Synthesis, characterization, and growth simulations of Cu–Pt bimetallic nanoclusters

• Subarna Khanal,
• Ana Spitale,
• Nabraj Bhattarai,
• Daniel Bahena,
• J. Jesus Velazquez-Salazar,
• Sergio Mejía-Rosales,
• Marcelo M. Mariscal and
• Miguel José-Yacaman

Beilstein J. Nanotechnol. 2014, 5, 1371–1379, doi:10.3762/bjnano.5.150

• 66450, México 10.3762/bjnano.5.150 Abstract Highly monodispersed Cu–Pt bimetallic nanoclusters were synthesized by a facile synthesis approach. Analysis of transmission electron microscopy (TEM) and spherical aberration (Cs)-corrected scanning transmission electron microscopy (STEM) images shows that

• the average diameter of the Cu–Pt nanoclusters is 3.0 ± 1.0 nm. The high angle annular dark field (HAADF-STEM) images, intensity profiles, and energy dispersive X-ray spectroscopy (EDX) line scans, allowed us to study the distribution of Cu and Pt with atomistic resolution, finding that Pt is embedded

• –Pt clusters; energy dispersive X-ray spectroscopy (EDX); grand-canonical Langevin dynamics; nanoalloys; scanning transmission electron microscopy (STEM); Introduction The study of bimetallic (BM) nanoclusters has received particular interest because of their myriad properties and applications in

Functionalized nanostructures for enhanced photocatalytic performance under solar light

• Liejin Guo,
• Dengwei Jing,
• Maochang Liu,
• Yubin Chen,
• Shaohua Shen,
• Jinwen Shi and
• Kai Zhang

Beilstein J. Nanotechnol. 2014, 5, 994–1004, doi:10.3762/bjnano.5.113

• semiconductor nanocrystals are dispersed in the mesoporous substrate, greatly enhanced photocatalytic properties can also be achieved. For example, dispersing TiO2 nanoclusters in MCM-41 [13] and MCM-48 [14] resulted in much higher photocatalytic activities than that of bulk TiO2 under UV light irradiation. Our

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

• . For example, Au25 nanoclusters are characterized by molecular-like excited-state properties with well-defined absorption and emission features, which results in Au25 nanoclusters acting as photosensitizer and exhibiting photoinduced electron-transfer properties. This finding may pave the way for the

Plasma-assisted synthesis and high-resolution characterization of anisotropic elemental and bimetallic core–shell magnetic nanoparticles

• M. Hennes,
• A. Lotnyk and
• S. G. Mayr

Beilstein J. Nanotechnol. 2014, 5, 466–475, doi:10.3762/bjnano.5.54

• studies have put Cu/Ni nanoparticular phase diagrams under scrutiny: Thermodynamic equilibrium configurations of nanoclusters were predicted to depend on concentration and structure, and no indications for rotationally symmetric CS configurations were found [22][23]. In addition, the properties of the Cu

• /Ni system compare reasonably well with the Au/Ni system, which –when in the shape of magnetic core/inert shell nanoclusters– is highly promising as easily functionalized carrier in biomedical environments. Although our studies, at the present stage, are targeted at a fundamental physical

3D-nanoarchitectured Pd/Ni catalysts prepared by atomic layer deposition for the electrooxidation of formic acid

• Loïc Assaud,
• Evans Monyoncho,
• Kristina Pitzschel,
• Anis Allagui,
• Matthieu Petit,
• Margrit Hanbücken,
• Elena A. Baranova and
• Lionel Santinacci

Beilstein J. Nanotechnol. 2014, 5, 162–172, doi:10.3762/bjnano.5.16

• °C for 3 h to obtain a metallic Ni layer. The last step of the preparation of the catalysts consisted of depositing Pd nanoclusters that have been grown from palladium(II) hexafluoroacetylacetonate (Pd(hfac)2, 98% from STREM chemicals), and formalin (37% formaldehyde in water with 10–15% of methanol

The role of oxygen and water on molybdenum nanoclusters for electro catalytic ammonia production

• Jakob G. Howalt and
• Tejs Vegge

Beilstein J. Nanotechnol. 2014, 5, 111–120, doi:10.3762/bjnano.5.11

• theory calculations are used in combination with the computational hydrogen electrode approach to calculate the free energy profile for electrochemical protonation of O and N2 species on cuboctahedral Mo13 nanoclusters. The calculations show that the molybdenum nanocluster will preferentially bind oxygen

• V or lower for all oxygen coverages studied, and it is thus possible to (re)activate (partially) oxidized nanoclusters for electrochemical ammonia production, e.g., using a dry proton conductor or an aqueous electrolyte. At lower oxygen coverages, nitrogen molecules can adsorb to the surface and

• electrochemical ammonia production via the associative mechanism is possible at potentials as low as −0.45 V to −0.7 V. Keywords: ammonia; density functional theory; electrocatalysis; nanoparticles; oxygen poisoning; Introduction Molybdenum nanoclusters have been identified as a prime candidate for

Structural, optical and photocatalytic properties of flower-like ZnO nanostructures prepared by a facile wet chemical method

• Sini Kuriakose,
• Neha Bhardwaj,
• Jaspal Singh,
• Biswarup Satpati and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2013, 4, 763–770, doi:10.3762/bjnano.4.87

• into an aqueous solution of Zn(CH3COO)2 leads to the formation of white precipitates of Zn(OH)2 (Equation 1), which upon heating decompose to form ZnO nuclei (Equation 2). Depending on the Zn2+ concentration and synthesis conditions, the ZnO nuclei grow into nanoclusters. In the presence of excess OH

Low-dose patterning of platinum nanoclusters on carbon nanotubes by focused-electron-beam-induced deposition as studied by TEM

• Xiaoxing Ke,
• Carla Bittencourt,
• Sara Bals and
• Gustaaf Van Tendeloo

Beilstein J. Nanotechnol. 2013, 4, 77–86, doi:10.3762/bjnano.4.9

• -induced deposition (FEBID) is used as a direct-write approach to decorate ultrasmall Pt nanoclusters on carbon nanotubes at selected sites in a straightforward maskless manner. The as-deposited nanostructures are studied by transmission electron microscopy (TEM) in 2D and 3D, demonstrating that the Pt

• nanoclusters are well-dispersed, covering the selected areas of the CNT surface completely. The ability of FEBID to graft nanoclusters on multiple sides, through an electron-transparent target within one step, is unique as a physical deposition method. Using high-resolution TEM we have shown that the CNT

• structure can be well preserved thanks to the low dose used in FEBID. By tuning the electron-beam parameters, the density and distribution of the nanoclusters can be controlled. The purity of as-deposited nanoclusters can be improved by low-energy electron irradiation at room temperature. Keywords: carbon

Directed deposition of silicon nanowires using neopentasilane as precursor and gold as catalyst

• Britta Kämpken,
• Verena Wulf,
• Norbert Auner,
• Marcel Winhold,
• Michael Huth,
• Daniel Rhinow and
• Andreas Terfort

Beilstein J. Nanotechnol. 2012, 3, 535–545, doi:10.3762/bjnano.3.62

• eutectic point of the silicon–gold alloy at 363 °C. However, the best results are achieved at temperatures of 450 °C or higher [19]. Typical deposition methods for the metal include sputtering [20], or its adsorption in the form of nanoclusters [21] or nanoparticles [22]. The sputtering process requires no

Imaging ultra thin layers with helium ion microscopy: Utilizing the channeling contrast mechanism

• Gregor Hlawacek,
• Vasilisa Veligura,
• Stefan Lorbek,
• Tijs F. Mocking,
• Antony George,
• Raoul van Gastel,
• Harold J. W. Zandvliet and
• Bene Poelsema

Beilstein J. Nanotechnol. 2012, 3, 507–512, doi:10.3762/bjnano.3.58

• the formation of cobalt nanoclusters, an atomically clean Ge{001} substrate was obtained by prolonged 800 eV Ar+ ion sputtering followed by annealing of the sample through resistive heating at 1100 K. Several monolayers of Co were evaporated by resistively heating a tungsten wire wrapped with a pure

Structural and magnetic properties of ternary Fe_1–xMn_xPt nanoalloys from first principles

• Markus E. Gruner and
• Peter Entel

Beilstein J. Nanotechnol. 2011, 2, 162–172, doi:10.3762/bjnano.2.20

• concentrations, magnetically inhomogeneous states with antiparallel Mn moments are competitive which are still ferromagnetic at large. Although the antiferromagnetic admixture to a ferromagnetic L10 configuration must be expected to decrease the performance of Fe1–xMnxPt nanoclusters in data recording

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

• explanation for the extraction and deposition of atoms using AFM. In the contact mode, different strategies, such as pushing and pulling, have been used to manipulate nanoclusters. Firstly, the tip can be used for positioning particles on a substrate by pushing or pulling operations [14][15]. For instance