TY - RPRT A1 - Bartczack, Dorota A1 - Taché, Olivier A1 - Hodoroaba, Vasile-Dan T1 - Report on the homogeneity assessment of bimodal gold materials (nPSize1 and nPSize2) and particle number concentration by frequency method T2 - Community EMPIR Project 17NRM04 nPSize (Improved traceability chain of nanoparticle size measurements) N2 - The main objective was to assess homogeneity of two bimodal gold materials, namely nPsize1 and nPSize2, containing approximately 1:1 and 10:1 particle number-based ratio of ~30nm and ~60nm particles. Particle number-based concentration within the two size fractions was determined with spICP-MS using the particle frequency method of calibration. KW - Nanoparticles KW - Homogeneity KW - Particle number concentration KW - Gold KW - nPSize PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595451 DO - https://doi.org/10.5281/zenodo.10654245 SP - 1 EP - 5 PB - Zenodo CY - Geneva AN - OPUS4-59545 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Bartczak, D. A1 - Hodoroaba, Vasile-Dan T1 - Report on the development and validation of the reference material candidates with non-spherical shape, non-monodisperse size distributions and accurate nanoparticle concentrations T2 - Community EMPIR Project 17NRM04 nPSize (Improved traceability chain of nanoparticle size measurements) N2 - One aim of the EMPIR nPSize project 17NRM04 was to develop and validate three classes of candidate reference (test) materials (RTMs), with i) well-defined non-spherical shape, ii) relatively high polydispersity index, and iii) accurate particle concentrations. To fulfil the requirements of the project, 11 different types of materials were prepared. Following the initial assessment of the materials suitability, nPSize5_PT_UNITO, nPSize6_AC_UNITO and nPSize7_GN_CEA materials were found unsuitable for the project, due to various reasons. PT material was deemed unsuitable due to its predominantly agglomerated nature. AC material contained relatively high amount of impurities (other particle forms). GN material was found too heterogeneous in both the length and width for the purpose of the project. The remaining 8 candidate RTMs were assessed for their homogeneity and stability and used for successful delivery of the associated activities within the nPSize project. KW - Nanoparticles KW - Particle size distribution KW - Reference materials KW - Non-spherical shape KW - EMPIR nPSize KW - Electron microscopy KW - AFM KW - SAXS PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-556015 DO - https://doi.org/10.5281/zenodo.7016466 SP - 1 EP - 22 PB - Zenodo CY - Geneva AN - OPUS4-55601 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bennet, Francesca A1 - Burr, L. A1 - Schmid, D. A1 - Hodoroaba, Vasile-Dan T1 - Towards a method for quantitative evaluation of nanoparticles in suspension via Microprinting and SEM analysis N2 - A series of different nanoparticle suspensions (Gold, Latex, and SiO2 in varying concentrations) were microprinted onto TEM grids in a 4 x 4 array in the concentration range 7x10^8 to 1x10^11 NP/mL and imaged with SEM and TSEM. Concentrations and printing conditions (temperature, relative humidity) were varied in order to minimize the coffee ring effect. T2 - nanoSAFE 2020 CY - Online meeting DA - 16.11.2020 KW - Nanoparticles KW - Microprinting KW - Image analysis PY - 2020 AN - OPUS4-51699 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bennet, Francesca A1 - Burr, L. A1 - Schmid, D. A1 - Hodoroaba, Vasile-Dan T1 - Towards a method for quantitative evaluation of nanoparticle from suspensions via microarray printing and SEM analysis JF - Journal of Physics: Conference Series N2 - As part of the development of a library of accurate and efficient methods for measurement of nanoparticle properties, we develop and optimize a method for the efficient analysis of nanoparticle size distribution from suspensions via microprinting and digital analysis of electron microscopy (SEM and TEM) images, with the ultimate aim of automated quantitative concentration analysis (calculated from drop volume). A series of different nanoparticle suspensions (gold, latex, and SiO2 in varying sizes and concentrations) were printed onto TEM grids in a 4 x 4 array in the concentration range 7x10^8 to 1x10^11 nanoparticles/mL and imaged with SEM. Concentrations and printing conditions (temperature, relative humidity) were varied in order to minimize the coffee-ring effect. KW - Nanoparticles KW - Particle size distribution KW - Electron microscopy KW - Microarray printing KW - Sample preparation KW - Nanoparticle concentration PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528455 DO - https://doi.org/10.1088/1742-6596/1953/1/012002 VL - 1953 SP - 012002 PB - IOP Publishing AN - OPUS4-52845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Harald T1 - Core-shell systems - different cases N2 - Coating, stabilization layers, functionalization of particles or simple contamination are common variants of a core-shell system. For smaller nanoparticles this is of major importance. A particle with 16 nm diameter and a usual surface layer of 2 nm will have the same volume for the core as for the shell. In this case the material of the particle doesn’t have a clear definition. It is a common case that a particle consists of four different layers: Core, shell, stabilization layer and contamination. The properties of the particles differ according to this structure. For example silver particles might have a different dissolution rate for pure particles and for particles which are grown on top of a core. Different solubility or defined other properties of materials is a common reason for producing core-shell systems. Gold cores are surrounded by silica to stabilize them or to get a defined distance between the cores. Silica might be surrounded by gold and the silica dissolved afterwards. This delivers hollow shells. Another important example for core-shell systems are quantum dots. A small core is surrounded by a different material for increasing the photoluminescence. Furthermore there a stabilization layer is needed. The smallest part of the final particles is the initial core. The photoluminescence is based on this core, but the shells contain much more material. Categorization should address this. Core-shell systems are not covered by most of the existing decision trees for grouping. They are either regarded as special case or a singular layer. This disqualifies core-shell systems for grouping within the common models. There might be a very easy way to avoid this problem and even to combine some of the different decision trees. Starting the decision tree with the solubility of the outer shell and subsequently addressing the inner layers will be a pragmatic approach to solve the problem. If there is no shell, the categorization can start with a tiered approach or with the proposed “stawman” chemical categorization. If a shell is covering the surface there is a need to check if the shell is stable. If it is stable, the particle can be categorized based on this shell. If it is soluble, the ions need to be addressed as in the classic case. Furthermore the shell might increase the uptake by the cells. If the ions and the uptake are not critical the categorization can continue with the next layer. With this not perfect but pragmatic approach, the surface layers can be addressed with very limited additional efforts. Most criteria are based on classically tabulated data. Including a rating system like the precautionary matrix approach might even address the fact that some parameters are not always Yes/No, e.g. solubility, ion toxicity and uptake. T2 - OECD Expert Meeting on Grouping and Read Across for the Hazard Assessment of Manufactured Nanomaterials CY - Brussels, Belgium DA - 13.04.2016 KW - OECD KW - Nanoparticles KW - Nanomaterials KW - Grouping KW - Nano PY - 2016 AN - OPUS4-35774 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chambers, Aaron T1 - Synthesis of functionalized ZIF nanoparticles for effective composite formation N2 - A presentation looking at ZIF-8 nanoparticles and functionalising them for more effective ZIF composite formation. T2 - UoB/BAM mini conference CY - Birmingham, UK DA - 06.10.2022 KW - MOF composite KW - 2PP KW - ZIF-8 KW - Nanoparticles PY - 2022 AN - OPUS4-56482 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chambers, Aaron A1 - Smales, Glen A1 - Pauw, Brian Richard A1 - Yeung, Hamish T1 - Using an automation assisted Synthesis to produce functionalized ZIF-8 nanoparticles for effective composite formation N2 - This presentation details the progress of the PhD project so far. It discuss the background of the project such as what is a MOF, ZIF and ZIF composite before discussing the aims and approaches for the work. Then the presentation looks at the data obtained so far and the techniques/syntheses used. T2 - Postgraduate Researcher Symposium, University of Birmingham CY - Online meeting DA - 27.06.2023 KW - Automation KW - Nanoparticles KW - ZIF-8 KW - Composites PY - 2023 AN - OPUS4-57867 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chambers, Aaron T1 - Synthesis of ZIF nanoparticles with functionalisation towards effective composite formation N2 - A presentation on functionalising ZIF-8 nanoparticles for composite formation. Characterisation data for the nanoparticles is shown. T2 - Materials Chemistry Seminar CY - Online meeting DA - 23.02.23 KW - MOF composite KW - Nanoparticles KW - ZIF-8 PY - 2023 AN - OPUS4-57210 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cios, Grzegorz A1 - Hodoroaba, Vasile-Dan A1 - Tokarski, T. A1 - Bala, P. T1 - High throughput nanoparticle analysis using transmission Kikuchi diffraction N2 - In the present paper we show an approach of measuring large numbers of nanoparticles in a single scan TKD. TiO2 anatase nanoparticles (NP) of bipyramidal shape were deposited on standard carbon grid used for TEM. The procedure used promoted formation of NP ‘monolayer’ islands with uniform distribution of NPs on the carbon surface which allowed mapping of large number of nanoparticles in the single island. Collection of whole map covering ~2800 nanoparticles took nearly 20 minutes. Inverse pole figure color coded map indicates that the NPs are either lying on a {101} facet (within 10° range around perfect {101} parallel to the carbon surface orientation) on the carbon film or are lying on a {100} facet (within 10° range around the perfect {100} parallel to the carbon surface orientation). Very unlikely was the NP orientation standing on a {001} face. The NPs size distribution described as equivalent circle diameter (ECD) has been also evaluated and the mean NP ECD was 59 nm with standard deviation of 15 nm, i.e. in good agreement with electron microscopy or AFM results. This study shows high potential of the technique for crystalline NPs analysis with respect to geometrical orientation of the particles on the substrate. With known orientation, the 3D dimensional characterisation of such non-spherical NPs becomes possible from 2D projection electron micrographs. Moreover, the NP size distribution can be easily extracted. Superior accuracies down to 1-2 nm are achievable. The approach is applicable also on thin lamellae extracted from particulate (or mesoporous) layers. T2 - EMAS 2023 - 17th European Workshop on Modern Developmennts and Applications in Microbeam Analysis CY - Krakow, Poland DA - 07.05.2023 KW - Nanoparticles KW - TKD KW - Electron microscopy KW - TiO2 KW - Orientation PY - 2023 UR - https://www.microbeamanalysis.eu/events/event/60-emas-2023-17th-european-workshop-on-modern-developments-and-applications-in-microbeam-analysis AN - OPUS4-57519 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Darvishi Kamachali, Reza T1 - Melting upon Coalescence of Solid Nanoparticles JF - Solids N2 - The large surface-to-volume ratio of nanoparticles is understood to be the source of many interesting phenomena. The melting temperature of nanoparticles is shown to dramatically reduce compared to bulk material. Yet, at temperatures below this reduced melting point, a liquid-like atomic arrangement on the surface of nanoparticles is still anticipated to influence its properties. To understand such surface effects, here, we study the coalescence of Au nanoparticles of various sizes using molecular dynamics simulations. Analysis of the potential energy and Lindemann index distribution across the nanoparticles reveals that high-energy, high-mobility surface atoms can enable the coalescence of nanoparticles at temperatures much lower than their corresponding melting point. The smaller the nanoparticles, the larger the difference between their melting and coalescence temperatures. For small enough particles and/or elevated enough temperatures, we found that the coalescence leads to a melting transition of the two nominally solid nanoparticles, here discussed in relation to the heat released due to the surface reduction upon the coalescence and the size dependence of latent heat. Such discontinuous melting transitions can lead to abrupt changes in the properties of nanoparticles, important for their applications at intermediate temperatures. KW - Nanoparticles KW - Molecular Dynamics KW - Surface-induced Melting PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552183 DO - https://doi.org/10.3390/solids3020025 VL - 3 IS - 2 SP - 361 EP - 373 PB - MDPI AN - OPUS4-55218 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Friedrich, C. M. A1 - Weigel, S. A1 - Marvin, H. A1 - Rauscher, H. A1 - Wohlleben, W. A1 - Babick, F. A1 - Löschner, K. A1 - Mech, A. A1 - Brüngel, R. A1 - Hodoroaba, Vasile-Dan A1 - Gilliland, D. A1 - Rasmussen, K. A1 - Ghanem, A. T1 - The NanoDefine Methods Manual N2 - This document is a collection of three JRC Technical Reports that together form the “NanoDefine Methods Manual”, which has been developed within the NanoDefine project ‘Development of an integrated approach based on validated and standardized methods to support the implementation of the EC recommendation for a definition of nanomaterial’, funded by the European Union’s 7th Framework Programme, under grant agreement 604347. The overall goal of the NanoDefine project was to support the implementation of the European Commission Recommendation on the definition of nanomaterial (2011/696/EU). The project has developed an integrated empirical approach, which allows identifying a material as a nano- or not a nanomaterial according to the EC Recommendation. The NanoDefine Methods Manual consists of three parts: Part 1: The NanoDefiner Framework and Tools, which covers the NanoDefiner framework, general information on measurement methods and performance criteria, and tools developed by NanoDefine such as a materials categorisation system, a decision support flow scheme and an e-tool. Part 2: Evaluation of Methods, which discusses the outcome of the evaluation of the nanomaterials characterisation methods for measuring size. Part 3: Standard Operating Procedures (SOPs), which presents the 23 Standard Operating Procedures developed within the NanoDefine project. In this combined document, these three parts are included as stand-alone reports, each having its own abstract, table of contents, page, table and figure numbering, and references. KW - Nanomaterial KW - Particle size distribution KW - Nanoparticles KW - NanoDefine KW - Nanomaterial classification PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504250 SN - 978-92-76-12335-4 DO - https://doi.org/10.2760/79490 VL - JRC117501 SP - 1 EP - 451 PB - Publications Office of the European Union CY - Luxembourg AN - OPUS4-50425 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grauel, Bettina A1 - Würth, Christian A1 - Resch-Genger, Ute A1 - Haase, M. A1 - Homann, C. T1 - Progress report NaYF4:Yb,Er upconversion nanoparticles: determination of energy loss processes for the systematic enhancement of the luminescence efficiency N2 - A report on the progress of the PhD work on upconversion nanoparticles is given, showing lifetimes and quantum yields of single- and co-doped Yb,Er nanocrystals with and without inert shell. T2 - Arbeitsgruppenseminar Prof. Oliver Benson CY - Berlin, Germany DA - 23.10.2019 KW - Upconversion KW - Spectroscopy KW - Nanoparticles KW - Lifetime PY - 2019 AN - OPUS4-49754 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hahn, Marc Benjamin T1 - TOPAS cell model with nanoparticles N2 - These files contain cell models for TOPAS/Geant4 and the inclusion of nano particles in particle scattering simulations. A simple spherical cell with nanoparticles can be generated in a fast manner. The user has the option to include the following organelles: nucleus, mitochondria, cell membrane. Additionally nanoparticles can be included in the cytosol and at the surface of the nucleus and/or the mitochondria. The C++ classes in this repository extend the functionality of the TOPAS (http://www.topasmc.org/) Monte-Carlo program, which is itself a wrapper of the Geant4 MCS Toolkit (http://geant4.org). The sourcecode together with examples and scorers are provided. "If you use this extension please cite the following literature: Hahn, M.B., Zutta Villate, J.M. "Combined cell and nanoparticle models for TOPAS to study radiation dose enhancement in cell organelles." Sci Rep 11, 6721 (2021). https://doi.org/10.1038/s41598-021-85964-2 " KW - Monte-Carlo simulation KW - MCS KW - Geant4 KW - TOPAS KW - TOPAS-nBio KW - Dosimetry KW - Nanoparticles KW - Nanoparticle KW - AuNP KW - Gold KW - Microdosimetry KW - Targeted nanoparticle KW - Simulation KW - Particle scattering KW - Cell KW - Nucleus KW - Mitochondria KW - Cancer therapy KW - Radiation therapy PY - 2020 UR - https://github.com/BAMresearch/TOPAS-CellModels UR - https://github.com/MarcBHahn/TOPAS-CellModels DO - https://doi.org/10.26272/opus4-51150 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-51150 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heilmann, Maria A1 - Bienert, Ralf A1 - Prinz, Carsten A1 - Emmerling, Franziska T1 - Synthesis of bimetallic nickel nanoparticles as catalysts for the Sabatier reaction N2 - Nanoparticles (NP) have become important materials for a variety of chemical technologies. The enhanced surface-area-to-volume ratio of NPs, making them excellent for use as catalyst, in analytical assays, and for antimicrobial applications. Nickel NPs have exhibited immense potential as important catalyst for the Sabatier reaction, i.e. converting waste to energy via transformation of CO2 into CH4, and could replace the rare earth elements such as Ru, PT, or Rh. In this work we describe the solvothermal synthesis of monometallic and bimetallic nickel nanoparticles. Monodisperse monometallic Ni NPs were synthesized using Oleylamin as solvent and reducing agent. The nanoparticles were investigated using small angle scattering (SAXS), scanning transmission electron microscopy (STEM) and energy dispersive X-ray spectroscopy (EDX), showing that the NPs are stable while the surface is not entirely covered. However, Ni has a high propensity to undergo oxidation, and becoming deactivated by coke formation. Hence, we further explore the preparation of bimetallic NPs, where a second metal is added to stabilize the Ni. Bimetallic Cu-Ni NPs were synthesized by simultaneous solvothermal reduction. These bimetallic NPs exhibit excellent catalytic properties are promising candidates to be used as catalysts for efficient energy storage. T2 - 31. Tag der Chemie 2019 CY - Berlin, Germany DA - 11.07.2019 KW - Nanoparticles KW - Catalysis KW - Synthesis PY - 2019 AN - OPUS4-50171 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heilmann, Maria A1 - Bienert, Ralf A1 - Prinz, Carsten A1 - Emmerling, Franziska T1 - Synthesis of bimetallic nickel nanoparticles for catalysis N2 - We present the synthesis of monodisperse monometallic Ni nanoparticles (NPs) and bimetallic NiCu respectively NiCo NPs. The NPs were investigated using SAXS, STEM, EDX, and XANES, showing that the NPs are size tunable and stable while the surface is not entirely covered. Nickel NPs have exhibited immense potential as important catalyst for the Sabatier reaction, i.e. converting waste to energy via transformation of CO2 into CH4. T2 - 11th Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 04.12.2019 KW - Nanoparticles KW - Catalysis KW - Synthesis PY - 2019 AN - OPUS4-50172 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heilmann, Maria A1 - Bienert, Ralf A1 - Prinz, Carsten A1 - Emmerling, Franziska T1 - Synthesis of bimetallic nickel nanoparticles as catalysts for the Sabatier reaction N2 - Nanoparticles (NPs) have become important materials for a variety of chemical technologies. The enhanced surface-area-to-volume ratio of NPs, making them excellent for use as catalyst, in analytical assays, and for antimicrobial applications. Nickel NPs have exhibited immense potential as important catalyst for the Sabatier reaction, i.e. converting waste to energy via transformation of CO2 into CH4, and could replace the rare earth elements such as Ru, PT, or Rh. In this work we describe the solvothermal synthesis of monometallic and bimetallic nickel nanoparticles. Monodisperse monometallic Ni NPs were synthesized using Oleylamin as solvent and reducing agent. The nanoparticles were investigated using small angle scattering (SAXS), scanning transmission electron microscopy (STEM) and energy dispersive X-ray spectroscopy (EDX), showing that the NPs are stable while the surface is not entirely covered. However, Ni has a high propensity to undergo oxidation, and becoming deactivated by coke formation. Hence, we further explore the preparation of bimetallic NPs, where a second metal is added to stabilize the Ni. Bimetallic Cu-Ni NPs were synthesized by simultaneous solvothermal reduction. These bimetallic NPs exhibit excellent catalytic properties are promising candidates to be used as catalysts for efficient energy storage. T2 - Adlershofer Forschungsforum 2019 CY - Berlin, Germany DA - 11.11.2019 KW - Nanoparticles KW - Catalysis KW - Synthesis PY - 2019 AN - OPUS4-50173 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heilmann, Maria A1 - Kulla, Hannes A1 - Prinz, Carsten A1 - Bienert, Ralf A1 - Marquardt, Julien A1 - de Oliveira Guilherme Buzanich, Ana A1 - Emmerling, Franziska T1 - Synthesis of Bimetallic Nickel Nanoparticles as Catalysts for the Sabatier Reaction N2 - Nanoparticles (NP) have become important materials for a variety of chemical technologies. The enhance surface-area-to-volume ratio of NPs is very high, making them excellent for use as catalyst, in analytical assays, and for antimicrobial applications. Nickel NPs have exhibited immense potential as important catalyst for the Sabatier reaction, i.e. converting waste to energy via transformation of CO2 into CH4, and could replace the rare earth elements such as Ru, PT, or Rh. In this work we describe the solvothermal synthesis of monometallic and bimetallic nickel nanoparticles. Monodisperse monometallic Ni nanoparticles were synthesized using Oleylamin as solvent and reducing agent. The nanoparticles were investigated using small angle scattering (SAXS), scanning transmission electron microscopy (STEM) and energy dispersive X-ray spectroscopy (EDX), showing that the catalytically active sites are accessible. However, Ni has a high propensity to undergo oxidation, and becoming deactivated by coke formation. Hence, we further explore the preparation of bimetallic NPs, where a second metal is added to stabilize the Ni. Bimetallic Cu-Ni NPs were synthesized by simultaneous solvothermal reduction. These bimetallic NPs exhibit excellent catalytic properties are promising candidates to be used as catalysts for efficient energy storage. T2 - Joint Polish-German Crystallographic Meeting CY - Wroclaw, Poland DA - 24.02.2020 KW - Nanoparticles KW - Synthesis KW - Catalysis PY - 2020 AN - OPUS4-51663 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heilmann, Maria A1 - Prinz, Carsten A1 - Bienert, Ralf A1 - Wendt, Robert A1 - Kunkel, Benny A1 - Radnik, Jörg A1 - Hoell, Armin A1 - Wohlrab, Sebastian A1 - de Oliveira Guilherme Buzanich, Ana A1 - Emmerling, Franziska T1 - Size-Tunable Ni-Cu Core-Shell Nanoparticles: Structure, Composition, and Catalytic Activity N2 - Nanoparticles (NPs) have become important materials for a variety of chemical technologies, including catalysis. One of the main challenges is the reduction of green house gases, such as CO2. One opportunity besides the capturing is the conversion to synthesis gas via the reverse water-gas shift reaction. A facile and efficient method is described for the solvothermal synthesis of size-tunable, stable, and uniform NiCu core-shell NPs. The diameter of the NPs can be tuned in a range from 6 nm to 30 nm and the Ni:Cu ratio from 30:1 to 1:1. The NPs are structurally characterized with combination of transmission electron microscopy, anomalous small-angle X-ray scattering, X-ray photoelectron spectroscopy, and X-ray absorption fine structure. Using these analytical methods, a core-shell-shell structure their chemical composition is elucidated. A depletion from the core to the shell is observed, with the core consisting of NiCu alloy, surrounded by an inner Ni-rich shell and an outer NiO shell. The SiO2-supported NiCu core-shell NPs show pronounced selectivity of >99% for CO in the catalytic reduction of CO2 to CO using hydrogen as reactant (reverse water–gas shift reaction). T2 - Nanoalloys: recent developments and future perspectives Faraday Discussion CY - London, UK DA - 21.09.2022 KW - Nanoparticles KW - Core-shell KW - Catalysis PY - 2022 AN - OPUS4-56831 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heilmann, Maria A1 - Hodoroaba, Vasile-Dan T1 - Project 15 Measurement of particle size and shape distribution of bipyramidal titania including deposition from liquid suspension N2 - The progress in the VAMAS Project #15" Measurement of particle size and shape distribution of bipyramidal titania including deposition from liquid suspension" within TWA 34 Nanoparticle Populations is presented with highlight of the following points: - Determine and compare particle size and shape distribution by means of: • electron microscopy (SEM, TEM, STEM-in-SEM) • atomic force microscopy (AFM) • small angle X-ray scattering (SAXS) - Determine uncertainty induced by deposition protocol from liquid suspension with comparison to known values from a prior ILC with already deposited nanoparticles on TEM grids. - Provide comparative validation of protocols for the techniques other than TEM. T2 - VAMAS Regional Workshop 2023 CY - Online meeting DA - 24.01.2023 KW - Nanoparticles KW - VAMAS KW - Electron microscopy KW - AFM KW - SAXS KW - TiO2 PY - 2023 UR - https://www.bam.de/Content/EN/Events/2023/2023-01-24-vamas-regional-workshop.html AN - OPUS4-57220 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heilmann, Maria A1 - Hodoroaba, Vasile-Dan T1 - Project 16 Measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension N2 - The progress of the VAMAS Project 16 "Measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension" in TWA 34 Nanoparticle Populations is presented. Follwowing points are discusssed: - Validate the performance of imaging methods to measure the relative number concentration • electron microscopy (SEM, TEM) and atomic force microscopy (AFM) • two modes of bimodal (30 and 60 nm) silica nanoparticles - Validate the performance of small angle X-ray scattering (SAXS) for the traceable measurement of the number concentration of the two modes. T2 - VAMAS Regional Workshop 2023 - What can pre-normative research do for industry? CY - Online meeting DA - 24.01.2023 KW - Nanoparticles KW - VAMAS KW - Inter-laboratory comparison KW - SiO2 KW - Electron microscopy KW - AFM PY - 2023 UR - https://www.bam.de/Content/EN/Events/2023/2023-01-24-vamas-regional-workshop.html AN - OPUS4-57221 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -