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Search for "seeds" in Full Text gives 83 result(s) in Beilstein Journal of Nanotechnology.
The rational design of a Au(I) precursor for focused electron beam induced deposition
Beilstein J. Nanotechnol. 2017, 8, 2753–2765, doi:10.3762/bjnano.8.274
- . High-purity Au deposits are of interest for many applications, such as the directed self-assembly of functional organic molecules [45], seeds for the growth of nanorods or nanotubes [46] and for plasmonics [47]. Two Au(I) compounds have been used for the deposition of pure gold. Utke et al
The role of ligands in coinage-metal nanoparticles for electronics
Beilstein J. Nanotechnol. 2017, 8, 2625–2639, doi:10.3762/bjnano.8.263
- depending on their binding affinity on different facets. They cover the nuclei as they form from the molecular precursor and prevent their aggregation [63]. Once the nuclei have grown into structurally well-defined seeds, the ligands can lead to preferential capping, hindering or promoting the growth of
- combination with ascorbic acid and spherical silver seeds yielded rod-like structures in water by reduction of AgNO3. Jana, Gearheart, and Murphy suggested that CTAB forms micellar templates for the anisotropic growth of nanostructures [65]. Recent studies modified this picture and indicated that CTAB
- passivates certain crystal faces (circumferential {100} planes), promoting the growth of nanorods along the ends. It depends on the structure of the initially formed seeds whether the growth occurs in one or two directions [66][67]. Silver nanobars were synthesized in ethylene glycol by the reduction of
Localized growth of carbon nanotubes via lithographic fabrication of metallic deposits
Beilstein J. Nanotechnol. 2017, 8, 2592–2605, doi:10.3762/bjnano.8.260
- morphology, for example, as individual nanotubes or as CNT forests. Electron beam induced deposition (EBID) with subsequent autocatalytic growth (AG) was applied to lithographically produce catalytically active seeds for the localized growth of CNTs via chemical vapor deposition (CVD). With the precursor Fe
- (CO)5 we were able to fabricate clean iron deposits via EBID and AG. After the proof-of-principle that these Fe deposits indeed act as seeds for the growth of CNTs, the influence of significant EBID/AG parameters on the deposit shape and finally the yield and morphology of the grown CNTs was
- catalysts to synthesize well-defined CNTs with controllable morphology via CVD. The influence of the chemical composition and, in particular, of the fabrication parameters (i.e., electron dose and AG time) of Fe deposits were investigated with respect to their suitability and properties as seeds for
Advances and challenges in the field of plasma polymer nanoparticles
Beilstein J. Nanotechnol. 2017, 8, 2002–2014, doi:10.3762/bjnano.8.200
- 16c,d shows their counterparts deposited over the preseeded nylon-sputtered NPs. As expected, normal depositions produce compact coatings with the surface replicating the underlying structure (correspondingly, smooth blank Si or roughened NP seeds). Using GLAD, a columnar structure develops with
Comprehensive Raman study of epitaxial silicene-related phases on Ag(111)
Beilstein J. Nanotechnol. 2017, 8, 1357–1365, doi:10.3762/bjnano.8.137
- temperatures (≤20 °C) leads to a similar result. It was recently suggested that impinging Si atoms at room temperature penetrate the Ag(111) surface, exchange with Ag atoms and act as seeds for the growth of recessed islands [29]. At the same time the released Ag atoms would form new Ag(111) terraces by a
Optical response of heterogeneous polymer layers containing silver nanostructures
Beilstein J. Nanotechnol. 2017, 8, 1065–1072, doi:10.3762/bjnano.8.108
- synthesized, the nanospheres and nanoprisms were at first dispersed in water. The growth of the nanoprisms was fulfilled in two steps: first spherical seeds with specific crystallographic defects were produced, and second, the growth took place on these defects to form nanoprisms [18][21][22]. The absorption
- of the colloidal solutions of the first and second step, as seeds and prisms (Figure 1a), shows the characteristic plasmonic absorption peaks. The peaks 1 and 1’ were identified as the dipolar resonance of the nanoprisms and the nanospheres, respectively. The dipolar resonance of the nanoprisms
- induced absorption between 540–750 nm. The width of this absorption was not due to the distribution in size of the NPs, but rather to the random orientation of the NPs in the solution. The nanoprisms, as synthetized, are visualized in TEM images (Figure 1b). The residual seeds are removed by successive
Formation and shape-control of hierarchical cobalt nanostructures using quaternary ammonium salts in aqueous media
Beilstein J. Nanotechnol. 2017, 8, 494–505, doi:10.3762/bjnano.8.53
- temperature was maintained at 27 °C unless mentioned otherwise. Synthesis In a typical procedure, cobalt chloride hexahydrate (CoCl2·6H2O) was reduced by sodium borohydride (NaBH4) to obtain spherical cobalt seed nanoparticles with an average size of 29 ± 3 nm. These seeds were washed with an ethanol–water
- ambient conditions and under zero shear is discussed first. The critical steps for the formation of nanoplates are the twinning of seed crystals, the size reduction of particles and their controlled assembly to form two-dimensional nanoplates. The cobalt seeds are small spherical nanoparticles of ca. 30
- –50 nm that show no surface defects or faults (Figure S2, Supporting Information File 1). A mixed population of twinned and un-twinned spherical nanoparticles with an average particle of ca. 15 nm is obtained (Figure 3a) when these seeds are ultrasonicated followed by the instantaneous addition of
Biological and biomimetic materials and surfaces
Beilstein J. Nanotechnol. 2017, 8, 403–407, doi:10.3762/bjnano.8.42
- Barthlott studied the micro- and nanostructures on the surfaces of plant leaves, flowers, seeds and pollen during his Ph.D. thesis at the University of Heidelberg using one of the first scanning electron microscopes (SEMs) available for German botanists. His main interest in these years was plant
Innovations from the “ivory tower”: Wilhelm Barthlott and the paradigm shift in surface science
Beilstein J. Nanotechnol. 2017, 8, 394–402, doi:10.3762/bjnano.8.41
- , the unique natural history of isolated rocky outcrops called inselbergs, or the global distribution of biodiversity), plant surfaces and especially the tremendous diversity of minute structures on leaves, fruits, seeds and other parts of plants represent a common thread through 40 years of scientific
- microscopes in German botany and started to intensively study the fascinating world of micro- and nanostructures of leaves, flowers, seeds or pollen grains. Starting point was a distinct interest in systematics, i.e., the science of recording and arranging organisms according to their relation to each other
- characteristic for distinct genera, families or higher-order groups. One of the first structures studied in detail were seeds [3][4][5][6][7][8]. Apart from the sole description of structures based on the surveys functional aspects of plants were always considered as well [3][6][9][10][11]. Soon, and even more
Association of aescin with β- and γ-cyclodextrins studied by DFT calculations and spectroscopic methods
Beilstein J. Nanotechnol. 2017, 8, 348–357, doi:10.3762/bjnano.8.37
- the seeds of the horse chestnut tree, Aesculus hippocastanum (Hippocastanaceae). It is a natural mixture of acylated triterpene glycosides. In early studies, the saponins present in aescin were divided into two forms, α-aescin and β-aescin, with distinct melting point, hemolytic index, specific
“Sticky invasion” – the physical properties of Plantago lanceolata L. seed mucilage
Beilstein J. Nanotechnol. 2016, 7, 1918–1927, doi:10.3762/bjnano.7.183
- , D-24118 Kiel, Germany 10.3762/bjnano.7.183 Abstract The mucilage envelope of seeds has various functions including the provision of different ways for the dispersal of diaspores. Chemical composition and water content of the mucilage yield particular adhesive and frictional properties in the
- envelope that also influence the dispersal of seeds. To determine the physical properties of Plantago lanceolata seed mucilage we studied (1) composition, (2) desiccation, (3) adhesion, and (4) friction properties of the mucilage under different hydration conditions. We revealed the presence of cellulose
- mucilage against loss from the seed surface. Keywords: adhesion; cellulose mucilage; desiccation; friction; Plantago lanceolata; Introduction The ability of seeds and fruits (diaspores) to form mucilage after hydration is known as myxospermy [1][2]. The mucilaginous diaspores are particularly
Tunable longitudinal modes in extended silver nanoparticle assemblies
Beilstein J. Nanotechnol. 2016, 7, 1219–1228, doi:10.3762/bjnano.7.113
- transparent in the entire visible region using Pd decahedra as seeds [37]. In Luo’s work, the longitudinal band was pushed to the near infra-red region with nanorods of aspect ratios greater than 3.9. This is due to the energy dampening as the plasmon oscillation travels a longer distance on the rod surface
Voltammetric determination of polyphenolic content in pomegranate juice using a poly(gallic acid)/multiwalled carbon nanotube modified electrode
Beilstein J. Nanotechnol. 2016, 7, 1104–1112, doi:10.3762/bjnano.7.103
- /s. Preparation of pomegranate juice sample and determination of total phenolic content The pomegranate juice was obtained by peeling the fruits by hand and the seeds were liquefied using a hand press. The obtained juice was filtered off through a Whatman filter paper (No. 1). An aliquot of 10.0 mL
Sandwich-like layer-by-layer assembly of gold nanoparticles with tunable SERS properties
Beilstein J. Nanotechnol. 2016, 7, 1028–1032, doi:10.3762/bjnano.7.95
- be assembled onto polyelectrolyte multilayer films and act as seeds for the following NP growth [16]. The grown NP films were demonstrated to be stable and reproducible SERS substrates. In addition to assembling only one type of NPs, Zhang et al. fabricated bimetallic gold–silver multilayer films by
Direct formation of gold nanorods on surfaces using polymer-immobilised gold seeds
Beilstein J. Nanotechnol. 2016, 7, 809–816, doi:10.3762/bjnano.7.72
- direct growth on surfaces that were pre-coated with polymer-immobilised gold seeds. A Au–PMMA nanocomposite formed by UV photoreduction has been used as the gold seed. The influence of polymer Mw and gold concentration on the formation of GNRs has been investigated and discussed. The polymer
- nanowires (NWs) occurs directly on the surfaces using small metal nanoparticles as seeds to grow the NRs, similar to the direct growth of carbon nanotubes and semiconductor 1D nanostructures from catalytic seeds [5]. Direct growth of GNRs on surfaces has been reported in many publications [6][7][8]. Au seed
- particles usually bond to the pre-functionalised surfaces using various chemical linkers [9][10]. The substrate is then immersed in a growth solution, which results in the growth of surface-bound seeds into 1D nanostructures, quite similar to seed-mediated growth in solution. Seed-mediated growth is one of
Surface coating affects behavior of metallic nanoparticles in a biological environment
Beilstein J. Nanotechnol. 2016, 7, 246–262, doi:10.3762/bjnano.7.23
- of seed into nanocrystals. The mechanism behind such a synthesis is extremely complicated, but the type of coating agent proved to be crucial for the final shape of a nanocrystal [66]. The micrographs presented in Figure 8 suggest that our initially small AgNPs appeared as seeds in WhBl or BlPl
Green and energy-efficient methods for the production of metallic nanoparticles
Beilstein J. Nanotechnol. 2015, 6, 2354–2376, doi:10.3762/bjnano.6.243
Morphology control of zinc oxide films via polysaccharide-mediated, low temperature, chemical bath deposition
Beilstein J. Nanotechnol. 2015, 6, 799–808, doi:10.3762/bjnano.6.83
- . Results and Discussion ZnO films were prepared according to the three-step process described in the Experimental section and depicted in Figure 1. Step 1: Seeding The solution-based growth of zincite in general requires prior application of crystalline seeds on the support. In our work, the solution
- originating from the amorphous glass (data not shown). FE-SEM also failed to visualize the seeds on the glass slides, probably due to their small size and the strong electric charging of the substrate. However, indirect evidence of a successful seeding was possible. Contact angle measurements showed that the
- % were observed in the visible range. Combining the results from XRD and FE-SEM investigations to form a cohesive theory, we propose the following mechanism for the film formation, as illustrated in Figure 7. First, the seeds deposited during the first step support the growth of ZnO. On such seeds, an
Nanoparticle shapes by using Wulff constructions and first-principles calculations
Beilstein J. Nanotechnol. 2015, 6, 361–368, doi:10.3762/bjnano.6.35
- adsorption of halides to particular facets reduces the surface energy of those facets and typically they are represented more in the equilibrium state of the particle. This has been observed for the appearance of nanocubes of Ag grown on Au seeds in the presence of chlorine [59]. In some cases a symmetry
Mechanical properties of MDCK II cells exposed to gold nanorods
Beilstein J. Nanotechnol. 2015, 6, 223–231, doi:10.3762/bjnano.6.21
- after reaching confluence by washing with PBS, followed by trypsinization and centrifugation at 110g. Particle synthesis and characterization Gold nanorods and nanospheres were prepared as described previously following the seeded growth method [25]. First, seeds were prepared by adding 0.6 mL of ice
Mammalian cell growth on gold nanoparticle-decorated substrates is influenced by the nanoparticle coating
Beilstein J. Nanotechnol. 2014, 5, 2479–2488, doi:10.3762/bjnano.5.257
- (>18 MΩ, Milli-Q) was used in all experiments. Suppliers of chemicals are given in the Supporting Information File 1. Particle synthesis Gold nanorods were synthesized according to the seeded growth method published by Nikoobakht [34] as presented in [20]. In a first step, the seeds were prepared by
Synthesis and characterization of fluorescence-labelled silica core-shell and noble metal-decorated ceria nanoparticles
Beilstein J. Nanotechnol. 2014, 5, 2413–2423, doi:10.3762/bjnano.5.251
- 120 °C [48]. Under these conditions, nitrate acts as oxidizing agent, and the reaction can be done in closed vessels. The overall reaction is 3Ce3+ + NO3− + 4H2O → 3CeO2 + NO + 8H+. The authors suggest that PVP interacts with the crystal seeds and prevents an increase in size over the limit of 8–10 nm
- reaction time is necessary to allow for attachment of the precursor to the ceria NP by slow ligand exchange at the noble metal, replacing Cl− with the hydroxy groups at the surface, which results in the formation of nucleation seeds directly at ceria. Reduction with KBH4 leads to the desired decorated
Inorganic Janus particles for biomedical applications
Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244
- ]. These inorganic Janus particles consisting of two different core materials are obtained either via a seed-mediated route using performed seeds or as a one-pot synthesis. However, in both cases the heterogeneous nucleation of a second or third component is taking place, limiting these techniques to
- material combinations where epitaxial growth is possible [7][60]. In order to create hetero-nanoparticles, it is crucial to suppress homogeneous nucleation of the second (or third) component as competitive reaction to heterogeneous nucleation on the preformed or in situ formed seeds. Following classical
- theory of heterogeneous nucleation, this can be achieved by decreasing the concentration of the precursor below supersaturation, at which the homogeneous nucleation would be favourable [61]. Furthermore, the additional term of Gibbs free energy for the adhesive energy at the interface between the seeds
Synthesis, characterization, and growth simulations of Cu–Pt bimetallic nanoclusters
Beilstein J. Nanotechnol. 2014, 5, 1371–1379, doi:10.3762/bjnano.5.150
- novel simulation method to study the growth mechanism of CuPt bimetallic nanoclusters; in particular, we explored the attaching of Pt atoms on Cu seeds by using grand-canonical Langevin dynamics (GCLD) simulations, which shows the formation of alloy structures in good agreement with empirical evidence
- order of the metal atoms increases, since atoms inside the NP (higher coordination number) are not expected to interact with the solvent as much as the atoms in the surface (lower coordination). Following the experimental evidence, fcc structures were selected as Cu seeds for Pt growing. In particular
- we have employed the truncated octahedron (TO), the surface of which holds six square (100) faces and eight equilateral hexagonal (111) faces. TO structures of two sizes (n = 201 and n = 586) were used as seeds, which correspond to a diameter of 1.6 and 2.4 nm respectively. The simulations were
Electron-beam induced deposition and autocatalytic decomposition of Co(CO)3NO
Beilstein J. Nanotechnol. 2014, 5, 1175–1185, doi:10.3762/bjnano.5.129
- insight into the underlying reaction(s), chemically more sensitive methods like XPS and IR spectroscopy may be helpful. The apparent cobalt thickness observed on the thick Fe seed layers is 7.4 ± 0.8 nm; the average growth rate is 0.35 ± 0.05 Å/min. It is likely, however, that the growth on Fe seeds
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