signal is certainly the Al2O3 layer. In addition, we were not able to detect the Fe signal at this point. This is especially remarkable at position 2 in Figure 7b, however, this can be explained considering that EDX is not a surface sensitive method. Therefore the composition of

Synthesis of metal-fluoride nanoparticles supported on thermally reduced graphite oxide

• Alexa Schmitz,
• Kai Schütte,
• Vesko Ilievski,
• Juri Barthel,
• Laura Burk,
• Rolf Mülhaupt,
• Junpei Yue,
• Bernd Smarsly and
• Christoph Janiak

Beilstein J. Nanotechnol. 2017, 8, 2474–2483, doi:10.3762/bjnano.8.247

• slurry composed of 75 wt % FeF2-TRGO, 15 wt % active carbon and 10 wt % PVDF in NMP on an aluminum foil. A half-cell was assembled in Ar-filled glovebox with lithium foil as counter electrode and 1 M LiFeF6 in ethylene carbonate/ethylmethyl carbonate (50:50) as electrolyte. The galvanostatic charge

Laser-assisted fabrication of gold nanoparticle-composed structures embedded in borosilicate glass

• Nikolay Nedyalkov,
• Mihaela Koleva,
• Nadya Stankova,
• Rosen Nikov,
• Mitsuhiro Terakawa,
• Yasutaka Nakajima,
• Lyubomir Aleksandrov and
• Reni Iordanova

Beilstein J. Nanotechnol. 2017, 8, 2454–2463, doi:10.3762/bjnano.8.244

• ., silicate, phosphate and borate glasses, titanium and aluminum oxides, and polymers) are processed by laser radiation with appropriate parameters. Metal nanoparticles are formed within the irradiated area after a subsequent thermal annealing. This photoreduction process has been achieved by using CW lasers

Fabrication of gold-coated PDMS surfaces with arrayed triangular micro/nanopyramids for use as SERS substrates

• Jingran Zhang,
• Yongda Yan,
• Peng Miao and
• Jianxiong Cai

Beilstein J. Nanotechnol. 2017, 8, 2271–2282, doi:10.3762/bjnano.8.227

• approaches. They produced arrays of tipless pyramids using an optical UV curing method. Lee et al. [24] used anodic aluminum oxide as a template for transferring patterns onto the polydimethylsiloxane (PDMS) substrate surfaces using a dry etching method. In this work, the detection of DNA molecules showed a

A comparative study of the nanoscale and macroscale tribological attributes of alumina and stainless steel surfaces immersed in aqueous suspensions of positively or negatively charged nanodiamonds

• Colin K. Curtis,
• Antonin Marek,
• Alex I. Smirnov and
• Jacqueline Krim

Beilstein J. Nanotechnol. 2017, 8, 2045–2059, doi:10.3762/bjnano.8.205

• specifically designed for operating with one surface immersed in a liquid at a fundamental transverse shear mode. The aluminum QCM samples were anodized using a literature method that grows an alumina layer at the rate of 2 μm/h [30]. For these results, the liquid side QCM electrode was connected as the anode

• aluminum, the surface-exposed aluminum metal is readily oxidized to Al2O3 under ambient air. This surface layer of alumina is protecting the rest of metal from a further corrosion. In our experiments, the electrodes were additionally anodized for 3 min. This procedure is expected to yield approximately 50

• –100 nm thick Al2O3 layer. For Al2O3 is exposed to water one expect a formation of several aluminum hydroxide phases [49]. The presence of hydroxy (OH) groups on the alumina surface is affected by the oxide surface structure as well as other parameters with pH being the most important. Overall, the

Imidazolium-based ionic liquids used as additives in the nanolubrication of silicon surfaces

• Patrícia M. Amorim,
• Ana M. Ferraria,
• Rogério Colaço,
• Luís C. Branco and
• Benilde Saramago

Beilstein J. Nanotechnol. 2017, 8, 1961–1971, doi:10.3762/bjnano.8.197

• of ceramics. Other investigators followed this idea and added imidazolium-based ILs to base oils to lubricate steel/aluminum contacts [5][6][7] and steel/steel contacts [8][9][10][11][12][13]. Jiménez and Bermúdez [7] tested two ILs with the short alkyl chain imidazolium cation [EMIM], and the anions

Synthesis and catalytic application of magnetic Co–Cu nanowires

• Lijuan Sun,
• Xiaoyu Li,
• Zhiqiang Xu,
• Kenan Xie and
• Li Liao

Beilstein J. Nanotechnol. 2017, 8, 1769–1773, doi:10.3762/bjnano.8.178

• mainly electrodeposition by different templates, as found in the previous literature. For example, many papers have reported Co–Cu nanowires electrodeposited into a porous anodic aluminum oxide template [1][2][3][4]. Additionally, L. Gravier et al. [8] prepared Co–Cu multilayered nanowires by

Laser processing of thin-film multilayer structures: comparison between a 3D thermal model and experimental results

• Babak B. Naghshine and
• Amirkianoosh Kiani

Beilstein J. Nanotechnol. 2017, 8, 1749–1759, doi:10.3762/bjnano.8.176

• . Laser processing of Al-Si thin-film substrate The melting and boiling points of aluminum are 660 °C and 2470 °C respectively and aluminum has a latent heat of fusion of 397 kJ/kg and a latent heat of vaporization of 10,800 kJ/kg [22]. The measured and calculated ablation depths are presented in Table 2

• . The surface profiles at different frequencies and 5 W are shown in Figure 4. By applying a thin aluminum film to the surface, the ablation depth was significantly increased at 75 kHz compared to bare silicon samples. This can be explained by the smaller latent heat of vaporization and lower boiling

• temperature of aluminum, which means more material can be ablated using the same amount of energy. This can be further verified by the deeper holes at 25 and 50 kHz. The other reason is the lower plasma absorption of aluminum compared to silicon based on the calculated plasma absorption functions. Since the

Near-infrared-responsive, superparamagnetic Au@Co nanochains

• Varadee Vittur,
• Arati G. Kolhatkar,
• Shreya Shah,
• Irene Rusakova,
• Dmitri Litvinov and
• T. Randall Lee

Beilstein J. Nanotechnol. 2017, 8, 1680–1687, doi:10.3762/bjnano.8.168

• ). The mixture changed from yellow to colorless after the reaction had proceeded for an additional 30 min. The K–gold solution was stored under refrigeration in the dark for two days (with help of aluminum foil) until use. Synthesis of the Au@Co nanochains The synthesis of the nanochains proceeded using

Miniemulsion copolymerization of (meth)acrylates in the presence of functionalized multiwalled carbon nanotubes for reinforced coating applications

• Bertha T. Pérez-Martínez,
• Lorena Farías-Cepeda,
• Víctor M. Ovando-Medina,
• José M. Asua,
• Lucero Rosales-Marines and
• Radmila Tomovska

Beilstein J. Nanotechnol. 2017, 8, 1328–1337, doi:10.3762/bjnano.8.134

• microscopy (SEM) images were taken in a Hitachi S-4800. Differential scanning calorimetry (DSC) measurements of films cast from hybrid latexes and blends were carried out in a Q1000, TA Instruments apparatus. 5 mg of each sample were placed in standard aluminum DSC pans and analyzed in air atmosphere at a

Oxidative chemical vapor deposition of polyaniline thin films

• Yuriy Y. Smolin,
• Masoud Soroush and
• Kenneth K. S. Lau

Beilstein J. Nanotechnol. 2017, 8, 1266–1276, doi:10.3762/bjnano.8.128

• aluminum oxide, mesoporous TiO2, and activated carbon; these oCVD PTh coatings resulted in enhanced charge storage due to preservation of the surface area and pore space within the nanostructures [32]. As a result, PTh-coated carbon electrodes showed a 50% increase in specific capacitance and excellent

Nanotopographical control of surfaces using chemical vapor deposition processes

• Meike Koenig and
• Joerg Lahann

Beilstein J. Nanotechnol. 2017, 8, 1250–1256, doi:10.3762/bjnano.8.126

• and Oh used anodic aluminum oxide membranes as a template for the production of nanotubes with a tunable wall thickness (Figure 1) [11]. Via chemical oxidation polymerization of vaporized pyrroles, polypyrrole was deposited on the walls of the membrane pores which had been pretreated with ferric

• results in the deactivation of the reactive monomer species on the surface. Patterning was realized by placing conducting aluminum metal channels on a nonconductive glass surface [24]. The selective growth of various polymers was also found for surfaces equipped with different functional groups. This

• and patterned coatings from a great variety of polymer materials can be created that can be tailored to the respective applications. Polymer structures via masked deposition: polypyrrole nanotubes by deposition using aluminum oxide membranes with a pore size of 100 nm as the template. The wall

Hierarchically structured nanoporous carbon tubes for high pressure carbon dioxide adsorption

• Julia Patzsch,
• Deepu J. Babu and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2017, 8, 1135–1144, doi:10.3762/bjnano.8.115

• using an aluminum sample holder. High-resolution transmission microscopy (HRTEM) analysis was performed on lacey carbon copper grids (300 mesh) at a G2F20 (Tecnai) at the ERC-Jülich in Germany. IR measurements were performed on a Nicolet 6700 spectrometer with an ATR Smart Performer unit from Thermo

The integration of graphene into microelectronic devices

• Guenther Ruhl,
• Sebastian Wittmann,
• Matthias Koenig and
• Daniel Neumaier

Beilstein J. Nanotechnol. 2017, 8, 1056–1064, doi:10.3762/bjnano.8.107

• yields excellent results [4], but this is not a production-relevant approach. A material that is available in mass-production quantities and fulfills both mentioned requirements is aluminum oxide deposited by atomic-layer deposition (ALD). It was demonstrated that graphene encapsulated in Al2O3 could be

Needs and challenges for assessing the environmental impacts of engineered nanomaterials (ENMs)

• Michelle Romero-Franco,
• Hilary A. Godwin,
• Muhammad Bilal and
• Yoram Cohen

Beilstein J. Nanotechnol. 2017, 8, 989–1014, doi:10.3762/bjnano.8.101

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

• and anodic aluminum oxide template (AAO) with pore sizes of 200 nm were used as substrates and were coated simultaneously. Glass slides were used for electrical conductivity measurements and UV–visible spectroscopy (UV–vis). Si wafers were used for Fourier-transform infrared (FTIR) spectrophotometry

Recombinant DNA technology and click chemistry: a powerful combination for generating a hybrid elastin-like-statherin hydrogel to control calcium phosphate mineralization

• Mohamed Hamed Misbah,
• Mercedes Santos,
• Luis Quintanilla,
• Christina Günter,
• Matilde Alonso,
• Andreas Taubert and
• José Carlos Rodríguez-Cabello

Beilstein J. Nanotechnol. 2017, 8, 772–783, doi:10.3762/bjnano.8.80

• aluminum oxide crucible and heated at 20 °C/min under N2 purge (40 mL/min) from 50 to 1000 °C followed by an isothermal step at 1000 °C for 10 min. 6.6 Scanning electron microscopy (SEM) SEM images of the dry ELR/calcium phosphate composites were obtained using an FEI Quanta Field Emission SEM. Samples

First examples of organosilica-based ionogels: synthesis and electrochemical behavior

• Andreas Taubert,
• Ruben Löbbicke,
• Barbara Kirchner and
• Fabrice Leroux

Beilstein J. Nanotechnol. 2017, 8, 736–751, doi:10.3762/bjnano.8.77

• Netzsch DSC 204. DSC traces were recorded from −150 to 200 °C using liquid nitrogen cooling and a heating rate of 10 °C/min. Isothermal times were 5 min. Samples of ca. 5 mg were placed in aluminum pans with pierced lids. To remove traces of water the samples were heated to 120 °C before the first cooling

Vapor deposition routes to conformal polymer thin films

• Priya Moni,
• Ahmed Al-Obeidi and
• Karen K. Gleason

Beilstein J. Nanotechnol. 2017, 8, 723–735, doi:10.3762/bjnano.8.76

• in Figure 9c [43]. These coated nanotube forests were later shown to be beneficial to flexographic printing by Hart et al. [47]. Brown et al. showed that MLD could create 10 nm, conformal aluminum alkoxide derivative films on CNT sheets, as seen in Figure 9d, to create a composite material with 4

Liquid permeation and chemical stability of anodic alumina membranes

• Dmitrii I. Petukhov,
• Dmitrii A. Buldakov,
• Alexey A. Tishkin,
• Alexey V. Lukashin and
• Andrei A. Eliseev

Beilstein J. Nanotechnol. 2017, 8, 561–570, doi:10.3762/bjnano.8.60

• channels blocking. This process intensifies in basic pH due to the high positive charge of the anodic alumina surface. An approach for improving anodic aluminum oxide stability towards dissolution in water by carbon CVD coating of the membrane walls is suggested. Keywords: anodic alumina; carbon-modified

• membranes; membrane stability; microfiltration membranes; ultrafiltration membranes; Introduction Porous anodic aluminum oxide (AAO), developed as a protective coating, has received close attention of the membrane community due to its unusual porous structure represented by piercing cylindrical channels

• deionized water was used in experiments, we suggested that the degradation of the membrane occurred by dissolution of the anodic aluminum oxide and its further redeposition on the pore walls. For a detailed determination of the anodic alumina degradation mechanism, chemical dissolution and buffered solution

Diffusion and surface alloying of gradient nanostructured metals

• Zhenbo Wang and
• Ke Lu

Beilstein J. Nanotechnol. 2017, 8, 547–560, doi:10.3762/bjnano.8.59

• aluminization process at 560 °C and a subsequent diffusion annealing treatment at 720 °C was developed for the P92 ferritic–martensitic (F-M) steel with a preformed GNS surface layer [90]. A lower aluminum content aluminide (AlFe and α-(FeAl)) surface layer of ≈17 μm in thickness was produced on the F-M steel

Advances in the fabrication of graphene transistors on flexible substrates

• Gabriele Fisichella,
• Stella Lo Verso,
• Silvestra Di Marco,
• Vincenzo Vinciguerra,
• Emanuela Schilirò,
• Salvatore Di Franco,
• Raffaella Lo Nigro,
• Fabrizio Roccaforte,
• Amaia Zurutuza,
• Alba Centeno,
• Sebastiano Ravesi and
• Filippo Giannazzo

Beilstein J. Nanotechnol. 2017, 8, 467–474, doi:10.3762/bjnano.8.50

• method is allowed only for the LT process if a standard resist for lift-off process is considered [19]. The 250 °C used in the ST process would totally degrade the resist. Both LT and ST processes were repeated on an aluminum-coated silicon wafer, where a number of cycles was needed to produce a ≈30 nm

• degradation during the integration of the protective barrier. Figure 2d reports the schematic representation of the PEN substrate after the Al2O3 barrier integration. 200 nm thick aluminum back gate pads have been fabricated by metal sputtering, considering the same metal deposition process previously

• of the PEN-coated surface by a 100 nm protective Al2O3 layer and d) a schematic representation of the Al2O3 barrier/PEN substrate. a) Tapping mode atomic force microscopy (tAFM) morphology and b) schematic illustration of the aluminum back-gate pad. c) tAFM morphology and d) related schematic

Functionalized TiO₂ nanoparticles by single-step hydrothermal synthesis: the role of the silane coupling agents

• Antoine R. M. Dalod,
• Lars Henriksen,
• Tor Grande and
• Mari-Ann Einarsrud

Beilstein J. Nanotechnol. 2017, 8, 304–312, doi:10.3762/bjnano.8.33

• water obtained after the centrifugation steps was placed on an aluminum sample holder which was set to dry overnight. The line-intercept method was used to calculate average particle sizes, using sample pictures containing more than 300 intercepts. Transmission electron microscopy (TEM) images were

Surface-enhanced Raman scattering of self-assembled thiol monolayers and supported lipid membranes on thin anodic porous alumina

• Marco Salerno,
• Amirreza Shayganpour,
• Barbara Salis and
• Silvia Dante

Beilstein J. Nanotechnol. 2017, 8, 74–81, doi:10.3762/bjnano.8.8

• anodic porous alumina (tAPA) was fabricated from a 500 nm thick aluminum (Al) layer coated on silicon wafers, through single-step anodization performed in a Teflon electrochemical cell in 0.4 M aqueous phosphoric acid at 110 V. Post-fabrication etching in the same acid allowed obtaining tAPA surfaces

• ; SERS; nanopores; supported lipid bilayers; thiols; Introduction Anodic porous alumina (APA) is a layered material usually obtained in thick form (≈10 µm thickness scale) from electrochemical anodization in the acidic aqueous electrolyte of aluminum (Al) foils [1]. In APA, the control of pore size