Hydrogen-induced plasticity in nanoporous palladium

• Markus Gößler,
• Eva-Maria Steyskal,
• Markus Stütz,
• Norbert Enzinger and
• Roland Würschum

Beilstein J. Nanotechnol. 2018, 9, 3013–3024, doi:10.3762/bjnano.9.280

• above-mentioned tunable properties in nanoporous metals. The deformation mechanism in such structures has been discussed in detail. Since nanoporous materials exhibit high surface-to-volume ratios, moving dislocations may escape crystals via the surface, which may lead to a scenario of dislocation

• at low strains in npAu. Despite the local dislocation activity in the ligaments, macroscopic plasticity, involving dislocations travelling larger distances in the network structure, is hard to achieve in nanoporous metals [15]. Plastic deformation in npPd has not been the subject of experimental

• proceed incoherently, inducing dislocations to reduce internal stresses [34]. A coherent phase transition on the other hand involves the occurrence of internal stresses due to spatial variations of the lattice spacing, while no dislocations are induced. Therefore, particles must be sufficiently small in

Low cost tips for tip-enhanced Raman spectroscopy fabricated by two-step electrochemical etching of 125 µm diameter gold wires

• Antonino Foti,
• Francesco Barreca,
• Enza Fazio,
• Cristiano D’Andrea,
• Paolo Matteini,
• Onofrio Maria Maragò and
• Pietro Giuseppe Gucciardi

Beilstein J. Nanotechnol. 2018, 9, 2718–2729, doi:10.3762/bjnano.9.254

• sections of the gold wire supplied by the producer, we end up with very rough tips (Figure 5), even in the presence of “fresh” solutions. Rough surfaces have been explained [46] with the presence of dislocations and grains in the 100–500 nm scale (consequence of the wire production process), in which the

Metal-free catalysis based on nitrogen-doped carbon nanomaterials: a photoelectron spectroscopy point of view

• Mattia Scardamaglia and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2018, 9, 2015–2031, doi:10.3762/bjnano.9.191

• . Indeed, the graphitic network can be easily modified by the introduction of heteroatoms, functional groups or defects, such as dislocations, vacancies or edges [25][34][35]. They act as active sites for electron localization or they are useful to anchor metal clusters or foreign molecules that will, in

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

• dislocations lines (often also called “solitons” or “kinks”), which is required for the overall depinning of the island and thus defines the static friction [70]. An important influence of the edge was also found for GNRs sliding on gold (see subsection “Manipulation of graphene nanoribbons on gold” below

• simulations [100]. According to MD simulations, a critical length scale exists for nanoparticles above which dislocations are formed at the interface and sliding is governed by the motion of these dislocations. This ultimately marks the transition from sublinear to linear scaling between friction and area

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

• active and are thus highly preferable as a catalyst surface over the relatively inert MoS2 basal plane [27]. Figure 4c shows the atomic structure of the MoS2 NSs with some edge dislocations (labelled as “T”) along the c-axis. Moreover, the interplanar distances are ca. 0.62 and ca. 0.30 nm, corresponding

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

• dislocations in the LED structure were blocked, thus enhancing the general luminous efficiency by approximately 23% [15]. Cates et al. adopted laser etching to produce a repeated microstructure on the emitting surface of a yttrium aluminum perovskite scintillation crystal activated by cerium (formula YAlO3:Ce

Fatigue crack growth characteristics of Fe and Ni under cyclic loading using a quasi-continuum method

• Ren-Zheng Qiu,
• Yi-Chen Lin and
• Te-Hua Fang

Beilstein J. Nanotechnol. 2018, 9, 1000–1014, doi:10.3762/bjnano.9.93

• at any orientation, the slip dislocation observed in the materials considerably affects the release of stress. Keywords: dislocations; fatigue crack growth; materials treatment effects; mechanics; shear stress; Introduction When materials undergo cyclic loading, the growth of cracks in the material

• distance of the sample reached 6 nm (Figure 14c), the crack tip did not expand in the same manner as that observed under the cyclic loading process of mode I. Instead, the crack tip only generated dislocations, and the position of the opening was slightly pulled up. For the reverse shear process during the

• of Fe tended to be steady after the fourth cyclic loading (Figure 15). During the first cyclic loading (Figure 16a–c), Figure 16a shows that mixed dislocations extended from the crack tip to the internal structure. This observation is different from the case of Ni generating regular and clear slip

Blister formation during graphite surface oxidation by Hummers’ method

• Olga V. Sinitsyna,
• Georgy B. Meshkov,
• Anastasija V. Grigorieva,
• Alexander A. Antonov,
• Inna G. Grigorieva and
• Igor V. Yaminsky

Beilstein J. Nanotechnol. 2018, 9, 407–414, doi:10.3762/bjnano.9.40

• surface. Surprisingly, the destruction of the sp2-lattice was not detected in the ordered regions. We suggest that the reagent diffusion under the basal plane surface occurred through the cleavage steps and dislocations with the Burgers vector parallel to the c-axis in graphite. Keywords: atomic force

• dislocations with Burgers vector perpendicular to the basal plane. In the second case, atomic steps are located mainly below the surface. The deeper an atomic step lies, the smoother the relief on the surface. In our AFM experiments, we observed surface height changes for the dislocation lines located at a

• depth of up to 4 nm. The edge dislocations originate in the form of loops during the synthesis of the HAPG. The cleavage steps are often straight and form along the cleavage direction. The number of cleavage steps is probably related to the presence of defects binding the carbon layers together. The

Al₂O₃/TiO₂ inverse opals from electrosprayed self-assembled templates

• Arnau Coll,
• Sandra Bermejo,
• David Hernández and
• Luís Castañer

Beilstein J. Nanotechnol. 2018, 9, 216–223, doi:10.3762/bjnano.9.23

• dislocations in between, and no cracks were present. Atomic layer deposition The second step of our fabrication procedure uses the polystyrene structure shown in Figure 2 as a template in which other suitable materials can be deposited. In our case, alumina was first deposited as it is a material that can be

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

• threading dislocations [32][33][34] followed by transition to three-dimensional growth of nanoislands [33][35]. The phenomenon of the Si solubility limit elevation in GaN NWs is usually explained again through effective stress relaxation due to the large surface area of these nanostructures. This work is

Nematic topological defects positionally controlled by geometry and external fields

• Pavlo Kurioz,
• Marko Kralj,
• Bryce S. Murray,
• Charles Rosenblatt and
• Samo Kralj

Beilstein J. Nanotechnol. 2018, 9, 109–118, doi:10.3762/bjnano.9.13

• volume is (at least partially) replaced by the volume of the NP, thereby reducing the overall energy. It has been shown that lattices of orientational (disclinations) [11][12] and translational (dislocations) [9] defects can readily trap such NPs. Furthermore, it was demonstrated that line defects could

Nanoprofilometry study of focal conic domain structures in a liquid crystalline free surface

• Anna N. Bagdinova,
• Evgeny I. Demikhov,
• Nataliya G. Borisenko and
• Sergei M. Tolokonnikov

Beilstein J. Nanotechnol. 2017, 8, 2544–2551, doi:10.3762/bjnano.8.254

• barrier and the display can lose orientation over a large area, initiating the formation of FCDs inside of the liquid crystalline layer. In the case of inner boundary formation due to dislocations, the nanoprofilometer technique can be applied for structure observation. The FCD structures can be compared

Molecular dynamics simulations of nanoindentation and scratch in Cu grain boundaries

• Shih-Wei Liang,
• Ren-Zheng Qiu and
• Te-Hua Fang

Beilstein J. Nanotechnol. 2017, 8, 2283–2295, doi:10.3762/bjnano.8.228

• scratch conditions were studied by molecular dynamics (MD) simulations. The type of grain boundary is the main factor in the control of the substrate atoms with respect to the size of dislocations since the existence of the grain boundary itself restricts the movement associated with dislocations. In this

• size of 8 nm [10]. The authors found that the dislocations piled up at the grain boundary such that the grain boundary supports the strong barriers at large grain sizes [10]. Figure 11 shows the von Mises stress diagrams of the vertical grain boundary at different angles (θ = 10–40°) upon an

Stable Au–C bonds to the substrate for fullerene-based nanostructures

• Taras Chutora,
• Jesús Redondo,
• Bruno de la Torre,
• Martin Švec,
• Pavel Jelínek and
• Héctor Vázquez

Beilstein J. Nanotechnol. 2017, 8, 1073–1079, doi:10.3762/bjnano.8.109

• Shockley partial dislocations of the Au bulk [38][39]. The faulty structure of the elbow site makes it a favorable nucleation site for the functionalized molecules to bind. STM images also show the presence of dimer structures bound at the elbow sites (indicated by blue circles). We attribute these

Diffusion and surface alloying of gradient nanostructured metals

• Zhenbo Wang and
• Ke Lu

Beilstein J. Nanotechnol. 2017, 8, 547–560, doi:10.3762/bjnano.8.59

• the grain sizes are usually in the sub-micrometer scale (>200 nm) and numerous dislocations exist in grains [28]. The microstructural observations revealed that the GNS layers on metals processed by surface mechanical attrition treatments (SMAT) are porosity-free, and the mean grain sizes are on the

• dislocations) are difficult to be identified in GNS or SPD metals, it is argued that the GB diffusion might also be accelerated by GB thickening, resulting from either the GB prewetting (premelting) or the pseudo-partial GB wetting during sample preparation [46][47][48][49]. For example, a Zn-rich wetting

• misorientation angle and forms a sharp cusp only several degrees in deviation around the corresponding angle of the coherent TBs, i.e., 70.5° of twin/matrix with [110] symmetric tilt boundary in Cu [54]. In the GNS layer, various dislocations are accumulated at TBs, resulting in a significant increment of

Formation and shape-control of hierarchical cobalt nanostructures using quaternary ammonium salts in aqueous media

• Ruchi Deshmukh,
• Anurag Mehra and
• Rochish Thaokar

Beilstein J. Nanotechnol. 2017, 8, 494–505, doi:10.3762/bjnano.8.53

• by using NH4OH during electrodeposition [26]. The growth of these unique cone nanostructures is initiated by screw dislocations. In this study, interesting spindles with peculiar conical edges are synthesized that can be, in principle, surface-functionalized for various applications. A magnified

Annealing-induced recovery of indents in thin Au(Fe) bilayer films

• Anna Kosinova,
• Ruth Schwaiger,
• Leonid Klinger and
• Eugen Rabkin

Beilstein J. Nanotechnol. 2016, 7, 2088–2099, doi:10.3762/bjnano.7.199

• processes in the material controlled by capillary forces [10][11] or the interaction of defects [12]. The healing capability of defects was recently demonstrated for Au [13] and Fe [14] nanoparticles. It was shown that the controlled injection of dislocations into single-crystalline faceted metal

• dislocations climb, surface diffusion, and grain boundary diffusion. It is interesting that reversible formation/annihilation of hillocks at the indented sites upon heating/cooling was demonstrated in bulk and thin film samples of shape memory NiTi alloy [28]. This was achieved by planarizing the as-produced

• for several indents. It should be noted that the arrangement of the dislocations shown does not represent the crystallography of the sample, but rather symbolizes the high dislocation density accounting for mass conservation and that is typical of indentation. The envisioned process should occur for

A new approach to grain boundary engineering for nanocrystalline materials

• Shigeaki Kobayashi,
• Sadahiro Tsurekawa and
• Tadao Watanabe

Beilstein J. Nanotechnol. 2016, 7, 1829–1849, doi:10.3762/bjnano.7.176

• structure, and conventional grain size range. It is evident that the much higher strength of nanocrystalline materials compared to ordinary polycrystals originates from the extensive interaction between grain boundaries and dislocations. On the other hand, poor ductility and severe brittleness of

• polycrystalline molybdenum. The generated dislocations can transfer or pass across low-angle boundaries more easily than random boundaries composed of more complicated tilt and twist components at room temperature [72]. It is evident that the grain boundary character can strongly affect the hardness at individual

• character distribution (TJCD) also strongly affects the hardness of submicrometer-grained nickel specimens as well as GBCD. This is probably because the interaction of crystal dislocations with grain boundaries was found to strongly depend on the boundary character, leading to the passage of them across the

Monolayer graphene/SiC Schottky barrier diodes with improved barrier height uniformity as a sensing platform for the detection of heavy metals

• Ivan Shtepliuk,
• Jens Eriksson,
• Volodymyr Khranovskyy,
• Tihomir Iakimov,
• Anita Lloyd Spetz and
• Rositsa Yakimova

Beilstein J. Nanotechnol. 2016, 7, 1800–1814, doi:10.3762/bjnano.7.173

• ideality parameter for graphene/SiC structures are the homogeneity of the graphene thickness, the quality of the grown interface (defects, pits, dislocations, surface roughness), the type of the grown interface (SiC polytypism, face polarity) and the growth conditions. Indeed, we noticed that the Schottky

Effect of triple junctions on deformation twinning in a nanostructured Cu–Zn alloy: A statistical study using transmission Kikuchi diffraction

• Silu Liu,
• Xiaolong Ma,
• Lingzhen Li,
• Liwen Zhang,
• Patrick W. Trimby,
• Xiaozhou Liao,
• Yusheng Li,
• Yonghao Zhao and
• Yuntian Zhu

Beilstein J. Nanotechnol. 2016, 7, 1501–1506, doi:10.3762/bjnano.7.143

• formation mechanisms [14][19][20][21][22], interactions with dislocations [11][23][24][25][26] and macroscopic strain [10][25][27], due to its extraordinary spatial resolution. However, reliable statistical analysis based on extensive data still seems a grand challenge for HRTEM studies on twinning [28][29

• dislocations produced by severe plastic deformation [32]. The inset shows a corresponding diffraction pattern. The presence of smeared and ring-like diffraction patterns implies lots of nanoscale grains and their low-angle misorientations. This result is consistent with previous reports of copper alloys

• intersects with a triple junction. It has been reported that the area nearby a triple junction would emit or absorb free volumes to promote the emission of partial dislocations [12] and then emitted partial dislocations would induce the growth of stacking faults or twins [14][15]. Therefore, a twin meeting

In situ observation of deformation processes in nanocrystalline face-centered cubic metals

• Aaron Kobler,
• Christian Brandl,
• Horst Hahn and
• Christian Kübel

Beilstein J. Nanotechnol. 2016, 7, 572–580, doi:10.3762/bjnano.7.50

• of mobile and/or sessile dislocations in the grain during the tensile load [40][41][42], which can condense around the boundary and can leave the orange crystallite with reduced defect concentration in the grain upon fracture (see the disorientation to mean orientation plot, Supporting Information

• grains (e.g., white/grey crystallite at the bottom grows with straining). In general, the twin activity correlates with local plastic strain manifested in the structural changes. Since Shockley partial dislocations of the fcc lattice have the same Burgers vectors as the intrinsic crystallographic

• structure elements of twin (Σ3) boundaries [44], the twin motion indicates the operation of Shockley partial dislocations entering the grain from the boundary or moving along the preexisting twin planes. The twin activity associated with heterogeneous distribution of the plastic strain indicates the

Hydration of magnesia cubes: a helium ion microscopy study

• Ruth Schwaiger,
• Johannes Schneider,
• Gilles R. Bourret and
• Oliver Diwald

Beilstein J. Nanotechnol. 2016, 7, 302–309, doi:10.3762/bjnano.7.28

• crystalline organic polymers such as polyimides that were grown by hydrothermal crystallization [37][38]. Independent of the chemical composition, nucleation is initiated at screw dislocations. Further crystallization proceeds non classically due to a strong growth anisotropy and different attachment energies

Plasticity-mediated collapse and recrystallization in hollow copper nanowires: a molecular dynamics simulation

• Amlan Dutta,
• Arup Kumar Raychaudhuri and
• Tanusri Saha-Dasgupta

Beilstein J. Nanotechnol. 2016, 7, 228–235, doi:10.3762/bjnano.7.21

• , which would involve much longer time scales as compared to the plasticity-based mechanism. Keywords: dislocations; molecular dynamics; nanowire; thermal stability; Introduction Nanomaterials, as compared to bulk, are associated with large surfaces and interfaces with respect to their volume. The

• system. The resolved shear load can thereby exceed the critical limit for producing the Shockley dislocations. The calculated shear-strain map indicates that the partial dislocations nucleate at the inner surface and propagate towards the outer periphery, thereby leaving behind trails of stacking faults

• the stacking faults get eliminated at this stage, and the final structure consists of only a few twin boundaries as shown in the inset of Figure 3a. As already mentioned, recrystallization of the residual disordered atoms prompts the formation of [112]/6-type partial dislocations at the boundaries of

Dependence of lattice strain relaxation, absorbance, and sheet resistance on thickness in textured ZnO@B transparent conductive oxide for thin-film solar cell applications

• Kuang-Yang Kou,
• Yu-En Huang,
• Chien-Hsun Chen and
• Shih-Wei Feng

Beilstein J. Nanotechnol. 2016, 7, 75–80, doi:10.3762/bjnano.7.9

• as a function of thickness, t: compressive strain for t < 5.5 nm, released compressive strain due to generation of misfit dislocations for 5.5 nm < t < 200 nm, tensile strain due to thermal stress for 200 nm < t < 500 nm, and residual tensile strain relaxed by microcrack formation for t > 500 nm [10

Simulation of thermal stress and buckling instability in Si/Ge and Ge/Si core/shell nanowires

• Suvankar Das,
• Amitava Moitra,
• Mishreyee Bhattacharya and
• Amlan Dutta

Beilstein J. Nanotechnol. 2015, 6, 1970–1977, doi:10.3762/bjnano.6.201

• misfit dislocations is significant only at larger diameters [1][19][20]. For constructing the core/shell wires, a strategy similar to that used by Liu et al. [16] has been employed. Although their analyses were for the wires of hexagonal cross-sections, the present investigations are based on the