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

• , the Si substrate PL becomes sufficiently quenched from the increasing dissociation of multiple-donor bound excitons within the substrate [31] that the underlying NW PL is more readily seen. By 25 K, only the sharp line at 1092.5 meV due to the Si substrate remains. From now on we shall consider only

Gas sensing properties of nanocrystalline diamond at room temperature

• Marina Davydova,
• Pavel Kulha,
• Alexandr Laposa,
• Karel Hruska,
• Pavel Demo and
• Alexander Kromka

Beilstein J. Nanotechnol. 2014, 5, 2339–2345, doi:10.3762/bjnano.5.243

• electrolytic dissociation of the gases in the H-terminated diamond layer [3]. Cold plasma microwave PECVD system In the following experiments, the fully-integrated sensor device on a micro-hotplate was used. In contrast to hot plasma, where the plasma is localized close to the substrate surface (i.e., a

Spectroscopic mapping and selective electronic tuning of molecular orbitals in phosphorescent organometallic complexes – a new strategy for OLED materials

• Pascal R. Ewen,
• Jan Sanning,
• Tobias Koch,
• Nikos L. Doltsinis,
• Cristian A. Strassert and
• Daniel Wegner

Beilstein J. Nanotechnol. 2014, 5, 2248–2258, doi:10.3762/bjnano.5.234

• between the Pt atom and the AL. This may occur when a molecule diffuses to an elbow site of the Au(111) herringbone reconstruction or a monatomic step edge, where the Au atoms have a lower coordination and hence interact stronger with adsorbates. At higher coverages, diffusion (and thus dissociation) is

• charge-injection barriers and the HOMO–LUMO gap, and hence the emission color, independently. We will perform further investigations on this matter to test the validity of this concept. Conclusion We showed that various phosphorescent Pt(II) complexes can be deposited reliably and without dissociation

Modification of a single-molecule AFM probe with highly defined surface functionality

• Fei Long,
• Bin Cao,
• Ashok Khanal,
• Shiyue Fang and
• Reza Shahbazian-Yassar

Beilstein J. Nanotechnol. 2014, 5, 2122–2128, doi:10.3762/bjnano.5.221

• stretching the molecule from the entropic form to the extended form. Also, intermolecular interactions could be investigated by attaching one molecule to a probe and the other to a substrate. Examples include the unfolding of proteins [8][9], dissociation of receptors from ligands [10][11], and un-zipping

Effects of surface functionalization on the adsorption of human serum albumin onto nanoparticles – a fluorescence correlation spectroscopy study

• Pauline Maffre,
• Stefan Brandholt,
• Karin Nienhaus,
• Li Shang,
• Wolfgang J. Parak and
• G. Ulrich Nienhaus

Beilstein J. Nanotechnol. 2014, 5, 2036–2047, doi:10.3762/bjnano.5.212

• supernatant and, therefore, are only sensitive to strongly bound proteins, having dissociation rates longer than the experimental time scale [54]. To probe reversibility, we have measured the hydrodynamic radius, RH, of DHLA–QDs by using FCS. Subsequently, we have incubated the NPs with protein at a

Electronic and electrochemical doping of graphene by surface adsorbates

• Hugo Pinto and
• Alexander Markevich

Beilstein J. Nanotechnol. 2014, 5, 1842–1848, doi:10.3762/bjnano.5.195

• through SiO2 at room temperature [44]. Therefore, the concentration of OH− at the graphene/SiO2 interface and thus the rate of the reaction is influenced by the gate voltage. A positive Vg results in the reduction of the OH− concentration at the graphene interface promoting the further dissociation of H2O

In vitro and in vivo interactions of selected nanoparticles with rodent serum proteins and their consequences in biokinetics

• Wolfgang G. Kreyling,
• Stefanie Fertsch-Gapp,
• Martin Schäffler,
• Blair D. Johnston,
• Nadine Haberl,
• Christian Pfeiffer,
• Jörg Diendorf,
• Carsten Schleh,
• Stephanie Hirn,
• Manuela Semmler-Behnke,
• Matthias Epple and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1699–1711, doi:10.3762/bjnano.5.180

• with lipopolysaccharide (LPS) as a simple model for a bacterial infection. In vivo pre-exposure of NP to the lungs leads to rapid clearance of the NP out of the conducting airways and the dissolution/dissociation of NP, but also to formation of the protein corona and numerous cellular interactions

• discrepancy suggests that the Ag dissociation during aging of the AgNP suspension is more complex than just forming Ag+ ions. Conclusion Upon contact with body fluids such as blood serum NP bind soluble proteins according to their physicochemical surface properties and the protein affinity and/or the

Donor–acceptor graphene-based hybrid materials facilitating photo-induced electron-transfer reactions

• Anastasios Stergiou,
• Georgia Pagona and
• Nikos Tagmatarchis

Beilstein J. Nanotechnol. 2014, 5, 1580–1589, doi:10.3762/bjnano.5.170

• fluorescence quenching of the coumarin moiety. However, fluorescence is activated (on) and significantly enhanced inside the cells by glutathione-initiated dissociation. Donor–acceptor hybrids based on exfoliated graphene However, as mentioned earlier, the surface defects in the sp2-network of GO influence the

In vitro interaction of colloidal nanoparticles with mammalian cells: What have we learned thus far?

• Moritz Nazarenus,
• Qian Zhang,
• Mahmoud G. Soliman,
• Pablo del Pino,
• Beatriz Pelaz,
• Susana Carregal-Romero,
• Joanna Rejman,
• Barbara Rothen-Rutishauser,
• Martin J. D. Clift,
• Reinhard Zellner,
• G. Ulrich Nienhaus,
• James B. Delehanty,
• Igor L. Medintz and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1477–1490, doi:10.3762/bjnano.5.161

• " corona [144][145]. The initial, soft corona is formed by the most abundant proteins, which are then replaced by the high-affinity proteins to yield the hard corona. It has been suggested that differences for different protein species can be characterized by their dissociation constants [30]. In a simple

• model the dissociation constant tells which protein concentration is required to saturate half of the NP surface with proteins under equilibrium conditions [30]. With simple treatments such as the Hill Model [146] one may characterize the protein corona around NPs with only a few parameters, which would

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

• extent of salt dissociation. The substantial improvements in the electrochemical performance as the dendicity of the solvent was increased, and following the addition of LiBH4, used as a source of a Lewis acid cation, further supported this hypothesis. In the case of the amidomagnesium (HMDS) based

Effects of palladium on the optical and hydrogen sensing characteristics of Pd-doped ZnO nanoparticles

• Anh-Thu Thi Do,
• Hong Thai Giang,
• Thu Thi Do,
• Ngan Quang Pham and
• Giang Truong Ho

Beilstein J. Nanotechnol. 2014, 5, 1261–1267, doi:10.3762/bjnano.5.140

• the gas sensing response characteristics allows us to suggest that the dissociation of hydrogen takes place at PdZn-vacancies ([Pd 2+(4d9)]). The design of this sensor allows for a continuous monitoring in the range of 0–100% LEL H2 concentration with high sensitivity and selectivity. Keywords

• response characteristics of these samples. We suggest that the dissociation of hydrogen takes place at PdZn-vacancies (i.e, [Pd2+(4d9)]) and may be expressed as, Then, the oxidation of dissociated hydrogen happens according to the reaction, Similar results, viz. that the concentration of vacancies in turn

• level emission and the gas sensing response characteristics of these samples. We suggest that the dissociation of hydrogen takes place at PdZn-vacancies ([Pd2+(4d9)]). The design of sensors as a catalytic membrane and Wheatstone bridge measurements allow for the continuous monitoring of the H2

An insight into the mechanism of charge-transfer of hybrid polymer:ternary/quaternary chalcopyrite colloidal nanocrystals

• Parul Chawla,
• Son Singh and
• Shailesh Narain Sharma

Beilstein J. Nanotechnol. 2014, 5, 1235–1244, doi:10.3762/bjnano.5.137

• polymer and acceptor chalcopyrite has to be sufficiently fast to their respective electrodes in order to avoid non-radiative recombination, which can occur at the interface between the two materials and can therefore alter the device photocurrent [24]. However, after successful exciton dissociation across

Electron-beam induced deposition and autocatalytic decomposition of Co(CO)₃NO

• Florian Vollnhals,
• Martin Drost,
• Fan Tu,
• Esther Carrasco,
• Andreas Späth,
• Rainer H. Fink,
• Hans-Peter Steinrück and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2014, 5, 1175–1185, doi:10.3762/bjnano.5.129

• EBID, suitable precursor molecules are dosed onto a surface and then decomposed by the focused electron beam of a scanning electron microscope (SEM) or a transmission electron microscope (TEM). The volatile precursor fragments are pumped off by the vacuum system, while the non-volatile dissociation

• of active sites for the initial decomposition of Co(CO)3NO. The nature of the active site cannot be deduced from the available data, but we assume that upon adsorption of the Co(CO)3NO precursor on the clean Fe film the immediate dissociation of the precursor takes place. In order to gain more

Pyrite nanoparticles as a Fenton-like reagent for in situ remediation of organic pollutants

• Carolina Gil-Lozano,
• Elisabeth Losa-Adams,
• Alfonso F.-Dávila and
• Luis Gago-Duport

Beilstein J. Nanotechnol. 2014, 5, 855–864, doi:10.3762/bjnano.5.97

• have reported that pyrite can spontaneously produce H2O2 via catalytic dissociation of O2 and H2O with iron surface sites [7][8][10][12][13][14]. Albeit the use of pyrite alone as Fenton reagent (i.e., without externally added H2O2) has been demonstrated for lactate degradation [15], this approach

Adsorption and oxidation of formaldehyde on a polycrystalline Pt film electrode: An in situ IR spectroscopy search for adsorbed reaction intermediates

• Zenonas Jusys and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2014, 5, 747–759, doi:10.3762/bjnano.5.87

• , including water molecules and the electrode potential, implied that methanol dehydrogenation to COad via a hydroxymethyl intermediate (initial C–H bond dissociation) is the lowest energy path, whereas the formation of a formaldehyde intermediate (initial C–H bond dissociation) is a minority pathway on a Pt

• dissociative adsorption to form COad even at low potentials, e.g., via displacement of Hupd. At 0.4 V, where there is no more Hupd blocking, methylene glycol can also dissociatively adsorb to form COad, via dissociation of two C–H bonds, assuming that it behaves similarly as other alcohols [45][46][47][48][60

• ][61]. In addition, however, it could be oxidized to formic acid, which requires dissociation of a single C–H bond only, in an apparently facile dehydrogenation step. Similar trends were also reported for the competing adsorption of formaldehyde and methanol using mixtures of carbon-labelled

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

• at 95 °C followed by 43 cycles of 95 °C for 15 s and the appropriate annealing temperature given in Table 3 for 1 min and finally heating with a ramp rate of 2%: 95 °C for 15 s, 60 °C for 15 s and 95 °C for 15 s to display a dissociation curve of the product (ABI 7500 Fast Real-Time System, Applied

Mesoporous cerium oxide nanospheres for the visible-light driven photocatalytic degradation of dyes

• Subas K. Muduli,
• Songling Wang,
• Shi Chen,
• Chin Fan Ng,
• Cheng Hon Alfred Huan,
• Tze Chien Sum and
• Han Sen Soo

Beilstein J. Nanotechnol. 2014, 5, 517–523, doi:10.3762/bjnano.5.60

• , and solar thermal dissociation of water and CO2 [14][15][16][17][18]. Cerium oxides with oxygen vacancies represent an underexplored area of nanotechnology with the potential to provide visible-light absorbing photocatalysts [13][19][20][21]. Cerium is relatively earth-abundant and the oxides

Confinement dependence of electro-catalysts for hydrogen evolution from water splitting

• Mikaela Lindgren and
• Itai Panas

Beilstein J. Nanotechnol. 2014, 5, 195–201, doi:10.3762/bjnano.5.21

• hydrogen evolution activity in water splitting by tailoring TM(OH)2-Pt electro-catalyst/electrode assemblies, where TM represents Mn2+, Fe2+, Co2+ and Ni2+. The role of these hydroxides was to catalyze water dissociation. In this context, the objective of the present study is to contribute a novel

• clearly points to the noble metal ions as candidates for electro-catalysts. Additional requirements for any successful electro-catalyst include sufficient electron conductivity of the oxide matrix supporting the catalyst as well as electric contact to the electrode itself. Finally, the "water dissociation

Fabrication of carbon nanomembranes by helium ion beam lithography

• Xianghui Zhang,
• Henning Vieker,
• André Beyer and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2014, 5, 188–194, doi:10.3762/bjnano.5.20

• conducted by exposure to electrons [10] and photons [11]. Electron irradiation induces the dissociation of C–H bonds at the phenyl rings. The consequent cross-linking between adjacent aromatic moieties is a critical step in the formation of CNMs. Both electron beam lithography and extreme ultraviolet (EUV

• [29]. These breaks are attributed to the DEA process, in which the attachment of incident electrons leads to the formation of a transient molecular anion (TMA) state and this TMA decays by electron autodetachment or by dissociation of a specific bond. The probability of forming a TMA, i.e., the

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

• dissociation barriers (1.8 eV) of N2 not taking place at the surface. For the purposes of analyzing the reduction of oxygen, a two-step electron-transfer process was assumed and simulated using the Heyrovsky-type [19] reaction. In an acidic environment, the reaction comprises of these elementary reaction steps

Some reflections on the understanding of the oxygen reduction reaction at Pt(111)

• Ana M. Gómez-Marín,
• Ruben Rizo and
• Juan M. Feliu

Beilstein J. Nanotechnol. 2013, 4, 956–967, doi:10.3762/bjnano.4.108

• suggested by the reported experimental results discussed above [18]. Recent theoretical calculations, which consider explicitly the effect of a bulk water layer on the mechanism of the ORR, have suggested that the dissociation of OOHads, Equation 6, is much less favorable on the water covered surface as

In situ growth optimization in focused electron-beam induced deposition

• Paul M. Weirich,
• Marcel Winhold,
• Christian H. Schwalb and
• Michael Huth

Beilstein J. Nanotechnol. 2013, 4, 919–926, doi:10.3762/bjnano.4.103

• of the procedure is presented for the precursor W(CO)6 as well as for post-treatment of Pt–C deposits, which were obtained by the dissociation of MeCpPt(Me)3. For W(CO)6-based structures an increase of conductivity by one order of magnitude can be achieved, whereas the effect for MeCpPt(Me)3 is

• , can be a difficult task. This can be exemplified for the commonly used precursor W(CO)6. Rosenberg and co-workers recently studied the electron-dose and substrate-temperature dependence on the final deposit in electron-induced dissociation experiments with 500 eV electron energy for this precursor [14

• ][15]. They showed that the initial dissociation at electron doses below about 100 pC/μm2 leads to the release (i.e., dissociation and desorption) of two CO ligands from the parent molecule. The decarbonylated residual species is then subject to an electron-stimulated decomposition rather than to a

Energy transfer in complexes of water-soluble quantum dots and chlorin e6 molecules in different environments

• Irina V. Martynenko,
• Anna O. Orlova,
• Vladimir G. Maslov,
• Alexander V. Baranov,
• Anatoly V. Fedorov and
• Mikhail Artemyev

Beilstein J. Nanotechnol. 2013, 4, 895–902, doi:10.3762/bjnano.4.101

• of the etching, carboxyl groups are produced on the interior surface and in the loosened layer nearby the pore wall. The dissociation of the carboxyl groups in aqueous solutions leads to the appearance of negative charges on the track pore surface [11]. This gives the opportunity to passivate the

• and their tendency to dissociation, they are supposed to be good model objects to explore the dependencies of FRET efficiency and Ce6 QY on n in the complexes by spectral luminescence methods. The samples for studies were prepared by stepwise increasing the Ce6 concentration in solution of QD and Ce6

Simulation of electron transport during electron-beam-induced deposition of nanostructures

• Francesc Salvat-Pujol,
• Harald O. Jeschke and
• Roser Valentí

Beilstein J. Nanotechnol. 2013, 4, 781–792, doi:10.3762/bjnano.4.89

• the curves corresponding to the (thick) deposit and the substrate. Thus, under the assumption that the presence of a large number of electrons (slow or fast) enhances the dissociation rate of the precursor gas molecules adsorbed on the substrate, one can infer the following positive-feedback process

• : As the deposit thickness grows, so does the number of backscattered and emitted electrons, leading to an improvement in the dissociation rate and, therefore, in the deposition rate of the nanostructure, which in turn leads to a reinforced growth process. A more quantitative description of the change

• to an enhancement of the dissociation of the precursor gas molecules adsorbed on the surface. It is therefore worthwhile to have an accurate estimate for this quantity. The consequences for the growth of the nanostructures are an interesting topic for further research. Conclusion In this work we

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

• form superoxide anion radicals (•O2−) (Equation 6). The holes generated in the valence band of ZnO react with surface hydroxy groups to produce highly reactive hydroxyl (•OH) radicals (Equation 7). The photogenerated holes can lead to the production of •OH radicals through the dissociation of water