Formation of substrate-based gold nanocage chains through dealloying with nitric acid

• Ziren Yan,
• Ying Wu and
• Junwei Di

Beilstein J. Nanotechnol. 2015, 6, 1362–1368, doi:10.3762/bjnano.6.140

• dealloying reagent to selectively remove Ag atoms from Ag–Au alloy nanoboxes [4][22]. Here, we carried out galvanic replacement reactions on solid-supported Ag nanoparticle templates to form Ag–Au nanocages. Then, the residual Ag in the nanocages was selectively dissolved by chemical etchants. Interestingly

• consistent with the previous report [4]. The chemical reaction involved in the dissolution of Ag at neutral conditions is the following: The deposition of byproducts, such as AgOH or Ag2O, on the particle surface might hinder the complete removal of Ag from the alloy and block up the hole of wall [30

• reported that the concentration of HNO3 is an important parameter because it alters the chemical potential difference across the nanoporous/alloy interface and affects the morphology of Ag–Au alloy during dealloying. Figure 6 exhibits the SEM images of Ag–Au NCs treated with various concentration of HNO3

Heterometal nanoparticles from Ru-based molecular clusters covalently anchored onto functionalized carbon nanotubes and nanofibers

• Deborah Vidick,
• Xiaoxing Ke,
• Michel Devillers,
• Claude Poleunis,
• Arnaud Delcorte,
• Pietro Moggi,
• Gustaaf Van Tendeloo and
• Sophie Hermans

Beilstein J. Nanotechnol. 2015, 6, 1287–1297, doi:10.3762/bjnano.6.133

• elemental analyses, and do not prove that both metals are mixed locally within each nanoparticle. In some other cases, powder XRD proved alloy formation [25], but this is only applicable for crystalline nanoparticles that are usually >3 nm [13][23][29]. In this paper, we explore the possibility of using

Growth and morphological analysis of segmented AuAg alloy nanowires created by pulsed electrodeposition in ion-track etched membranes

• Ina Schubert,
• Loic Burr,
• Christina Trautmann and
• Maria Eugenia Toimil-Molares

Beilstein J. Nanotechnol. 2015, 6, 1272–1280, doi:10.3762/bjnano.6.131

• . For a well-controlled synthesis process, detailed analysis of the deposition parameters and the size-distribution of the segmented wires is crucial. Results: The fabrication of electrodeposited AuAg alloy nanowires and segmented Au-rich/Ag-rich/Au-rich nanowires with controlled composition and segment

• . Additionally, we have dissolved the middle Ag-rich segments in order to create small nanogaps with controlled gap sizes. Annealing of the created structures allows us to influence their morphology. Conclusion: AuAg alloy nanowires, segmented wires and nanogaps with controlled composition and size can be

• synthesised by electrodeposition in membranes, and are ideal model systems for investigation of surface plasmons. Keywords: AuAg alloy; cyclic voltammetry; electrodeposition; ion-track technology; nanogaps; segmented nanowires; Introduction The synthesis of multicomponent heterostructure nanowires is

Addition of Zn during the phosphine-based synthesis of indium phospide quantum dots: doping and surface passivation

• Natalia E. Mordvinova,
• Alexander A. Vinokurov,
• Oleg I. Lebedev,
• Tatiana A. Kuznetsova and
• Sergey G. Dorofeev

Beilstein J. Nanotechnol. 2015, 6, 1237–1246, doi:10.3762/bjnano.6.127

• As a result of synthesis a number of different colored solutions were obtained: yellow, orange and red. It was expected that the addition of excess myristic acid may result in a better stabilization of the QDs if any In(Zn)P alloy could be formed [18], thus enhancing the optical properties of the QDs

Magnetic properties of iron cluster/chromium matrix nanocomposites

• Arne Fischer,
• Robert Kruk,
• Di Wang and
• Horst Hahn

Beilstein J. Nanotechnol. 2015, 6, 1158–1163, doi:10.3762/bjnano.6.117

• precipitate sizes and the width of their distributions, as well as the chemical compositions of the precipitates and the matrix are severely limited by the thermodynamics of the alloy systems. Therefore, in any case the potential of alloy design will remain limited as long as thermo-mechanical treatment is

• clusters of basically any element and many alloy systems and their transfer into an ultra-high vacuum system (UHV). The deposition of the charged clusters onto substrates can be performed with variable impact energies. Such a process opens a new way for the synthesis of cluster-based alloys, i.e

• ., multiphase alloys with extreme control of the fraction of clusters inside a matrix consisting of another element or alloy system. For the alloy system Fe/Ag it has been shown that full control over the overall composition of the two immiscible elements can be achieved [2]. One of the scopes of the

High sensitivity and high resolution element 3D analysis by a combined SIMS–SPM instrument

• Yves Fleming and
• Tom Wirtz

Beilstein J. Nanotechnol. 2015, 6, 1091–1099, doi:10.3762/bjnano.6.110

• spectrometry (SIMS) data was combined with topographical data from the scanning probe microscopy (SPM) module for five test structures in order to obtain accurate chemical 3D maps: a polystyrene/polyvinylpyrrolidone (PS/PVP) polymer blend, a nickel-based super-alloy, a titanium carbonitride-based cermet, a

• of the TiCN cermet. Keywords: alloy; atomic force microscopy (AFM); correlative microscopy; differential sputtering; in situ; multimodal imaging; nano-cluster; polymer blend; secondary ion mass spectrometry (SIMS); scanning probe microscopy (SPM); SIMS artefacts; sputter-induced effects; sputter

• intensity is slightly increased at the position where a dip is present on the PVP dome, which is most likely due to variations of the sputtering yield with the local angle of incidence. Nickel-based super-alloy Differential sputtering can also be observed when analysing nickel-based super-alloys, which are

Tunable magnetism on the lateral mesoscale by post-processing of Co/Pt heterostructures

• Oleksandr V. Dobrovolskiy,
• Maksym Kompaniiets,
• Roland Sachser,
• Fabrizio Porrati,
• Christian Gspan,
• Harald Plank and
• Michael Huth

Beilstein J. Nanotechnol. 2015, 6, 1082–1090, doi:10.3762/bjnano.6.109

• , though acquired with a statistical error of 3%, the EDX data in Table 1 only serve as an indicator of the Co/Pt ratio being crucial for the different Co/Pt alloy phase formation — an issue to which we return in what follows. The temperature dependence of the electrical resistance of all samples is

• Figure 2. As will be shown below by TEM, it is this nanoporosity which allows Co to penetrate into the Pt layer during the Co deposition and to form a Co/Pt alloy phase. Considering the Co–Pt binary phase diagram [47], for a Co/Pt-ratio of 1:1, the CoPt L10 phase can form. This phase is a hard

Effects of swift heavy ion irradiation on structural, optical and photocatalytic properties of ZnO–CuO nanocomposites prepared by carbothermal evaporation method

• Sini Kuriakose,
• D. K. Avasthi and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2015, 6, 928–937, doi:10.3762/bjnano.6.96

• irradiated at fluences of 3 × 1013 and 1 × 1014 ions/cm2 are estimated to be 14.2 nm, 14.6 nm and 15.7 nm, respectively. It can be clearly seen that the average crystallite size of ZnO increases with increase in ion fluence. In addition to ZnO and CuO, nanostructured Cu–Zn alloy, Cu5Zn8 [JCPDS no. 71-0397

• ] were also observed, as can be seen from Figure 2. The Cu–Zn alloy is more prominently seen in the case of pristine sample. In the swift heavy ion irradiated samples the peaks corresponding to Cu–Zn alloy nanoparticles get increasingly diminished in intensity with increase in fluence. The UV–visible

• evaporation of ZnO and Cu, combined with annealing. FESEM studies showed the presence of ZnO nanosheets and nanorods, which are formed by Cu–Zn alloy nanodroplets assisted oriented attachment of ZnO nanoparticles. The effects of swift heavy ion irradiation on the structural, optical, and photocatalytic

Mapping of elasticity and damping in an α + β titanium alloy through atomic force acoustic microscopy

• M. Kalyan Phani,
• Anish Kumar,
• T. Jayakumar,
• Walter Arnold and
• Konrad Samwer

Beilstein J. Nanotechnol. 2015, 6, 767–776, doi:10.3762/bjnano.6.79

• . Physikalisches Institut, Georg-August-Universität, Friedrich Hund Platz 1, D-37077 Göttingen, Germany 10.3762/bjnano.6.79 Abstract The distribution of elastic stiffness and damping of individual phases in an α + β titanium alloy (Ti-6Al-4V) measured by using atomic force acoustic microscopy (AFAM) is reported

• cantilever with damped flexural modes. The cantilever dynamics model considering damping, which was proposed recently, has been used for mapping of indentation modulus and damping of different phases in a metallic structural material. The study indicated that in a Ti-6Al-4V alloy the metastable β phase has

• GPa. The type and amount of various phases formed during thermal/thermo-mechanical treatments influence both the mechanical as well as the elastic properties of α + β titanium alloys [1]. By varying the volume fractions of the two phases present in the alloy, various combinations of strength and

Influence of gold, silver and gold–silver alloy nanoparticles on germ cell function and embryo development

• Ulrike Taylor,
• Daniela Tiedemann,
• Christoph Rehbock,
• Wilfried A. Kues,
• Stephan Barcikowski and
• Detlef Rath

Beilstein J. Nanotechnol. 2015, 6, 651–664, doi:10.3762/bjnano.6.66

• fertility parameters deteriorated after co-incubation with ligand free gold nanoparticles. However, the effect could be alleviated by bio-coating the nanoparticles, which even applies to silver and silver-rich alloy nanoparticles. The most sensitive test system appeared to be in vitro oocyte maturation

• showing a dose-dependent response towards protein (BSA) coated gold–silver alloy and silver nanoparticles leading up to complete arrest of maturation. Recent biodistribution studies confirmed that nanoparticles gain access to the ovaries and also penetrate the blood–testis and placental barrier. Thus, the

• to nanoscale particles”. The aim was to study the impact of gold and silver nanoparticles, and to a degree gold–silver alloy nanoparticles, on spermatozoa, oocytes and embryos in vitro using murine as well as bovine and porcine models (Figure 1) [49][50][51]. The nanoparticles used in our studies

Influence of grain size and composition, topology and excess free volume on the deformation behavior of Cu–Zr nanoglasses

• Daniel Şopu and
• Karsten Albe

Beilstein J. Nanotechnol. 2015, 6, 537–545, doi:10.3762/bjnano.6.56

• properties of Cu–Zr nanoglasses (NGs) is investigated by molecular dynamics simulations using two model glasses of different alloy composition, namely Cu64Zr36 (Cu-rich) and Cu36Zr64 (Zr-rich). When the grain size is increased, or the fraction of interfaces in these NGs is decreased, we find a transition

• investigate if the plastic behavior of NGs changes with glass composition. Finally, the impact of the thermal relaxation of the glass–glass interface is studied. For this, two model glasses of different alloy composition are used, namely Cu64Zr36 (Cu-rich) and Cu36Zr64 (Zr-rich). All simulations are carried

• -centered FI [0,0,12,0] because this polyhedron is known to be the key structural motif in amorphous Cu–Zr alloy, characterized by a high packing density [21] and high shear resistance [22]. For modeling the NG microstructure, a 2D array of columnar grains with a hexagonal cross section is used. The grains

Filling of carbon nanotubes and nanofibres

• Reece D. Gately and
• Marc in het Panhuis

Beilstein J. Nanotechnol. 2015, 6, 508–516, doi:10.3762/bjnano.6.53

• within the core of a filled MWCNT. This was achieved by first filling a MWCNT with iron, cobalt, nickel, or an iron–cobalt alloy using capillary action. Following this step, the sample was placed inside a transmission electron microscope (with the sample stage temperature set at 600 °C) and subjected to

Electrical properties of single CdTe nanowires

• Elena Matei,
• Camelia Florica,
• Andreea Costas,
• María Eugenia Toimil-Molares and
• Ionut Enculescu

Beilstein J. Nanotechnol. 2015, 6, 444–450, doi:10.3762/bjnano.6.45

• a well-established method of plating conductive substrates with a specific metal or alloy. During the last decades, semiconductor electrodeposition became more and more attractive, as it may represent a viable alternative to more expensive fabrication methods [14][15][16]. CdTe electroplating is an

Materials and characterization techniques for high-temperature polymer electrolyte membrane fuel cells

• Roswitha Zeis

Beilstein J. Nanotechnol. 2015, 6, 68–83, doi:10.3762/bjnano.6.8

• . To reduce the noble-metal loading of a fuel cell, platinum alloy catalysts such as PtNi and PtCo may be used. However, the stability of these Pt alloy catalysts is questionable partially because, under fuel cell operating conditions, transition metals such as nickel and cobalt are expected to form

• oxides or hydroxides that tend to dissolve from the electrode surface. Nevertheless, carbon-supported platinum/transition metal alloy catalysts are often used in conventional LT-PEMFCs as well as PAFCs. There is strong experimental evidence that platinum alloys outperform pure platinum catalysts [41][42

• the interatomic Pt–Pt distance [43]. Other researchers have suggested that the alloy layer beneath the platinum skin increases the d-band vacancy of the platinum itself improving, therefore, the oxygen reduction reaction [20]. A great deal of research on this subject was carried out from 1970’s until

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

• having an Orsay Physics mass filtered ion column operated at 30 keV. A liquid metal alloy ion source (LMAIS) of Au4Si ([Si] = 19%, [Au] = 81%) heated at 450 °C was used for the milling step; a Au2+ or Si+ ion beam was selected independently by a Wien filter. The patterns in the Si/SiO2 substrate were

• transformation from the small Au nanoclusters located within the SiO2-cover-free nanopits to the Au0.18Si0.82 eutectic alloy is obtained by thermal annealing at 550 °C for 30 min. The annealing and growth experiments were performed in the MBE growth chamber of a Riber SIVA32 system with a base pressure of 10−11

• volume of 0.006 µm3) and thus the carriers have to be recombining efficiently within the wires to produce this light emission at the SiGe-alloy band gap energy. We know from earlier studies of SiGe etched wires [32] and dots [33] that just the spatial confinement of carriers is sufficient to produce the

Si/Ge intermixing during Ge Stranski–Krastanov growth

• Alain Portavoce,
• Khalid Hoummada,
• Antoine Ronda,
• Dominique Mangelinck and
• Isabelle Berbezier

Beilstein J. Nanotechnol. 2014, 5, 2374–2382, doi:10.3762/bjnano.5.246

• minimization of the surface energy, the strain energy, the alloy mixing energy and the configurational entropy [22]. In the case of a pure Ge dome island (no intermixing with Si), the stress was shown to be compressive in the interior of the island, and tensile at the edges of the island [34]. Thus, in the

Biopolymer colloids for controlling and templating inorganic synthesis

• Laura C. Preiss,
• Katharina Landfester and
• Rafael Muñoz-Espí

Beilstein J. Nanotechnol. 2014, 5, 2129–2138, doi:10.3762/bjnano.5.222

• ] demonstrated the synthesis of iron oxide nanoparticles in a semi-interpenetrating polymer network of alginate and poly(N-isopropylacrylamide). Gold and AuNi alloy gelatin nanocomposites were developed by Brayner et al. [84]. A gelatin network incorporating metallic nanoparticles was obtained after reduction of

• supercritical CO2 and subsequent calcination. Scaffold templating can also be achieved with starch and even with peptides. Thakore et al. [13] synthesized Cu, Ag, and Cu–Ag alloy nanoparticles in a matrix of starch through a green route and studied the antibacterial activity. Hexagonal silica platelets were

Carbon nano-onions (multi-layer fullerenes): chemistry and applications

• Juergen Bartelmess and
• Silvia Giordani

Beilstein J. Nanotechnol. 2014, 5, 1980–1998, doi:10.3762/bjnano.5.207

• fluorescent-tagged CNOs (Scheme 8) were then used for in vitro fluorescence imaging, which will be discussed in the corresponding section of this review article. Recently, Echegoyen et al. reported for the first time the alkylation of CNOs [42], which was achieved by a reductive process utilizing a Na–K alloy

• . CNOs were added to a previously prepared, deep-blue solution of the Na–K alloy in 1,2-dimethoxyethane under inert atmosphere affording a brownish dispersion. Then an excess of 1-bromohexadecane was added as electrophile and the alkylated CNO material (CNO-C16) could be recovered. TGA analysis and IR as

The impact of the confinement of reactants on the metal distribution in bimetallic nanoparticles synthesized in reverse micelles

• Concha Tojo,
• Elena González and
• Nuria Vila-Romeu

Beilstein J. Nanotechnol. 2014, 5, 1966–1979, doi:10.3762/bjnano.5.206

• than the other, it will form the core. The metal which is reduced more slowly will be deposited onto this core, forming the outer layers, which results in a core–shell nanostructure. In contrast, a small difference between reduction rates of the two metals leads to an alloy. Third, this result was

Cathode lens spectromicroscopy: methodology and applications

• T. O. Menteş,
• G. Zamborlini,
• A. Sala and
• A. Locatelli

Beilstein J. Nanotechnol. 2014, 5, 1873–1886, doi:10.3762/bjnano.5.198

• , Fe preferentially wets the Pd-covered parts of the striped template. Furthermore, at about 200 °C Fe and Pd rearrange to make a surface alloy with a Pd-rich surface layer. The magnetization of the FePd stripes was found to be along the direction perpendicular to the stripe axis, as shown in the XMCD

On the structure of grain/interphase boundaries and interfaces

• K. Anantha Padmanabhan and
• Herbert Gleiter

Beilstein J. Nanotechnol. 2014, 5, 1603–1615, doi:10.3762/bjnano.5.172

• deformation in micro-grained and nanostructured pseudo-single phase as well as micro-duplex metallic materials, ceramics, ceramic composites, intermetallics, dispersion strengthened alloys and an alloy containing quasi-crystalline particles [53]. Very recently, it has been found to be useful for interpreting

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• paragraph of this article highlights the recent progress concerning the synthesis of composition controlled alloy nanoparticles by laser ablation in liquids. Here, binary and ternary alloy nanoparticles with totally homogeneous elemental distribution could be fabricated and the composition of these

• particles closely resembled bulk implant material. Finally, the model AuAg was used to systematically evaluate composition related toxicological effects of alloy nanoparticles. Here Ag+ ion release is identified as the most probable mechanism of toxicity when recent toxicological studies with gametes

• , mammalian cells and bacteria are considered. Keywords: albumin; gold-silver; implant alloy; laser ablation; nickel-titanium; size control; wear debris; Introduction The widespread use of medical implants consisting of metals (e.g., gold coatings [1]) and alloys (e.g., NiTi, CoCr, stainless steel) [2][3][4

Liquid fuel cells

• Grigorii L. Soloveichik

Beilstein J. Nanotechnol. 2014, 5, 1399–1418, doi:10.3762/bjnano.5.153

• alloy increases the reaction rate by more than one order of magnitude compared to pure Pt supposedly due to the formation of hydrous molybdenum oxide that reduces the surface poisoning by adsorbed CO [130]. Palladium-based electrocatalysts deliver higher power densities compared to platinum-based ones

• on carbon was comparable [157]. Nickel-0based electrocatalysts are the most active for hydrazine oxidation. An alloy with the composition Ni0.6Co0.4 was about 6 times more active than the pure Ni catalyst [155]. The design space of binary Ni–M (with M = Mn, Fe, Zn, La) and ternary Ni–Mn–Fe and Ni–Zn

• reduces the cell efficiency and poisons the cathode catalyst. A fuel cell with a Laves phase AB2 Zr–Ni based alloy and Pd/C as the anode catalyst, a Nafion® NRE-211 membrane and Pt/C as the cathode catalyst delivered a power density of 290 mW/cm2 at 60 °C [172]. The NaBH4 utilization was only 51% but

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

• randomly in the Cu lattice. A novel simulation method is applied to study the growth mechanism, which shows the formation of alloy structures in good agreement with the experimental evidence. The findings give insight into the formation mechanism of the nanosized Cu–Pt bimetallic catalysts. Keywords: Cu

• , heterostructures, and alloy nanocrystals, and this diversity potentiates the increase of the mass specific activity (MSA) of the nanoparticle while also minimizing the cost by using precious metals only in the surface of the particles. Thus, in order to attain a better control on shape, size and composition of the

• 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

Magnesium batteries: Current state of the art, issues and future perspectives

• Rana Mohtadi and
• Fuminori Mizuno

Beilstein J. Nanotechnol. 2014, 5, 1291–1311, doi:10.3762/bjnano.5.143