Modelling focused electron beam induced deposition beyond Langmuir adsorption

• Dédalo Sanz-Hernández and
• Amalio Fernández-Pacheco

Beilstein J. Nanotechnol. 2017, 8, 2151–2161, doi:10.3762/bjnano.8.214

• using the data in the maps. To start, Figure 3a shows a paradigmatic example studied in FEBID: The transition from the mass-transport-limited (MTL) to the reaction-rate limited (RRL) regime at constant temperature [1][2][3] and Langmuir adsorption. The figure shows how RRL is found at high precursor

• heterogeneous multilayer adsorption conditions. We have identified three fundamental FEBID regimes, corresponding to mass-transport limited, reaction-rate limited and desorption-dominated conditions. Moreover, we extract and classify the types of FEBID isotherms described by these models, finding four types of

Fabrication of hierarchically porous TiO₂ nanofibers by microemulsion electrospinning and their application as anode material for lithium-ion batteries

• Jin Zhang,
• Yibing Cai,
• Xuebin Hou,
• Xiaofei Song,
• Pengfei Lv,
• Huimin Zhou and
• Qufu Wei

Beilstein J. Nanotechnol. 2017, 8, 1297–1306, doi:10.3762/bjnano.8.131

• ] that have advantages over normal structures including a large specific surface area, a high electrolyte–electrode contact area and excellent mass transport of products or reactants to active sites inside meso- or micropores. One-dimensional (1D) nanostructures such as nanofibers, nanotubes, nanowires

Structural properties and thermal stability of cobalt- and chromium-doped α-MnO₂ nanorods

• Romana Cerc Korošec,
• Polona Umek,
• Alexandre Gloter,
• Jana Padežnik Gomilšek and
• Peter Bukovec

Beilstein J. Nanotechnol. 2017, 8, 1032–1042, doi:10.3762/bjnano.8.104

• improved the electrical conductivity, while nanoflakes and the secondary structure increase the specific surface area, leading to improved electrode kinetics by facilitating mass transport [24]. However, there is a lack of detailed structural studies of these materials in order to understand why cobalt as

Evidence for non-conservative current-induced forces in the breaking of Au and Pt atomic chains

• Carlos Sabater,
• Carlos Untiedt and
• Jan M. van Ruitenbeek

Beilstein J. Nanotechnol. 2015, 6, 2338–2344, doi:10.3762/bjnano.6.241

• periodic orbits. This so-called ‘Berry force’ has never been demonstrated in experiment. In fact, also the first component of the non-equilibrium force is only known from electromigration experiments that detect mass transport of atoms or ions. Truly microscopic experiments probing the forces at the scale

A single-source precursor route to anisotropic halogen-doped zinc oxide particles as a promising candidate for new transparent conducting oxide materials

• Daniela Lehr,
• Markus R. Wagner,
• Johanna Flock,
• Julian S. Reparaz,
• Clivia M. Sotomayor Torres,
• Alexander Klaiber,
• Thomas Dekorsy and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2015, 6, 2161–2172, doi:10.3762/bjnano.6.222

• material [41][42][43]. They are very reactive, guarantee a high mass transport and can be converted into the solid material at relatively low temperatures. Whereas a substantial number of MSSPs for binary materials are known, there are only few examples for ternary phases as targets [44][45][46]. Our group

Nonconservative current-driven dynamics: beyond the nanoscale

• Brian Cunningham,
• Tchavdar N. Todorov and
• Daniel Dundas

Beilstein J. Nanotechnol. 2015, 6, 2140–2147, doi:10.3762/bjnano.6.219

• current carriers into atomic motion. Large current densities can generate significant additional forces on atomic nuclei [1][2][3], resulting in a class of phenomena known as electromigration: atomic rearrangements and mass transport driven by current flow [4][5]. Recent work has drawn attention to

Comprehensive characterization and understanding of micro-fuel cells operating at high methanol concentrations

• Aldo S. Gago,
• Juan-Pablo Esquivel,
• Neus Sabaté,
• Joaquín Santander and
• Nicolas Alonso-Vante

Beilstein J. Nanotechnol. 2015, 6, 2000–2006, doi:10.3762/bjnano.6.203

• the cathode potential. Information about the open circuit potential (OCP), the voltage and the mass transport related phenomena are available. Using 2 M CH3OH, the anode showed mass transport problems. With 4 and 6 M CH3OH both electrodes experience this situation, whereas with 10 and 20 M CH3OH the

• cell is limited. Moreover, CO2 bubbles and formation of H2O contribute to this difficulty. While this problem can be partially overcome with an optimal design of micro-fabricated current collectors [11], the effects of fuel crossover and mass transport in this micro-system are still not clear [12][13

• contribute to this negative effect. With 10 and 20 M CH3OH the mass transport issues are inverted with the cathode being responsible for the low performance. The latter is flooded by the fuel that crosses through the membrane limiting the accessibility of O2 to the active Pt sites. The potential at the

Surface engineering of nanoporous substrate for solid oxide fuel cells with atomic layer-deposited electrolyte

• Sanghoon Ji,
• Waqas Hassan Tanveer,
• Wonjong Yu,
• Sungmin Kang,
• Gu Young Cho,
• Sung Han Kim,
• Jihwan An and
• Suk Won Cha

Beilstein J. Nanotechnol. 2015, 6, 1805–1810, doi:10.3762/bjnano.6.184

• electrochemically characterized with varying thickness of bottom electrode catalyst (BEC); BECs which are 0.5 and 4 times thicker than the size of AAO pores are tested. The thicker BEC ensures far more active mass transport on the BEC side and resultantly the thicker BEC cell generates ≈11 times higher peak power

• density than the thinner BEC cell at 500 °C. Keywords: anodic aluminum oxide; atomic layer deposition; bottom electrode catalyst; mass transport; solid oxide fuel cell; Introduction Recently solid oxide fuel cells with thin film ceramic electrolytes, called thin film solid oxide fuel cells (TF-SOFCs

• , and the thicknesses of BECs are smaller or larger than the size of AAO pores. Although the 320 nm-thick BEC cell has slightly worse reaction kinetics, compared to the 40 nm-thick BEC cell, its peak power density is approximately 11 times higher due to far more active mass transport on the BEC side

Continuum models of focused electron beam induced processing

• Milos Toth,
• Charlene Lobo,
• Vinzenz Friedli,
• Aleksandra Szkudlarek and
• Ivo Utke

Beilstein J. Nanotechnol. 2015, 6, 1518–1540, doi:10.3762/bjnano.6.157

• the molecular properties of each adsorbate and the electron flux profile(s) at the solid–vacuum interface. Simple continuum FEBIP models can be solved analytically, yielding governing laws delineating the so-called “reaction-rate” and “mass transport” limited process regimes, and resolution scaling

• and chemisorbed precursor molecules, gas mixtures, and multiple reaction products. Finally, we cover a number of models that account for surface diffusion and can be used to model FEBIP in both the reaction and mass transport limited regimes. Throughout, we emphasize the underlying assumptions and

• reaction rate limited growth is that the electron-induced dissociation rate is much smaller than the sum of the adsorption rate and the thermal desorption rate, i.e., using the symbols defined below and in Table 1, for adsorbate species ‘a’, . Conversely, the mass transport limited growth regime (also

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

• find the diffusion limited peak at −1.2 V, this means at a slightly lower (less negative) potential than for the macroelectrode. This small shift to lower (less negative) potentials is also observed for the additional plateau at around −0.67 V in the CV of Au and can explained by the altered mass

• transport between a macroscopic rod-shaped electrode and the recessed electrode geometry. For the Ag electrolyte, we find a reduction peak at −0.68 V and a further current increase at higher (more negative) potential. Both, might be related to the deposition of ions and additional ions, originating from

Simulation tool for assessing the release and environmental distribution of nanomaterials

• Haoyang Haven Liu,
• Muhammad Bilal,
• Anastasiya Lazareva,
• Arturo Keller and
• Yoram Cohen

Beilstein J. Nanotechnol. 2015, 6, 938–951, doi:10.3762/bjnano.6.97

• chemical pollutants (e.g., Mend-Tox [13][14], CalTOX [15], TRIM.FaTE [16]), these are not directly applicable for ENMs. Unlike gaseous and dissolved chemical pollutants, for which interphase mass transport rates are governed by chemical potential (fugacity) driving forces that are constrained by

• scenario library). The results can then be visualized via a series of graphical representations. The dynamic multimedia ENM distributions can be represented as: (a) ENM temporal concentration (or mass) profiles in various compartments (Figure 8), (b) intermedia mass transport rates or fluxes, (c) ENM mass

Electron-stimulated purification of platinum nanostructures grown via focused electron beam induced deposition

• Brett B. Lewis,
• Michael G. Stanford,
• Jason D. Fowlkes,
• Kevin Lester,
• Harald Plank and
• Philip D. Rack

Beilstein J. Nanotechnol. 2015, 6, 907–918, doi:10.3762/bjnano.6.94

• down to room temperature. This is consistent with our proposed mass-transport limited regime where the O2 residence time increases the available O2 on the surface (and ultimately diffused to the PtCx matrix) so subsequent electron stimulated reactions and COx removal can proceed. While the initial

Synthesis of Pt nanoparticles and their burrowing into Si due to synergistic effects of ion beam energy losses

• Pravin Kumar,
• Udai Bhan Singh,
• Kedar Mal,
• Sunil Ojha,
• Indra Sulania,
• Dinakar Kanjilal,
• Dinesh Singh and
• Vidya Nand Singh

Beilstein J. Nanotechnol. 2014, 5, 1864–1872, doi:10.3762/bjnano.5.197

• coupling. The melting of materials along the ion trajectory generates a surface tension gradient due to an imbalance of the surface and the interface energies, which further gives rise to mass transport through capillary action. The migration of metallic atoms and subsequent agglomeration can result in the

Formation of Cu_xAu_1−x phases by cold homogenization of Au/Cu nanocrystalline thin films

• Alona Tynkova,
• Gabor L. Katona,
• Gabor A. Langer,
• Sergey I. Sidorenko,
• Svetlana M. Voloshko and
• Dezso L. Beke

Beilstein J. Nanotechnol. 2014, 5, 1491–1500, doi:10.3762/bjnano.5.162

• questions about the contributions of a fast mass transport along different grain boundaries (GBs, i.e., short circuits) can be mentioned; they can have an important effect on the entire intermixing process in nanocrystalline bi- or multilayers. In addition the GB diffusion coefficients can cover a range of

• layer (Figure 1b) as well as of the Au composition inside the Cu layer (Figure 1d). In addition there is a minimum of the Cu profile inside the Au layer. These are the consequences of the GB mass transport along the GBs. The complete filling-up of grain boundaries, e.g., in Au would lead to a maximum

Volcano plots in hydrogen electrocatalysis – uses and abuses

• Paola Quaino,
• Fernanda Juarez,
• Elizabeth Santos and
• Wolfgang Schmickler

Beilstein J. Nanotechnol. 2014, 5, 846–854, doi:10.3762/bjnano.5.96

• measure. In recent years, it has been claimed that the old values for Pt, Ir, Pd, as used by Trasatti [5] or Nørskov et al. [7], are too low because of mass transport limitations [21][22]. The new values correspond to the upper points in the error bars for these metals in Figure 2, while the lower points

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

• mm thickness, inner diameter 12 mm, exposed electrode area ca. 1 cm2, roughness factor ca. 5) to obtain a thin layer of electrolyte which can be effectively exchanged and allows a well defined mass transport from the inlet capillary positioned in the center of the cell body to six surrounding outlet

Shape-selected nanocrystals for in situ spectro-electrochemistry studies on structurally well defined surfaces under controlled electrolyte transport: A combined in situ ATR-FTIR/online DEMS investigation of CO electrooxidation on Pt

• Sylvain Brimaud,
• Zenonas Jusys and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2014, 5, 735–746, doi:10.3762/bjnano.5.86

• spectro-electrocatalytic studies on structurally well defined electrodes under enforced and controlled electrolyte mass transport will be demonstrated, using Pt nanocrystals prepared by colloidal synthesis procedures and a flow cell set-up allowing simultaneous measurements of the Faradaic current, FTIR

• possible to perform in situ spectroscopy (infrared reflection–absorption spectroscopy, IR-RAS) on single crystal surfaces, but the thin electrolyte layer precludes any significant mass transport [4][5][6]. On the other hand, mass transport of the electro-active species can be enforced and properly

• measurements, IR spectroscopic detection of adsorbed species such as reaction intermediates or reaction side-products, and mass spectrometric detection of volatile reaction (side) products at the same time [15][20]. For spectro-electrochemical studies of reactions sensitive to mass transport effects, which

Atomic layer deposition, a unique method for the preparation of energy conversion devices

• Julien Bachmann

Beilstein J. Nanotechnol. 2014, 5, 245–248, doi:10.3762/bjnano.5.26

• ’: each reaction deposits an amount of material defined by the availability of surface reactive groups, not by the (local) partial pressure of gaseous precursors. This growth mode circumvents mass transport as the rate-limiting factor of the increase of the film thickness, thereby allowing for a

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

• oxidation of formic acid on Pd/Ni electrocatalysts with the increase of Pd mass. Note that it can also be because of the mass transport effect [43] since diffusion into such narrow channels can differ strongly from standard 2D models. Conclusion In this study, well-defined Pd/Ni nanocatalysts grown by ALD

• thickness and size of Pd particles, but also because of the electronic effects between the alloyed Pd/Ni metals or because of the mass transport effect in 3D nanostructures. This explains the trend of higher peak current densities for the electrooxidation of formic acid at a lower Pd content in the Pd/Ni

Design criteria for stable Pt/C fuel cell catalysts

• Josef C. Meier,
• Carolina Galeano,
• Ioannis Katsounaros,
• Jonathon Witte,
• Hans J. Bongard,
• Angel A. Topalov,
• Claudio Baldizzone,
• Stefano Mezzavilla,
• Ferdi Schüth and
• Karl J. J. Mayrhofer

Beilstein J. Nanotechnol. 2014, 5, 44–67, doi:10.3762/bjnano.5.5

• above catalyst degradation pathways, in mass transport limitations for the reactants [54]. It is also assumed that the formation of excessive oxygenated functional groups at the carbon surface can increase the hydrophilicity of the support and thus enhance flooding effects that can hamper the transport

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

• current is controlled by mass transport at any applied potential [49][50][51]. Hence, it has been proposed that the measured current is not resulting from the HPORRs themselves, which are considered to be purely chemical processes, but rather from the following electrochemical Pt-surface regeneration

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

• rate limited regime (RRL)). However, if the dwell-time is large and a small pitch is used, the reactions are limited by the number of available precursor molecules (mass transport limited regime (MTL)). In most cases the complete electron-induced dissociation of a precursor molecule is not a single

Lithium peroxide crystal clusters as a natural growth feature of discharge products in Li–O₂ cells

• Tatiana K. Zakharchenko,
• Anna Y. Kozmenkova,
• Daniil M. Itkis and
• Eugene A. Goodilin

Beilstein J. Nanotechnol. 2013, 4, 758–762, doi:10.3762/bjnano.4.86

• provided. In the particular case of lithium peroxide platelets, they gradually produce submicron crystal clusters with complex morphology. Thus this study indicates that Li2O2 crystal clusters are deposited onto the electrode. This layer, however, remains porous, which allows a further mass transport

Preparation of electrochemically active silicon nanotubes in highly ordered arrays

• Tobias Grünzel,
• Young Joo Lee,
• Karsten Kuepper and
• Julien Bachmann

Beilstein J. Nanotechnol. 2013, 4, 655–664, doi:10.3762/bjnano.4.73

• based on porous silicon [7][9]. However, no study is available to date in which the geometric parameters of this system were varied systematically in order to pinpoint the critical length scales associated with mass transport, charge transport, and mechanical relaxation. We propose an experimental

Ultramicrosensors based on transition metal hexacyanoferrates for scanning electrochemical microscopy

• Maria A. Komkova,
• Angelika Holzinger,
• Andreas Hartmann,
• Alexei R. Khokhlov,
• Christine Kranz,
• Arkady A. Karyakin and
• Oleg G. Voronin

Beilstein J. Nanotechnol. 2013, 4, 649–654, doi:10.3762/bjnano.4.72

• with a size of 25 μm and less. For such electrodes (ultramicroelectrodes, UME) the thickness of the diffusion layer is comparable to the diameter of the electrode resulting in enhanced mass transport in comparison to macroscopic electrodes and thus leading to improved sensitivity and detection limits