Recent highlights in nanoscale and mesoscale friction

• Andrea Vanossi,
• Dirk Dietzel,
• Andre Schirmeisen,
• Ernst Meyer,
• Rémy Pawlak,
• Thilo Glatzel,
• Marcin Kisiel,
• Shigeki Kawai and
• Nicola Manini

Beilstein J. Nanotechnol. 2018, 9, 1995–2014, doi:10.3762/bjnano.9.190

• frictional sliding observed in the case of overlayer/substrate lattice mismatch. Nucleation dynamics characterizes the depinning mechanism of a stiff commensurate colloidal monolayer [167]. In contrast, if the interface is characterized by a lattice mismatch, the presence/absence of static friction depends

Self-assembled quasi-hexagonal arrays of gold nanoparticles with small gaps for surface-enhanced Raman spectroscopy

• Emre Gürdal,
• Simon Dickreuter,
• Fatima Noureddine,
• Pascal Bieschke,
• Dieter P. Kern and
• Monika Fleischer

Beilstein J. Nanotechnol. 2018, 9, 1977–1985, doi:10.3762/bjnano.9.188

• /mL and stirred for 2 days. The micelles were loaded with chlorauric acid (HAuCl4, loading parameter (L = 0.5), Sigma-Aldrich) and stirred again for 2 days. Spin-coating was applied to cover the substrate with a monolayer of the gold-loaded micelles (30 s at 2000 rpm). Electroless deposition A quartz

• features. To measure the SERS signal, the gold nanoparticles were covered with a self-assembled monolayer of 4-MBA. Because the thiol-group of the 4-MBA molecules has a very high affinity for gold [27], and the samples were rinsed thoroughly with ethanol to remove any unbound molecules, we can assume that

Synthesis of hafnium nanoparticles and hafnium nanoparticle films by gas condensation and energetic deposition

• Irini Michelakaki,
• Nikos Boukos,
• Dimitrios A. Dragatogiannis,
• Spyros Stathopoulos,
• Costas A. Charitidis and
• Dimitris Tsoukalas

Beilstein J. Nanotechnol. 2018, 9, 1868–1880, doi:10.3762/bjnano.9.179

• . For this purpose samples with low coverage (monolayer) of Hf NPs were prepared. The coverage with nanoparticles was defined by the deposition time. AFM and TEM images reveal the height and diameter of the NPs. Faceted Hf nanoparticles were formed with a mean size of (diameter × height) 16 nm × 15 nm

Improving the catalytic activity for hydrogen evolution of monolayered SnSe_2(1−x)S_2x by mechanical strain

• Sha Dong and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2018, 9, 1820–1827, doi:10.3762/bjnano.9.173

• non-noble metals and earth-abundant elements is a promising pathway for achieving practical electrochemical water splitting. In this work, the electronic properties and catalytic activity of monolayer SnSe2(1−x)S2x (x = 0–1) under compressive and tensile strain were investigated using density

• functional theory (DFT) computations. The results showed SnSe2(1−x)S2x alloys with continuously changing bandgaps from 0.8 eV for SnSe2 to 1.59 eV for SnS2. The band structure of a SnSe2(1−x)S2x monolayer can be further tuned by applied compressive and tensile strain. Moreover, tensile strain provides a

• direct approach to improve the catalytic activity for the hydrogen evolution reaction (HER) on the basal plane of the SnSe2(1−x)S2x monolayer. SnSeS and SnSe0.5S1.5 monolayers showed the best catalytic activity for HER at a tensile strain of 10%. This work provides a design for improved catalytic

Controllable one-pot synthesis of uniform colloidal TiO₂ particles in a mixed solvent solution for photocatalysis

• Jong Tae Moon,
• Seung Ki Lee and
• Ji Bong Joo

Beilstein J. Nanotechnol. 2018, 9, 1715–1727, doi:10.3762/bjnano.9.163

• (TiO2-400) calcined at a relatively low temperature (400 °C) had a large adsorption capacity in the range of monolayer adsorption (0.1 < P/P0 < 0.25), which indicated highly porous structures with a large BET surface area. However, the amount of monolayer adsorption of the TiO2 samples continuously

Toward the use of CVD-grown MoS₂ nanosheets as field-emission source

• Geetanjali Deokar,
• Nitul S. Rajput,
• Junjie Li,
• Francis Leonard Deepak,
• Wei Ou-Yang,
• Nicolas Reckinger,
• Carla Bittencourt,
• Jean-Francois Colomer and
• Mustapha Jouiad

Beilstein J. Nanotechnol. 2018, 9, 1686–1694, doi:10.3762/bjnano.9.160

• practical applications. Thus, as compared with previously published horizontally aligned monolayer or the vertically aligned MoS2 NSs or nanoflowers, the as-produced NSs present a clear advantage in terms of low turn-on field and high current density. It has been demonstrated that film morphology of the

Free-radical gases on two-dimensional transition-metal disulfides (XS₂, X = Mo/W): robust half-metallicity for efficient nitrogen oxide sensors

• Chunmei Zhang,
• Yalong Jiao,
• Fengxian Ma,
• Sri Kasi Matta,
• Steven Bottle and
• Aijun Du

Beilstein J. Nanotechnol. 2018, 9, 1641–1646, doi:10.3762/bjnano.9.156

• highly challenging work because it requires sensors with an ultra-high level of sensitivity. By using density functional theory, here we demonstrate that the adsorption of a paramagnetic unpaired free radical gas (NO) on a monolayer of XS2 (X = Mo, W) can trigger the transition from semiconductor to half

• ][16], phosphorene [9], siligraphene (SiC5) [10] and molybdenum disulfide (MoS2) [11][17] possess a high specific surface area and high electrical conductivity making them the ideal candidates for gas sensors. In particular, investigations of XS2-based (X = Mo, W) monolayer nanodevices demonstrate that

• , only few possess all necessary properties and many of them are unstable. Therefore, to explore more experimentally feasible and stable half-metallic materials is highly desirable. In this paper, a density functional theory (DFT) study is carried out to show that monolayer XS2 (X = Mo, W) can

Nanoscale electrochemical response of lithium-ion cathodes: a combined study using C-AFM and SIMS

• Jonathan Op de Beeck,
• Nouha Labyedh,
• Alfonso Sepúlveda,
• Valentina Spampinato,
• Alexis Franquet,
• Thierry Conard,
• Philippe M. Vereecken,
• Wilfried Vandervorst and
• Umberto Celano

Beilstein J. Nanotechnol. 2018, 9, 1623–1628, doi:10.3762/bjnano.9.154

• . Static SIMS is known to be probing only the outermost monolayer with minimal disturbance ensuring the information we obtain is only the surface chemical composition [15]. In essence, the SIMS results provide the 2D distribution map of the Li concentration at the surface with a clear distinction between

Light extraction efficiency enhancement of flip-chip blue light-emitting diodes by anodic aluminum oxide

• Yi-Ru Huang,
• Yao-Ching Chiu,
• Kuan-Chieh Huang,
• Shao-Ying Ting,
• Po-Jui Chiang,
• Chih-Ming Lai,
• Chun-Ping Jen,
• Snow H. Tseng and
• Hsiang-Chen Wang

Beilstein J. Nanotechnol. 2018, 9, 1602–1612, doi:10.3762/bjnano.9.152

• with Ga-doped zinc oxide (GZO)/GaN as the base layer and then reducing the total reflectivity by changing the shape, thickness, and density of the microstructure through dry etching [12]. Li et al. increased the LEE of an InGaN-monolayer quantum-well LED by 1.8–1.9 times relative to that of a

The electrical conductivity of CNT/graphene composites: a new method for accelerating transmission function calculations

• Olga E. Glukhova and
• Dmitriy S. Shmygin

Beilstein J. Nanotechnol. 2018, 9, 1254–1262, doi:10.3762/bjnano.9.117

• using the example of a graphene monolayer. Figure la shows the considered system, that is, the unit cell connected to the electrodes. Since we calculated the conductance of this material (graphene), the same cells act as electrodes. Electrodes are translated to infinity along the Y-direction, and they

• Equations 1–3 with different values of N are shown in Figure 1b. For a small step of the decomposition dk = 0.1 1/Å (N = 15), the function has a step-like form. When the step of the decomposition is reduced to dk = 0.0015 1/Å (N = 984), the curve takes the correct well-known form for a graphene monolayer

• hexagons, but also defects in the form of pentagons, heptagons and octagons. In order to calculate the electrical conductance in the X- and Y-directions, as in the case of the graphene monolayer, a central supercell and supercell electrodes are separated (see Figure 5b). The conductance calculation scheme

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

• –correlation functional [13]. A Monkhorst–Pack k-points grid [14] of 9 × 3 × 2 and 9 × 3 × 1 was used for sampling the first Brillouin zone for bulk and monolayer for geometry optimizations. Both bulk and monolayer systems are set for relaxing until residual force and energy converged to 0.005 eV/Å and 10−7eV

• , respectively. To study 2D monolayer systems under periodic boundary conditions, a vacuum layer of about 15 Å was introduced to minimize the spurious interaction between neighboring layers. The electronic band structure is predicted through hybrid density functional theory based on the Heyd–Scuseria–Ernzerhof

• bulk equivalent of the same material”, Ef: where, E2D and E3D are the energies of the monolayer and the bulk material, respectively. n2D and n3D are the number of atoms present in the unit cells considered for the calculations [18][19][20]. The optical properties are evaluated by determining the

Heterostuctures of 4-(chloromethyl)phenyltrichlorosilane and 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine prepared on Si(111) using particle lithography: Nanoscale characterization of the main steps of nanopatterning

• Phillip C. Chambers and
• Jayne C. Garno

Beilstein J. Nanotechnol. 2018, 9, 1211–1219, doi:10.3762/bjnano.9.112

• rinsed from the sample. The uniform color contrast observed in the phase image (Figure 2d) indicates that the nanoholes do not contain OTS. The approximate surface coverage of the OTS film measured 97%. The average thickness of the OTS monolayer was measured to be 0.7 nm. The measurements indicate

• submonolayer surface coverage relative to the ideal height (2.6 nm) of a densely packed OTS monolayer [25][41]. The nanoholes within OTS that were generated with particle lithography will serve as sites for further reactions with CMPS and H2TPyP to produce multicomponent nanostructures. Methyl-terminated OTS

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

• all relevant band structure variations induced by SOC. In this work, the non-relativistic or scalar-relativistic Kohn–Sham Hamiltonian is obtained from the CRYSTAL code and the SOC term is added a posteriori. As an example, we apply this method to the Bi(111) monolayer, a paradigmatic 2D topological

• , we have chosen to apply our implementation to Sb and Bi, which are prototypical topological materials where SOC plays a crucial role. Despite being elemental, they present a broad range of behaviors. While bulk Bi is a trivial semimetal, a Bi(111) monolayer is a 2D topological insulator (TI) [27]. Sb

• few-layers in the (111) direction, typically for more than ≈7 layers, behave as a 3D topological semimetal, while the Sb(111) monolayer is a trivial indirect-gap semiconductor. In order for our SOC implementation to be of practical use, it should capture these trivial/non-trivial topological

Electro-optical interfacial effects on a graphene/π-conjugated organic semiconductor hybrid system

• Karolline A. S. Araujo,
• Luiz A. Cury,
• Matheus J. S. Matos,
• Thales F. D. Fernandes,
• Luiz G. Cançado and
• Bernardo R. A. Neves

Beilstein J. Nanotechnol. 2018, 9, 963–974, doi:10.3762/bjnano.9.90

• probe microscopy, optical spectroscopy (photoluminescence and Raman) and ab initio calculations. The graphene/RA interaction induces the formation of a well-organized π-conjugated self-assembled monolayer (SAM) at the interface. Such structural organization leads to the high optical emission efficiency

• of the RA SAM, even at room temperature. Additionally, photo-assisted electrical force microscopy, photo-assisted scanning Kelvin probe microscopy and Raman spectroscopy indicate a RA-induced graphene doping and photo-charge generation. Finally, the optical excitation of the RA monolayer generates

• interfacial effects. Scanning probe microscopy (SPM) and Raman scattering experiments, along with first-principles calculations, reveal the presence of a highly ordered RA self-assembled monolayer atop graphene and graphite. The electro-optical characterization of the hybrid system discloses interfacial

Scanning speed phenomenon in contact-resonance atomic force microscopy

• Christopher C. Glover,
• Jason P. Killgore and
• Ryan C. Tung

Beilstein J. Nanotechnol. 2018, 9, 945–952, doi:10.3762/bjnano.9.87

• , humidity, and loading conditions [17][26][28][29][30][31][32]. Researchers using molecular dynamic (MD) simulations have also found that “at the monolayer coverage, water forms a 2-D H-bonded network in an epitaxial relationship with the mica lattice” [17]. The first complete layer of water is thought to

Comparative study of antibacterial properties of polystyrene films with TiO_x and Cu nanoparticles fabricated using cluster beam technique

• Vladimir N. Popok,
• Cesarino M. Jeppesen,
• Peter Fojan,
• Anna Kuzminova,
• Jan Hanuš and
• Ondřej Kylián

Beilstein J. Nanotechnol. 2018, 9, 861–869, doi:10.3762/bjnano.9.80

• of the NP embedding. For the antibacterial tests, the samples with higher surface cluster coverage (slightly more than one monolayer of particles) are used. A very similar tendency for immersion is found for Ti NPs on PS. Therefore, the AFM images are not presented. The AFM measurements also show

Valley-selective directional emission from a transition-metal dichalcogenide monolayer mediated by a plasmonic nanoantenna

• Haitao Chen,
• Mingkai Liu,
• Lei Xu and
• Dragomir N. Neshev

Beilstein J. Nanotechnol. 2018, 9, 780–788, doi:10.3762/bjnano.9.71

• physical phenomena and great potential applications in valleytronics. Results: Here, we propose a TMDC–nanoantenna system that could effectively enhance and direct emission from the two valleys in TMDCs into diametrically opposite directions. By mimicking the emission from each valley of the monolayer of

• polarization; Introduction The inversion-symmetry breaking and quantum confinement in monolayer TMDCs offer unprecedented opportunities to explore valley-based physics and applications [1][2][3]. The valley pseudospin is associated with the degenerate energy extrema in momentum space [3]. In monolayer TMDCs

• [6][7][8][9][10]. In particular, monolayer TMDCs with direct bandgap at the K and K′ points [11] make it possible to control the valley degree freedom entirely optically. Optical pumping of excitons of a specific valley polarization has been demonstrated by polarization-resolved photoluminescence (PL

Synthesis and characterization of two new TiO₂-containing benzothiazole-based imine composites for organic device applications

• Anna Różycka,
• Agnieszka Iwan,
• Krzysztof Artur Bogdanowicz,
• Michal Filapek,
• Natalia Górska,
• Damian Pociecha,
• Marek Malinowski,
• Patryk Fryń,
• Agnieszka Hreniak,
• Jakub Rysz,
• Paweł Dąbczyński and
• Monika Marzec

Beilstein J. Nanotechnol. 2018, 9, 721–739, doi:10.3762/bjnano.9.67

• isotherms are typical for non-porous or macroporous materials, for which unrestricted multilayer adsorption can occurs. In the isotherm, the characteristic bond (the knee) was found at low pressure, indicating the point at which the creation of a monolayer was completed. On the other hand, type IV is

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

• -controlled box (pressure ranged from 1000 to about 5 × 10−5 mbar). A laser power of 2 mW was used, and the laser spot diameter was about 1.5 µm. Pressure-dependent measurements were carried out in a typical graphene monolayer and a bilayer low-defect region. Raman spectra of graphene on various substrates

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

• 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

Sensing behavior of flower-shaped MoS₂ nanoflakes: case study with methanol and xylene

• Maryam Barzegar,
• Masoud Berahman and
• Azam Iraji zad

Beilstein J. Nanotechnol. 2018, 9, 608–615, doi:10.3762/bjnano.9.57

• the testing period. The chemoresistance response is defined as (Rair – Rgas)/Rair where Rair and Rgas are the resistance in N2 and the mixed gases in different concentrations, respectively. Simulation A super-cell containing 25 primitive unit cells of monolayer MoS2 was considered as the pristine

• differences, we performed a simulation study on the pristine monolayer and similar surface with sulfur vacancy of MoS2 in the presence of xylene and methanol molecules. Xylene shows almost no interaction with pristine MoS2 while a van der Waals interaction happens in the case of sulfur vacancy, which leads to

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

• only present in monolayer graphene, but also in carbon structures that have turbostratic graphite (TGr) as part of their components, such as MWNTs. This can be confirmed by the Raman spectra presented in Figure 2. Both structures, monolayer and TGr, are represented as Lorentzian peaks, however, TGr has

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

• biological species recognition with minimum nonspecific attachment. Herein, a straightforward approach utilizing chemical lift-off lithography to create a diluted self-assembled monolayer matrix for anchoring diverse biological probes is introduced. The strategy encompasses convenient operation, well-tunable

• pattern feature and size, large-area fabrication, high resolution and fidelity control, and the ability to functionalize versatile bioarrays. With the interface-contact-induced reaction, a preformed alkanethiol self-assembled monolayer on a Au surface is ruptured and a unique defect-rich diluted matrix is

• lift-off lithography; patterning; self-assembled monolayer; Introduction Patterning on the micro- to nanoscale plays a key role in modern scientific and engineering research fields. Particularly, the creation of bioactive surfaces with well-defined geometries has drawn lots of attention due to its

Review: Electrostatically actuated nanobeam-based nanoelectromechanical switches – materials solutions and operational conditions

• Liga Jasulaneca,
• Jelena Kosmaca,
• Raimonds Meija,
• Jana Andzane and
• Donats Erts

Beilstein J. Nanotechnol. 2018, 9, 271–300, doi:10.3762/bjnano.9.29

• mechanical strain [124][125], their electrical breakdown and mass loss caused by field evaporation [126]. Graphene: For fabricating NEM switches, monolayer [24][25][26][27] as well as few-layer [28][29][30][31] graphene materials are used. The mechanical properties are decisive for selecting the number of

Dopant-stimulated growth of GaN nanotube-like nanostructures on Si(111) by molecular beam epitaxy

• Alexey D. Bolshakov,
• Alexey M. Mozharov,
• Georgiy A. Sapunov,
• Igor V. Shtrom,
• Nickolay V. Sibirev,
• Vladimir V. Fedorov,
• Evgeniy V. Ubyivovk,
• Maria Tchernycheva,
• George E. Cirlin and
• Ivan S. Mukhin

Beilstein J. Nanotechnol. 2018, 9, 146–154, doi:10.3762/bjnano.9.17

• flux (species/nm2s). Putting all expressions above together, we arrive at: From another point of view, the lateral growth of a new monolayer on the top facet relates to direct impingement and diffusion flux from the sidewalls and from the hollow part (). Therefore, another material balance equation