TY - INPR A1 - Corrao, Elena A1 - Gouasmi, Meriem A1 - Sordello, Fabrizio A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Joerg A1 - Maurino, Valter A1 - Pellegrino, Francesco T1 - Tailoring TiO2 Morphology and Surface Chemistry for Optimized Photocatalytic Activity in rGO Hybrids N2 - TiO2–reduced graphene oxide (rGO) hybrids were investigated in this study to elucidate how TiO2 morphology and surface chemistry govern charge-transfer pathways and, ultimately, reaction selectivity. Three anatase TiO2 nanostructures were compared: bipyramids predominantly exposing {101} facets (bipy) and two nanosheet-like samples enriched in {001} facets, either fluorinated (n-sh) or thermally defluorinated and {101}-enriched (n-sh_873K). A constant rGO loading (2 wt.%) was introduced via in situ hydrazine reduction of graphene oxide in the presence of TiO2. Photocatalytic activity was evaluated under Xe-lamp irradiation in two model reactions probing oxidative and reductive pathways: phenol degradation and H2 evolution using formic acid as a scavenger. rGO systematically enhanced phenol degradation for all morphologies, with bipy+rGO showing the highest activity. In contrast, H2 evolution was consistently suppressed upon rGO incorporation across all TiO2 samples, although the bipyramidal morphology remained the most active within each series. These results highlight that facet exposure and surface functionalization dictate the beneficial or detrimental role of rGO depending on the targeted photocatalytic pathway. KW - Photocatalytic activity KW - Reduced graphene oxide KW - TiO2 KW - Surface chemistry KW - 2D materials PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653476 DO - https://doi.org/10.26434/chemrxiv-2026-65917 SP - 1 EP - 12 PB - American Chemical Society (ACS) AN - OPUS4-65347 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schusterbauer, Robert A1 - Mrkwitschka, Paul A1 - Sahre, Mario A1 - Corrao, Elena A1 - Zurutuza, Amaia A1 - Doolin, Alexander A1 - Pellegrino, Francesco A1 - Radnik, Jörg A1 - Donskyi, Ievgen S. A1 - Hodoroaba, Vasile-Dan T1 - Correlative Chemical Imaging to Reveal the Nature of Different Commercial Graphene Materials N2 - Proper physicochemical characterization of advanced materials and complex industrial composites remains a significant challenge, particularly for nanomaterials, whose nanoscale dimensions and mostly complex chemistry challenge the analysis. In this work, we employed a correlative analytical approach that integrates atomic force microscopy (AFM), scanning electron microscopy (SEM) coupled with energy‐dispersive X‐ray spectroscopy (EDS), time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS), Auger electron spectroscopy (AES), and Raman spectroscopy. This combination enables detailed chemical and structural characterization with sub‐micrometer spatial resolution. Three commercial graphene‐based materials of varying complexity were selected and investigated to test the analytical performance of this approach. Furthermore, one of the commercial graphene oxide samples was chemically functionalized via amination and fluorination. This allowed us to assess how surface modifications influence both the material properties and the limits of the applied analytical techniques. KW - Analytical methods KW - Commercial products KW - Correlative analysis KW - Graphene KW - Surface imaging PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654765 DO - https://doi.org/10.1002/smtd.202502344 SN - 2366-9608 SP - 1 EP - 10 PB - Wiley VHC-Verlag AN - OPUS4-65476 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hickel, Tilmann A1 - Waske, Anja A1 - Tehranchi, Ali A1 - Bhattacharya, Biswajit A1 - Stawski, Tomasz M. A1 - Fellinger, Tim-Patrick A1 - Mehmood, Asad A1 - Witt, Julia A1 - Ozcan, Ozlem A1 - Guilherme Buzanich, Ana A1 - Kumar, Sourabh A1 - Mishra, Rajesh Kumar A1 - Holzer, Marco A1 - Stucchi de Camargo, Andrea Simone A1 - Agudo Jácome, Leonardo A1 - Manzoni, Anna A1 - Fantin, Andrea A1 - John, Elisabeth A1 - Hodoroaba, Vasile-Dan A1 - Bührig, Sophia A1 - Murugan, Jegatheesan A1 - Marschall, Niklas A1 - George, Janine A1 - Darvishi Kamachali, Reza A1 - Maaß, Robert A1 - Emmerling, Franziska T1 - Chemically complex materials enable sustainable high-performance materials N2 - Chemically complex materials (CCMats) 􀀀 including high-entropy alloys, oxides, and related multi-principal element systems 􀀀 offer a paradigm shift in materials design by leveraging chemical diversity to simultaneously optimize functional, structural, and sustainability criteria. The vastness of the compositional and structural space in CCMats propels the field into an expanding exploratory state. To reconcile functional and structural performance across this immense parameter space remains an open challenge. This Perspective evaluates the opportunities and challenges associated with harnessing chemical complexity across a broad spectrum of applications, such as hydrogen storage, ionic conductors, catalysis, magnetics, dielectrics, semiconductors, optical materials, and multifunctional structural systems. It is delineated how three central design strategies: targeted substitution (SUB), defect engineering (DEF), and diversity management (DIV) enable the reconciliation of high functional performance with long-term structural stability and environmental responsibility. Advances in computational thermodynamics, microstructure simulations, machine learning, and multimodal characterization are accelerating the exploration and optimization of CCMats, while robust data infrastructures and automated synthesis workflows are emerging as essential tools for navigating their complex compositional space. By fostering cross-disciplinary knowledge transfer and embracing data-driven design, CCMats are poised to deliver next-generation materials solutions that address urgent technological, energy, and environmental demands. KW - Chemically complex materials KW - Structural stability KW - Functional performance KW - Design strategies KW - Sustainability PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655598 UR - https://www.sciencedirect.com/science/article/pii/S1359028626000033?via%3Dihub DO - https://doi.org/10.1016/j.cossms.2026.101256 SN - 1359-0286 VL - 42 SP - 1 EP - 26 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-65559 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rossi, Andrea A1 - Corrao, Elena A1 - Alladio, Eugenio A1 - Drobne, Damjana A1 - Hodoroaba, Vasile-Dan A1 - Jurkschat, Kerstin A1 - Kononenko, Veno A1 - Madbouly, Loay Akmal A1 - Mrkwitschka, Paul A1 - Yasamin, Nakhli A1 - Novak, Sara A1 - Radnik, Jörg A1 - Saje, Špela A1 - Santalucia, Rosangela A1 - Sordello, Fabrizio A1 - Pellegrino, Francesco T1 - Multivariate optimization and characterization of graphene oxide via design of experiments and chemometric analysis N2 - Controlling the structure and properties of graphene oxide (GO) remains a challenge due to the poor reproducibility of conventional synthetic protocols and limited understanding of parameter-property relationships. In this study, we present an integrated analytical framework that combines Design of Experiments (DoE) with chemometric modelling to systematically assess the effects of eight synthesis variables on GO’s physicochemical and functional features. A Plackett–Burman experimental design enabled efficient screening of synthesis conditions, while comprehensive characterization (spanning UV–Vis spectroscopy, XPS, SEM–EDX, TEM–EDX, and XRD) was coupled with multivariate tools (Principal Component Analysis and Multiple Linear Regression) to identify statistically significant correlations between synthetic inputs and material responses. Notably, we demonstrate that UV–Vis spectra can serve as a robust proxy for oxidation state, offering a rapid and accessible alternative to surface-sensitive methods. The approach yields a predictive analytical toolkit for guiding GO synthesis and highlights a generalizable strategy for the rational design of flat nanomaterials. This work supports reproducible, resource-efficient material development aligned with Safe and Sustainable by Design (SSbD) principles. KW - Graphene oxide KW - 2D-materials KW - Design of Experiment KW - Synthesis KW - Chemometric analysis PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652576 DO - https://doi.org/10.1016/j.flatc.2025.100988 SN - 2452-2627 VL - 55 SP - 1 EP - 9 PB - Elsevier B.V. AN - OPUS4-65257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fernandez-Poulussen, D. A1 - Hodoroaba, Vasile-Dan T1 - Holistic, reliable and practical Characterization Framework for Graphene Family Materials, a correlated approach including Imaging based techniques N2 - ACCORDs is an Horizon Europe project working in the development of an imaging-based characterization framework (ACCORDs framework) for the holistic correlative assessment of Graphene Family Materials (GFMs) as a representative of 2D nanomaterials (NMs) to assess and predict 2D NMs health and environmental risks. The ACCORDs framework will operationalise safe and sustainable by design (SSbD) strategies proposed in past or ongoing H2020 projects or within OECD by correlating low-, medium-, and high-resolution physico-chemical-biological imaging-based methods with non-imaging methods in a tiered approach. ACCORDs will deliver the ACCORDs framework and user guidance, new imaging-based characterisation methods, reference in vitro tests, new reference 2D NMs for different matrices, a new minimum information reporting guideline for FAIR data sharing and reuse of images as well as an atlas with reference images for diagnostics of compromised safety of GFMs/GFM products. The new guidelines and standard proposals will be submitted to standardisation bodies to allow creation of regulatory ready products. The novelty of ACCORDs is in translating the principles of medical imaging-based diagnostics to 2D material hazard diagnostics. ACCORDs will accelerate industrial sectors in the area of aviation, marine construction, drone production, flexible electronics, photovoltaics, photocatalytics and print inks-based sensors. The value ACCORDs proposes to the graphene industry are practical, easy, imaging-based tools for GFM quality monitoring next to the production line with a possibility to be correlated with advanced highresolution imaging characterization methods in case hazard i.e. deviation from controls (benchmark values) are diagnosed. The ACCORDs framework and tools will contribute to the European Green Deal by addressing the topic: “Graphene: Europe in the lead” and to a new European strategy on standardization, released on 2nd February, 2022 T2 - Joint Regulatory Risk Assessors Summit – Advancing Safety & Sustainability Assessments of Advanced Materials CY - Paris, France DA - 19.06.2025 KW - Graphene-related 2D materials (GR2M) KW - Imaging KW - SSbD KW - ACCORDs PY - 2025 UR - https://macrame-project.eu/macrame-meetings-workshops/jointrras/#Agenda AN - OPUS4-63660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fagan, J. A1 - Hodoroaba, Vasile-Dan T1 - VAMAS TWA 34 Nanoparticle Populations Combined Projects P15 and P16 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) and 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. Further, the VAMAS/TWA 34 Project #16 "Measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension" is presented. Follwowing points are discusssed: - Validate the performance of imaging methods to measure the relative number concentration by electron microscopy (SEM, TEM) and atomic force microscopy (AFM) and 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. - Discussion of sample preparation issues - Publication of the results in 2026 T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 50th Steering Committee Meeting CY - London, United Kingdom DA - 14.09.2025 KW - VAMAS KW - Interlaboratory comparison KW - Particle size and shape distribution KW - Particle number concentration KW - Standardisation PY - 2025 UR - https://www.vamas.org/twa34/index.html AN - OPUS4-64234 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - VAMAS Regional Report Advanced Materials Germany 2025 N2 - Regional standardisation activities and how VAMAS can help in any way to promote activities are reported. Activities related to organisational updates, government initiatives/priorities (especially related to Advanced Materials), details of any strategy documents publicly available, networks within Germany and how we engage are presented. T2 - Versailles Project on Advanced Materials and Standards (VAMAS) 50th Steering Committee Meeting CY - London, United Kingdom DA - 14.09.2025 KW - VAMAS KW - Interlaboratory comparison KW - Advanced materials KW - Standardisation PY - 2025 AN - OPUS4-64232 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Madbouly, Loay Akmal A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - Raman Spectroscopy and X-ray Photoelectron Spectroscopy of Commercial Functionalized Graphene N2 - Graphene has found widespread commercial use, particularly in flexible electronics and coatings for substrates such as paper and textiles, in the form of suspensions and inks (Zhang et al., 2017). Functionalization of graphene allows fine-tuning of properties like electrical conductivity. Structural and chemical features of graphene materials are typically analyzed by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). While Raman spectroscopy plays a critical role in identifying the presence of graphene and characterizing its structural defects (Pollard et al., 2017), XPS examines the chemistry of graphene. This study investigates three types of graphene materials — graphene (unfunctionalized, G-graphene), fluorine-functionalized graphene (F-graphene), and nitrogen-functionalized graphene (N-graphene) — across three physical forms: powders, suspensions, and embedded in inks. Functionalization was performed via plasma treatment of G-graphene with fluorine or ammonia gases. Suspensions were obtained by dispersing powders in distilled water, while inks were formulated using diacetone alcohol, carbon black, and graphene. Raman spectroscopy analysis confirmed the graphitic nature of all materials and revealed differences in defect density across different forms. The characteristic D, G, and D’ bands varied in relative intensity, offering insight into structural integrity and functionalization effects. XPS measurements examined core-level spectra (C 1s, F 1s, N 1s), revealing chemical bonding environments and hybridization states, including the sp² and sp³ states. A notable decline in fluorine content in F-graphene suspensions and inks, relative to powders, was observed. Existence of organic fluorine and total absence of metallic fluorine were observed. Raman spectroscopy and XPS data provided a correlated view of structural and chemical evolution through the graphene production chain. T2 - Joint Regulatory Risk Assessors Summit – Advancing Safety & Sustainability Assessments of Advanced Materials CY - Paris, France DA - 19.06.2025 KW - Graphene-related 2D materials (GR2M) KW - Inks KW - Raman Spectroscopy KW - XPS KW - Functionalized graphene PY - 2025 UR - https://macrame-project.eu/macrame-meetings-workshops/jointrras/#Agenda AN - OPUS4-63661 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Habibimarkani, Heydar A1 - Prinz, Carsten A1 - Sahre, Mario A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - CV, TEM, XRD and XPS/HAXPES datasets of FeNi-based nanoparticles for the oxygen evolution reaction N2 - The datasets from Cyclic Voltammetry, Transmision Electron Microscopy, X-ray Diffraction, and (Hard Energy) X-ray Photoelectron Spectroscopy are related to the publication H. Habibimarkani, S.-L. Abram, A. Guilherme Buzanich, C. Prinz, M. Sahre, V.-D. Hodoroaba and J. Radnik "In-depth analysis of FeNi-based nanoparticles for the oxygen evolution reaction" Scientific Reports (2025), https://doi.org/10.1038/s41598-025-92720-3 Details of the materials and the experimental procedures are described in this publications. KW - Oxygen evolution reaction KW - Fe-Ni nanopartices KW - Comprehensive analysis PY - 2025 DO - https://doi.org/10.5281/zenodo.14975964 PB - Zenodo CY - Geneva AN - OPUS4-63335 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Rieck, Arielle A1 - Low, Jian Liang A1 - Dietzmann, Simon A1 - Radnik, Jörg A1 - Teimouri, Zahra A1 - Higgins, Drew A1 - Hodoroaba, Vasile-Dan A1 - Mehmood, Asad A1 - Fellinger, Tim-Patrick T1 - Understanding the Activity Trade-Off between Tetrapyrrolic Fe-NCs and Co-NCs in the Alkaline Oxygen Reduction Reaction N2 - A water-free ionothermal synthesis of porous magnesium-imprinted nitrogen-doped carbon (Mg–NC) materials is introduced to prepare a platform material to investigate electrocatalytic structure-performance relations. Atomically dispersed Co- and Fe-NCs isomorphic to the pristine Mg-NCs are prepared by ion-exchange reactions. The current Mg-templating strategy enables relatively high pyrolysis product yields of up to 50 wt% and resultant Fe-NC and Co-NC catalysts contain high and comparable active metal loading of up to 2.52 wt% Fe and 2.29 wt% Co, respectively. A combination of X-ray spectroscopies with DFT studies reveals a tetrapyrrolic structure of the coordination sites, originating from a pyrolytic magnesium template ion reaction within the ionothermal synthesis. Two sets of highly active isomorphic tetrapyrrolic Fe-NCs and Co-NCs are utilized to understand the differences in intrinsic electrocatalytic performance of Co-NCs and Fe-NCs towards the alkaline oxygen reduction reaction (ORR). Despite their superior valence electronic properties to facilitate the initial outer-sphere electron transfer to O2, Co-NCs show significantly lower performance than Fe-NC with comparable loading. Although the generally discussed weaker binding of peroxide intermediates to CoN4 sites compared to FeN4 sites is evident, experimental and theoretical investigation reveal that it is the underlying peroxide oxidation activity that suppresses the oxygen reduction activity of M-NCs. The high peroxide oxidation activity of Co-NCs explains their reduced alkaline ORR relative to Fe-NCs, shedding light on the understated significance of controlling peroxide chemistry for the optimizing cathodic performance. KW - Magnesium Imprinting KW - Tetrapyrrolic Sites KW - Metal- and nitrogen-doped carbon (M-N-C) KW - Oxygen Reduction Reaction (ORR) KW - Nitrogen doped Carbon PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-651487 DO - https://doi.org/10.26434/chemrxiv-2025-s59s5 SP - 1 EP - 24 AN - OPUS4-65148 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -