Fabrication and characterization of Si_1−xGe_x nanocrystals in as-grown and annealed structures: a comparative study

• Muhammad Taha Sultan,
• Adrian Valentin Maraloiu,
• Ionel Stavarache,
• Jón Tómas Gudmundsson,
• Andrei Manolescu,
• Valentin Serban Teodorescu,
• Magdalena Lidia Ciurea and
• Halldór Gudfinnur Svavarsson

Beilstein J. Nanotechnol. 2019, 10, 1873–1882, doi:10.3762/bjnano.10.182

• HiPIMS and dcMS followed by rapid thermal annealing (1 min) at different temperatures. It is shown that HiPIMS deposition facilitates the formation of small nanoparticles/clusters in the as-grown structures. A suitable selection of annealing temperature and time results in the columnar self-assembly of

Engineered superparamagnetic iron oxide nanoparticles (SPIONs) for dual-modality imaging of intracranial glioblastoma via EGFRvIII targeting

• Xianping Liu,
• Chengjuan Du,
• Haichun Li,
• Ting Jiang,
• Zimiao Luo,
• Zhiqing Pang,
• Daoying Geng and
• Jun Zhang

Beilstein J. Nanotechnol. 2019, 10, 1860–1872, doi:10.3762/bjnano.10.181

• size of whole clusters was around 100 nm, which is much larger than the diameter as determined by TEM. This discrepancy might be due to nanoprobe cluster formation in water. Nanoparticles of diameter around 110 nm can successfully escape the phagocytosis of the reticuloendothelial system (RES) and

Toxicity and safety study of silver and gold nanoparticles functionalized with cysteine and glutathione

• Barbara Pem,
• Igor M. Pongrac,
• Lea Ulm,
• Ivan Pavičić,
• Valerije Vrček,
• Darija Domazet Jurašin,
• Marija Ljubojević,
• Adela Krivohlavek and
• Ivana Vinković Vrček

Beilstein J. Nanotechnol. 2019, 10, 1802–1817, doi:10.3762/bjnano.10.175

• lead to the formation of thiol-coated AgNPs [48]. New clusters consisting of Ag2S can be created from free Ag+ [47]. This process, known as sulfidation, affects AgNP behavior in the biological system [49], most notably by reducing their toxicity [47][50]. The binding of thiols to AuNP surfaces has been

Synthesis of nickel/gallium nanoalloys using a dual-source approach in 1-alkyl-3-methylimidazole ionic liquids

• Ilka Simon,
• Julius Hornung,
• Juri Barthel,
• Jörg Thomas,
• Maik Finze,
• Roland A. Fischer and
• Christoph Janiak

Beilstein J. Nanotechnol. 2019, 10, 1754–1767, doi:10.3762/bjnano.10.171

• carbene ligands (NHC) stabilize metal clusters and nanoparticles [44]. By insertion of the transition-metal center into the C2–H bond of imidazolium salts, transition-metal hydride complexes are formed [45]. Finally, H transfer reactions from the transition metal to GaCp* lead to the release of Cp*H

• assume that during the dispersion a chemical reaction of the precursors to Ni/Ga clusters occurs. The formation of clusters from metal precursor materials in ionic liquids has been described before, for example, [EMIm][Ni(P2S8)] [51], [BMMIm]16[Sn24Se56] [52], [Ru2Bi14Br4][AlCl4] [53], [Bi5(AlCl4)3] [53

• ], [Au(Bi8)(AlCl4)5] [54], and [(CuBi8)(AlCl4)] [55] In organic solvents, organometallic Ni complexes, e.g., Ni(COD)2 and Ni(CO)4 are known to form different types of intermetallic clusters with GaCp* and similar compounds, such as Ni(Cp*Ga)(CO)3, Ni4(Cp*Ga)4(CO)6, Ni(GaCp*)4 [46][56][57][58][59][60

The impact of crystal size and temperature on the adsorption-induced flexibility of the Zr-based metal–organic framework DUT-98

• Simon Krause,
• Volodymyr Bon,
• Hongchu Du,
• Rafal E. Dunin-Borkowski,
• Ulrich Stoeck,
• Irena Senkovska and
• Stefan Kaskel

Beilstein J. Nanotechnol. 2019, 10, 1737–1744, doi:10.3762/bjnano.10.169

• supramolecular building blocks (SBBs), which consist of Zr6 clusters interconnected by 3,6-carbazole dicarboxylate ligands [20]. An additional benzoate functionality of the ligand connects the SBB into a 3D framework with a structure (Figure 1) similar to MIL-53 [21][22]. Upon removal of the solvent molecules

• cluster of 1.5 nm, which is in good agreement with the lattice parameter and the inter-cluster distance of the DUT-98op crystal structure (Supporting Information File 1, Figure S8). The regular arrangement of the clusters indicates a high symmetry that matches the tetragonal symmetry in DUT-98op. In

Kelvin probe force microscopy work function characterization of transition metal oxide crystals under ongoing reduction and oxidation

• Dominik Wrana,
• Karol Cieślik,
• Wojciech Belza,
• Christian Rodenbücher,
• Krzysztof Szot and
• Franciszek Krok

Beilstein J. Nanotechnol. 2019, 10, 1596–1607, doi:10.3762/bjnano.10.155

• equiprobable orientations of (√5×√5)R26.6° domains, both rotated with respect to the (1×1) surface by 26.6 degrees. Those two domains are labeled A and B, both in LEED and STM images. Bright protrusions seen in the STM picture, which also decorate domain boundaries, are either oxygen vacancies/vacancy clusters

Materials nanoarchitectonics at two-dimensional liquid interfaces

• Katsuhiko Ariga,
• Michio Matsumoto,
• Taizo Mori and
• Lok Kumar Shrestha

Beilstein J. Nanotechnol. 2019, 10, 1559–1587, doi:10.3762/bjnano.10.153

• systems fabricated with low-dimensional materials are actively investigated. For example, Lvov and co-workers reported the immobilization of small functional materials such as metal clusters and metal catalysts within one-dimensional halloysite clay nanotubes to make them work under appropriate protection

Growth of lithium hydride thin films from solutions: Towards solution atomic layer deposition of lithiated films

• Ivan Kundrata,
• Karol Fröhlich,
• Lubomír Vančo,
• Matej Mičušík and
• Julien Bachmann

Beilstein J. Nanotechnol. 2019, 10, 1443–1451, doi:10.3762/bjnano.10.142

• , indicating and increase in mass with decrease of frequency [21]. SEM images of the surface show clusters of crystals that grew possibly due to bubbles forming in the chamber shown in Figure 3 or the influence of air sensitivity. One such crystal is presented in Figure 9. The film covering the sample appears

Direct observation of oxygen-vacancy formation and structural changes in Bi₂WO₆ nanoflakes induced by electron irradiation

• Hong-long Shi,
• Bin Zou,
• Zi-an Li,
• Min-ting Luo and
• Wen-zhong Wang

Beilstein J. Nanotechnol. 2019, 10, 1434–1442, doi:10.3762/bjnano.10.141

• clusters on the nanoflake surfaces, and the oxygen atoms are released from the nanoflakes, while the W–O networks reconstruct to form WO3. A possible mechanism that accounts for the observed processes of Bi cluster formation and oxygen release under energetic electron irradiation is also discussed

• suggests that released Bi and O do not recrystallize into BiOx; instead the Bi atoms precipitate at the surfaces to form Bi clusters, and the O atoms are released into the vacuum. The background-removed intensity ratio I(110)/I(012) of bismuth precipitates was 0.68, 0.35, 0.83, 1.42, and 1.84 after an

• irradiation, in this case, is far too low to decompose Bi2WO6 nanoflakes. Besides, loops or defect clusters were not observed during the whole irradiation process suggesting that the knock-off or sputtering effects can be neglected. When a high-energy electron beam passes through the sample, an electric field

Gas sensing properties of individual SnO₂ nanowires and SnO₂ sol–gel nanocomposites

• Alexey V. Shaposhnik,
• Dmitry A. Shaposhnik,
• Sergey Yu. Turishchev,
• Olga A. Chuvenkova,
• Stanislav V. Ryabtsev,
• Alexey A. Vasiliev,
• Xavier Vilanova,
• Francisco Hernandez-Ramirez and
• Joan R. Morante

Beilstein J. Nanotechnol. 2019, 10, 1380–1390, doi:10.3762/bjnano.10.136

• occurs, the thin dioxide nanowires begin to crystallize. The diameter of the growing wires is defined by the diameter of the initial tin nanodrops. Such a process, taking place without hetero-element clusters, is called a self-catalytic process. A nanodrop of liquid metal with dissolved tin oxide is

Alloyed Pt₃M (M = Co, Ni) nanoparticles supported on S- and N-doped carbon nanotubes for the oxygen reduction reaction

• Stéphane Louisia,
• Yohann R. J. Thomas,
• Pierre Lecante,
• Marie Heitzmann,
• M. Rosa Axet,
• Pierre-André Jacques and
• Philippe Serp

Beilstein J. Nanotechnol. 2019, 10, 1251–1269, doi:10.3762/bjnano.10.125

• selected area) displaying a Pt3Co composition. The absence of Co NPs in the Co/N-CNT sample, and the composition and structure of the Pt3Co/N-CNTs, indicate that the Pt3Co/N-CNT is more likely an alloy than a core–shell structure. The presence of residual cobalt atoms or clusters on the CNT surface was

• also evidenced by STEM-HAADF images of Pt3Co/N-CNT (Figure 7b, 001 selected area). In the same way, the Pt3Ni composition was determine by EDX analysis for the sample Pt3Ni/N-CNTHT (Supporting Information File 1, Figure S9). This sample also displays some residual nickel atoms or clusters

• obtained with unreacted M atoms (and clusters) at the surface of the carbon support. Catalyst treatment: EDTA washing The previous characterization revealed a large amount of unalloyed cobalt or nickel species on the support surface, which can be easily dissolved in acidic media, which then poisons the

Imaging the surface potential at the steps on the rutile TiO₂(110) surface by Kelvin probe force microscopy

• Masato Miyazaki,
• Huan Fei Wen,
• Quanzhen Zhang,
• Yuuki Adachi,
• Jan Brndiar,
• Ivan Štich,
• Yan Jun Li and
• Yasuhiro Sugawara

Beilstein J. Nanotechnol. 2019, 10, 1228–1236, doi:10.3762/bjnano.10.122

• low coordination and unique charge distribution [16][17][18][19]. In the case of TiO2, steps act as preferential sites for the adsorption of molecules and metal clusters [20][21][22], as active sites for catalytic reactions [23][24][25], and as the central elements of surface reconstructions [26][27

Green fabrication of lanthanide-doped hydroxide-based phosphors: Y(OH)₃:Eu³⁺ nanoparticles for white light generation

• Tugrul Guner,
• Anilcan Kus,
• Mehmet Ozcan,
• Aziz Genc,
• Hasan Sahin and
• Mustafa M. Demir

Beilstein J. Nanotechnol. 2019, 10, 1200–1210, doi:10.3762/bjnano.10.119

• in Figure 1c. These micrographs reveal that the sample consists of agglomerated nanoparticles. The clusters formed by the sub-10 nm nanoparticles have sizes between 50 nm to a few micrometers. It is possible to visualize the individual nanoparticles in the lower left HAADF STEM micrograph where the

Pure and mixed ordered monolayers of tetracyano-2,6-naphthoquinodimethane and hexathiapentacene on the Ag(100) surface

• Robert Harbers,
• Timo Heepenstrick,
• Dmitrii F. Perepichka and
• Moritz Sokolowski

Beilstein J. Nanotechnol. 2019, 10, 1188–1199, doi:10.3762/bjnano.10.118

• that no de-wetting from the Ag(100) surface by formation of small three-dimensional clusters occurred over time. HTPEN forms two different structures on Ag(100) depending on the coverage. The predominantly observed phase has a slightly larger unit cell (ca. 10%) than the second phase with a more

Scavenging of reactive oxygen species by phenolic compound-modified maghemite nanoparticles

• Małgorzata Świętek,
• Yi-Chin Lu,
• Rafał Konefał,
• Liliana P. Ferreira,
• M. Margarida Cruz,
• Yunn-Hwa Ma and
• Daniel Horák

Beilstein J. Nanotechnol. 2019, 10, 1073–1088, doi:10.3762/bjnano.10.108

• , triplets and small clusters), due to the absence of a polymeric steric stabilizer, and of larger particles, which was also confirmed by TEM microscopy (Figure 2b). The ζ-potential of the γ-Fe2O3 particles was positive (ca. 50 mV) due to the presence of cations on the particle surface, originating from

Structural and optical properties of penicillamine-protected gold nanocluster fractions separated by sequential size-selective fractionation

• Xiupei Yang,
• Zhengli Yang,
• Fenglin Tang,
• Jing Xu,
• Maoxue Zhang and
• Martin M. F. Choi

Beilstein J. Nanotechnol. 2019, 10, 955–966, doi:10.3762/bjnano.10.96

• protective layer of organic molecules [2]. These clusters are considered to be a hybrid system of small molecules and macroscopic materials, and are of great interest to the properties of gold core and organic monolayers [3]. The stable monolayer-protected NCs have enabled experiments to be carried out that

• precipitation technique can reduce the ability of a solvent to disperse clusters by adding a miscible non-solvent to the cluster agglomeration point. The larger clusters are first aggregated due to the greater van der Waals attraction between the clusters, and the clusters aggregated can be precipitated by

• centrifugation, and the smaller clusters are still dispersed in the solvent. Herein, we performed SSSP for the polydisperse penicillamine-coated water-soluble AuNCs from aqueous medium using acetone as a nonsolvent. When acetone was gradually added to the aqueous solution of AuNCs to achieve supersaturation of

Effects of gold and PCL- or PLLA-coated silica nanoparticles on brain endothelial cells and the blood–brain barrier

• Aniela Bittner,
• Angélique D. Ducray,
• Hans Rudolf Widmer,
• Michael H. Stoffel and
• Meike Mevissen

Beilstein J. Nanotechnol. 2019, 10, 941–954, doi:10.3762/bjnano.10.95

• these three NP types. Both PLLA- and PCL-NPs were taken up to a high extent after 2 and 24 h of exposure, respectively. They tended to form clusters and were detected freely in the cytosol or in membrane-bound vesicles (Figure 2A,D and Figure 2B,E). On the other hand, Au-NPs could not be found inside

• physicochemical properties, the formation of NP clusters before entry into the cell may modulate the cellular uptake [9][34]. NPs might not only cause cytotoxicity but also hinder proliferation, differentiation or lead to inflammation via activation or inhibition of various pathways including phosphatidylinositol

• , B, C) and higher magnification (D, E, F); analyzed by TEM. PLLA- and PCL-NPs were found in clusters inside the cells (arrows) (A, B; scale bar: 5 µm) and were present freely in the cytoplasm (arrows) or in membrane-bound vesicles (arrow head) (D, E; scale bar: 1 µm). Single Au-NPs were taken up by

Comparing a porphyrin- and a coumarin-based dye adsorbed on NiO(001)

• Sara Freund,
• Antoine Hinaut,
• Nathalie Marinakis,
• Edwin C. Constable,
• Ernst Meyer,
• Catherine E. Housecroft and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2019, 10, 874–881, doi:10.3762/bjnano.10.88

• adsorbed on the substrate, where it can be seen that Cu-TCPP exhibits either the tendency to aggregate in small clusters at step edges and defects, or to form large molecular islands (up to 70 nm in width). The fact that the island formation takes place at RT indicates a relatively high diffusion rate of

• the molecules on NiO(001). The emergence of numerous clusters is related to the presence of various defects on the surface that act as anchoring sites for the dyes. Concentrating on the islands and measuring their heights (250–300 pm), we can conclude that the molecules are lying flat on the substrate

Tungsten disulfide-based nanocomposites for photothermal therapy

• Tzuriel Levin,
• Hagit Sade,
• Rina Ben-Shabbat Binyamini,
• Maayan Pour,
• Iftach Nachman and
• Jean-Paul Lellouche

Beilstein J. Nanotechnol. 2019, 10, 811–822, doi:10.3762/bjnano.10.81

• conjugation of CAN-mag nanoparticles, and later on, of the polymers. At the same time, attachment of CAN-mag to the nanotubes is clearly visible (Figure 2d–f). Rather than conformally coating the nanotubes, CAN-mag nanoparticles seem to attach to the surface of the nanotubes in small clusters, appearing dark

Capillary force-induced superlattice variation atop a nanometer-wide graphene flake and its moiré origin studied by STM

• Loji K. Thomas and
• Michael Reichling

Beilstein J. Nanotechnol. 2019, 10, 804–810, doi:10.3762/bjnano.10.80

• arachidic acid-HOPG interface. Acknowledgements This work has been funded by Georg-Christoph-Lichtenberg-Stipendium from the State government of Niedersachsen, Germany, through the Promotionsprogramm "Synthesis and Characterization of surfaces and Interfaces assembled from Clusters and Molecules".

Features and advantages of flexible silicon nanowires for SERS applications

• Hrvoje Gebavi,
• Vlatko Gašparić,
• Dubravko Risović,
• Nikola Baran,
• Paweł Henryk Albrycht and
• Mile Ivanda

Beilstein J. Nanotechnol. 2019, 10, 725–734, doi:10.3762/bjnano.10.72

• , preferably with clusters of metal nanoparticles, sharp edges and tips, are the key to strong electromagnetic enhancement ranging from 1010 to 1014 [3]. If the values of Raman cross section of the analyte and of SERS enhancement are appropriate, even single-molecule detection is possible. For example, under

Ultrathin hydrophobic films based on the metal organic framework UiO-66-COOH(Zr)

• Miguel A. Andrés,
• Clemence Sicard,
• Christian Serre,
• Olivier Roubeau and
• Ignacio Gascón

Beilstein J. Nanotechnol. 2019, 10, 654–665, doi:10.3762/bjnano.10.65

• . Keywords: hydrophobic coating; Langmuir–Blodgett (LB) films; metal organic framework (MOF); surface modification; UiO-66-COOH(Zr); Introduction Metal organic frameworks (MOFs) are well-known, crystalline, porous materials formed by metal ions (or metallic clusters) and organic ligands coordinated in a pre

• film homogeneity. Interestingly, a recent study has shown that alkyl phosphonic acids, such as ODP, interact with the zirconium oxide clusters situated near and on the surface of Zr-based MOFs and the surface free energy on the exterior of the MOF can be reduced by the octadecyl alkyl chains, spawning

Hydrophilicity and carbon chain length effects on the gas sensing properties of chemoresistive, self-assembled monolayer carbon nanotube sensors

• Juan Casanova-Cháfer,
• Carla Bittencourt and
• Eduard Llobet

Beilstein J. Nanotechnol. 2019, 10, 565–577, doi:10.3762/bjnano.10.58

• more responsive to nitrogen dioxide than Au, Pt or Pd-decorated CNTs when operated at room temperature [10][18][40]. This was attributed to a stronger interaction and charge transfer between nitrogen dioxide and oxygenated defects in CNTs than with metal clusters. Possibly the surface of metal clusters

• requires higher operating temperatures to act as reactive sites for the adsorption of nitrogen dioxide molecules. Therefore, the response obtained for Au-MWCNTs cannot be explained by the catalytic activity of gold clusters at the nanometer range, and instead the resistance changes observed are probably

Quantification and coupling of the electromagnetic and chemical contributions in surface-enhanced Raman scattering

• Yarong Su,
• Yuanzhen Shi,
• Ping Wang,
• Jinglei Du,
• Markus B. Raschke and
• Lin Pang

Beilstein J. Nanotechnol. 2019, 10, 549–556, doi:10.3762/bjnano.10.56

• ]. Only the ω3 mode is thought to be sensitive to charge redistribution due to the nuclear motion of the S-atom with respect to metal substrate and phenyl ring [15]. DFT calculations (Gaussian 09 package) were performed based on benzenethiol bound to three silver atom clusters, for illustration, and the

• displayed in Figure 2a–e. A significant change in the intensity ratio of the different modes is seen, as compared to the neat benzenethiol spectrum. The observed dominance of the ω3 mode is the result of the charge redistribution from the Au/Ag surface clusters to the S atom in benzenethiol associated with

Advanced scanning probe lithography using anatase-to-rutile transition to create localized TiO₂ nanorods

• Julian Kalb,
• Vanessa Knittel and
• Lukas Schmidt-Mende

Beilstein J. Nanotechnol. 2019, 10, 412–418, doi:10.3762/bjnano.10.40

• TiO2 nanorods grow hydrothermally on anatase particles with a diameter of approximately 25 nm [39][40]. Even if rutile TiO2 seed nanocrystals are already present, it is assumed that anatase clusters diffuse along rutile TiO2 surfaces towards low-energy facets and perform a solid-state phase