Materials nanoarchitectonics at two-dimensional liquid interfaces

• Katsuhiko Ariga,
• Michio Matsumoto,
• Taizo Mori and
• Lok Kumar Shrestha

Beilstein J. Nanotechnol. 2019, 10, 1559–1587, doi:10.3762/bjnano.10.153

• compared to similar cells prepared with pristine C60 molecules. C60 molecules in a one-dimensional van der Waals solid preserve the electronic structure of C60, but they crystallise in a hexagonal close-packed structure that is different from the cubic crystal structure of pristine C60 molecular crystals

Flexible freestanding MoS₂-based composite paper for energy conversion and storage

• Florian Zoller,
• Jan Luxa,
• Thomas Bein,
• Dina Fattakhova-Rohlfing,
• Daniel Bouša and
• Zdeněk Sofer

Beilstein J. Nanotechnol. 2019, 10, 1488–1496, doi:10.3762/bjnano.10.147

• der Waals spaces between the MoS2 layers forming LixMoS2 accompanied by a phase transformation from trigonal prismatic (2H) to octahedral (1T) (see the following Equation 2) [8][20][21]. The peak at ≈0.3 V corresponds to the conversion of the previously formed LixMoS2 into metallic Mo and LiS2 (see

• composite paper. The measurements were performed at a scan rate of 0.1 mV·s−1 in the voltage range of 0.01–3.0 V vs Li/Li+. In the initial cathodic scan, two dominant reduction peaks at around 1.0 and 0.3 V are detectable (Figure 5a). The first is associated with the insertion of lithium ions into the van

Imaging the surface potential at the steps on the rutile TiO₂(110) surface by Kelvin probe force microscopy

• Masato Miyazaki,
• Huan Fei Wen,
• Quanzhen Zhang,
• Yuuki Adachi,
• Jan Brndiar,
• Ivan Štich,
• Yan Jun Li and
• Yasuhiro Sugawara

Beilstein J. Nanotechnol. 2019, 10, 1228–1236, doi:10.3762/bjnano.10.122

• distance. The long-range contribution (ΔfLR), van der Waals or electrostatic forces, to the Δf curve was fitted to the inverse power law z−n [52]. By subtracting the ΔfLR curve from the Δf curve, we obtained the short-range contribution (ΔfSR). Finally, the ΔfSR curve was converted to the short-range force

• profile perpendicular to the direction (black line in Figure 2a), the height of the step was about 200 pm. The measured step height of 200 pm was smaller than real step height of 325 pm [32], which can be explained by the large tip–sample distance. Actually, at the large tip–sample distances, the van der

• Waals force is dominant and the contribution of the force from the tip apex becomes weak and the force from the rest of the cantilever becomes significant. Therefore, the observed height of step was smaller than that of the real one. Before the experiments, we verified that the distance calibration of

Pure and mixed ordered monolayers of tetracyano-2,6-naphthoquinodimethane and hexathiapentacene on the Ag(100) surface

• Robert Harbers,
• Timo Heepenstrick,
• Dmitrii F. Perepichka and
• Moritz Sokolowski

Beilstein J. Nanotechnol. 2019, 10, 1188–1199, doi:10.3762/bjnano.10.118

• 150.2 Å2 and is large enough for containing one flat-lying HTPEN molecule, as illustrated in Figure 2b. The molecular geometry used for the hard-sphere model of HTPEN (Figure 2b) is based on the crystal structure data of HTPEN [19] and the van der Waals radii taken from [32]. Table 1 shows all geometric

• distances from [35], and van der Waals radii from [32]. The structure is composed of parallel rows of molecules aligned along their long axes. The major intermolecular interactions are given by hydrogen bonds between the four cyano groups at the corners and hydrogen atoms on the long sides of the molecule

• model of the unit cell (Figure 5b) is based on the assumption of flat-lying molecules. It indicates a ca. 0.5 Å overlap of the van der Waals radii of the peripheral atoms. We consider this as meaningful, although there is some uncertainty about the exact size of the footprint of the molecule on the Ag

Tailoring the magnetic properties of cobalt ferrite nanoparticles using the polyol process

• Malek Bibani,
• Romain Breitwieser,
• Alex Aubert,
• Vincent Loyau,
• Silvana Mercone,
• Souad Ammar and
• Fayna Mammeri

Beilstein J. Nanotechnol. 2019, 10, 1166–1176, doi:10.3762/bjnano.10.116

• after 15 h of reaction are clearly more aggregated than those obtained after 6 h, most likely due to stronger van der Waals and/or magnetostatic interactions between bigger nanoparticles (promoted by the drying of the NPs during the sample preparation for TEM) resulting in the clustering of particles

Synthesis and characterization of quaternary La(Sr)S–TaS₂ misfit-layered nanotubes

• Marco Serra,
• Erumpukuthickal Ashokkumar Anumol,
• Dalit Stolovas,
• Iddo Pinkas,
• Ernesto Joselevich,
• Reshef Tenne,
• Andrey Enyashin and
• Francis Leonard Deepak

Beilstein J. Nanotechnol. 2019, 10, 1112–1124, doi:10.3762/bjnano.10.111

• van der Waals forces. Frequently, the difference in the work function between the MX and TX2 slabs leads to a partial charge transfer from the MX slab to that of TX2. This charge transfer induces polar interactions between the layers juxtaposing on the van der Waals forces [29]. As the constituting

• many years later [33][34]. Importantly also, the hexagonal CrS2 (VS2) is not a stable polymorph unless it is intercalated in the galleries of the van der Waals gap by an electron donor (Lewis base). Incidentally, in [32] the authors mention that: “Another type of crystals with a "hollow-rod" shape

Structural and optical properties of penicillamine-protected gold nanocluster fractions separated by sequential size-selective fractionation

• Xiupei Yang,
• Zhengli Yang,
• Fenglin Tang,
• Jing Xu,
• Maoxue Zhang and
• Martin M. F. Choi

Beilstein J. Nanotechnol. 2019, 10, 955–966, doi:10.3762/bjnano.10.96

• precipitation technique can reduce the ability of a solvent to disperse clusters by adding a miscible non-solvent to the cluster agglomeration point. The larger clusters are first aggregated due to the greater van der Waals attraction between the clusters, and the clusters aggregated can be precipitated by

Capillary force-induced superlattice variation atop a nanometer-wide graphene flake and its moiré origin studied by STM

• Loji K. Thomas and
• Michael Reichling

Beilstein J. Nanotechnol. 2019, 10, 804–810, doi:10.3762/bjnano.10.80

• direction (numbered (1)) and folding axis (numbered (2)) along two arm-chair crystallographic directions that differ by 120°, in agreement with previous studies [5][9][21][34]. Theory There are three significant forces existing at a solid–liquid interface [17]: (a) van der Waals; (b) electrostatic

• force is known to be many orders of magnitude higher than electrostatic or van der Waals interactions [17]. The graphene flake of area 160 × 182 nm2 has undergone three processes as shown in Figure 3c, i.e., a rotation, a tearing along the arm-chair direction for an extent b = 15 nm, and a partial

• arm-chair direction can be found, which amounts to 172 eV. The interlayer binding energy in graphite is 44 meV/atom which is the van der Waals barrier that needs to be overcome for rotation to happen [45]. Theoretical studies showed that the energy barrier for rotation of graphene flakes on graphite

Trapping polysulfide on two-dimensional molybdenum disulfide for Li–S batteries through phase selection with optimized binding

• Sha Dong,
• Xiaoli Sun and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2019, 10, 774–780, doi:10.3762/bjnano.10.77

• 3.99 and 3.67 Å, respectively. The large distance and the small binding strength of S8 on 2H-MoS2 and 1T'-MoS2 monolayers indicate that the interaction mainly originates from van der Waals interactions. To understand the binding between LPSs and the 2HMoS2- and 1T'-MoS2 monolayers, the charge-density

Features and advantages of flexible silicon nanowires for SERS applications

• Hrvoje Gebavi,
• Vlatko Gašparić,
• Dubravko Risović,
• Nikola Baran,
• Paweł Henryk Albrycht and
• Mile Ivanda

Beilstein J. Nanotechnol. 2019, 10, 725–734, doi:10.3762/bjnano.10.72

• S16). As reported in [42] we assume that capillary forces dominate over van der Waals forces by several orders of magnitude. During drying, the adhesion between liquid and SiNW surface pulls and bends the SiNWs, changing the substrate morphology and consequently increasing the SERS intensity. Water

The effect of translation on the binding energy for transition-metal porphyrines adsorbed on Ag(111) surface

• Luiza Buimaga-Iarinca and
• Cristian Morari

Beilstein J. Nanotechnol. 2019, 10, 706–717, doi:10.3762/bjnano.10.70

• are detailed here as resulted from DFT calculations. Van der Waals interactions as well as the strong correlation in 3d orbitals of transition metals were taken into account in all calculations, including the structural relaxation. For each system we investigate four relative positions of the metallic

• molecule–surface charge transfer, analyzed for different geometric configurations allows us to propose qualitative models, relevant for the understanding of the self-assembly processes and related phenomena. Keywords: Ag(111) surface; DFT+U; metal porphyrine; van der Waals; Introduction Metalloporphyrins

• . Such modifications of the electronic structure are of great interest for all potential applications. Theoretical assessment of the adsorption mechanism of TMPP on silver in the framework of DFT ask for an accurate estimation of the van der Waals dispersive interactions, which are expected to be

Self-assembly and wetting properties of gold nanorod–CTAB molecules on HOPG

• Imtiaz Ahmad,
• Floor Derkink,
• Tim Boulogne,
• Pantelis Bampoulis,
• Harold J. W. Zandvliet,
• Hidayat Ullah Khan,
• Rahim Jan and
• E. Stefan Kooij

Beilstein J. Nanotechnol. 2019, 10, 696–705, doi:10.3762/bjnano.10.69

• extended along the substrate plane. Such a configuration of CTAB molecules oriented parallel to the HOPG surface has been observed experimentally [53], where van der Waals interactions are dominant between molecules and the substrate. The main focus of the present work is to investigate CTAB

Topochemical engineering of composite hybrid fibers using layered double hydroxides and abietic acid

• Liji Sobhana,
• Lokesh Kesavan,
• Jan Gustafsson and
• Pedro Fardim

Beilstein J. Nanotechnol. 2019, 10, 589–605, doi:10.3762/bjnano.10.60

• LDH-hybridized fibers (HF). The results revealed a variety of correlations between materials and their properties due to characteristic surface morphology, functional groups, hydrogen bonding and natural co-materials such as lignin and hemicelluloses. Attractive and repulsive van der Waals forces

• . The present work focuses on stacking abietic acid and cellulose on each side of LDHs via van der Waals forces of hydrogen bonding. Thus, LDH works as an assembling agent. The raw materials used in this study were bleached pine kraft pulp and unbleached spruce kraft pulp. Bleaching is a process in

Direct observation of the CVD growth of monolayer MoS₂ using in situ optical spectroscopy

• Claudia Beatriz López-Posadas,
• Yaxu Wei,
• Wanfu Shen,
• Daniel Kahr,
• Michael Hohage and
• Lidong Sun

Beilstein J. Nanotechnol. 2019, 10, 557–564, doi:10.3762/bjnano.10.57

• is negligible, for the van der Waals epitaxy of MoS2 on the transparent sapphire substrate, the DT spectrum can thus be generally associated with the absorption of the adlayer. Consequently, the growth can be monitored in situ and in real time, and the detailed information associated with the

Mo-doped boron nitride monolayer as a promising single-atom electrocatalyst for CO₂ conversion

• Qianyi Cui,
• Gangqiang Qin,
• Weihua Wang,
• Lixiang Sun,
• Aijun Du and
• Qiao Sun

Beilstein J. Nanotechnol. 2019, 10, 540–548, doi:10.3762/bjnano.10.55

• Ernzerhof (PBE) [56] functional within the generalized gradient approximation (GGA) [57]. The van der Waals (vdW) interactions were described using the empirical correction in Grimme’s scheme [58]. The calculational method has been successfully used for the investigation of selective adsorption and reaction

Mechanical and thermodynamic properties of Aβ₄₂, Aβ₄₀, and α-synuclein fibrils: a coarse-grained method to complement experimental studies

• Adolfo B. Poma,
• Horacio V. Guzman,
• Mai Suan Li and
• Panagiotis E. Theodorakis

Beilstein J. Nanotechnol. 2019, 10, 500–513, doi:10.3762/bjnano.10.51

• to a van der Waals radius, as proposed by Tsai and co-workers [49]. A sphere with the radius enlarged by a factor of 1.24 is built around the atom. If two amino acids have heavy atoms with overlapping spheres, then we consider a native contact between those two Cα atoms. In Figure 2, we show the CG

Polymorphic self-assembly of pyrazine-based tectons at the solution–solid interface

• Achintya Jana,
• Puneet Mishra and
• Neeladri Das

Beilstein J. Nanotechnol. 2019, 10, 494–499, doi:10.3762/bjnano.10.50

• images suggests van der Waals interactions, instead of hydrogen bonding, between the molecules in adjacent linear chains. Thus only the pyridyl nitrogen atoms are responsible for the molecular ordering observed in region I. On the other hand, in region II both the pyridyl nitrogen (N2) and the pyrazine

One-step nonhydrolytic sol–gel synthesis of mesoporous TiO₂ phosphonate hybrid materials

• Yanhui Wang,
• P. Hubert Mutin and
• Johan G. Alauzun

Beilstein J. Nanotechnol. 2019, 10, 356–362, doi:10.3762/bjnano.10.35

• bonds (e.g., van der Waals or hydrogen bonds), while in Class II hybrid materials, they are linked by stronger ionocovalent or covalent bonds [8]. The majority of Class II hybrid materials utilize the stability of the Si–C bond and are based on organosilsesquioxane (R–SiO1.5) or bridged

Nitrous oxide as an effective AFM tip functionalization: a comparative study

• Taras Chutora,
• Bruno de la Torre,
• Pingo Mutombo,
• Jack Hellerstedt,
• Jaromír Kopeček,
• Pavel Jelínek and
• Martin Švec

Beilstein J. Nanotechnol. 2019, 10, 315–321, doi:10.3762/bjnano.10.30

• atomic forces and the total energy were found to be below 10−2 eV/Å and 10−5 eV, respectively. A Monkhorst–Pack grid of 3 × 3 × 1 was used for integration in the Brillouin zone. DFT calculations were performed at the GGA-PBE level including the Tkatchenko–Scheffler treatment of the van der Waals

• probe-particle model [32][45], which takes into account van der Waals (vdW) and electrostatic interactions between the tip and the sample. The calculations were performed varying the effective charge of the probe particle in order to obtain the best possible agreement between the experimental findings

Investigation of CVD graphene as-grown on Cu foil using simultaneous scanning tunneling/atomic force microscopy

• Majid Fazeli Jadidi,
• Umut Kamber,
• Oğuzhan Gürlü and
• H. Özgür Özer

Beilstein J. Nanotechnol. 2018, 9, 2953–2959, doi:10.3762/bjnano.9.274

• explicable with the additional effect of electrostatic forces in the experiments. The sample bias voltage values used in the experiments (up to 500 mV) would result in considerable electrostatic force between the tip and the sample. Also, tips with relatively large cone angles would result in van der Waals

• der Waals (vdW) interaction for a small tip structure only, but not the electrostatic force. The discrepancy in the value of the maximum attractive force and the interaction range of the total measured force, which are much larger than the values derived from the theoretical calculations, is

• maximum attractive force is about 7 nN for both sites. Ondracek et al. calculated the maximum attractive force between a tungsten tip and carbon and hollow sites on graphene to be about 2 nN [25]. However, in their calculations they took into account the short-range interaction and the longer-range van

In situ characterization of nanoscale contaminations adsorbed in air using atomic force microscopy

• Jesús S. Lacasa,
• Lisa Almonte and
• Jaime Colchero

Beilstein J. Nanotechnol. 2018, 9, 2925–2935, doi:10.3762/bjnano.9.271

• contamination; tip cleaning; tip–sample interaction; van der Waals interaction; Introduction Surface science is fundamental to understand many processes in industrial applications, environmental science, biology, medicine and phenomena such as self-assembly [1], friction [2][3] and wetting [4]. In any study

• more detail elsewhere [42], data can be acquired in the (true) non-contact regime (nc-DAFM), where only van der Waals and electrostatic interaction is present. In this work we will assume that the tip–sample system can be described by a metallic tip interacting electrostatically with a metallic sample

• ) = πε0R/d2. Then, the total frequency-shift induced by the tip–sample interaction is: where the first term containing the Hamaker constant A describes the van der Waals interaction and the second term describes the electrostatic interaction. We note that the chemical composition of the sample will

Layered calcium phenylphosphonate: a hybrid material for a new generation of nanofillers

• Kateřina Kopecká,
• Ludvík Beneš,
• Klára Melánová,
• Vítězslav Zima,
• Petr Knotek and
• Kateřina Zetková

Beilstein J. Nanotechnol. 2018, 9, 2906–2915, doi:10.3762/bjnano.9.269

• differ with the metal and organic group incorporated in their structure, the main characteristic remains the same: a strong in-plane bonding in combination with weak van der Waals interactions between the planes. This arrangement enables their use as a host material in intercalation chemistry and as a

• precursor for the preparation of nanosheets by exfoliation. Exfoliation is a process whereby thin sheets of material are completely separated from the bulk. This happens when cohesive forces between the adjacent planes, which are usually caused by van der Waals interactions, are overcome. Mechanical or

Nanostructure-induced performance degradation of WO₃·nH₂O for energy conversion and storage devices

• Zhenyin Hai,
• Mohammad Karbalaei Akbari,
• Zihan Wei,
• Danfeng Cui,
• Chenyang Xue,
• Hongyan Xu,
• Philippe M. Heynderickx,
• Francis Verpoort and
• Serge Zhuiykov

Beilstein J. Nanotechnol. 2018, 9, 2845–2854, doi:10.3762/bjnano.9.265

• in a faster performance degradation, due to its weak interlayer van der Waals forces, even though it outranks the 3D network structure in terms of improved electronic properties. The structural transformation of 2D layered WO3·nH2O into 3D nanostructures is observed via ex situ Raman measurements

• layered transition metal oxides. Keywords: 2D layered oxides; interlayer water; van der Waals interaction; WO3·nH2O; Introduction Within the less than 20 years since the successful exfoliation of atomically thin graphene, 2D layered nanomaterials have been contributing greatly to the advances of

• , revealing that the weakness of layered 2D WO3·nH2O originates from weak interlayer van der Waals interactions. The faster performance degradation in electrochemical tests of 2D layered WO3·nH2O further indicated the structural instability of 2D nanostructures compared to 3D nanostructures. The structural

Graphene-enhanced metal oxide gas sensors at room temperature: a review

• Dongjin Sun,
• Yifan Luo,
• Marc Debliquy and
• Chao Zhang

Beilstein J. Nanotechnol. 2018, 9, 2832–2844, doi:10.3762/bjnano.9.264

• sensors based on rGO exhibited a rapid and high response to target gas at room temperature. However, these sensors show a common shortage. Since the binding force between graphene and gas molecules is van der Waals force or even covalent bonds [6], the recovery time is too long, sometimes recovery is not

Accurate control of the covalent functionalization of single-walled carbon nanotubes for the electro-enzymatically controlled oxidation of biomolecules

• Naoual Allali,
• Veronika Urbanova,
• Mathieu Etienne,
• Xavier Devaux,
• Martine Mallet,
• Brigitte Vigolo,
• Jean-Joseph Adjizian,
• Chris P. Ewels,
• Sven Oberg,
• Alexander V. Soldatov,
• Edward McRae,
• Yves Fort,
• Manuel Dossot and
• Victor Mamane

Beilstein J. Nanotechnol. 2018, 9, 2750–2762, doi:10.3762/bjnano.9.257

• of water. Once water was added, van der Waals and dipolar interactions between the water molecules and the ETG chain effectively blocked chain flexion and maintained the ferrocene unit at a distance of over 6.41 Å from the tube surface throughout the simulation (Figure 12B). Even for HIPCO-FcETG2