TY - JOUR A1 - Rades, Steffi A1 - Hodoroaba, Vasile-Dan A1 - Ortel, Erik A1 - Wirth, Thomas A1 - Borghetti, P. A1 - Garcia, S. A1 - Gómez, E. A1 - Blanco, M. A1 - Alberto, Gabriele A1 - Martra, G. T1 - Organic surface modification and analysis of titania nanoparticles for self-assembly in multiple layers N2 - Parameters of TiO2 coatings can greatly influence their final performance in largescale applications such as photocatalytic measurements, orthopedic and/or dental prostheses, cell cultures, and dye-sensitized solar cells. From different film deposition procedures, self-assembly of TiO2 NPs in multiple layers was selected for systematic characterization. EDX, AES and ToF-SIMS analysis have been carried out in order to evaluate the functionalization of several types of TiO2 NPs differing in size, shape and surface area. KW - TiO2 KW - Nanoparticles KW - Surface modification KW - Functionalization PY - 2017 UR - https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/organic-surface-modification-and-analysis-of-titania-nanoparticles-for-selfassembly-in-multiple-layers/66776A4CA7FD059CE39041A99A922D90 DO - https://doi.org/10.1017/S1431927617010029 SN - 1431-9276 SN - 1435-8115 VL - 23 IS - S1 (July) SP - 1872 EP - 1873 PB - Cambridge University Press CY - New York, NY, U.S.A. AN - OPUS4-42457 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rades, Steffi T1 - Automated feature analysis of nanoparticles by high-resolution transmission scanning electron microscopy and energy dispersive X-ray spectroscopy T2 - EuroNanoForum (ENF) 2015 CY - Riga, Lativa DA - 2015-06-09 PY - 2015 AN - OPUS4-33487 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rades, Steffi T1 - Analysis of functionalization of TiO2 nanoparticles and various substrates by means of SEM-EDX, AES and ToF-SIMS N2 - The physico-chemical characteristics of TiO2 coatings can greatly influence their final performance. In SETNanoMetro, different deposition procedures are being set for applying films of TiO2 NPs with defined and homogenous thickness on supports of interest for the applications studied in the project. The selected substrates are the following: (i) Silica glasses for photocatalytic measurements, (ii) Ti-alloys for orthopedic and/or dental prostheses, and for cell cultures, and (iii) Conductive glasses (e.g. Fluorine doped Tin Oxide, FTO) for dye-sensitized solar cells. From the different film deposition procedures studied within the project Self-assembly of TiO2 NPs in multiple layers was selected. For this, surface modification of the substrate and of TiO2 nanoparticles (NPs) with e.g. silane coupling agents is a prerequisite. First attempts to prepare the self-assembled coating on the functionalized glass substrates seem to indicate that the functionalized NPs adhere to the substrates, even if the final coatings were not homogenous and presented agglomerates. ToF-SIMS results support this outcome. In order to use the layer-by-layer deposition technique for the formation of TiO2 films by controlled self-assembly of the TiO2 NPs, the proper complementary moieties for the functionalization of the NPs were chosen. A first set of NPs has been produced by reaction with (3-aminopropyl)phosphonic acid (APPA) in order to functionalize the surface with free amino-groups. Then, the complementary NP set can be obtained from an aliquot of the first one, through the conversion of free surface amino-groups to aldehydes by reaction with glutaraldehyde. A proper approach for the functionalization of two types of TiO2, commercial P25 (Evonik) and SETNanoMetro-sample labelled UT001, with APPA was developed. A second set of NPs consisting of three types of TiO2 NPs, P25 and SETNanoMetro NPs (TiO2 NPs with high specific surface area > 150 m2/g and TiO2 NPs with low size < 20 nm) was functionalized with (3-aminopropyl)triethoxysilane (APTS). As for the previous set of NPs, the complementary NP set was obtained through the conversion of free surface amino-groups to aldehydes by reaction with glutaraldehyde. EDX, AES and ToF-SIMS spectra were collected and analyzed to demonstrate the presence of the surface functionalization of the different types of TiO2 NPs. T2 - Nanoscience meets Metrology - Synthesis, Characterization, Testing and Applications of Validated Nanoparticles - International Summer School CY - Turin, Italy DA - 04.09.2016 KW - Time-of-flight secondary-ion mass spectrometry KW - X-ray spectroscopy KW - Auger electron spectroscopy KW - Electron microscopy KW - Nanoparticles KW - Thin films PY - 2016 UR - http://www.setnanometro.eu/events/ AN - OPUS4-38064 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sötebier, Carina A1 - Bierkandt, Frank A1 - Rades, Steffi A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Weidner, Steffen T1 - Sample loss in asymmetric flow field-flow fractionation coupled to inductively coupled plasma-mass spectrometry of silver nanoparticles N2 - In this work, sample losses of silver nanoparticles (Ag NPs) in asymmetrical flow field-flow fractionation (AF4) have been systematically investigated with the main focus on instrumental conditions like focusing and cross-flow parameters as well as sample concentration and buffer composition. Special attention was drawn to the AF4 membrane. For monitoring possible silver depositions on the membrane, imaging laser ablation coupled to inductively coupled plasma mass spectrometry (LA-ICP-MS) was used. Our results show that the sample residue on the membrane was below 0.6% of the total injected amount and therefore could be almost completely avoided at low sample concentrations and optimized conditions. By investigation of the AF4 flows using inductively coupled plasma mass spectrometry (ICP-MS), we found the recovery rate in the detector flow under optimized conditions to be nearly 90%, while the cross-flow, slot-outlet flow and purge flow showed negligible amounts of under 0.5%. The analysis of an aqueous ionic Ag standard solution resulted in recovery rates of over 6% and the ionic Ag content in the sample was found to be nearly 8%. Therefore, we were able to indicate the ionic Ag content as the most important source of sample loss in this study. KW - Asymmetric flow filed-flow fractionation KW - ICP-MS KW - Nanoparticles KW - Sample loss KW - Quantification PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-336171 DO - https://doi.org/10.1039/c5ja00297d SN - 0267-9477 SN - 1364-5544 VL - 30 IS - 10 SP - 2214 EP - 2222 PB - Royal Society of Chemistry CY - London AN - OPUS4-33617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -