The role of gold atom concentration in the formation of Cu–Au nanoparticles from the gas phase

• Yuri Ya. Gafner,
• Svetlana L. Gafner,
• Darya A. Ryzkova and
• Andrey V. Nomoev

Beilstein J. Nanotechnol. 2021, 12, 72–81, doi:10.3762/bjnano.12.6

• copper and gold are practically equal (Tm = 1358 K and Tm = 1337 K, respectively). However, this is no longer true in the nanoscale case. The MD modeling [21][23] showed that at an equal size (D < 10 nm), the melting temperature of copper nanoclusters is 30–40% higher than that of gold clusters, which

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

• 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

• of the wetting layer is forced to decrease during the cooling process, as shown in Figure 3. Very small gold clusters (<10 nm) are visible between the droplets. This indicates that the wetting layer collapses during cooling. It remains unclear whether the wetting layer completely disappears into

• these clusters or if it just becomes thinner or perforated. However, the TEM data do not show any evidence of a wetting layer at room temperature, since at this temperature only very small gold clusters are seen. This is in agreement with low-energy electron microscopy (LEEM) calculations, which predict

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

• ], 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

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

• 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

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

• 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

Porous silver-coated pNIPAM-co-AAc hydrogel nanocapsules

• William W. Bryan,
• Riddhiman Medhi,
• Maria D. Marquez,
• Supparesk Rittikulsittichai,
• Michael Tran and
• T. Randall Lee

Beilstein J. Nanotechnol. 2019, 10, 1973–1982, doi:10.3762/bjnano.10.194

• -magnification image of a THPC gold-seeded pDADMAC-modified pNIPAM-co-AAc hydrogel core particle. Due to insufficient electron density in the pNIPAM-co-AAc, the polymer core is not visible by TEM. However, due to the consistent size measurements of the gold clusters, and the absence of randomness in the gold

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

• 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

Thermal control of the defunctionalization of supported Au₂₅(glutathione)₁₈ catalysts for benzyl alcohol oxidation

• Zahraa Shahin,
• Hyewon Ji,
• Rodica Chiriac,
• Nadine Essayem,
• Franck Rataboul and
• Aude Demessence

Beilstein J. Nanotechnol. 2019, 10, 228–237, doi:10.3762/bjnano.10.21

• activity and selectivity of the heterogeneously catalyzed benzyl alcohol oxidation. Results and Discussion Catalyst characterization A Au25(SG)18@ZrO2 composite material (A), with a theoretical gold loading of 1 wt % Au, was prepared by depositing Au25(SG)18 gold clusters on ZrO2 nanoparticles. Zirconium

• ) under air on pure Au25(SG)18 gold clusters, gold clusters deposited on ZrO2 and ZrO2 alone. From the TGA curve of the clusters, a first gradual weight loss of 6.5% is observed before 200 °C, corresponding to the evaporation of the solvent (Figure 1a). Then a second gradual weight loss of 46.2% happens

• general, supported gold thiolate clusters are known to grow when calcined at high temperature [24], except when they are inserted in a porous material, such as SBA-15 [21], or loaded with a very small quantity of clusters [22]. Here we note that the gold clusters maintain a diameter of around 2 nm or

Comparative biological effects of spherical noble metal nanoparticles (Rh, Pd, Ag, Pt, Au) with 4–8 nm diameter

• Alexander Rostek,
• Marina Breisch,
• Kevin Pappert,
• Kateryna Loza,
• Marc Heggen,
• Manfred Köller,
• Christina Sengstock and
• Matthias Epple

Beilstein J. Nanotechnol. 2018, 9, 2763–2774, doi:10.3762/bjnano.9.258

• human cells [24][26][27], whereas in other studies, these effects were not observed [28][29][30]. With ultrasmall gold nanoparticles and gold clusters, different biological events are triggered that can lead to a higher cytotoxicity of very small particles (<3 nm) [31]. Very little is known about the

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

• particles can be of importance. This was demonstrated by MD simulations for gold clusters on HOPG, where a significant reduction of static friction was found by simply increasing the cluster thickness. As a result, the nanostructure becomes elastically stiffer, which goes along with a reduced tendency to

Noble metal-modified titania with visible-light activity for the decomposition of microorganisms

• Maya Endo,
• Zhishun Wei,
• Kunlei Wang,
• Baris Karabiyik,
• Kenta Yoshiiri,
• Paulina Rokicka,
• Bunsho Ohtani,
• Agata Markowska-Szczupak and
• Ewa Kowalska

Beilstein J. Nanotechnol. 2018, 9, 829–841, doi:10.3762/bjnano.9.77

• samples modified with noble metal NPs (NMNPs) were investigated. The NMNPs differ in crystallographic composition, crystallite sizes and specific surface area. It was confirmed that properties of titania influenced the resultant properties of NMNPs [53], as shown in Table 1. Min et al. proposed that gold

• clusters were preferentially deposited on surface defects of the support [55]. Therefore, fine titania with a high number of defects (electron traps, ETs) induced the formation of fine and well-dispersed NMNPs on titania surface, as shown in Figure 1 (top). In contrast, titania with large crystals (low

Au₅₅, a stable glassy cluster: results of ab initio calculations

• Dieter Vollath,
• David Holec and
• Franz Dieter Fischer

Beilstein J. Nanotechnol. 2017, 8, 2221–2229, doi:10.3762/bjnano.8.222

• using high-resolution electron microscopy [12][13][14] were performed. Importantly, these studies pointed out that the structure of small gold clusters was unstable; rather fluctuations between different shapes, primarily, between icosahedral and cuboctahedral habitus were observed [12]. A theoretical

• cluster with the lowest energy as non-crystalline and the structure of the neighboring Au56 cluster as fcc-based structure. Cox et al. [17] interpreted their results as highly symmetric. In contrast, Michaelian et al. [18] obtained a low-symmetry structure. Erkoc [19] analyzed a series of gold clusters in

• interatomic distances leading to dAu55 = (2.804 ± 0.168) × 10−10 m. This value is nearly identical to dAu55 = (2.80 ± 0.01) × 10−10 m, a value determined experimentally by Marcus et al. [10] using ligand-stabilized gold clusters. Both values are significantly smaller than the value for bulk gold dbulk = 2.855

Influence of hydrofluoric acid treatment on electroless deposition of Au clusters

• Rachela G. Milazzo,
• Antonio M. Mio,
• Giuseppe D’Arrigo,
• Emanuele Smecca,
• Alessandra Alberti,
• Gabriele Fisichella,
• Filippo Giannazzo,
• Corrado Spinella and
• Emanuele Rimini

Beilstein J. Nanotechnol. 2017, 8, 183–189, doi:10.3762/bjnano.8.19

• . The gold clusters are characterized by the presence of flat regions and quasispherical particles consistent with the layer-by-layer or island growth modes, respectively. The cleaning procedure, including HF immersion prior to deposition, affects the predominantly occurring gold structures. Flat

• surface. The process stops after a certain thickness of oxide is formed and on top of it gold atoms agglomerate as solid clusters [18][19][20][21]. The optical properties of these gold clusters depend on their shape and morphology. It is reported in literature that the local field enhancement factor of

Rigid multipodal platforms for metal surfaces

• Michal Valášek,
• Marcin Lindner and
• Marcel Mayor

Beilstein J. Nanotechnol. 2016, 7, 374–405, doi:10.3762/bjnano.7.34

• around 0.8 eV [66], which can lead to the removal of small gold clusters by mechanically removing thiols. The versatility of the thiol anchoring guarantees a dense coverage of both flat and rough gold surfaces. The clean close packed Au(111) surface exhibits a hexagonal arrangement of atoms with a well

Surface-site reactivity in small-molecule adsorption: A theoretical study of thiol binding on multi-coordinated gold clusters

• Elvis C. M. Ting,
• Tatiana Popa and
• Irina Paci

Beilstein J. Nanotechnol. 2016, 7, 53–61, doi:10.3762/bjnano.7.6

• for various sites. Kink sites were preferred binding locations due to the availability of multiple surface atoms for dispersive interactions with the methyl groups, whereas tip sites experienced low affinity, despite having low coordination numbers. Keywords: coordination; gold clusters; methylthiol

Bright photoluminescence from ordered arrays of SiGe nanowires grown on Si(111)

• D. J. Lockwood,
• N. L. Rowell,
• A. Benkouider,
• A. Ronda,
• L. Favre and
• I. Berbezier

Beilstein J. Nanotechnol. 2014, 5, 2498–2504, doi:10.3762/bjnano.5.259

• dioxide prevents further metal ion reduction. Since the gold salt reduction process is not possible on SiO2, the reaction immediately stops after the formation of SiO2 [30]. After the selective galvanic deposition of gold clusters on the substrate, the samples were loaded into the MBE chamber. The phase

Nanostructure sensitization of transition metal oxides for visible-light photocatalysis

• Hongjun Chen and
• Lianzhou Wang

Beilstein J. Nanotechnol. 2014, 5, 696–710, doi:10.3762/bjnano.5.82

• the entire solar spectrum [85]. Therefore, it is of great interest to develop novel classes of plasmonic nanostructures photosensitized transition metal oxides with higher photoconversion efficiency. Recently, new findings have been published. For example, Tatsuma et al. found that gold clusters can

• also be utilized as “organic dyes” for the conversion of light to current under visible and/or near-infrared light irradiation [90][91][92]. These gold clusters with tens of atoms are much smaller than gold nanoparticles, which caused gold clusters to exhibit no localized SPR but a molecular orbital

• the monolayer of MoS2 has great potential as a photosensitizer in the near future. In addition to monolayer MoS2, the nanostructures of gold clusters and carbon nanodots are still in a stage of early development, providing numerous challenges and opportunities for future investigation. Although

Injection of ligand-free gold and silver nanoparticles into murine embryos does not impact pre-implantation development

• Ulrike Taylor,
• Wiebke Garrels,
• Annette Barchanski,
• Svea Peterson,
• Laszlo Sajti,
• Andrea Lucas-Hahn,
• Lisa Gamrad,
• Ulrich Baulain,
• Sabine Klein,
• Wilfried A. Kues,
• Stephan Barcikowski and
• Detlef Rath

Beilstein J. Nanotechnol. 2014, 5, 677–688, doi:10.3762/bjnano.5.80

• inert, the sole exception being one study reporting an embryotoxic effect of gold clusters (nanoparticles < 2 nm) after applying an extraordinary high number dose of 1014 NP/embryo [15]. Comparatively well studied is also the effect of nanoparticles on avian embryos. Chicken embryos were exposed to

• only one study reported embryotoxic effects of gold clusters after application of a tremendously high dose (1014 NP/embryo) [15]. Thus, our findings confirm the presumption that gold nanoparticles are highly biocompatible and can safely be developed for biomedical applications, such as novel biomarkers

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

• radial and in azimuthal mode. This proves that our confocal luminescence patterns depict particle plasmon enhancements. Continuous gold clusters cannot be excited as efficiently as the separated nano-triangles. As a first conclusion, we found that the gold Fischer patterns on glass yielded luminescence

Towards a scalable and accurate quantum approach for describing vibrations of molecule–metal interfaces

• David M. Benoit,
• Bruno Madebene,
• Inga Ulusoy,
• Luis Mancera,
• Yohann Scribano and
• Sergey Chulkov

Beilstein J. Nanotechnol. 2011, 2, 427–447, doi:10.3762/bjnano.2.48

• efficient computational tool. We also present results on the vibrational spectrum of hydrogen fluoride on pyrene, on the thiophene molecule in the gas phase, and on small neutral gold clusters. Keywords: computational scaling; grid computing; molecule–metal interactions; periodic density functional theory

• calculated from a PES constructed with periodic density functional theory (DFT), and an assessment of DFT for the description of properties of small neutral gold clusters is given. We conclude this paper with an outlook on future work in the field of theoretical descriptions of vibrational spectra of

Manipulation of gold colloidal nanoparticles with atomic force microscopy in dynamic mode: influence of particle–substrate chemistry and morphology, and of operating conditions

• Samer Darwich,
• Karine Mougin,
• Akshata Rao,
• Enrico Gnecco,
• Shrisudersan Jayaraman and
• Hamidou Haidara

Beilstein J. Nanotechnol. 2011, 2, 85–98, doi:10.3762/bjnano.2.10

• detection (colorimetric and surface enhanced Raman spectroscopy (SERS)). For different reasons gold particles are particularly attractive in this field. For instance, they are ideal electrodes for molecular electronics [22]. Gold clusters below 5 nm in size deposited onto thin metal oxides also exhibit