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Search for "clusters" in Full Text gives 412 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.

Analysis of catalyst surface wetting: the early stage of epitaxial germanium nanowire growth

  • Owen C. Ernst,
  • Felix Lange,
  • David Uebel,
  • Thomas Teubner and
  • Torsten Boeck

Beilstein J. Nanotechnol. 2020, 11, 1371–1380, doi:10.3762/bjnano.11.121

Graphical Abstract
  • are fully understood yet, especially regarding metallic fluids, it is clear that the formation of nanometre-sized particles, droplets, and clusters as well as their movement are strongly linked to their wetting behaviour. For this reason, the thermodynamic stability of thin metal layers (0.1–100 nm
  • dewetting process, since the name of the resulting structures are nanoparticles or clusters but rarely droplets. Nevertheless, the origin of these structures from fluid-like states offers the opportunity for novel bottom-up techniques to produce precursor materials for functional materials, such as
  • electron microscopy (TEM) images of gold particles formed on a silicon substrate at room temperature. Small gold clusters (<10 nm) are also seen between the droplets. Growth of germanium nanowires Figure 4 shows images of the resulting gold droplets on various substrates and the results after deposition of
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Published 09 Sep 2020

Atomic defect classification of the H–Si(100) surface through multi-mode scanning probe microscopy

  • Jeremiah Croshaw,
  • Thomas Dienel,
  • Taleana Huff and
  • Robert Wolkow

Beilstein J. Nanotechnol. 2020, 11, 1346–1360, doi:10.3762/bjnano.11.119

Graphical Abstract
  • observed in raised Si clusters of various sizes as discussed with Supporting Information File 1, Figure S9. The raised nature of the silyl group has implications for all the performed constant height analysis; in constant height STM (Figure 2i-3) it dominates the current as it is closer to the tip, in STHM
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Published 07 Sep 2020

Growth of a self-assembled monolayer decoupled from the substrate: nucleation on-command using buffer layers

  • Robby Reynaerts,
  • Kunal S. Mali and
  • Steven De Feyter

Beilstein J. Nanotechnol. 2020, 11, 1291–1302, doi:10.3762/bjnano.11.113

Graphical Abstract
  • symmetry of the underlying alkane layer [27]. Buffer layers of tetratriacontane [25] and tridecylamine [31] were used to template the self-assembly of copper phthalocyanine. Room temperature STM measurements revealed that the adsorption as well as the diffusion of clusters of CuPc molecules was strongly
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Published 01 Sep 2020

High permittivity, breakdown strength, and energy storage density of polythiophene-encapsulated BaTiO3 nanoparticles

  • Adnanullah Khan,
  • Amir Habib and
  • Adeel Afzal

Beilstein J. Nanotechnol. 2020, 11, 1190–1197, doi:10.3762/bjnano.11.103

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  • of as-prepared BTO nanoparticles. Clusters or agglomerates of nanoparticles can be seen with easily identifiable individual BTO nanoparticles. The size of BTO nanoparticles is in the range of 70–150 nm. In contrast, the core–shell BTO-PTh nanoparticles exhibit uniform surface morphology, as shown in
  • studied using atomic force microscopy, after depositing the samples on quartz wafers. Figure 5 shows the 2D- and 3D-AFM images of BTO, BTO-PTh, and PTh samples along with their surface profiles. The micrographs of BTO nanoparticles show the presence of clusters on the surface. This is in agreement with
  • exhibit irregular surface profile, which confirms the occurrence of sub-micrometer clusters and nanoscale particles on the surface. The permittivity or dielectric constant (ε′), loss tangent (tan δ), dielectric loss (ε″), and ac conductivity (σac) of the synthesized materials are measured as a function of
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Published 10 Aug 2020

Hybridization vs decoupling: influence of an h-BN interlayer on the physical properties of a lander-type molecule on Ni(111)

  • Maximilian Schaal,
  • Takumi Aihara,
  • Marco Gruenewald,
  • Felix Otto,
  • Jari Domke,
  • Roman Forker,
  • Hiroyuki Yoshida and
  • Torsten Fritz

Beilstein J. Nanotechnol. 2020, 11, 1168–1177, doi:10.3762/bjnano.11.101

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  • rubrene on highly oriented pyrolytic graphite (HOPG) [29]. Our interpretation of the optical spectra is further supported by LT-STM measurements (see Supporting Information File 1, Figure S2) which show a completely filled monolayer as well as molecular clusters on top of the first layer. Lateral
  • as clusters of molecules on top of the first DBP layer. The fast Fourier transform (FFT) of that STM image resembles the LEED simulation of the molecular lattice (considering eight symmetry equivalent domains only), which supports our structural model. Valence band structure and work function change
  • large-area STM images (Supporting Information File 1, Figure S2), which confirm a close-packed DBP wetting layer as well as DBP clusters on top for a nominal film thickness of about 1.6 MLE. Hence, there is little discrepancy between 1 MLE, defined via DRS, and a fully covered substrate surface
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Published 04 Aug 2020

Scanning tunneling microscopy and spectroscopy of rubrene on clean and graphene-covered metal surfaces

  • Karl Rothe,
  • Alexander Mehler,
  • Nicolas Néel and
  • Jörg Kröger

Beilstein J. Nanotechnol. 2020, 11, 1157–1167, doi:10.3762/bjnano.11.100

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  • vibronic properties of C42H28 consistently reflect the progressive reduction of the molecule–substrate hybridization. Separate C42H28 clusters are observed on Pt(111) as well as broad molecular resonances. On Au(111) and graphene-covered Pt(111) compact molecular islands with similar unit cells of the
  • expected to be well decoupled from the metal substrate. After adsorption of C42H28 on Pt(111) scanning tunneling microscopy (STM) images reveal the occurrence of separate molecular clusters and very broad molecular resonances in STS data, which is attributed to an elevated C42H28–Pt interaction. On Au(111
  • clusters of molecules can be discerned on the terrace without evidence for island formation or decoration of substrate step edges. These observations are indicative of an effectively reduced surface diffusion after adsorption, which lowers the mobility of adsorbed molecules and, thus, the formation of
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Published 03 Aug 2020

Straightforward synthesis of gold nanoparticles by adding water to an engineered small dendrimer

  • Sébastien Gottis,
  • Régis Laurent,
  • Vincent Collière and
  • Anne-Marie Caminade

Beilstein J. Nanotechnol. 2020, 11, 1110–1118, doi:10.3762/bjnano.11.95

Graphical Abstract
  • ], platinum [31], ruthenium (in the presence of a reducer) [32], titanium oxo-clusters [33][34] and even from crystals of Au55 gold clusters [35][36]. In most cases, the oxidation state of the metal precursor was either zero (Pd0, Pt0, Au0) or four (TiIVO2 clusters) and no change in the oxidation state
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Letter
Published 28 Jul 2020

Applications of superparamagnetic iron oxide nanoparticles in drug and therapeutic delivery, and biotechnological advancements

  • Maria Suciu,
  • Corina M. Ionescu,
  • Alexandra Ciorita,
  • Septimiu C. Tripon,
  • Dragos Nica,
  • Hani Al-Salami and
  • Lucian Barbu-Tudoran

Beilstein J. Nanotechnol. 2020, 11, 1092–1109, doi:10.3762/bjnano.11.94

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  • of iron oxides in the form of magnetite (Fe3O4) or maghemite (Fe2O3) and are easy to produce through a few well-documented synthesis methods yielding different forms and structures (e.g., round, cubic, hexagonal, clusters, core–shell with gold, silica, polymers, or surfactants). A lot of research is
  • hydrophobic surfaces that induce aggregation and/or the formation of large clusters. When in contact with biological structures, this mechanism provokes capillary clotting and reduces tissue and cellular absorption. To prevent this, nanoparticles are coated with stabilizers, which are added during preparation
  • ]. Recently, SPIONs were observed to be good candidates for photothermal and photodynamic therapy, using near-infrared (700–2000 nm) laser excitation of the nanomaterial. For these therapies, SPIONs are theoretically preferred in larger clusters, although studies have shown that they can yield up to 12 °C
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Published 27 Jul 2020

Wet-spinning of magneto-responsive helical chitosan microfibers

  • Dorothea Brüggemann,
  • Johanna Michel,
  • Naiana Suter,
  • Matheus Grande de Aguiar and
  • Michael Maas

Beilstein J. Nanotechnol. 2020, 11, 991–999, doi:10.3762/bjnano.11.83

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  • nanoparticles agglomerated into clusters inside the fiber matrix. The helical constructs exhibited a diameter of approximately 500 µm with one to two windings per millimeter. Due to their ferromagnetic properties they are easily attracted to a permanent magnet. The results from the tensile testing show that the
  • components into the final product. By subsequent winding we produced helical-shaped fibers with a diameter of approximately 500 µm with one to two windings per millimeter. SEM analysis of wet-spun helical fibers revealed that the IOPs were distributed inside the fiber matrix in larger clusters of 100 nm
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Published 07 Jul 2020

Band tail state related photoluminescence and photoresponse of ZnMgO solid solution nanostructured films

  • Vadim Morari,
  • Aida Pantazi,
  • Nicolai Curmei,
  • Vitalie Postolache,
  • Emil V. Rusu,
  • Marius Enachescu,
  • Ion M. Tiginyanu and
  • Veaceslav V. Ursaki

Beilstein J. Nanotechnol. 2020, 11, 899–910, doi:10.3762/bjnano.11.75

Graphical Abstract
  • to some Zn clusters [43]. A peak at 40.5° marked with an asterisk in Figure 6b was previously found in ZnO nanopowders prepared by the sol–gel method with zinc acetate dihydrate as a precursor [44]. In contrast to this, only peaks related to the Zn0.8Mg0.2O phase are observed in the film annealed at
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Published 12 Jun 2020

Simulations of the 2D self-assembly of tripod-shaped building blocks

  • Łukasz Baran,
  • Wojciech Rżysko and
  • Edyta Słyk

Beilstein J. Nanotechnol. 2020, 11, 884–890, doi:10.3762/bjnano.11.73

Graphical Abstract
  • patterns in the experimental results. The results of our analysis can be found in Figure 3. One can see in Figure 3a that the ordering starts at relatively high temperatures (cf. Figure 2), around T* = 0.62–0.64. Nevertheless, by cooling down the systems we can obtain larger clusters, which is a well-known
  • diffraction pattern, which means that there are a lot of differently oriented clusters in the system. We have very recently shown that this issue can lead to the wrong interpretation of results [39]. One of the possible solutions to that is to take a fragment of the configuration and to the compute
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Published 08 Jun 2020

Nickel nanoparticles supported on a covalent triazine framework as electrocatalyst for oxygen evolution reaction and oxygen reduction reactions

  • Secil Öztürk,
  • Yu-Xuan Xiao,
  • Dennis Dietrich,
  • Beatriz Giesen,
  • Juri Barthel,
  • Jie Ying,
  • Xiao-Yu Yang and
  • Christoph Janiak

Beilstein J. Nanotechnol. 2020, 11, 770–781, doi:10.3762/bjnano.11.62

Graphical Abstract
  • a lower but still measurable Ni count on the seemingly bare CTF shards (point 2). Thus, we conclude that nickel atoms are both found accumulated as larger NP agglomerates on the surface and as smaller nickel clusters. The smaller clusters can either reside on the surface or be included in the CTF
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Published 11 May 2020

Electromigration-induced directional steps towards the formation of single atomic Ag contacts

  • Atasi Chatterjee,
  • Christoph Tegenkamp and
  • Herbert Pfnür

Beilstein J. Nanotechnol. 2020, 11, 680–687, doi:10.3762/bjnano.11.55

Graphical Abstract
  • various types of clusters, and their attachment to the environment to one-dimensional (1D) properties of atomic chains and contacts have been treated in many different studies [1][2][3][4]. However, this topic is not only of pure scientific interest, it is also relevant in the context of the reliable
  • wide Ag contact results in clear unidirectional material transport, as seen by the large clusters preferentially formed on the right-hand side of Figure 1b, appearing as white spots. However, a filamentous structure is always formed on the left-hand side, which neither allows one to identify the exact
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Published 22 Apr 2020

Silver-decorated gel-shell nanobeads: physicochemical characterization and evaluation of antibacterial properties

  • Marta Bartel,
  • Katarzyna Markowska,
  • Marcin Strawski,
  • Krystyna Wolska and
  • Maciej Mazur

Beilstein J. Nanotechnol. 2020, 11, 620–630, doi:10.3762/bjnano.11.49

Graphical Abstract
  • antimicrobial activity of the nanobeads for both strains. One can also notice that for the S. aureus biofilm only small clusters of dead cells, close to the spaces and interruptions in the biofilm, structure are seen. These changes in the structure of the biofilm were not present in the control sample
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Published 14 Apr 2020

Luminescent gold nanoclusters for bioimaging applications

  • Nonappa

Beilstein J. Nanotechnol. 2020, 11, 533–546, doi:10.3762/bjnano.11.42

Graphical Abstract
  • complexes and SCQD-based nanomaterials. To improve the quantum yield and PL, various approaches have been developed including ligand engineering, selective doping to create alloy clusters, aggregation-induced emission, selective etching and self-assembly [48][49][50][51][52][53][54][55][56][57][58]. Ligands
  • the cytoplasm as well as in the nucleus. Muhammed et al. reported brightly NIR-emitting Au23 and Au25 NCs using single-phase and biphasic etching of [Au25(SG)18] (Figure 4B) [87]. The Au23 clusters were selectively conjugated with streptavidin for a specific labeling of cells. Here the strong binding
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Published 30 Mar 2020

DFT calculations of the structure and stability of copper clusters on MoS2

  • Cara-Lena Nies and
  • Michael Nolan

Beilstein J. Nanotechnol. 2020, 11, 391–406, doi:10.3762/bjnano.11.30

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  • vacancy on the adsorption energy and geometry of single Cu adatoms and the Cu4 clusters. The results of this investigation show that the stability of small Cun clusters on a MoS2 ML is driven mainly by Cu–Cu interactions and not dependent on whether the cluster is 2D or 3D. Further, the density-of-states
  • , compared to the various 2D structures. While site 1 continued to be less favourable than sites 2 and 3 for the 2D configurations, for the 3D adsorption mode this difference disappears, with similar binding energies for all sites, suggesting that once 3D clusters begin to form on MoS2 the binding energy is
  • (2D) and two configurations are 3D nanoclusters. For the flat adsorption structures, the four Cu atoms are adsorbed in a linear configuration, with Cu–Cu distances of around 3.2 Å, depending on the adsorption site, or in a 4-membered flat structure. In the 3D clusters, one configuration is a rhombus
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Published 26 Feb 2020

Formation of nanoripples on ZnO flat substrates and nanorods by gas cluster ion bombardment

  • Xiaomei Zeng,
  • Vasiliy Pelenovich,
  • Bin Xing,
  • Rakhim Rakhimov,
  • Wenbin Zuo,
  • Alexander Tolstogouzov,
  • Chuansheng Liu,
  • Dejun Fu and
  • Xiangheng Xiao

Beilstein J. Nanotechnol. 2020, 11, 383–390, doi:10.3762/bjnano.11.29

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  • and ion fluence were 10 kV and 4 × 1016 clusters/cm2, respectively. Scratches and pits of 50–100 nm in size and 5 nm in depth are visible on the substrate surface before irradiation (Figure 2a and Figure 3a). After irradiation at θ = 0° the scratches and pits disappeared and features ca. 10 nm in size
  • homogeneously dispersed all over the surface formed (Figure 2b and Figure 3b). These surface features can exhibit overlapped craters formed after collisions of the accelerated clusters with the surface. The surface roughness after normal cluster irradiation slightly decreases from initial 0.8 nm to 0.6 nm
  • developed and wavelength and height of the ripples calculated from the bottom drift line surface increase (Figure 4b and Table 1). This behavior is in agreement with data obtained for SiO2 films and gold surfaces bombarded with Ar clusters [19][22]. The process of ripple formation is triggered by the
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Published 24 Feb 2020

Implementation of data-cube pump–probe KPFM on organic solar cells

  • Benjamin Grévin,
  • Olivier Bardagot and
  • Renaud Demadrille

Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24

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  • compositional and/or morphological heterogeneities generating the dark-state SP and SPV contrast play also a key role in the photocarrier trapping process. A reasonable (yet to be definitely confirmed) scenario could invoke the existence of non-percolating PC71BM clusters acting as trapping centers. Such an
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Published 12 Feb 2020

Fabrication of Ag-modified hollow titania spheres via controlled silver diffusion in Ag–TiO2 core–shell nanostructures

  • Bartosz Bartosewicz,
  • Malwina Liszewska,
  • Bogusław Budner,
  • Marta Michalska-Domańska,
  • Krzysztof Kopczyński and
  • Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2020, 11, 141–146, doi:10.3762/bjnano.11.12

Graphical Abstract
  • Ag–TiO2 CSNs, silver cores were fully converted to Ag species (i.e., positively charged Ag clusters as discussed below or other subnanometric silver species) embedded in a titania shell or smaller AgNPs located at the shell surface (Figure 2 E). To the best of our knowledge, the silver diffusion in
  • in Ag@TiO2 CSNs can occur in the following manner. Titania is oxidized in an air atmosphere and as a result, holes, which may further oxidize AgNPs surrounded by the titania shell, are generated. Upon oxidation, AgNPs gain a positive electric charge and may eject positively charged Ag clusters. In
  • case of Ag@TiO2 CSNs and depending on the annealing time, these ejected Ag clusters may either be accommodated within or on the titania shell. In the titania shell, these silver clusters could react with the TiO2 host through the formation of a complex [Ag–(TiO2)] [21]. Upon reaching the surface of the
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Letter
Published 10 Jan 2020

Molecular architectonics of DNA for functional nanoarchitectures

  • Debasis Ghosh,
  • Lakshmi P. Datta and
  • Thimmaiah Govindaraju

Beilstein J. Nanotechnol. 2020, 11, 124–140, doi:10.3762/bjnano.11.11

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Published 09 Jan 2020

Recent progress in perovskite solar cells: the perovskite layer

  • Xianfeng Dai,
  • Ke Xu and
  • Fanan Wei

Beilstein J. Nanotechnol. 2020, 11, 51–60, doi:10.3762/bjnano.11.5

Graphical Abstract
  • contain preformed perovskite clusters, which can be rapidly (within 20 s) deposited on a substrate of an area larger than 100 cm2. The MAPbI3 films formed by the wire-bar (D-bar) coating technique were highly oriented. Smooth high-quality perovskite films with an average PCE of 17.01% were obtained
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Published 06 Jan 2020

Long-term stability and scale-up of noncovalently bound gold nanoparticle-siRNA suspensions

  • Anna V. Epanchintseva,
  • Julia E. Poletaeva,
  • Dmitrii V. Pyshnyi,
  • Elena I. Ryabchikova and
  • Inna A. Pyshnaya

Beilstein J. Nanotechnol. 2019, 10, 2568–2578, doi:10.3762/bjnano.10.248

Graphical Abstract
  • suspension at 4 °C for different times resulted in the formation of particle clusters of high colloidal stability as demonstrated by conventional methods. These clusters completely disintegrated when albumin was added, indicating that they are agglomerates (and not aggregates) of AuNP-siRNA. The AuNPs-siRNA
  • and Figure 3A). The appearance of rounded clusters of AuNP-siRNA with a diameter of not more than 200 nm was a consequence of aggregation/agglomeration of particles over the course of one day (Figure 3E). The particles in the clusters were arranged in several layers and were distinguishable. The
  • scanning probe image processor (SPIP) analysis of the TEM image showed a predominance of clusters with a size of up to 100 nm in samples ×1 and ×10 (85–90% of the total number of clusters); about 10% of clusters had a size of 100–200 nm. Thus, the TEM study showed a tendency towards clumping of the AuNP
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Published 23 Dec 2019

Advanced hybrid nanomaterials

  • Andreas Taubert,
  • Fabrice Leroux,
  • Pierre Rabu and
  • Verónica de Zea Bermudez

Beilstein J. Nanotechnol. 2019, 10, 2563–2567, doi:10.3762/bjnano.10.247

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  • synthesize clusters, so-called colloidal molecules [21]. Nanospherical satellites were covalently bonded via amide groups within the dimples of valence-endowed patchy nanoparticles, allowing the tuning of their topology and self-assembling ability. Polyion complex micelles formed by complexation between poly
  • is the focus of an article reporting the performance of functionalized gold clusters deposited on ZrO2 nanoparticles for benzyl alcohol oxidation in [39]. Interestingly, the defunctionalized gold nanoclusters exhibit full catalytic conversion. Overall, this thematic issue clearly highlights not only
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Editorial
Published 20 Dec 2019

Formation of metal/semiconductor Cu–Si composite nanostructures

  • Natalya V. Yumozhapova,
  • Andrey V. Nomoev,
  • Vyacheslav V. Syzrantsev and
  • Erzhena C. Khartaeva

Beilstein J. Nanotechnol. 2019, 10, 2497–2504, doi:10.3762/bjnano.10.240

Graphical Abstract
  • Verlet algorithm. The visualisation and analysis of the simulation results was carried out in the OVITO program [26][27]. Figure 2 shows clusters with different silicon content at 1.5 ns after the start of simulation. As revealed in [23], with a low silicon content of 10 atom %, a core–shell structure is
  • structure, in particular, the size and phase composition of the nanoparticles has been presented in [5]. The analysis of the obtained data on atomic dynamics in nanoscale clusters showed that at a cooling rate of 1.5 K/ps, a core–shell structure is formed in 70% of the clusters and the Janus-like structure
  • is formed in 30% of the clusters. In the obtained cluster structures, twinning prevails as a mixture of the icosahedral (IR) and dodecahedral (DK) phase (Figure 3a). With a decrease in the cooling rate to 1 K/ps, the probability of the formation of the Janus-like structure increases to 50%. In
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Published 13 Dec 2019

Label-free highly sensitive probe detection with novel hierarchical SERS substrates fabricated by nanoindentation and chemical reaction methods

  • Jingran Zhang,
  • Tianqi Jia,
  • Yongda Yan,
  • Li Wang,
  • Peng Miao,
  • Yimin Han,
  • Xinming Zhang,
  • Guangfeng Shi,
  • Yanquan Geng,
  • Zhankun Weng,
  • Daniel Laipple and
  • Zuobin Wang

Beilstein J. Nanotechnol. 2019, 10, 2483–2496, doi:10.3762/bjnano.10.239

Graphical Abstract
  • beam lithography and self-assembly methods to fabricate gold clusters of micrometer size and regular spacing. Subsequently, the detection resolution of 4-acetamidothiophenol was 0.05 g/L using the substrate. Nanoparticle cluster array structures with a size of 40 nm were fabricated by electron beam
  • pyramidal hierarchical SERS substrates with higher sensitivity can be achieved. Therefore, the combination of Ag nanoparticle clusters on the pile-up of copper surface leads to a new nanogap and improves the density of SERS hotspots. The electric field intensity of the hierarchical substrate on the pile-ups
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Published 13 Dec 2019
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