Colorimetric detection of Cu²⁺ based on the formation of peptide–copper complexes on silver nanoparticle surfaces

• Gajanan Sampatrao Ghodake,
• Surendra Krishna Shinde,
• Rijuta Ganesh Saratale,
• Avinash Ashok Kadam,
• Ganesh Dattatraya Saratale,
• Asad Syed,
• Fuad Ameen and
• Dae-Young Kim

Beilstein J. Nanotechnol. 2018, 9, 1414–1422, doi:10.3762/bjnano.9.134

• , some aggregates appeared, whereas, the average size of the individual AgNPs remained unchanged (Figure 1c). Accordingly, we concluded that under centrifugation conditions, bilayer structures of casein peptides remain intact and stable, thereby inhibiting AgNP aggregation and enabling increased

Computational exploration of two-dimensional silicon diarsenide and germanium arsenide for photovoltaic applications

• Sri Kasi Matta,
• Chunmei Zhang,
• Yalong Jiao,
• Anthony O'Mullane and
• Aijun Du

Beilstein J. Nanotechnol. 2018, 9, 1247–1253, doi:10.3762/bjnano.9.116

• and Pb [20][35] and are depicted in Figure 2c. According to this evaluation, the exfoliation of monolayer for these materials from their bulk forms is highly feasible. The band structures determined by HSE-Wannier calculations demonstrate that bulk, bilayer and monolayer structures of SiAs2 and GeAs2

• Fermi level is set as zero. (a–c) Bulk, bilayer and monolayer of SiAs2, respectively; (d–f) bulk, bilayer and monolayer of GeAs2, respectively. Calculated light absorption spectrum of monolayers of SiAs2 (green) and GeAs2 (blue) using HSE functional superimposed to the incident AM1.5G solar flux. (a,c

Circular dichroism of chiral Majorana states

• Javier Osca and
• Llorenç Serra

Beilstein J. Nanotechnol. 2018, 9, 1194–1199, doi:10.3762/bjnano.9.110

• (λ) is modeling a coupled bilayer system in which quasiparticles move. The set of Hamiltonian parameters is m0, m1, ΔB, μ, α, Δp and Δm. The latter two are given in terms of the pairing interaction in the two layers, Δt and Δb, by Hybridization of the two surfaces is represented by parameters m0 and

Field-controlled ultrafast magnetization dynamics in two-dimensional nanoscale ferromagnetic antidot arrays

• Anulekha De,
• Sucheta Mondal,
• Sourav Sahoo,
• Saswati Barman,
• Yoshichika Otani,
• Rajib Kumar Mitra and
• Anjan Barman

Beilstein J. Nanotechnol. 2018, 9, 1123–1134, doi:10.3762/bjnano.9.104

• irradiation of laser light. A PMMA/MMA bilayer resist was used for electron-beam lithography to prepare the resist pattern on the Py thin film followed by argon ion milling at a base pressure of 1 × 10−4 Torr with a beam current of 60 mA for 6 min for etching out the Py film from everywhere except the

An implementation of spin–orbit coupling for band structure calculations with Gaussian basis sets: Two-dimensional topological crystals of Sb and Bi

• Sahar Pakdel,
• Mahdi Pourfath and
• J. J. Palacios

Beilstein J. Nanotechnol. 2018, 9, 1015–1023, doi:10.3762/bjnano.9.94

• divided into two categories. The most recent publications refer to monolayer antimonene (or occasionally bilayer antimonene) and can be found in the context of new 2D crystals. Other works, which go a few years back in time, refer to few-layered (FL) antimonene (or Sb(111) thin films), and can be found in

The effect of atmospheric doping on pressure-dependent Raman scattering in supported graphene

• Egor A. Kolesov,
• Mikhail S. Tivanov,
• Olga V. Korolik,
• Olesya O. Kapitanova,
• Xiao Fu,
• Hak Dong Cho,
• Tae Won Kang and
• Gennady N Panin

Beilstein J. Nanotechnol. 2018, 9, 704–710, doi:10.3762/bjnano.9.65

• . Results and Discussion Pressure-dependent Raman measurements Raman spectra of graphene on various substrates under atmospheric pressure are presented in Figure 1. Monolayer and bilayer graphene were identified by 2D peak approximations with one and four Lorentz functions, respectively, together with the

• 2D peak full-width at half-maximums (FWHMs). The I2D/IG intensity ratio shows values of up to 1.5 for the monolayer and about 0.9 for bilayer graphene (the low I2D/IG values can be explained by adsorption doping [9] and electrostatic doping effects [16], as analyzed throughout the article). Comparing

• results in renormalization of the Fermi velocity, Dirac point velocity, and overall distortion of the Dirac cone [24], leading to a possible charge carrier density increase [25]. In the case of bilayer graphene, the desorption process leads to a density decrease of about 0.4 × 1013 cm−2 hole, which is

Tuning adhesion forces between functionalized gold colloidal nanoparticles and silicon AFM tips: role of ligands and capillary forces

• Sven Oras,
• Sergei Vlassov,
• Marta Berholts,
• Rünno Lõhmus and
• Karine Mougin

Beilstein J. Nanotechnol. 2018, 9, 660–670, doi:10.3762/bjnano.9.61

• interactions represent a major part of the molecular forces acting between both contact surfaces, however, the presence of water vapor (humidity rate of the order of 35%) in air, has a strong impact on these results via capillary forces. In ambient conditions a water mono-bilayer with thickness around 1 nm can

Facile phase transfer of gold nanorods and nanospheres stabilized with block copolymers

• Yaroslav I. Derikov,
• Georgiy A. Shandryuk,
• Raisa V. Talroze,
• Alexander A. Ezhov and
• Yaroslav V. Kudryavtsev

Beilstein J. Nanotechnol. 2018, 9, 616–627, doi:10.3762/bjnano.9.58

• nanorods depend on the refractive index of a medium bordering the nanorod surface. The effect is more pronounced for the TM mode. As shown in [47], in hydrosols, CTAB forms a 4–5 nm bilayer at the surface of Au nanoparticles. The optical dispersion curves for the substances relevant to this study are

• 436 nm [51]. Thus, the presence of a CTAB bilayer at the Au nanorod surface should noticeably shift the maximum position of the TM plasmon resonance in water and benzene. This can be checked by simulations for a model in which a single nanorod is coated with a surface layer with the refractive index

• maximum is situated between the peaks of two model spectra, we can conclude that some CTAB is present at the nanorod surface but its quantity is not enough to form a uniform bilayer. Presumably, the bilayer is rarefied near the nanorod ends. In nonpolar organosols, CTAB should form a ca. 2 nm monolayer at

Single-step process to improve the mechanical properties of carbon nanotube yarn

• Maria Cecilia Evora,
• Xinyi Lu,
• Nitilaksha Hiremath,
• Nam-Goo Kang,
• Kunlun Hong,
• Roberto Uribe,
• Gajanan Bhat and
• Jimmy Mays

Beilstein J. Nanotechnol. 2018, 9, 545–554, doi:10.3762/bjnano.9.52

• AA and AN. Another peak that has a significant intensity in graphene structures is the G′ band. The G′ band is a single peak in single-layer graphene, whereas it splits into four peaks in bilayer graphene, reflecting the evolution of the electron band structure [37][38]. However, the G′ band is not

Wafer-scale bioactive substrate patterning by chemical lift-off lithography

• Chong-You Chen,
• Chang-Ming Wang,
• Hsiang-Hua Li,
• Hong-Hseng Chan and
• Wei-Ssu Liao

Beilstein J. Nanotechnol. 2018, 9, 311–320, doi:10.3762/bjnano.9.31

• reproduction, and high resolution control. Conventional strategies to fabricate bioactive substrates rely on the creation of different local molecular environments that are suitable for subsequent biological species attachment. For example, the supported lipid bilayer system has been widely used for many

Dielectric properties of a bisimidazolium salt with dodecyl sulfate anion doped with carbon nanotubes

• Doina Manaila Maximean,
• Viorel Cîrcu and
• Constantin Paul Ganea

Beilstein J. Nanotechnol. 2018, 9, 164–174, doi:10.3762/bjnano.9.19

• in the LF domain (0.01 to 107 Hz), equipped with WinDETA software. The temperature was controlled within 0.2 K, at a constant ac voltage of 0.5 V. Schematic representation of the bilayer interdigitated SmA phase of the ILC based on bisimidazolium salts with alkyl sulfate ion. POM pictures of

Beyond Moore’s technologies: operation principles of a superconductor alternative

• Igor I. Soloviev,
• Nikolay V. Klenov,
• Sergey V. Bakurskiy,
• Mikhail Yu. Kupriyanov,
• Alexander L. Gudkov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2017, 8, 2689–2710, doi:10.3762/bjnano.8.269

Refractive index sensing and surface-enhanced Raman spectroscopy using silver–gold layered bimetallic plasmonic crystals

• Somi Kang,
• Sean E. Lehman,
• Matthew V. Schulmerich,
• An-Phong Le,
• Tae-woo Lee,
• Stephen K. Gray,
• Rohit Bhargava and
• Ralph G. Nuzzo

Beilstein J. Nanotechnol. 2017, 8, 2492–2503, doi:10.3762/bjnano.8.249

• material. Here we examine a bilayer/multi-metallic Ag/Au plasmonic crystal (PC) motif that is characterized by higher analytical sensitivity and more strongly enhanced electric fields than our previously reported monometallic PC systems. Manipulating the composition of the thin metal films, their spatial

• (45,000 Δ%T·nm/RIU) is nearly ≈1.41 times that of the Au thin film PC (32,000 Δ%T·nm/RIU). Higher mass-fractions of Ag in the bilayer stack progressively weaken the plasmonic response, as seen in the lower values of the FOM. Transmission spectra measured in water provide an important qualitative insight

• observed here in this work. Conclusion The influence of the mass coverage of Ag and Au thin films as well as the geometrical parameters of the nanohole arrays of bimetallic (bilayer) plasmonic crystals were characterized through multispectral bulk RI sensing and SERS measurements combined with insights

Expanding the molecular-ruler process through vapor deposition of hexadecanethiol

• Alexandra M. Patron,
• Timothy S. Hooker,
• Daniel F. Santavicca,
• Corey P. Causey and
• Thomas J. Mullen

Beilstein J. Nanotechnol. 2017, 8, 2339–2344, doi:10.3762/bjnano.8.233

• enables direct comparison of thickness to MHDA molecules. Figures 2A and 2B show representative 2 µm × 2 µm and 500 nm × 500 nm atomic force microscopy (AFM) images of a Cu-ligated MHDA-C16 bilayer formed from the solution deposition of MHDA for 18 h, Cu(ClO4)2·6H2O for 5 min, and C16 for 1 h. Figure 2C

• images of a Cu-ligated MHDA-C16 bilayer formed from the solution deposition of MHDA for 18 h and Cu(ClO4)2·6H2O for 5 min followed by vapor deposition of C16 for 1 h at 80 °C. Figure 3C displays a representative cursor profile across several islands as indicated by the red line in Figure 3B. The apparent

• height of these protruding islands (3.6 ± 0.2 nm) is consistent with the least-protruding C16 islands of the Cu-ligated MHDA-C16 bilayers formed via solution deposition. Protruding islands of greater thicknesses are not observed. The surface morphology of the Cu-ligated MHDA-C16 bilayer formed via vapor

Evaluating the toxicity of TiO₂-based nanoparticles to Chinese hamster ovary cells and Escherichia coli: a complementary experimental and computational approach

• Alicja Mikolajczyk,
• Natalia Sizochenko,
• Ewa Mulkiewicz,
• Anna Malankowska,
• Michal Nischk,
• Przemyslaw Jurczak,
• Seishiro Hirano,
• Grzegorz Nowaczyk,
• Adriana Zaleska-Medynska,
• Jerzy Leszczynski,
• Agnieszka Gajewicz and
• Tomasz Puzyn

Beilstein J. Nanotechnol. 2017, 8, 2171–2180, doi:10.3762/bjnano.8.216

• (Fe/N-co-doped) TiO2 nanocomposite particles were detectably cytotoxic [22]. More complex nanostructures of TiO2 bilayer nanosheets doped with bismuth tungstate (Bi2WO6) nanoclusters demonstrated enhanced antimicrobial activity towards E. coli: the bacteria population continuously decreased with the

Ta₂N₃ nanocrystals grown in Al₂O₃ thin layers

• Krešimir Salamon,
• Maja Buljan,
• Iva Šarić,
• Mladen Petravić and
• Sigrid Bernstorff

Beilstein J. Nanotechnol. 2017, 8, 2162–2170, doi:10.3762/bjnano.8.215

• of Ta within this sample, we examine the in-depth XPS spectra for different Ar+ sputtering times. The results are shown in Figure 6, displaying the change of the fraction of Ta–N and Ta–O bonds with depth over one bilayer. Again, the periodic variation of the Ta–N concentration is consistent with the

Intercalation of Si between MoS₂ layers

• Rik van Bremen,
• Qirong Yao,
• Soumya Banerjee,
• Deniz Cakir,
• Nuri Oncel and
• Harold J. W. Zandvliet

Beilstein J. Nanotechnol. 2017, 8, 1952–1960, doi:10.3762/bjnano.8.196

• structure of the MoS2–silicene–MoS2 hetero-trilayer. The calculated interlayer distance in a pristine MoS2 bilayer is found to be 3.00 Å. Insertion of a silicene monolayer enlarges the interlayer separation between MoS2 layers from 3 Å to 6.52 Å, corresponding to an increase of the interlayer separation of

• 3.52 Å. In order to study the possible formation of silicene between the MoS2 monolayers, we consider a buckled 2D silicon cluster (Si37) consisting of six-membered silicon rings. We used a 7 × 7 super-cell structure for the MoS2 bilayer. Initial and equilibrium geometries for both a free-standing as

• resultant fitted spectra. Top and side views of silicene intercalated in bilayer MoS2. Initial (left) and equilibrium (right) structure of (a) a free standing and (b) an intercalated silicon cluster (Si37). Supporting Information Supporting Information File 92: Additional experimental data

Coexistence of strongly buckled germanene phases on Al(111)

• Weimin Wang and
• Roger I. G. Uhrberg

Beilstein J. Nanotechnol. 2017, 8, 1946–1951, doi:10.3762/bjnano.8.195

• bilayer germanene on Cu(111) at room temperature. Scanning tunneling spectroscopy showed a “V” shaped density of states, which was also observed by Zhang et al. [12], who synthesized germanene on MoS2 at room temperature. Al(111) was chosen as a substrate to deposit germanene by Derivaz et al. [13] with

Adsorption and diffusion characteristics of lithium on hydrogenated α- and β-silicene

• Fadil Iyikanat,
• Ali Kandemir,
• Cihan Bacaksiz and
• Hasan Sahin

Beilstein J. Nanotechnol. 2017, 8, 1742–1748, doi:10.3762/bjnano.8.175

• -hydrogenated silicene exhibits ferromagnetic semiconducting behavior with a band gap of 0.95 eV [27]. Hydrogenation leads indirect-to-direct gap transitions in bilayer silicene [28]. In the experimental study of Qiu et al., the ordered and reversible hydrogenation of silicene was performed [29]. Moreover

Parylene C as a versatile dielectric material for organic field-effect transistors

• Tomasz Marszalek,
• Maciej Gazicki-Lipman and
• Jacek Ulanski

Beilstein J. Nanotechnol. 2017, 8, 1532–1545, doi:10.3762/bjnano.8.155

• degradation of IDS, measured in the OFET encapsulated with Parylene C (1 μm) may be attributed to the slow penetration of water vapor and oxygen through the encapsulation layer. The decrease in the permeability of water vapor and oxygen through the bilayer encapsulation film has been attributed to the sealing

• of grain boundaries by the smoothness of the BCB layer. However, it only works when Parylene C/BCB bilayer system is used. By applying a bilayer encapsulation system, the defects in the Parylene C film underneath are blocked by the BCB layer. The permeation path for water vapor and oxygen becomes

Adsorption and electronic properties of pentacene on thin dielectric decoupling layers

• Sebastian Koslowski,
• Daniel Rosenblatt,
• Alexander Kabakchiev,
• Klaus Kuhnke,
• Klaus Kern and
• Uta Schlickum

Beilstein J. Nanotechnol. 2017, 8, 1388–1395, doi:10.3762/bjnano.8.140

• case of Au(111) and Cu(111), KCl grows as a bilayer, whereas on Cu(110), a monolayer growth was observed. The right graph indicates the deviation of the HOMO–LUMO gap of pentacene on the respective surfaces (Egap) from its unperturbed gas-phase gap (Egap,0). Experimentally determined energies for Ea

Vapor-phase-synthesized fluoroacrylate polymer thin films: thermal stability and structural properties

• Paul Christian and
• Anna Maria Coclite

Beilstein J. Nanotechnol. 2017, 8, 933–942, doi:10.3762/bjnano.8.95

• packing of the fluorinated pendant chains into a bilayer structure of distance d = 3.18 ± 0.02 nm (corresponding to a scattering vector qz = 1.98 nm−1) [4]. Thus, the Bragg peak in Figure 5a is identified as the 002 reflection of this lamellar packing (data depicting the 001 reflection is provided in

• -prepared sample. Upon recrystallization under cooling, the Bragg peaks are slightly shifted towards higher q-values (see Figure 5a,b); the bilayer distance is reduced with respect to the as-prepared state and minor relaxation has occurred in the p-PFDA unit cell. While this difference diminishes in

• ; atomic force micrographs depicting larger scales; X-ray reflectivity scan evidencing the bilayer structure of p-PFDA. Acknowledgements The work was funded by the Austrian Science Fund (FWF) [Grant P26993]. The authors gratefully acknowledge Roland Resel for interesting and helpful scientific discussions

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

• electrical characteristics of CuO–graphene bilayer structure has been modified largely due to the electronic interaction at the hybrid interface. The O2 intake capacity of the multilayer graphene results in reversible bipolar resistive switching properties [217]. Zhou et al. prepared graphene-wrapped CuO

Comparison of four methods for the biofunctionalization of gold nanorods by the introduction of sulfhydryl groups to antibodies

• Xuefeng Wang,
• Zhong Mei,
• Yanyan Wang and
• Liang Tang

Beilstein J. Nanotechnol. 2017, 8, 372–380, doi:10.3762/bjnano.8.39

• solution and the CTAB bilayer density [15]. The common ligand exchange is the replacement of the CTAB of GNR with thiol-terminated ligands, such as thiolated poly(ethylene glycol) and mercaptoundecanoic acid [10][11]. These agents can link the amino groups of biomolecules with the carboxylic group from

• cationic surfactant bilayer [17][24], because of the replacement of CTAB by thiolated anti-IgG [17][25]. Anti-IgG were detected in thiolation and nanoconjugates with GNRs, but not in free GNRs, by gel electrophoresis followed by Coomassie brilliant blue staining (Figure S1, Supporting Information File 1

Impact of contact resistance on the electrical properties of MoS₂ transistors at practical operating temperatures

• Filippo Giannazzo,
• Gabriele Fisichella,
• Aurora Piazza,
• Salvatore Di Franco,
• Giuseppe Greco,
• Simonpietro Agnello and
• Fabrizio Roccaforte

Beilstein J. Nanotechnol. 2017, 8, 254–263, doi:10.3762/bjnano.8.28

• to transfer the exfoliated MoS2 flakes onto the SiO2 surface that was previously cleaned using solvents and a soft O2 plasma treatment. Finally, source and drain contacts were obtained by deposition and lift-off of a Ni(50 nm)/Au(100 nm) bilayer. The temperature-dependent electrical characterization