26 research outputs found
Line Defects in Molybdenum Disulfide Layers
Layered molecular materials and especially MoS2 are already accepted as
promising candidates for nanoelectronics. In contrast to the bulk material, the
observed electron mobility in single-layer MoS2 is unexpectedly low. Here we
reveal the occurrence of intrinsic defects in MoS2 layers, known as inversion
domains, where the layer changes its direction through a line defect. The line
defects are observed experimentally by atomic resolution TEM. The structures
were modeled and the stability and electronic properties of the defects were
calculated using quantum-mechanical calculations based on the
Density-Functional Tight-Binding method. The results of these calculations
indicate the occurrence of new states within the band gap of the semiconducting
MoS2. The most stable non-stoichiometric defect structures are observed
experimentally, one of which contains metallic Mo-Mo bonds and another one
bridging S atoms
YS-TaS2 and YxLa1–xS-TaS2 (0 ≤ x ≤ 1) nanotubes: A family of misfit layeredcompounds
We present the analysis of a family of nanotubes (NTs) based on the quaternary misfit layered compound (MLC) YxLa1–xS-TaS2. The NTs were successfully synthesized within the whole range of possible compositions via the chemical vapor transport technique. In-depth analysis of the NTs using electron microscopy and spectroscopy proves the in-phase (partial) substitution of La by Y in the (La,Y)S subsystem and reveals structural changes compared to the previously reported LaS-TaS2 MLC-NTs. The observed structure can be linked to the slightly different lattice parameters of LaS and YS. Raman spectroscopy and infrared transmission measurements reveal the tunability of the plasmonic and vibrational properties. Density-functional theory calculations showed that the YxLa1–xS-TaS2 MLCs are stable in all compositions. Moreover, the calculations indicated that substitution of La by Sc atoms is electronically not favorable, which explains our failed attempt to synthesize these MLC and NTs thereof.A.E. acknowledges the support by Act 211 Government of the Russian Federation, Contract No. 02.A03.21.0006. The support of the Israel Science Foundation (Grant No. 7130970101), Irving and Cherna Moskowitz Center for Nano and Bio-Nano Imaging, and the Perlman Family Foundation and the Kimmel Center for Nanoscale Science (Grant No. 43535000350000) is greatly acknowledged. R.A. gratefully
acknowledges the support from the Spanish Ministry of Economy and Competitiveness (MINECO) through Project Grant MAT2016-79776-P (AEI/FEDER, UE) and from the
European Union H2020 program “ESTEEM3” (823717). S.H. acknowledges funding by the German Research Foundation (HE 7675/1-1). I.P. is the incumbent of the Sharon
Zuckerman Research Fellow Chair.Peer reviewe
Inorganic Fullerene-Like Nanoparticles and Inorganic Nanotubes
Fullerene-like nanoparticles (inorganic fullerenes; IF) and nanotubes of inorganic layered compounds (inorganic nanotubes; INT) combine low dimensionality and nanosize, enhancing the performance of corresponding bulk counterparts in their already known applications, as well as opening new fields of their own [1]. This issue gathers articles from the diverse area of materials science and is devoted to fullerene-like nanoparticles and nanotubes of layered sulfides and boron nitride and collects the most current results obtained at the interface between fundamental research and engineering.[...
On the crystallization of polymer composites with inorganic fullerene-like particles
The effect of a sulfide fullerene-like particle embedded into a polymer has been studied by molecular dynamics simulations on the nanosecond time scale using a mesoscopic Van der Waals force field evaluated for the case of a spherical particle. Even in this approach, neglecting the atomistic features of the surface, the inorganic particle acts as a nucleation agent facilitating the crystallization of the polymeric sample. A consideration of the Van der Waals force field of multi-walled sulfide nanoparticles suggests that in the absence of chemical interactions the size of the nanoparticle is dominating for the adhesion strength, while the number of sulfide layers composing the cage does not play a role. © 2012 the Owner Societies
Stability and electronic properties of rhenium sulfide nanotubes
The structural properties, the stability and the electronic properties of single-walled ReS2 nanotubes are studied for-the first time using the density-functional tight-binding method (DFTB). It is found, that the properties of these nanotubes are determined essentially by the electronic structure causing unique character of intralayer metal-metal bonding within their walls, which evokes their semiconducting character and the highest stiffness after carbon and BN nanotubes
Line Defects in Molybdenum Disulfide Layers
Layered
molecular materials and especially MoS<sub>2</sub> are
already accepted as promising candidates for nanoelectronics. In contrast
to the bulk material, the observed electron mobility in single-layer
MoS<sub>2</sub> is unexpectedly low. Here we reveal the occurrence
of intrinsic defects in MoS<sub>2</sub> layers, known as inversion
domains, where the layer changes its direction through a line defect.
The line defects are observed experimentally by atomic resolution
TEM. The structures were modeled and the stability and electronic
properties of the defects were calculated using quantum-mechanical
calculations based on the Density-Functional Tight-Binding method.
The results of these calculations indicate the occurrence of new states
within the band gap of the semiconducting MoS<sub>2</sub>. The most
stable nonstoichiometric defect structures are observed experimentally,
one of which contains metallic Mo–Mo bonds and another one
bridging S atoms
Line Defects in Molybdenum Disulfide Layers
Layered
molecular materials and especially MoS<sub>2</sub> are
already accepted as promising candidates for nanoelectronics. In contrast
to the bulk material, the observed electron mobility in single-layer
MoS<sub>2</sub> is unexpectedly low. Here we reveal the occurrence
of intrinsic defects in MoS<sub>2</sub> layers, known as inversion
domains, where the layer changes its direction through a line defect.
The line defects are observed experimentally by atomic resolution
TEM. The structures were modeled and the stability and electronic
properties of the defects were calculated using quantum-mechanical
calculations based on the Density-Functional Tight-Binding method.
The results of these calculations indicate the occurrence of new states
within the band gap of the semiconducting MoS<sub>2</sub>. The most
stable nonstoichiometric defect structures are observed experimentally,
one of which contains metallic Mo–Mo bonds and another one
bridging S atoms