Search results

Search for "dislocations" in Full Text gives 74 result(s) in Beilstein Journal of Nanotechnology.

Lower nanometer-scale size limit for the deformation of a metallic glass by shear transformations revealed by quantitative AFM indentation

  • Arnaud Caron and
  • Roland Bennewitz

Beilstein J. Nanotechnol. 2015, 6, 1721–1732, doi:10.3762/bjnano.6.176

Graphical Abstract
  • ability to apply larger strains than spherical indenters. Analysis of the curvature of load–displacement curves and of the occurrence of sharp pop-ins have further been used to study mechanisms of plastic deformation such as the generation and multiplication of dislocations in crystalline metals [3] or
  • by means of atomic force microscopes (AFM indentation) has been used to observe the nucleation and gliding of single dislocations in a KBr(100) single crystal [7] and in Cu(100) [8]. Pop-ins were observed in load–displacement curves, and the pop-in length observed in AFM-indentation was in the range
  • other, demonstrating the good reproducibility of the method. The P–δ curves on the crystalline Pt(111) show clear pop-ins. In the low load part of indentation curves (P = 0.6–1.4 µN) the pop-ins have a length of the order of 1 Å and are attributed to the activation of single dislocations. The load
PDF
Album
Full Research Paper
Published 13 Aug 2015

Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials

  • Xiaoxing Ke,
  • Carla Bittencourt and
  • Gustaaf Van Tendeloo

Beilstein J. Nanotechnol. 2015, 6, 1541–1557, doi:10.3762/bjnano.6.158

Graphical Abstract
  • vacancies, dislocations, grain boundaries and strain can be revealed in great detail. The fundamental understanding of CNTs, particularly of graphene in the past decade, have largely benefited from the development in electron microscopy. Taking CNTs again as an example, the direct imaging of a zig-zag
PDF
Album
Review
Published 16 Jul 2015

Thermal treatment of magnetite nanoparticles

  • Beata Kalska-Szostko,
  • Urszula Wykowska,
  • Dariusz Satula and
  • Per Nordblad

Beilstein J. Nanotechnol. 2015, 6, 1385–1396, doi:10.3762/bjnano.6.143

Graphical Abstract
  • boundaries and dislocations, and therefore, more room for oxide penetration, which significantly facilitates the oxidation process. Conclusion The performed experiments show that thermal stability of magnetite nanoparticles is dependent on the fabrication procedure. The temperature scans, combined with
PDF
Album
Full Research Paper
Published 23 Jun 2015

Addition of Zn during the phosphine-based synthesis of indium phospide quantum dots: doping and surface passivation

  • Natalia E. Mordvinova,
  • Alexander A. Vinokurov,
  • Oleg I. Lebedev,
  • Tatiana A. Kuznetsova and
  • Sergey G. Dorofeev

Beilstein J. Nanotechnol. 2015, 6, 1237–1246, doi:10.3762/bjnano.6.127

Graphical Abstract
  • scattering region. This discrepancy can be explained by fact that the contrast in bright-field low-magnification TEM is a mass-thickness contrast, which arises from Rutherford elastic scattering of electrons, rather than a diffraction or an amplitude contrast in the case of dislocations and high resolution
PDF
Album
Full Research Paper
Published 01 Jun 2015

On the structure of grain/interphase boundaries and interfaces

  • K. Anantha Padmanabhan and
  • Herbert Gleiter

Beilstein J. Nanotechnol. 2014, 5, 1603–1615, doi:10.3762/bjnano.5.172

Graphical Abstract
  • the number of dislocations, i.e., it increases with an increasing boundary misorientation in the low-angle region. (b) For high-angle GBs, the coincidence number alone is not a decisive parameter, but knowledge about the GB plane is essential, i.e., whether the GB is coherent or not. For example, for
  • because the loop formation displaces the basic sliding unit in the direction of stress only by about a tenth of the interatomic spacing in the boundary region.) In this sense, the speculation found in the literature that the motion of extrinsic boundary dislocations could cause grain boundary/interface
  • sliding is justified. Assuming the extrinsic boundary dislocations to be discrete, Nazarov and coworkers (for a summary see [63]) have been able to predict accurately the grain boundary excess energy and the additional free volume/lateral expansion found in severely plastically deformed materials. Now
PDF
Album
Review
Published 22 Sep 2014

Topology assisted self-organization of colloidal nanoparticles: application to 2D large-scale nanomastering

  • Hind Kadiri,
  • Serguei Kostcheev,
  • Daniel Turover,
  • Rafael Salas-Montiel,
  • Komla Nomenyo,
  • Anisha Gokarna and
  • Gilles Lerondel

Beilstein J. Nanotechnol. 2014, 5, 1203–1209, doi:10.3762/bjnano.5.132

Graphical Abstract
  • analysis were used to characterize the morphology of the ordered surfaces. Finally, the production of silicon molds is demonstrated by using the beads as a template for dry etching. Keywords: assisted self-organization; dislocations; patterning; polystyrene beads; single crystal; Introduction The
  • and the nature of the solvent were the two important parameters which affected the self-organization of the beads. The optimisation of these parameters allows us to produce large-scale colloidal 2D monocrystals. Another problem addressed in this study was the presence of dislocations in these PS bead
  • patterns. By using patterned silicon substrates, we were able to minimize the presence of these dislocations resulting in the formation of single crystal structures of PS beads on the entire pre-patterned area, which is scalable depending on the technique used for pre-patterning. Results and Discussion
PDF
Album
Full Research Paper
Published 04 Aug 2014

Scale effects of nanomechanical properties and deformation behavior of Au nanoparticle and thin film using depth sensing nanoindentation

  • Dave Maharaj and
  • Bharat Bhushan

Beilstein J. Nanotechnol. 2014, 5, 822–836, doi:10.3762/bjnano.5.94

Graphical Abstract
  • the hard substrate limits the movement of dislocations. Large strain gradients observed in the ISE also contribute to the material hardness. Scale dependence is also seen in studies of various micro/nano-objects. Enhanced mechanical properties were observed in nano-objects [18][19][20][21][22][23
  • strength or hardness seen with nano-objects has been explained by the dislocation starvation model or the Hall–Petch effect for single crystalline and polycrystalline nano-objects, respectively. In the dislocation starvation model, the absence of dislocations in the interior of the nano-object does not
  • disrupt the regular atomic arrangements in the lattice planes, the so called dislocations. Figure 1 shows for a polycrystalline material, as an example, dislocations in the grain originating from the grain boundary and the grain interior, from a multiplication of existing dislocations during loading or
PDF
Album
Full Research Paper
Published 11 Jun 2014

Nanoscale patterning of a self-assembled monolayer by modification of the molecule–substrate bond

  • Cai Shen and
  • Manfred Buck

Beilstein J. Nanotechnol. 2014, 5, 258–267, doi:10.3762/bjnano.5.28

Graphical Abstract
  • additional steps that emerge during the electrodeposition are identical in height to the 2.5 Å of the Au steps present on the native substrate, thus, strongly suggesting that the Cu-UPD gives rise to dislocations in the Au surface. The tensile stress introduced by the Cu-UPD [40][41] adds to the stress
  • for a small point-shaped damage dislocations in the substrate occur rarely (none in Figure 2, one in Figure 3 intersecting the encircled island in the lower half of image (e)) the more extensive damage of the SAM by writing continuous lines (here in the form of letters) gives rise to a substantial
  • number of substrate dislocations. This can be rationalized by considering that at least the topmost Au layer is affected, which includes the removal of Au atoms together with thiol molecules. Conversion of UPD pattern into binary SAM structure The SAM modified by the UPD pattern corresponds to a latent
PDF
Album
Supp Info
Full Research Paper
Published 10 Mar 2014

Challenges in realizing ultraflat materials surfaces

  • Takashi Yatsui,
  • Wataru Nomura,
  • Fabrice Stehlin,
  • Olivier Soppera,
  • Makoto Naruse and
  • Motoichi Ohtsu

Beilstein J. Nanotechnol. 2013, 4, 875–885, doi:10.3762/bjnano.4.99

Graphical Abstract
  • substrate can be a serious problem, because substrates with large Ra values induce defects or dislocations in the deposited active layer [4]. Diamond is a promising material for future power devices because of its many excellent characteristics including high values for hardness and thermal conductivity
PDF
Album
Review
Published 11 Dec 2013

Deformation-induced grain growth and twinning in nanocrystalline palladium thin films

  • Aaron Kobler,
  • Jochen Lohmiller,
  • Jonathan Schäfer,
  • Michael Kerber,
  • Anna Castrup,
  • Ankush Kashiwar,
  • Patric A. Gruber,
  • Karsten Albe,
  • Horst Hahn and
  • Christian Kübel

Beilstein J. Nanotechnol. 2013, 4, 554–566, doi:10.3762/bjnano.4.64

Graphical Abstract
  • are under investigation for a number of years, there still is an ongoing debate on the deformation mechanisms active in these materials. Discussed are grain boundary sliding, grain rotation, emission and annihilation of dislocations at grain boundaries, intragranular dislocation glide resulting in
  • increasing strain (Figure 7a,b). In the slices through representative grains at different stages of the deformation, it is shown that twin boundaries (highlighted in red) disappear from the microstructure. This occurs by nucleation of partial dislocations at twin boundaries and their successive motion (not
  • shown). In contrast, samples with an initially defect free grain interior showed an increase of the twin boundary density during straining (Figure 7c,d). Twins nucleate at the grain boundaries under an applied stress by emission of partial dislocations, which lead to stacking faults and eventually twin
PDF
Album
Supp Info
Full Research Paper
Published 24 Sep 2013

Plasticity of nanocrystalline alloys with chemical order: on the strength and ductility of nanocrystalline Ni–Fe

  • Jonathan Schäfer and
  • Karsten Albe

Beilstein J. Nanotechnol. 2013, 4, 542–553, doi:10.3762/bjnano.4.63

Graphical Abstract
  • dislocations [3][4]. The experimental realization of a nanocrystalline (nc) microstructure of an ordered alloy, however, strongly depends on the route of preparation. For electrodeposited nc Ni–Fe alloys (up to 28% Fe) a solid solution with no chemical order was observed [5]. In Ni3Al, a partially ordered
  • investigate, e.g., the nucleation of dislocations from surfaces [13] or at GBs [14]. Furthermore, the mechanical response of intermetallic nanostructures such as nanowires has been studied by MD [15]. For understanding the atomistic processes that are carrying and controlling plastic deformation in nc
  • microstructure was done by a novel algorithm, which allows for the extraction and analysis of dislocations from simulation data in a fully automated way [26]. The local atomic volume of each atom was calculated by means of the Voronoi tessellation method [27]. We define the free volume of the GB atoms as the
PDF
Album
Full Research Paper
Published 19 Sep 2013

High-resolution electrical and chemical characterization of nm-scale organic and inorganic devices

  • Pierre Eyben

Beilstein J. Nanotechnol. 2013, 4, 318–319, doi:10.3762/bjnano.4.35

Graphical Abstract
  • , threading dislocations, and microtwins that affect the diffusion of dopants and the material mobility (due to scattering). When growth is performed in narrow trenches, dislocations are trapped within the confined volume (aspect-ratio trapping) and, theoretically, defect-free layers can be obtained. However
PDF
Editorial
Published 16 May 2013

Plasticity of Cu nanoparticles: Dislocation-dendrite-induced strain hardening and a limit for displacive plasticity

  • Antti Tolvanen and
  • Karsten Albe

Beilstein J. Nanotechnol. 2013, 4, 173–179, doi:10.3762/bjnano.4.17

Graphical Abstract
  • is extruded from a hole of 1.1–1.6 nm radius under athermal conditions. Simultaneous nucleation of partial dislocations at the extrusion orifice leads to the formation of dislocation dendrites in the particle causing strain hardening and high flow stress of the material. As the extrusion orifice
  • movement, multiplication, and entanglement of mobile dislocations. As system size decreases, the relative surface (nanoparticle) or interface area (nanograined material) increases, and nucleation or annihilation of dislocations at surfaces or interfaces becomes a dominant factor since conventional
  • the intersection of the orifice and the surface where the dislocations are nucleated. Before the onset of plasticity, the system goes through small rotations to accommodate the stresses changing slightly the initial lattice orientation. Qualitatively, in the displacive regime, the deformation follows
PDF
Album
Supp Info
Full Research Paper
Published 07 Mar 2013

Catalytic activity of nanostructured Au: Scale effects versus bimetallic/bifunctional effects in low-temperature CO oxidation on nanoporous Au

  • Lu-Cun Wang,
  • Yi Zhong,
  • Haijun Jin,
  • Daniel Widmann,
  • Jörg Weissmüller and
  • R. Jürgen Behm

Beilstein J. Nanotechnol. 2013, 4, 111–128, doi:10.3762/bjnano.4.13

Graphical Abstract
  • , indicate that the crystallites are significantly strained, possibly due to a large density of lattice dislocations. On NPG(Ag)-1, the diffraction peaks are significantly sharper, indicating a lower defect density. This goes along with a significantly lower specific surface area of sample NPG(Ag)-1 as
PDF
Album
Supp Info
Full Research Paper
Published 19 Feb 2013

Assessing the plasmonics of gold nano-triangles with higher order laser modes

  • Laura E. Hennemann,
  • Andreas Kolloch,
  • Andreas Kern,
  • Josip Mihaljevic,
  • Johannes Boneberg,
  • Paul Leiderer,
  • Alfred J. Meixner and
  • Dai Zhang

Beilstein J. Nanotechnol. 2012, 3, 674–683, doi:10.3762/bjnano.3.77

Graphical Abstract
  • triangles interrupted by slightly larger gold structures. The latter result from dislocations within the self-assembled monolayer of the polystyrene spheres [9][10]. 2. Confocal luminescence patterns of gold Fischer patterns We performed confocal scanning images of six Fischer patterns of different triangle
PDF
Album
Supp Info
Full Research Paper
Published 04 Oct 2012

Synthesis and electrical characterization of intrinsic and in situ doped Si nanowires using a novel precursor

  • Wolfgang Molnar,
  • Alois Lugstein,
  • Tomasz Wojcik,
  • Peter Pongratz,
  • Norbert Auner,
  • Christian Bauch and
  • Emmerich Bertagnolli

Beilstein J. Nanotechnol. 2012, 3, 564–569, doi:10.3762/bjnano.3.65

Graphical Abstract
  • pattern (inset in Figure 2b) prove that the growth axis is [111], and previous work on Si-NWs grown with SiH4 revealed, vertical {112} facets [32]. The NWs are usually free of dislocations and stacking faults and are covered by a very thin oxide layer. As already mentioned above, the addition of B2H6
PDF
Album
Full Research Paper
Published 31 Jul 2012

Imaging ultra thin layers with helium ion microscopy: Utilizing the channeling contrast mechanism

  • Gregor Hlawacek,
  • Vasilisa Veligura,
  • Stefan Lorbek,
  • Tijs F. Mocking,
  • Antony George,
  • Raoul van Gastel,
  • Harold J. W. Zandvliet and
  • Bene Poelsema

Beilstein J. Nanotechnol. 2012, 3, 507–512, doi:10.3762/bjnano.3.58

Graphical Abstract
  • , light adlayers on heavy substrates can be imaged. We emphasize that this contrast mechanism is purely based on changes in the crystallography of the sample. Apart from the detection of ultrathin adlayers, this mechanism therefore also has the potential to reveal crystal defects, such as dislocations or
PDF
Album
Full Research Paper
Published 12 Jul 2012

Dipole-driven self-organization of zwitterionic molecules on alkali halide surfaces

  • Laurent Nony,
  • Franck Bocquet,
  • Franck Para,
  • Frédéric Chérioux,
  • Eric Duverger,
  • Frank Palmino,
  • Vincent Luzet and
  • Christian Loppacher

Beilstein J. Nanotechnol. 2012, 3, 285–293, doi:10.3762/bjnano.3.32

Graphical Abstract
  • dislocations, such that only small areas with a more or less uniform height can be observed (not shown). Along the long molecular axes (i.e., the direction), only every second molecular protrusion could act as an anchoring point. As depicted in Figure 5c for KBr, this does not change the shape, with a single
PDF
Album
Full Research Paper
Published 27 Mar 2012

Template-assisted formation of microsized nanocrystalline CeO2 tubes and their catalytic performance in the carboxylation of methanol

  • Jörg J. Schneider,
  • Meike Naumann,
  • Christian Schäfer,
  • Armin Brandner,
  • Heiko J. Hofmann and
  • Peter Claus

Beilstein J. Nanotechnol. 2011, 2, 776–784, doi:10.3762/bjnano.2.86

Graphical Abstract
  • the PMMA polymer template and thus a denser material deposition of the ceria sol. Photoluminescence (PL) measurements (Figure 10, excitation wavelength 325 nm) reveal a maximum at 415 nm [23]. The strong emission of CeO2 at this wavelength is related to abundant defects such as dislocations, which are
PDF
Album
Full Research Paper
Published 30 Nov 2011

The atomic force microscope as a mechano–electrochemical pen

  • Christian Obermair,
  • Andreas Wagner and
  • Thomas Schimmel

Beilstein J. Nanotechnol. 2011, 2, 659–664, doi:10.3762/bjnano.2.70

Graphical Abstract
  • would exhibit a high density of defects (steps, kinks, dislocations, etc.). In our experiments, metal deposition was observed selectively only at the positions were the AFM tip was scanned. Finally, tip-induced defects on the gold surface cannot explain the effects of repassivation and depassivation of
PDF
Album
Full Research Paper
Published 04 Oct 2011

Investigation on structural, thermal, optical and sensing properties of meta-stable hexagonal MoO3 nanocrystals of one dimensional structure

  • Angamuthuraj Chithambararaj and
  • Arumugam Chandra Bose

Beilstein J. Nanotechnol. 2011, 2, 585–592, doi:10.3762/bjnano.2.62

Graphical Abstract
  • factor (0.9), λ is the wavelength of Cu Kα1 radiation (1.5406 Å), and θhkl is the Bragg diffraction angle. The crystallite size was estimated and found to be 51 nm. Although the size of the crystallite is in the nanometer range, significant structural defects such as dislocations, staking faults, twin
PDF
Album
Full Research Paper
Published 14 Sep 2011

Plasmonic nanostructures fabricated using nanosphere-lithography, soft-lithography and plasma etching

  • Manuel R. Gonçalves,
  • Taron Makaryan,
  • Fabian Enderle,
  • Stefan Wiedemann,
  • Alfred Plettl,
  • Othmar Marti and
  • Paul Ziemann

Beilstein J. Nanotechnol. 2011, 2, 448–458, doi:10.3762/bjnano.2.49

Graphical Abstract
  • areal extents up to 1 cm2. The number of vacancies and dislocations of the colloidal crystal increased as the size of the beads decreased. For beads of 3 μm size, single crystals of several mm2 were usually obtained. The evaporation of the water and full crystallization takes up to 6 h. Epoxy resin
PDF
Album
Full Research Paper
Published 16 Aug 2011

Structure, morphology, and magnetic properties of Fe nanoparticles deposited onto single-crystalline surfaces

  • Armin Kleibert,
  • Wolfgang Rosellen,
  • Mathias Getzlaff and
  • Joachim Bansmann

Beilstein J. Nanotechnol. 2011, 2, 47–56, doi:10.3762/bjnano.2.6

Graphical Abstract
  • particular, it turns out that upon impact the particles are temporarily disordered. The subsequent recrystallization happens on a ps time scale and may result in partial or full epitaxy of the particles. Thereby, the alignment with the substrate is achieved by a thermally activated ejection of dislocations
  • temperature. Our room temperature experiments show stable particle properties over periods of several hours. Thus, we conclude that the kinetic barriers for further relaxation are relatively high, and dislocations are effectively trapped in those particles which are not aligned with the substrate. Note that
  • dislocations locally reduce the symmetry in the crystal lattice and, thus, the MD simulations together with the random orientation found for larger particles (D > 4 nm) may provide an alternative explanation for the strongly enlarged orbital moments presented in Figure 2f. Namely, trapped dislocations might
PDF
Album
Full Research Paper
Published 21 Jan 2011

Magnetic coupling mechanisms in particle/thin film composite systems

  • Giovanni A. Badini Confalonieri,
  • Philipp Szary,
  • Durgamadhab Mishra,
  • Maria J. Benitez,
  • Mathias Feyen,
  • An Hui Lu,
  • Leonardo Agudo,
  • Gunther Eggeler,
  • Oleg Petracic and
  • Hartmut Zabel

Beilstein J. Nanotechnol. 2010, 1, 101–107, doi:10.3762/bjnano.1.12

Graphical Abstract
  • , such as the presence of regions with two overlapping layers, missing particles (voids), and dislocations separating domains of hexagonal order. Aside from the presence of local defects, the spin-coating technique has proven to be able to produce long range hexagonal order over areas of 10 × 10 mm2 with
  • schematically depicted in the inset of Figure 5. The Co film does not cover all NPs equally, but only the top layer of NPs. In a 'monolayer' of NPs (that means one layer of particles on average) there exist not only holes and dislocations in the array but also areas with a second layer (see Figure 1). Hence
PDF
Album
Full Research Paper
Published 01 Dec 2010
Other Beilstein-Institut Open Science Activities