TY - CONF A1 - Radnik, Jörg T1 - How to perform reliable xps-measurements? N2 - Reliable measurements are a great challenge in X-ray photoelectron spectroscopy. It will be shown, how to check the performance and calibration of the instrument, the charge compensation, quantification, fitting, and depth profiling. T2 - Course for PhD students at SFB 1073 CY - Göttingen, Germany DA - 23.02.2024 KW - X-ray photoelectron spectroscopy KW - Reproducibility crisis KW - Reliability PY - 2024 AN - OPUS4-59590 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Kim, K. J. A1 - Yu, H. A1 - Lee, S. M. A1 - Kwon, J. H. A1 - Ruh, H. A1 - Radnik, Jörg A1 - Archanjo, B. S. A1 - Annese, E. A1 - Damasceno, J. C. A1 - Achete, C. A. A1 - Yao, Y. A1 - Ren, L. A1 - Gao, H. A1 - Windover, D. A1 - Matsuzaki, H. A1 - Azuma, Y. A1 - Zhang, L. A1 - Fujimoto, T. A1 - Jordaan, W. A. A1 - Reed, B. A1 - Shard, A. G. A1 - Cibik, L. A1 - Gollwitzer, C. A1 - Krumrey, M. T1 - Final report of CCQM-K157 for the measurement of the amount of substance of HfO2 expressed as the thickness of nm films N2 - The key comparison CCQM-K157 for the thickness measurement of HfO2 films was performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The aim of CCQM-K157 is to establish the measurement traceability and to ensure the equivalency in the measurement capability of national metrology institutes for the thickness measurement of HfO2 films. In this key comparison, the thicknesses of six HfO2 films with the nominal thickness range from 0.7 nm to 6 nm were compared by x-ray photoelectron spectroscopy (XPS), x-ray reflectometry (XRR), transmission electron microscopy (TEM), spectroscopic ellipsometry (SE) and medium energy ion scattering spectrometry (MEIS). To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA). KW - CCQM KW - Thin Films KW - HfO2 KW - thickness KW - XPS PY - 2023 DO - https://doi.org/10.1088/0026-1394/60/1A/08010 VL - 60 SP - 08010 PB - IOP AN - OPUS4-63049 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Jungnickel, H. A1 - Tentschert, J. A1 - Luch, A. A1 - Sogne, V. A1 - Maier, F. A1 - Burr, L. A1 - Schmid, D. A1 - Yoon, T.-H. A1 - Petters, R. A1 - Briffa, S.M. A1 - Valsami-Jones, E. T1 - Automation and Standardization—A Coupled Approach Towards Reproducible Sample Preparation Protocols for Nanomaterial Analysis N2 - Whereas the characterization of nanomaterials using different analytical techniques is often highly automated and standardized, the sample preparation that precedes it causes a bottleneck in nanomaterial analysis as it is performed manually. Usually, this pretreatment depends on the skills and experience of the analysts. Furthermore, adequate reporting of the sample preparation is often missing. In this overview, some solutions for techniques widely used in nano-analytics to overcome this problem are discussed. Two examples of sample preparation optimization by au-tomation are presented, which demonstrate that this approach is leading to increased analytical confidence. Our first example is motivated by the need to exclude human bias and focuses on the development of automation in sample introduction. To this end, a robotic system has been de-veloped, which can prepare stable and homogeneous nanomaterial suspensions amenable to a variety of well-established analytical methods, such as dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), field-flow fractionation (FFF) or single-particle inductively coupled mass spectrometry (sp-ICP-MS). Our second example addresses biological samples, such as cells exposed to nanomaterials, which are still challenging for reliable analysis. An air–liquid interface has been developed for the exposure of biological samples to nanomaterial-containing aerosols. The system exposes transmission electron microscopy (TEM) grids under reproducible conditions, whilst also allowing characterization of aerosol composition with mass spectrometry. Such an approach enables correlative measurements combining biological with physicochemical analysis. These case studies demonstrate that standardization and automation of sample preparation setups, combined with appropriate measurement processes and data reduction are crucial steps towards more reliable and reproducible data. KW - Sample preparation KW - Automation KW - Nanomaterial analysis KW - Standardization PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543988 DO - https://doi.org/10.3390/molecules27030985 VL - 27 IS - 3 SP - 1 EP - 22 PB - MDPI AN - OPUS4-54398 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Singh, Chandan A1 - Riedel, Soraya A1 - Konthur, Zoltán A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg A1 - Schenk, J. A. A1 - Schneider, Rudolf T1 - Functionalized Ti3C2Tx nanosheets based biosensor for point-of-care detection of SARS-CoV‑2 antigen N2 - MXenes are considered a promising class of two-dimensional materials with extraordinary physical and electrochemical properties. Distinguished features like high specific surface area and outstanding electrical conductivity make them suitable for electrochemical biosensing applications. Here, we report the development of a biosensor involving the functionalized MXene−titanium carbide nanosheets (Ti3C2Tx-NS) and monoclonal antibodies against the SARS-CoV-2 nucleocapsid protein (anti-SARS-CoV-2 mAb) to design a point-of-care device for detection of the SARS-CoV-2 nucleocapsid protein (SARS-CoV-2 NP) antigen. Few-layered titanium carbide nanosheets (denoted as FL-Ti3C2Tx-NS) have been synthesized using a single-step etching and delamination method and characterized using optical and electron microscopy techniques revealing the suitability for immunosensing applications. Binding studies revealed the excellent affinity between the biosensor and the SARS-CoV-2 NP. Electrochemical detection of SARS-CoV-2 NP is performed using differential pulse voltammetry and read by a smartphone-based user interface. The proposed FL-Ti3C2Tx-NS based biosensor offers the detection of SARS-CoV-2 NP with a limit of detection of 0.91 nM in a wide detection range in spiked saliva samples. Additionally, there is no cross-reactivity in the presence of potential interferants like SARS-CoV-2 spike glycoprotein and bovine serum albumin. These findings demonstrate the potential of MXenes in developing a rapid and reliable tool for SARS-CoV-2 NP detection. While we report the biosensing of SARS-CoV-2 NP, our system also paves the way for the detection of other SARS-CoV-2 antigens like spike protein or other biomolecules based on antigen−antibody interactions. KW - Antigen testing KW - Few-layered titanium carbide nanosheets KW - SARS-CoV-2 nucleocapsid protein KW - Label-free detection KW - Electrochemical immunosensor PY - 2023 DO - https://doi.org/10.1021/acsaenm.2c00118 SN - 2771-9545 N1 - Geburtsname von Riedel, Soraya: Höfs, S. - Birth name of Riedel, Soraya: Höfs, S. VL - 1 IS - 1 SP - 495 EP - 507 PB - American Chemical Society CY - Washington, DC AN - OPUS4-56931 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Saleh, Maysoon I. A1 - Rühle, Bastian A1 - Wang, Shu A1 - Radnik, Jörg A1 - You, Yi A1 - Resch-Genger, Ute T1 - Assessing the protective effects of different surface coatings on NaYF4:YB3+, Er3+, upconverting nanoparticles in buffer and DMEM N2 - We studied the dissolution behavior of β NaYF4:Yb(20%), Er(2%) UCNP of two different sizes in biologically relevant media i.e., water (neutral pH), phosphate buffered saline (PBS), and Dulbecco’s modified Eagle medium (DMEM) at different temperatures and particle concentrations. Special emphasis was dedicated to assess the influence of different surface functionalizations, particularly the potential of mesoporous and microporous silica shells of different thicknesses for UCNP stabilization and protection. Dissolution was quantified electrochemically using a fluoride ion selective electrode (ISE) and by inductively coupled plasma optical emission spectrometry (ICP OES). In addition, dissolution was monitored fluorometrically. These experiments revealed that a thick microporous silica shell drastically decreased dissolution. Our results also underline the critical influence of the chemical composition of the aqueous environment on UCNP dissolution. In DMEM, we observed the formation of a layer of adsorbed molecules on the UCNP surface that protected the UCNP from dissolution and enhanced their fluorescence. Examination of this layer by X ray photoelectron spectroscopy (XPS) and mass spectrometry (MS) suggested that mainly phenylalanine, lysine, and glucose are adsorbed from DMEM. These findings should be considered in the future for cellular toxicity studies with UCNP and other nanoparticles and the design of new biocompatible surface coatings. KW - Fluorescence KW - Lifetime KW - Method KW - Quantification KW - Stability KW - Coating KW - Surface chemistry KW - Lanthanide KW - Fluoride KW - Electrochemistry KW - ICP-OES KW - Upconversion KW - Nano KW - Particle KW - Aging KW - Quality assurance KW - Mass spectrometry KW - XPS PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-515984 DO - https://doi.org/10.1038/s41598-020-76116-z SN - 2045-2322 VL - 10 IS - 1 SP - 19318-1 EP - 19318-11 PB - Springer Nature CY - London AN - OPUS4-51598 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Reliable analysis of the elemental composition of graphene oxide flakes with energy dispersive spectroscopy (SEM/EDS) and x-ray photoelectron spectroscopy (XPS) N2 - Suspensions of graphene-related 2D materials (GR2M) are broadly used for further applications like printable electronics. The reliable quantification of the composition of graphene-related 2D materials as liquid suspensions is still a challenging task, which can hinder the commercialisation of the products. Specific parameters to be measured are defined, e.g. the oxygen-to-carbon (O/C) concentration ratio, the trace metal impurities, or the functional groups present [1], but reference protocols are still missing. One of the central methods for the quantification is X-ray photoelectron spectroscopy (XPS) as a rather expensive method. Therefore, the development of cheaper alternatives is highly desired. One attractive alternative of XPS is energy-dispersive spectroscopy (EDS) which is usually coupled with scanning electron microscopy (SEM). This combination is one of the most widely used methods in analytical laboratories. In this contribution the results of a systematic study on the capability of SEM/EDS to reliably quantify the O/C ratio in a well-defined and well-characterized graphene oxide material [2] are presented. The robustness of the SEM/EDS results obtained at various measurement conditions (various excitation energies) is tested by comparing the results to the established XPS analysis [3], which has been carried out on the same samples. It is demonstrated that for samples prepared by drop-casting on a substrate, both surface-sensitive XPS analysis and bulk-characterising EDS result in very similar elemental composition of oxygen and carbon for thick spots. Further, the effect of untight deposited material enabling co-analysis of the (silicon) substrate, is evaluated for both methods, XPS and EDS. The last results clearly show the influence of the substrate on the analysis of the results and stressed out the importance of the sample preparation. T2 - E-MRS Spring Meeting CY - Strasbourg, France DA - 26.05.2025 KW - Graphene oxide KW - Reliable Analysis KW - Ionic Liquid KW - Reference Material PY - 2025 AN - OPUS4-63336 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chemello, Giovanni A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan T1 - Analysis of Industrial Graphene-Based Flakes – First Results on Morphological Characterization, Sample Preparation and Chemical Composition N2 - In order to bridge the gap between lab-scale and industrial-scale production of graphene it is necessary to develop processes, equipment and measurement procedures to control the material features. One of the crucial reasons of graphene’s limited commercialization is the lack of standard procedures to properly characterize and define the material chemical and structural properties down to the nanometer level. This leads to many issues regarding material synthesis repeatability, inappropriateness choice of measurands and measurement reproducibility which heavily affect the consistency of the material performance. In our study, a comparative analysis is performed on two different series (G5 and G6) of industrial graphene powders, each series produced with four types of functionalization: raw graphene, oxygen-functionalized, nitrogen-functionalized and fluorine-functionalized. All the 8 sample variants were analyzed from a chemical and morphological point of view in the form of powders prepared as slightly pressed in metallic sample holders. The results of the comparative chemical analyses XPS and EDS show a good agreement in the concentration values for all the elements present in the samples, despite the different analysis volumes addressed by the two techniques. For this reason, the samples can be considered homogeneous in both lateral and vertical direction. A clear influence of the morphology on the composition is evident. Therefore, such correlative measurements of morphology and composition are necessary for a comprehensive characterization of industrial graphene flakes. KW - Graphene powder KW - XPS KW - HAXPES KW - SEM KW - EDS KW - Functionalized graphene PY - 2022 DO - https://doi.org/10.1017/S1431927622004342 SN - 1435-8115 VL - 28 IS - Suppl 1 SP - 1006 EP - 1008 PB - Cambridge University Press CY - New York, NY AN - OPUS4-55512 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - XPS of GR2M N2 - The activities of ISO-G-Scope are presented. The influence of the sample preparation and the results of XPS/HAXPES measurements are discussed. T2 - Graphene Workshop @ ISO TC 229 Meeting CY - Teddington, UK DA - 16.11.2022 KW - Graphene related materials KW - X-ray photoelectron spectroscopy KW - Sample preparation KW - Hard X-ray photoelectron spectroscopy PY - 2022 AN - OPUS4-56434 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - Knowledge Infrastructure supporting image-based characterisation of 2D graphene materials N2 - To better understand the relationship between image features and biological effects such as toxicity,we have developed a method combining image thresholding and pixel-wise segmentation to create annotated datasets. These datasets are used to train machine learning models and establish human–AI learning loops for material classification and structure detection. We employ deep learning architectures such as ResNet, EfficientNet, and U-Net to automate the classification and segmentation of SEM/TEM images of 2D nanomaterials, with targeted manual annotation focusing on key structures (graphene flakes, agglomerates, contaminants, etc.). This approach ensures reproducible, large-scale analysis, which is essential for studying the links between structure and biological response. Finally, our methodology aligns with OECD requirements and contributes to the Safe and Sustainable by Design (SSbD) framework, aiming to enhance product reliability and sustainability. T2 - Joint Regulatory Risk Assessors Summit – Advancing Safety & Sustainability Assessments of Advanced Materials CY - Paris, France DA - 19.06.2025 KW - Graphene KW - 2D materials KW - Knowledge infrastructure KW - Imaging KW - Machine learning PY - 2025 UR - https://macrame-project.eu/macrame-meetings-workshops/jointrras/#Agenda AN - OPUS4-63682 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - How to measure the chemical composition of industrial graphene - New insights from an interlaboratory comparison N2 - International standards describing reliable protocols will facilitate the commercialization of graphene and related 2D materials. One physico-chemical key property next to flake size and thickness is the chemical composition of the material. Therefore, an ISO standard is under development with X-ray photoelectron spectroscopy having a prominent role. With its information depth of around 10 nm which is the similar length scale as the thickness as of particles of 2D materials consisting of a few monolayer XPS seems to be highly suitable for this purpose. Different sample preparation methods like pressing the powders onto adhesive tapes, into recesses, or into solid pellets result in inconsistencies in the quantification. For the validation of the quantification with XPS an interlaboratory comparison was initiated under the auspice of the “Versailles Project on Advanced Materials and Standards” (VAMAS). First results confirm that the sample preparation method (pellet vs. powder) influences the quantification results clearly. T2 - Characterization of Nanomaterials Colloquium CY - Berlin, Germany DA - 04.07.2023 KW - X-ray photoelectron spectroscopy KW - Functionalized graphene KW - Interlaboratory comparison PY - 2023 AN - OPUS4-57897 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - In depth analysis of commercial functionalized graphene nanoplateles towards structure-activity relationships N2 - The analysis of commercial graphene related products from the raw material to inks is discussed and the input to structure-activity relationships. Different approaches to obtain structure-activity relationships like operando or using data mining are presented. Challenges and recommendation to obtain structure-activity relationships are given. T2 - Joint Regulator Risk Summit: Advancing Safety & Sustainability Assessments of Advanced Materials CY - Paris, France DA - 19.06.2025 KW - Functionalized graphene KW - Structure activity relationsships KW - Commercialisation PY - 2025 AN - OPUS4-63565 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - Surface Analysis and Context of the New HAXPES@BAM N2 - The Competence Centre nano@BAM is presenting a new X-ray Photoelectron Spectrometer – the HAXPES (XPS at hard energy) – for researching advanced materials at the nanoscale. With HAXPES detailed chemical information can now be gained not only from the first outermost nanometres of the sample surface, but also from deeper regions. Top international experts will share their knowledge and key findings on how to utilise HAXPES for exploring the surface of various advanced materials. Following the lectures, we will show you a short demo of the new instrument and answer your questions. T2 - Inauguration of the HAXPES@BAM - A new Hard-X-Ray Photoelectron Spectrometer CY - Online meeting DA - 25.01.2022 KW - XPS KW - HAXPES KW - Nano@BAM KW - Surface Analysis PY - 2022 UR - https://www.bam.de/Content/EN/Events/2022/2022-01-25-hapex.html AN - OPUS4-54377 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rossi, Andrea A1 - Alladio, Eugenio A1 - Drobne, Damjana A1 - Hodoroaba, Vasile-Dan A1 - Jurkschat, Kerstin A1 - Kononenko, Veno A1 - Madbouly, Loay Akmal A1 - Mrkwitschka, Paul A1 - Novak, Sara A1 - Radnik, Jörg A1 - Saje, Špela A1 - Santalucia, Rosangela A1 - Sordello, Fabrizio A1 - Pellegrino, Francesco T1 - Development of a one-pot synthesis of rGO in water by optimizing Tour’s method parameters N2 - Since its first synthesis in 2004, graphene has been widely studied and several different synthesis methods has been developed. Solvent exfoliation of graphite and the reduction of graphene oxide previously obtained through graphite oxidation are the most employed. In this work, we exploited synthesis conditions of a method usually employed for obtaining graphene oxide (the Tour’s method) for directly obtaining a very poorly oxidised material with characteristics like reduced graphene oxide. For the first time, a one-pot synthesis of reduced graphene oxide (rGO) is reported avoiding the use of a post-synthesis chemical or thermal reduction of the graphene oxide that requires further reagents, heat and time. KW - Graphene KW - 2D-materials KW - Tour's method KW - rGO KW - One-pot synthesis PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611827 DO - https://doi.org/10.1038/s41598-024-73606-2 SN - 2045-2322 VL - 14 SP - 1 EP - 10 PB - Springer Nature CY - London AN - OPUS4-61182 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chemello, Giovanni A1 - Despotelis, Konstantinos A1 - Paton, Keith A1 - Clifford, Charles A A1 - Pollard, Andrew A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan T1 - Approaches for the measurement of lateral dimensions of graphene oxide flakes using scanning electron microscopy N2 - There is a practical need, especially from the industrial community, to accurately measure the size and shape of graphene oxide (GO) flakes of commercial origin, in a reliable, simple, and unambiguous way. The sample preparation is a decisive step to obtain a homogeneous distribution of flakes on a substrate, which is suitable for image analysis. A certain level of inhomogeneity was still found but could be accepted for the purpose of this lateral size measurement study. A measurement procedure for Scanning Electron Microscopy (SEM) including sample preparation, measurement, image analysis and reporting was developed and validated to be applied for the lateral size analysis of “real-world” 2D flakes. Samples were produced for analysis by drop casting GO dispersions onto Si/SiO2 substrates. After SEM imaging, the images were analysed using two approaches to derive size and shape parameters. The influence of different operators has been evaluated. A maximum difference of 10% for the size descriptor and 2% for shape descriptor was found for both image analysis approaches when different samples of the same source material are measured and analysed by the same operator, hence indicating variability caused by sample preparation and analysing different sample areas. When different laboratories/operators perform the image analysis on exactly the same images and same flakes, the deviation found for the size descriptor is 2% and 4.6% corresponding to the two approaches applied, while no difference in the shape descriptor is observed. KW - Graphene oxide KW - SEM KW - Lateral dimension KW - Standardisation KW - Imaging PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625070 DO - https://doi.org/10.1088/2632-959X/adae28 VL - 6 IS - 1 SP - 1 EP - 11 PB - IOP Publishing AN - OPUS4-62507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - XPS at BAM - Some insights into our activities N2 - Some examples will be given showing the application of XPS in different fields, like polymers, nanoparticles, solar cells and inorganic thin films. T2 - Besuch beim GFZ Potsdam CY - Potsdam, Germany DA - 18.05.2018 KW - XPS KW - Surface analytics KW - Nanoparticles KW - Polymers KW - Solar cells PY - 2018 AN - OPUS4-44981 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Graphene Week - Training Session: Standardisation and Validation N2 - In this training session the standardisation landscape will be presented. Another focus is how science can put into standards. In the second part the validation of protocols will be validated. Reference materials and interlaboratory comparisons as validation tools will be discussed. T2 - Graphene Week 2024 CY - Prague, Czech Republic DA - 14.10.2024 KW - Precision KW - Trueness KW - Accuracy KW - Interlaboratory comparison KW - Certified reference materials PY - 2024 AN - OPUS4-61469 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knigge, Xenia A1 - Guo, Z. A1 - Valsami-Jones, E. A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - Influence of Sterilization on the Surface of Nanoparticles Studied with XPS / HAXPES in Comparison to SEM / EDS N2 - Nanosafety is becoming increasingly important as nanomaterials are widely used in industrial processes and consumer products. For nanotoxicity measurements prior sterilization of the samples is necessary, but as structure activity relationships are made with properties of pristine particles, the question arises, if the sterilization process has an impact on the physico-chemical properties of nanoparticles and thus on the biological behavior. This question will be addressed in this talk. For this purpose, results from SEM and EDS measurements are combined with those of a novel lab-based HAXPES spectrometer in order to obtain a more complete picture. At the end, an influence of sterilization will be evident, which indicates a restructuring of the nanoparticles owing to sterilization. T2 - Microscopy & Microanalysis 2022 CY - Portland, USA DA - 31.07.2022 KW - XPS KW - HAXPES KW - SEM KW - EDS KW - Nanoparticles PY - 2022 DO - https://doi.org/10.1017/S1431927622004287 VL - 28 SP - 986 EP - 988 PB - Cambridge University Press AN - OPUS4-55352 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Photoelectron spectroscopy N2 - A short introduction into the basics of Photoelectron Spectroscopy with the focus on surface sensitivity and applications is presented. T2 - Industrietreffen im Forschungs- und Innovationszentrum (FIZ) der BMW Group CY - Munich, Germany DA - 09.01.2018 KW - XPS KW - ESCA KW - Surface analytics PY - 2018 AN - OPUS4-43737 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - The next steps in the standardisation of graphene-related and other 2D materials (GR2M) N2 - The first products with graphene-related 2D material (GR2M) are on the market. In this phase trust is essential for the commercial success of these products, between the individual partners of the product value chain, and between the manufacturer and the consumer. Standards are an important tool for building this trust. The first steps have been taken in standardisation, e.g. in terminology and the characterization of raw materials. But there are still some challenges to overcome such as bringing the standards to the factory floor and real-world products. For the validation of new protocols and methods there is a need of reference data and materials. But not only the measurement should be reproducible, the whole analytical workflow from sample storage and preparation to data analysis should be reproducible. Another important issue is the establishment of credible structure-activity relationships which allows the prediction of the properties of the GR2M, but also of the biological activity including the safety for the human health and the environment. Such relationships can be used for read-across and grouping and can facilitate the regulation of the advanced materials. In addition, 2D materials beyond graphene should also be considered and can benefit from the experience from the standardisation of graphene and graphene oxide. T2 - Nanomaterials Standardization Strategy Forum - Europe - Republic of Korea CY - Online meeting DA - 08.07.2025 KW - Commercialisation KW - Product-value chain KW - Confidence building PY - 2025 AN - OPUS4-63731 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Reliable chemical characterization of industrial graphene related materials N2 - International standards describing reliable protocols will facilitate the commercialization of graphene and related 2D materials. One physico-chemical key property next to flake size and thickness is the chemical composition of the material. Therefore, an ISO standard is under development with X-ray photoelectron spectroscopy having a prominent role. With its information depth of around 10 nm which is the similar length scale as the thickness as of particles of 2D materials consisting of a few monolayer XPS seems to be highly suitable for this purpose. Different sample preparation methods like pressing the powders onto adhesive tapes, into recesses, or into solid pellets result in inconsistencies in the quantification. For the validation of the quantification with XPS an interlaboratory comparison was initiated under the auspice of the “Versailles Project on Advanced Materials and Standards” (VAMAS). First results confirm that the sample preparation method (pellet vs. powder) influences the quantification results clearly. Considering this effect, a good agreement of the results from the different participants were observed. Similar results were observed for raw, N- and F-functionalized graphene. T2 - Graphene CY - Manchester, England, UK DA - 27.06.2023 KW - X-ray photoelectron spectroscopy KW - Functionalized graphene KW - Interlaboratory comparison KW - VAMAS PY - 2023 AN - OPUS4-57895 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -