Nano
Filtern
Dokumenttyp
- Zeitschriftenartikel (351)
- Vortrag (339)
- Posterpräsentation (102)
- Forschungsdatensatz (53)
- Sonstiges (19)
- Beitrag zu einem Tagungsband (16)
- Buchkapitel (10)
- Beitrag zu einem Sammelband (10)
- Forschungsbericht (9)
- Zeitschriftenheft (Herausgeberschaft für das komplette Heft) (6)
Sprache
- Englisch (880)
- Deutsch (52)
- Spanisch (2)
- Mehrsprachig (1)
Schlagworte
- Nanoparticles (124)
- Nano (70)
- SAXS (64)
- XPS (60)
- Laser-induced periodic surface structures (LIPSS) (59)
- Fluorescence (52)
- Quantum yield (52)
- Nanoparticle (49)
- Electron microscopy (48)
- X-ray scattering (46)
- Quality assurance (42)
- SEM (42)
- Nanomaterial (39)
- Lifetime (36)
- VAMAS (35)
- HAXPES (33)
- Dye (31)
- Particle (30)
- Particle size distribution (30)
- Lanthanide (28)
- Sensor (28)
- Nanomaterials (27)
- Photophysics (27)
- Synthesis (27)
- MOUSE (24)
- Surface functionalization (24)
- Standardisation (23)
- Graphene (22)
- Photoluminescence (22)
- Reference material (22)
- Method (21)
- Simulation (20)
- Small-angle X-ray scattering (20)
- X-ray photoelectron spectroscopy (20)
- AFM (19)
- Interlaboratory comparison (19)
- NIR (19)
- Traceability (19)
- Nanocomposites (18)
- Boehmite (17)
- Quantum dots (17)
- Sample preparation (17)
- Thin films (17)
- Geant4 (16)
- Imaging (16)
- Laser processing (16)
- Luminescence (16)
- NanoSolveIT (16)
- Nanocomposite (16)
- Reference materials (16)
- Upconversion nanoparticle (16)
- Inter-laboratory comparison (15)
- Quantum dot (15)
- Surface chemistry (15)
- Functionalized graphene (14)
- Metrology (14)
- Microdosimetry (14)
- Polymer (14)
- Upconversion (14)
- Applications (13)
- Dosimetry (13)
- Femtosecond laser (13)
- Geant4-DNA (13)
- MCS (13)
- OECD (13)
- Quantitative spectroscopy (13)
- SWIR (13)
- Scattering (13)
- DNA (12)
- EDS (12)
- Ellipsometry (12)
- Optical spectroscopy (12)
- Conductivity (11)
- EBSD (11)
- Energy transfer (11)
- Nanostructures (11)
- Particle size (11)
- Silica (11)
- Size (11)
- Standardization (11)
- Surface analysis (11)
- Brightness (10)
- Broadband dielectric spectroscopy (10)
- Femtosecond laser ablation (10)
- Integrating sphere spectroscopy (10)
- LEE (10)
- Mechanism (10)
- Radiation damage (10)
- Small angle scattering (10)
- TiO2 (10)
- Atomic force microscopy (9)
- AuNP (9)
- Automation (9)
- Epoxy (9)
- Friction (9)
- Gold (9)
- Methodology (9)
- Microstructures (9)
- Monte-Carlo simulation (9)
- Oxygen evolution reaction (9)
- Quantification (9)
- Radioactive decay (9)
- Spectroscopic ellipsometry (9)
- Surface (9)
- ToF-SIMS (9)
- Wear (9)
- Energy deposit (8)
- Ligand (8)
- Nanoconfinement (8)
- Protein (8)
- Rigid amorphous fraction (8)
- Additive manufacturing (7)
- Advanced materials (7)
- Cancer treatment (7)
- Coating (7)
- DNA damage (7)
- Excitation power density (7)
- FIB (7)
- Flash DSC (7)
- Ionic Liquid crystals (7)
- Monte-Carlo simulations (7)
- Nanoplastics (7)
- Nanostructure (7)
- Radiationtherapy (7)
- Reference data (7)
- Shape (7)
- Single particle (7)
- Spectroscopy (7)
- Surface modification (7)
- TEM (7)
- TOPAS (7)
- Titania nanoparticles (7)
- Uncertainty (7)
- Advanced Materials (6)
- Beta decay (6)
- Brachytherapy (6)
- Calibration (6)
- Cell (6)
- Flow cytometry (6)
- G5P (6)
- Glass (6)
- Gold Nanoparticles (6)
- Indium phosphide (6)
- Lab automation (6)
- Laser ablation (6)
- Laser-induced periodic surface structures, LIPSS (6)
- Low energy electrons (6)
- Measurement uncertainty (6)
- NP (6)
- Nano powder (6)
- Nanoplastic (6)
- Particle scattering simulations (6)
- Prüfrichtlinie (6)
- Radiation therapy (6)
- Radiolysis (6)
- Reproducibility (6)
- Small-angle scattering (6)
- TOPAS-nbio (6)
- Temperature (6)
- VSSA (6)
- Adsorbed Layer (5)
- Analysis (5)
- Application (5)
- Assay (5)
- Bacteria (5)
- Biofilm (5)
- Cancer (5)
- Carbon nanotubes (5)
- Characterization (5)
- Core-shell (5)
- Correlative imaging (5)
- Data analysis (5)
- Dynamics (5)
- EPMA (5)
- Ectoine (5)
- Elastomers (5)
- Elemental composition (5)
- Environment (5)
- ISO/TC 202 (5)
- LLG (5)
- Mesoporous iridium oxide films (5)
- Micromagnetism (5)
- Microscopy (5)
- Multiphoton lithography (5)
- Multiplexing (5)
- Nanocrystal (5)
- Nanoparticle concentration (5)
- Nanosafety (5)
- Nanotechnology (5)
- OH radical (5)
- OOMMF (5)
- Optical assay (5)
- Oxidation (5)
- Particle scattering (5)
- Polycarbonate (5)
- Reference product (5)
- Risk assessment (5)
- Rubber (5)
- Semiconductor quantum dot (5)
- Sensing (5)
- SiO2 (5)
- Single-stranded DNA-binding proteins (5)
- Software (5)
- Surfaces (5)
- Topas (5)
- X-ray (5)
- XRD (5)
- nPSize (5)
- 2D materials (4)
- 3D (4)
- Advanced manufacturing (4)
- BDS (4)
- Bacterial adhesion (4)
- Barcoding (4)
- Bead (4)
- Bending modulus (4)
- Bio-SAXS (4)
- Bioimaging (4)
- Calcium sulfate (4)
- Capillary waves (4)
- Catalysis (4)
- Certification (4)
- Clustered nanoparticles (4)
- Conductometry (4)
- Corrosion (4)
- Cosolute (4)
- Crystallization (4)
- DLS (4)
- Data (4)
- Data stewardship (4)
- Diffraction (4)
- Direct laser writing (4)
- EC4SafeNano (4)
- Ectoin (4)
- Encoding (4)
- Epoxy nanocomposites (4)
- Exchange interaction (4)
- Fast Scanning Calorimetry (4)
- Ferromagnetism (4)
- GVP (4)
- Glass transition (4)
- Graphene oxide flakes (4)
- Guideline (4)
- Hard X-ray photoelectron spectroscopy (HAXPES) (4)
- ISO/TC 229 (4)
- Image analysis (4)
- Image segmentation (4)
- InP (4)
- Instrumentation (4)
- Introduction (4)
- Ionic liquid (4)
- Ionizing radiation damage (4)
- Iron oxide (4)
- Iron oxide nanoparticles (4)
- Knowledge Readiness Level (4)
- Landau Lifshitz equation (4)
- Life sciences (4)
- Livermore model (4)
- Magnetic moment (4)
- McSAS3 (4)
- Microbeam Analysis (4)
- Microbeam analysis (4)
- Microstructure (4)
- Modelling (4)
- NEXAFS (4)
- Nano@BAM (4)
- NanoDefine (4)
- Nanoelectronics (4)
- Nanofibers (4)
- Nanomaterial classification (4)
- Nanopartikel (4)
- Non-destructive operando analysis (4)
- Nucleation (4)
- OH radical scavenger (4)
- Object oriented micromagnetic framework (4)
- Orientation (4)
- PDF (4)
- Penelope model (4)
- Polymers (4)
- Probe (4)
- Protein unfolding (4)
- Radiotherapy (4)
- Raman (4)
- Regulation (4)
- Round robin (4)
- Signal enhancement (4)
- Size distribution (4)
- Standard (4)
- Stochastic Landau Lifshitz Gilbert equation (4)
- Strategic Research Agenda (SRA) (4)
- Synchrotron (4)
- TMDSC (4)
- Thickness (4)
- Titanium dioxide (4)
- Transmission electron microscopy (4)
- Two-photon polymerization (4)
- Ultrashort laser processing (4)
- particle scattering (4)
- ssDNA (4)
- AIS (3)
- Aggregation (3)
- Aging (3)
- Analytical sciences (3)
- Antibacterial (3)
- Atomic Force Microscopy (3)
- Automated synthesis (3)
- BAM reference data (3)
- BioSAXS (3)
- Biofilm formation (3)
- Biosensor (3)
- CLS (3)
- Cement (3)
- Ceria (3)
- Contact resonance (3)
- Core-shell nanoparticles (3)
- Correlative analysis (3)
- Cycloalyphatic epoxy oligosiloxane (3)
- Cytotoxicity (3)
- Differential scanning calorimetry (3)
- Electrochemistry (3)
- Electromagnetic scattering (3)
- Electron Microscopy (3)
- Electrospinning (3)
- Energy dispersive X-ray spectroscopy (3)
- European Centre (3)
- European Metrology Network (EMN) (3)
- Extracellular vesicles (EV) (3)
- FTIR (3)
- Femtosecond laser processing (3)
- Framework (3)
- Free electron laser (3)
- General Materials Science (3)
- Gold nanocluster (3)
- Graphene oxide (3)
- Graphene related 2D materials (3)
- Growth Kinetics (3)
- Hard-energy X-ray photoelectron spectroscopy (3)
- Hybrid metrology (3)
- ISO (3)
- ISO/TC 229 Nanotechnologies (3)
- Immunoassay (3)
- Intermodulation AFM (3)
- Interpenetrating polymer network (3)
- Interphase (3)
- LIPSS (3)
- Laboratory automation (3)
- Laboratory management (3)
- Limit of detection (3)
- Linearity (3)
- Lubricants (3)
- MOF (3)
- Machine Learning (3)
- Machine learning (3)
- Magnetic nanoparticles (3)
- Mechanical properties (3)
- Method comparison (3)
- Micro- and nanoplastics (3)
- Microprinting (3)
- Modeling (3)
- Monte Carlo (3)
- NAP-XPS (3)
- NMR (3)
- Nano particle (3)
- Nano-powder (3)
- Nanomaterialien (3)
- Nanopipettes (3)
- Nanostructure quantification (3)
- OH Radical (3)
- OH radicals (3)
- Optical assays (3)
- Particle Synthesis (3)
- Photocatalysis (3)
- Pollutant (3)
- Polyglycerol (3)
- Porosity (3)
- Porous materials (3)
- Procedure (3)
- Processing (3)
- Protein G (3)
- Proteins (3)
- Python (3)
- Quantitative NMR (3)
- ROS (3)
- Radical Scavenger (3)
- Ratiometric sensors (3)
- Resonance frequency (3)
- Rigidity (3)
- SAXS/WAXS (3)
- SEM/EDS (3)
- SOP (3)
- Safe-by-Design (3)
- Scattering pattern analysis (3)
- Semiconductor (3)
- Sensors (3)
- Shell (3)
- Small-angle xray scattering (3)
- Stability (3)
- Standards (3)
- Surface chemical analysis (3)
- Surface group (3)
- Surface group analysis (3)
- Surface group quantification (3)
- Test guideline (3)
- Thin Films (3)
- Ti6Al4V alloy (3)
- Time-resolved scattering (3)
- Topas-MC (3)
- Topas-nBio (3)
- Toxicology (3)
- Transmission Kikuchi Diffraction (TKD) (3)
- Tribology (3)
- Ultrafast laser processing (3)
- Ultrashort laser pulses (3)
- Upconversion nanocrystal (3)
- Upconversion nanoparticles (3)
- Validation (3)
- X-ray Photoelectron Spectroscopy (3)
- beta particle (3)
- nanoparticle (3)
- pH probe (3)
- pH sensing (3)
- 100Cr6 (2)
- 150th anniversary (2)
- 2D Materials (2)
- 2PP (2)
- 3D Fourier Transform (2)
- 3D printing (2)
- ABC (2)
- ACEnano (2)
- APTES (2)
- Absolute fluorescence (2)
- Achsschenkel (2)
- Adsorption (2)
- Advanced Manufacturing (2)
- Advanced nanomaterials (2)
- Affinity chromatography (2)
- Agglomerates (2)
- Aktivkohle (2)
- Aluminium oxide hydroxide (2)
- Amorphous silica particles (2)
- Amplification (2)
- Amyloid (2)
- Anodization (2)
- Antibody (2)
- Antibody coating (2)
- Au (2)
- Automated image analysis (2)
- Automatisation (2)
- BAM (2)
- BET (2)
- Bacterial adhesion tests (2)
- Base damage (2)
- Base loss (2)
- Behavior and Systematics (2)
- Beta particle (2)
- Bio-based concrete (2)
- Bioconjugation (2)
- Biofilm growth (2)
- Bruchmechanische Auslegung (2)
- Bundesanstalt für Materialforschung und -prüfung (2)
- Bundesoberbehörden (2)
- CEN/TC 352 Nanotechnologies (2)
- Case studies (2)
- Catalysts (2)
- Cathodoluminescence (2)
- CeO2 (2)
- Cell studies (2)
- Ceramics and Composites (2)
- Characterisation (2)
- Chemical admixtures (2)
- Chemical analysis (2)
- Chemical composition (2)
- Cleavable probe (2)
- Cluster (2)
- Coatings (2)
- Collection (2)
- Commercial graphene (2)
- Comparison (2)
- Complex (2)
- Composites (2)
- Concentration (2)
- Concrete (2)
- Convolutional neural networks (2)
- Correlative Imaging (2)
- Cr(III) (2)
- Cribellate spiders (2)
- Crosslinker (2)
- DNA radiation damage (2)
- Data conversion (2)
- Data curation (2)
- Data fitting (2)
- Data organization (2)
- Decision support (2)
- Desintegracion radioactiva (2)
- Diagnosis (2)
- Dielectric Spectroscopy (2)
- Dielectric spectroscopy (2)
- Diopside (2)
- Direct damage (2)
- Direct laser interference patterning (DLIP) (2)
- Direct laser-interference patterning (DLIP) (2)
- Discotic Liquid Crystals (2)
- Dispersion process (2)
- Dissociative electron attachment (DEA) (2)
- Dissociative electron transfer (DET) (2)
- Double-strand break (DSB) (2)
- Dynamic Light Scattering (2)
- EDX (2)
- EMN (2)
- EMPIR (2)
- EMPIR 18HLT01 MetVesII (2)
- ESCA (2)
- EU FP7 project NanoValid (2)
- Ecology (2)
- Ectrocatalysis (2)
- Electrocatalysis (2)
- Electrolysis (2)
- Elektronenmikroskopie (2)
- Engineered Nanomaterials (2)
- Enhancement strategy (2)
- European Metrology Networks (EMNs) (2)
- Evolution (2)
- Excitation (2)
- FAIR (2)
- FFT (2)
- FLIM (2)
- Fail-safe (2)
- Fast scanning calorimetry (2)
- Fe3O4 (2)
- FeNi (2)
- FeNi-Oxide NPs (2)
- Film thickness (2)
- Finite-difference time-domain calculations (2)
- Flame retardancy (2)
- Flow cytometry (FCM) (2)
- Fluorescence standard (2)
- Fluorescent particles (2)
- Fluoride (2)
- Force distance curve (2)
- Fourier Transform (2)
- Fourier transforms (2)
- Functionalization (2)
- Funtional Groups (2)
- Gallium doping (2)
- Gene five protein (2)
- Glass transition temperature (2)
- Glue (2)
- Graphene inks (2)
- Graphene powder (2)
- Graphitization (2)
- HDF5 (2)
- Halloysite nanotubes (2)
- Hard x-ray photoelectron spectroscopy (2)
- Herceptin (2)
- Hierarchical micro-nanostructures (2)
- High resolution (2)
- Holistic experimental procedures (2)
- Holistic experimentation (2)
- Holistic science (2)
- Homogeneity (2)
- Hydrated DNA (2)
- Hydrated electron (2)
- Hydration (2)
- Hydration shell (2)
- Hydrogen evolution reaction (2)
- Hydroxyectoine (2)
- Hydroxyl radical (2)
- ICP-MS (2)
- ILC (2)
- IR spectroscopy (2)
- IgG (2)
- Immunoassays (2)
- Immunocapture (2)
- Immunoglobulins (2)
- Immunoprecipitation (2)
- Immunosensor (2)
- In-situ (2)
- Indirect damage (2)
- Industrial applications (2)
- Instrument calibration (2)
- Interfaces (2)
- Interlaboratory Comparison (2)
- Interlaboratory Comparisons (2)
- Ionic Liquid Crystals (2)
- Ionisation (2)
- Ionization (2)
- Jahrestag (2)
- Kerbschlagarbeit (2)
- Kikuchi (2)
- Korrelation (2)
- Korrosion (2)
- Latex (2)
- Lattice parameters (2)
- Layer-by-layer deposition (2)
- Ligands (2)
- Lubrication (2)
- Material sciences (2)
- Measurement data conversion (2)
- Mesoporous (2)
- Metal cluster (2)
- Metal organic framework (2)
- Metals and Alloys (2)
- Method development (2)
- Method validation (2)
- Microanalysis (2)
- Microfluidics (2)
- Microparticle (2)
- Micropatterning (2)
- Microplastic (2)
- Microplastics (2)
- Molecularly Imprinted Polymers (2)
- Monitoring (2)
- Morphology (2)
- Multi photon lithography (2)
- Multilayer graphene (2)
- Multiphoton Lithography (2)
- Método de Montecarlo (2)
- NXsas (2)
- Nano- and microsensors (2)
- Nano-safety (2)
- Nanocarrier (2)
- Nanocharacterisation (2)
- Nanofasern (2)
- Nanoindentation (2)
- Nanomechanics (2)
- Nanometrology (2)
- Nanopulver (2)
- Nanorisk (2)
- Nanosensor (2)
- Nanostructure investigation (2)
- Natural rubber (2)
- NeXus (2)
- Near ambient pressure xray photo electron spectroscopy (2)
- Net-ionization reaction (2)
- Neural networks (2)
- Neutron (2)
- Neutron scattering (2)
- Niobium (2)
- Non-spherical shape (2)
- OECD TG 124 (2)
- OER (2)
- Oberflächenfunktionalisierung (2)
- Optical Spectroscopy (2)
- Optical probe (2)
- Oriented immobilization (2)
- Osmolyte (2)
- Oxygen (2)
- PAG (2)
- PDT (2)
- PEG (2)
- PFAS (2)
- Particle number concentration (2)
- Particle scattering simulation (2)
- Particle size and shape distribution (2)
- Particle size distributuion (2)
- Particle surface analysis (2)
- Particle synthesis (2)
- Partikel (2)
- Partikelgrößenverteilung (2)
- Peptide (2)
- Peptide Library (2)
- Performance validation (2)
- Permethrin (2)
- Perovskite (2)
- Ph (2)
- Phosphor (2)
- Photocuring (2)
- Photonic crystal (2)
- Photoresist (2)
- Plant Science (2)
- Polydopamine (2)
- Polymer blends (2)
- Polymer nanocomposites (2)
- Polymer particle (2)
- Polymer-based nanocomposites (2)
- Polymers of Intrinsic Microporosity (2)
- Polypropylene (2)
- Polysaccharides (2)
- Power density (2)
- Prehydrated electron (2)
- Presolvated electron (2)
- Protein A (2)
- Proximity-enhanced reaction (2)
- Pump-probe experiments (2)
- Quantitative Analysis (2)
- Quantum yields (2)
- Quasi-direct damage (2)
- Radical (2)
- Radical scavenger (2)
- Radioactive nanoparticle (2)
- Ratio refinement (2)
- Reactive oxygen species (2)
- Recycling (2)
- Reference Material (2)
- Reliability (2)
- Reproducibility crisis (2)
- Rheology (2)
- Robotics (2)
- Rosin (2)
- SANS (2)
- SBA-15 (2)
- SIMS (2)
- SZ2080 negative photo-resist (2)
- Safety (2)
- Saxs (2)
- Scanning electron microscopy (2)
- Scicat (2)
- Secondary ion mass spectrometry (2)
- Self-assembly (2)
- Self-organization (2)
- SiGe (2)
- Silane (2)
- Silanization (2)
- Silica and Polystyrene Particles (2)
- Silica and polystyrene nanoparticles (2)
- Silica nanoparticles (2)
- Silicon (2)
- Silver nanoparticle (2)
- Single-strand break (SSB) (2)
- Special issue (2)
- Spectroscopic Ellipsometry (2)
- Spectroscopic imaging ellipsometry (2)
- Stakeholder (2)
- Standardisierung (2)
- Starch (2)
- Starch nanoparticle (2)
- Steel (2)
- Structure-property relationship (2)
- Struvite (2)
- Surface Analysis (2)
- Surface Group Analysis (2)
- Surface charge (2)
- Surface morphology (2)
- Surface oxidation (2)
- Sustainability (2)
- Synchrotron radiation (2)
- Sythesis (2)
- TED-GC/MS (2)
- TGA (2)
- TKD (2)
- Temeprature scaling (2)
- Temperature scaling (2)
- Test material (2)
- Thermoanalytik (2)
- Thermoplastics (2)
- Thin polymer films (2)
- TiAl64V (2)
- Time-of-flight secondary ion mass spectrometry (ToF-SIMS) (2)
- Titania (2)
- Titanium alloy (2)
- Titration (2)
- Transmission electron microscopy (TEM) (2)
- Transparency (2)
- Transparent Conductive Oxides (2)
- Two photon polymerisation (2)
- Ultra thin polymer films (2)
- Uncertainties (2)
- Virus inhibition (2)
- Volume specific surface area (2)
- WAXS (2)
- White light interference microscopy (2)
- X-ray diffraction (2)
- X-ray spectroscopy (2)
- XANES (2)
- Xray (2)
- Xray photo electron spectrocopy (2)
- Zeta potential (2)
- Zinc oxide (2)
- fluorescence (2)
- low energy electrons (2)
- nanoparticula (2)
- pH (2)
- qNMR (2)
- (Hard) X-ray Photoelectron Spectroscopy (1)
- 100Cr6 (AISI 52100) steel (1)
- 18HLT01 MetVes II (1)
- 2D (1)
- 2D flakes (1)
- 2D nanomaterial (1)
- 2D nanoparticle (1)
- 3D FFT (1)
- 3D etching (1)
- 3D printed hydrogel (1)
- 3D-printing (1)
- 3d structuring (1)
- 60-230V (1)
- AAAA (1)
- ACCORDs (1)
- ADA-GEL (1)
- AEROSIL® OX50 (1)
- AFM based test methods (1)
- AFM force distance curves (1)
- AFM force spectroscopy (1)
- AFM friction analysis (1)
- AFM plastic deformation (1)
- AFM stiffness of interface (1)
- AFM-IR (1)
- AFM-Kraft-Abstand-Kurven (1)
- AI tool (1)
- AIS QD (1)
- ASAXS (1)
- ATH (1)
- ATZ (1)
- Aantimicrobial (1)
- Ab initio calculations (1)
- Absolute measurement (1)
- Absorption (1)
- Active Matter (1)
- Actuating materials (1)
- Additiv (1)
- Additive (1)
- Adhesion (1)
- Adhesives (1)
- Advanced optics (1)
- Ag (1)
- Ag2S (1)
- AgInS (1)
- Aggregation induced emission (1)
- Al-Composite (1)
- Al-based alloy (1)
- Al2O3 thin films (1)
- AlOOH (1)
- Albumin (1)
- Alloy 36 (1)
- Alpha (1)
- Alumina toughened zirconia (1)
- Aluminium alloy (1)
- Aluminium nitride (1)
- Aluminiumoxid (1)
- Amphiphilicity (1)
- Analyses (1)
- Analysis approach (1)
- Analytical chemistry (1)
- Analytical methods (1)
- Analytical scanning electron microscopy (1)
- Analytical services (1)
- Analytische Zentrifuge (1)
- Anatase (1)
- Aneurism (1)
- Anhydrite (1)
- Anisotropy (1)
- Antiadhesive surfaces (1)
- Antibacterial properties (1)
- Antibacterial surfaces (1)
- Antibakterielle Oberflächen (1)
- Antibiotic delivery (1)
- Antibiotic release (1)
- Antibodies (1)
- Antibody-gated indicator delivery (1)
- Antifouling (1)
- Antikörper (1)
- Antimicrobial resistance (1)
- Antimicrobial titanium coating (1)
- Antioxydant (1)
- Antiviral activity (1)
- Aqueous quantum dot (1)
- Aqueous synthesis (1)
- Arbitrary shapes (1)
- Argon gas cluster ion sputtering (1)
- Aromatische Aminosäureanalytik (1)
- Article concentration (1)
- Artificial Intelligence (1)
- Artificial digestion (1)
- Artificial intelligence (1)
- Atomic force microscope (1)
- Atomic fraction (1)
- Au Nanoparticles (1)
- Au nanodisks (1)
- Au nanoparticles (1)
- Au-nanocubes (1)
- Augenbohne (1)
- Auger Electron Spectroscopy (1)
- Auger electron spectroscopy (1)
- Automated Image Analysis (1)
- Automated analysis (1)
- Automated assay (1)
- Autonomous Materials Discovery (1)
- Aza-BODIPY (1)
- BADGER film (1)
- BAM Academy (1)
- BCA (1)
- BMU (1)
- BNP (1)
- BODIPY (1)
- BODIPY probe (1)
- BSA (1)
- BTS (1)
- Bacteria repellent surfaces (1)
- Bacteria-repellent surfaces (1)
- BadgerFilm (1)
- Basidiomycetes (1)
- Bassanite (1)
- Bead-based assays (1)
- Benchmarking (1)
- Bessel-Strahlen (1)
- Bimetallic noble metal nanoparticles (1)
- Bimodal (1)
- Bimodal size distribution (1)
- Bio-ceramic engineering (1)
- Bio-orthogonal chemistry (1)
- Biochip (1)
- Biofilme (1)
- Biofilms (1)
- Biofunctional Molecules (1)
- Bioinspiration (1)
- Biomaterials (1)
- Biomimetic (1)
- Biomimetic surfaces (1)
- Bionic materials (1)
- Bioresorbable Biomaterials (1)
- Biosensing (1)
- Biosensors (1)
- Bipyramid (1)
- Black phosphorus (1)
- Bloch wall (1)
- Boehmit nanoparticle (1)
- Boehmite alumina (1)
- Boehmite nanoparticles (1)
- Bone screws (1)
- Bone tissue engineering (1)
- Boronic acid (1)
- Boronic acid-functionalized 2D MoS2 (1)
- Bradford-Assay (1)
- Bragg peak (1)
- Broadband dielectric microscopy (1)
- Brown-rot fungi (1)
- Brownian motion (1)
- Brownsche Molekularbewegung (1)
- Building and Construction (1)
- Bulk metallic glasses (1)
- Bulk temperature (1)
- Bystander effect (1)
- Böhmit (1)
- C++ (1)
- C-F bond activation (1)
- C7H15N2O4P (1)
- CCQM (Consultative Committee for Amount of Substance) (1)
- CE-ICP-MS (1)
- CEN (1)
- CO2 (1)
- CRP (1)
- CUINS2 nanocrystals (1)
- Calamistrum (1)
- Calcium sulfoaluminate (CSA) cement (1)
- Calibrated fluorescence measurements (1)
- Calibration structure (1)
- Cancer therapy (1)
- Carbon (1)
- Carbon Nanomembranes (1)
- Carbon black (1)
- Carbon dot (1)
- Carbon fibers (1)
- Carbon footprint (1)
- Carbon ions (1)
- Carbon nanoparticles (1)
- Carbon storage (1)
- Carrier protein (1)
- Catalogue of Services (CoS) (1)
- Catalogue of services (1)
- Catalyst (1)
- Catalyst layer (1)
- Catch and release assay (1)
- Cationic photocuring (1)
- Causes leading to scientific misconduct (1)
- CdS (1)
- CdTe quantum dots (1)
- Ce0.1Zr0.9O2 nanoparticles (1)
- Ce0.25Zr0.75O2 nanoparticles (1)
- Ce0.5Zr0.5O2 nanoparticles (1)
- Ce0.75Zr0.25O2 nanoparticles (1)
- Ce0.9Zr0.1O2 (1)
- CeO2 nanoparticles (1)
- CeO2/Co3O4 (1)
- Cell appendages (1)
- Cell size (1)
- Cell-repellent surfaces (1)
- Cells (1)
- Cellulose acetate (1)
- Cellulose nanofibrils (1)
- Ceramic matrix composites (1)
- Ceramic microprinting (1)
- Ceramic nano particles (1)
- Ceramics (1)
- Ceramics 3D printing (1)
- Cerium oxide (1)
- Certified Referencematerial (1)
- Certified reference materials (1)
- Certified reference nanomaterials (1)
- Ceruloplasmin (1)
- Cetrifugal Liquid Sedimentation CLS (1)
- Channel access (1)
- Characterization method (1)
- Charge (1)
- Charge transfer (1)
- Chemical analyses (1)
- Chemiluminescence (1)
- Chemistry (1)
- Chemometric analysis (1)
- Chromium (III) complexes (1)
- Civil and Structural Engineering (1)
- Classification (1)
- Cleavable linker (1)
- Cleavable probes (1)
- Click chemistry (1)
- Climate (1)
- Cmake (1)
- Co (1)
- Co0.75Fe2.25O4 nanoparticles (1)
- Co1.5Fe1.5O4 nanoparticles (1)
- Co2.25Fe0.75O4 nanoparticles (1)
- Co3O4 nanoparticles (1)
- Coaggregation (1)
- Coatings and Films (1)
- Cobalt (1)
- Coherent exchange (1)
- Colloidal semiconductor nanocrystals (1)
- Color (1)
- Color tuning (1)
- Combinatorial peptide library (1)
- Command line (1)
- Command-line interface (1)
- Commercialization (1)
- Comparability (1)
- Comparability of Measurement Results (1)
- Compatible solute (1)
- Complementary methodology and metrology (1)
- Complementary methods (1)
- Complex-shape (1)
- Composition (1)
- Compound semiconductors (1)
- Compund semiconductors (1)
- Computed tomography (1)
- Computertomographie (1)
- Conference (1)
- Confined catalyst (1)
- Confocal raman imaging (1)
- Conjugate (1)
- Contrast agent (1)
- Controlled morphology (1)
- Controlled periodic illumination (1)
- Converter marterial (1)
- Converter material (1)
- Copper (1)
- Coprecipitation (1)
- Core-shell nanoparticle (1)
- Core-shell nanoparticle (CSNP) (1)
- Core-shell particles (1)
- Core-shell structures (1)
- Core/shell materials (1)
- Core/shell nanoparticle (1)
- Core/shell quantum dot (1)
- Core–shell particles (1)
- Correlative Spectroscopy (1)
- Corrosion rate (1)
- Coulomb explosion (1)
- Covalend functionalization (1)
- Covalent Organic frameworks (1)
- Covalent functionalization (1)
- Covalent interactions (1)
- Cr(III) complex (1)
- Critical strain (1)
- Cross-sectioning (1)
- Crosslink density control (1)
- Crosslinking (1)
- Crosslinking density (1)
- CuNPs (1)
- Cubical Iron Oxide (1)
- Cubical shape (1)
- Curie temperature (1)
- Curing (1)
- Curve fitting (1)
- Cycloaliphatic epoxy oligosiloxane (1)
- Cyclometalated iridium (III) complexes (1)
- DFT (1)
- DFT calculations of Raman spectra (1)
- DMAS (1)
- DMSO (1)
- DNA structures (1)
- DNA-Binding protein (1)
- DPA (1)
- DRIFTS (1)
- DSB (1)
- DSC (1)
- DTAB (1)
- Damage (1)
- Damping factor (1)
- Data Fusion (1)
- Data Management (1)
- Data analysis round robin (1)
- Data catalog (1)
- Data corrections (1)
- Data correlation (1)
- Data management (1)
- Data manipulation (1)
- Data pipelines (1)
- Data processing (1)
- Data provenance (1)
- Data readiness level (1)
- Data stewartship (1)
- Data visualisation (1)
- Databases (1)
- Datasets (1)
- Datenfusion (1)
- Debian (1)
- Debye scattering equation (1)
- Debye-Waller-Faktor (1)
- Decay kinetics (1)
- Defect Analysis (1)
- Defect photoluminescence (1)
- Definition (1)
- Definition of nanomaterial (1)
- Degradation signatures (1)
- Degradation studies (1)
- Demonstration (1)
- Dendritic polyglycerol (1)
- Density (1)
- Depth profiling (1)
- Deuterium (1)
- Diagnostic antibodies (1)
- Diclofenac (1)
- Diffractive gratings (1)
- Digestion (1)
- Digital laboratory (1)
- Digitalisation (1)
- Digitalisierung (1)
- Digitalization (1)
- Dimensional mismatch of crystalline lattice periods (misfit) (1)
- Diopsid (1)
- Direct Laser Writing (1)
- Direct laser interference patterning (1)
- Dispersion (1)
- Dispersion of nano materials (1)
- Dissolution (1)
- Distribution of nanoparticles (1)
- Domain wall (1)
- Doping (1)
- Drug delivery (1)
- Dual sensing (1)
- Durability (1)
- Dyad molecules (1)
- Dye labeling (1)
- Dyes (1)
- Dynamic behavior (1)
- Dynamic heterogeneity (1)
- Dynamische Lichtstreuung (1)
- Dünne Schichten (1)
- E. coli (1)
- EC nanomaterial definition (1)
- EDS-TM002 (1)
- ELISA (1)
- EMPIR nPSize (1)
- EMPIR project (1)
- EPICS (1)
- EPMA (Electron Probe Microanalysis) (1)
- EU (1)
- EXAFS (1)
- Ectoine hydration (1)
- Editorial (1)
- Education (1)
- Elastin (1)
- Elastomer (1)
- Electric Safety Interlock (1)
- Electrical Paramters (1)
- Electrical Properties (1)
- Electrical conductivity (1)
- Electrical properties (1)
- Electrical thin layers (1)
- Electrocatalytic Water Splitting (1)
- Electrochemical Degradation (1)
- Electrochemical Titration (1)
- Electrochemical catalysts (1)
- Electrochemical sensing (1)
- Electrochemical treatment (1)
- Electromagnetic radiation (1)
- Electromagnetic theories (1)
- Electron Probe Microanalysis (1)
- Electron Probe Microanalysis (EPMA) (1)
- Electron backscattering diffraction (EBSD) (1)
- Electron beam-induced fragmentation (1)
- Electron density map (1)
- Electron probe microanallysis (EPMA) (1)
- Electron probe microanalysis (1)
- Electron spectroscopy (1)
- Electron tomography (1)
- Electronic, Optical and Magnetic Materials (1)
- Electrons (1)
- Electrospun fibers (1)
- Electrospun nanocomposite fiber (1)
- Elektronisches Laborbuch (1)
- Ellipsometric porosimetry (1)
- Ellipsometrie (1)
- Emission enhancement (1)
- Encapsulation (1)
- Endpoints (1)
- Energiedissipation im Kontakt (1)
- Energy materials (1)
- Engineered nanomaterials (1)
- Environmental Chemistry (1)
- Epoxi nanocomposites (1)
- Epoxy conversion degree (1)
- Epoxy-Anhydrid Duroplast (1)
- Escherichia coli (1)
- Estrogenic activity of plastic nanoparticles (1)
- Etofenprox (1)
- European Metrology Network (1)
- European Metrology Network for Advanced Manufacturing, Strategic Research Agenda (1)
- European funding strategies (1)
- Ex-situ (1)
- Exchange length (1)
- Exfoliation (1)
- Experiment tracking (1)
- Experimental traceability (1)
- Expert system (1)
- Extracellualr vesicles (1)
- Extracellular matrix (1)
- F pili (1)
- FAIRification (1)
- FLASH effect (1)
- FTIR spectroscopy (1)
- Fabrication parameters (1)
- Fe (1)
- Fe-Ni (1)
- Fe2O3 nanoparticles (1)
- FeNi nanoparticles (1)
- FeNi thin film (1)
- Femtosecond laser-processing (1)
- Fermi resonance (1)
- Ferrihydrite (1)
- Ferumoxytol (1)
- Fiber toxicology (1)
- Field of view (1)
- Field sensor (1)
- Filled rubbers (1)
- Filled thermosets and plastics (1)
- Finite element analysis (1)
- Finite-difference time-domain calculations (FDTD) (1)
- Fire Retardant (1)
- Fityk (1)
- Flame retardant (1)
- Flammability (1)
- Flexural rigidity (1)
- Flourescence (1)
- Fluorescence intensity ratio (1)
- Fluorescence microscopy (1)
- Fluorescence quantum yield (1)
- Fluorescence spectroscopy (1)
- Fluorescent glasses (1)
- Fluorescent indicator (1)
- Fluorescent label (1)
- Fluorides (1)
- Fluorolytic sol-gel synthesis (1)
- Fluoropolymers (1)
- Focused Ion Beam (1)
- Focussed ion beam (1)
- Food Science (1)
- Force distance curves (1)
- Force-distance curves (1)
- Force-distance-curve (1)
- Form factor (1)
- Forschungsstrategie (1)
- Free electron laser (FEL) (1)
- Freeze casting (1)
- Fresnoit (1)
- Frozen state photopolymerization (1)
- Fullerene (1)
- Fullerite (1)
- Fully aromatic frameworks (1)
- Functional fatigue (1)
- Functional group (1)
- Functional group analysis (1)
- Functional properties (1)
- Functionalized Nanomaterials (1)
- Functionalized nano- and microparticles (1)
- Functionalized nanographene (1)
- Functionalized silica and polymeric particles (1)
- Gadolinium (1)
- Gamma (1)
- Gamma ray (1)
- Gas separation membranes (1)
- Gas sorption (1)
- Gastrointestinal barrier (1)
- Gated hybrid material (1)
- Gel (1)
- General Chemistry (1)
- General Medicine (1)
- Geology (1)
- Git (1)
- Glass Ceramic (1)
- Glass ceramic (1)
- Glass-ceramic (1)
- Glow-discharge optical emission spectroscopy (1)
- Gold Nanoparticle (1)
- Gold nanoclusters (1)
- Gold-Nanopartikel (1)
- Governance (1)
- Grafting (1)
- Grain orientation (1)
- Granulometrie (1)
- Graphen Oxide (1)
- Graphene /-oxide (1)
- Graphene funcionalisation (1)
- Graphene functionalisation (1)
- Graphene functionalization (1)
- Graphene related materials (1)
- Graphene related two-dimensional materials (GR2M) (1)
- Graphene template (1)
- Graphene-based polyglycerol sulfates (1)
- Graphene-related 2D materials (1)
- Graphhene (1)
- Graphs (1)
- Green synthesis (1)
- Grenzfläche als Material (1)
- Größe (1)
- Größenbestimmung (1)
- Guanidine receptor (1)
- Gypsum' SAXS (1)
- HEA (1)
- Hard X-ray photoelectron spectroscopy (1)
- Heat maps (1)
- Heat-resistant nickel alloys (1)
- Hematite (1)
- Heterogeneous catalysis (1)
- Hexagonally-arranged nano-protrusions (1)
- Hierarchical porosities (1)
- Hierarchical structures (1)
- Hierarchically porous (1)
- High Resolution (1)
- High pressure (1)
- High-resolution (1)
- High-resolution transmission electron microscopy (1)
- High-throughput (1)
- High-throughput measurements (1)
- History (1)
- Holistic experiment approaches (1)
- Holzschutzmittel (1)
- Homogeneous deposition (1)
- Human antibodies (1)
- Human factor (1)
- Human influence (1)
- Hybrid metrology measurement (1)
- Hydrodynamics (1)
- Hydrogen Generation (1)
- Hydrogenated nanostructures (1)
- Hydrothermal synthesis (1)
- Hygiene (1)
- Hyperbranched (1)
- Hyperspectral imaging (1)
- ICP-OES (1)
- IR (1)
- IR oxide (1)
- ISO 21363 (1)
- ISO 23173 (1)
- ISO/TC 201 (1)
- ISO/TC 202 Microbeam Analysis (1)
- ISO/TC229 (1)
- ISOGScope (1)
- Identification (1)
- ImAFM (1)
- Image Segmentation (1)
- Image manipulation (1)
- Images (1)
- Imaging Ellipsometry (1)
- Imaging ellipsometry (1)
- Imaging surface chemical analysis (1)
- Imaging techniques (1)
- Immobilisierung (1)
- Immobilization (1)
- Immunoaffinity extraction (1)
- Immunpräzipitation (1)
- Implant material (1)
- In situ (1)
- In situ Atomic Force Microscopy (AFM) (1)
- In situ synthesis (1)
- In vivo imaging (1)
- In-situ scattering (1)
- Indenter area function (1)
- Indium Tin Oxide (1)
- Industrial and Manufacturing Engineering (1)
- Industrial application (1)
- Inelastic background (1)
- Inelastic neutron scattering (1)
- Inflammation (1)
- Influenza A virus (1)
- Infrared nano AFM (1)
- Infrastructure (1)
- Insecticide (1)
- Instrument automation (1)
- Instrument compliance (1)
- Instrument control (1)
- Instrumentation utilization (1)
- Inter-laborator comparison (1)
- Inter-laboratory comparisons (1)
- Intercomparability (1)
- Interlaboratory (1)
- Interlaboratory comparability (1)
- Interlaboratory comparisons (1)
- Interlabority comparison (1)
- Intermixing (1)
- Intermodulation (1)
- Intermodulation-AFM (1)
- Interpenetrating polymer networks (1)
- Intrinsic OER activity (1)
- Iodine (1)
- Ion beam erosion Sectioning (1)
- Ion beam therapy (1)
- Iridium oxide (1)
- Iron (1)
- Iron carbide (1)
- Iron nanoparticles (1)
- Iron nanophases (1)
- Iron nitride (1)
- Irreversible adsorption (1)
- JNP (1)
- JNP AdvManuNet (1)
- K+ doped (1)
- K-rich Birnessite (K0.45MnO2) (1)
- Kidney injury (1)
- Knowledge (1)
- Kunststoff (1)
- LET (1)
- LEVASIL 50/50 (1)
- LL equation (1)
- Label (1)
- Laboratory methodology (1)
- Landau Lifshitz Gilbert equation (1)
- Landau de-Gennes analysis (1)
- Lanthanide(III) (1)
- Lanthanides (1)
- Large number of participants (1)
- Laser (1)
- Laser Metal Deposition (LMD) (1)
- Laser damage (1)
- Laser direct writing (1)
- Laser light scattering (1)
- Laser nanostructuring (1)
- Laser technology (1)
- Laser writing (1)
- Laser-Materialbearbeitung (1)
- Laser-induced Periodic Surface Structures (LIPSS) (1)
- Laser-induced amorphization (1)
- Laser-induced micro- and nanostructures (1)
- Laser-induced nanostructures (1)
- Laser-induced pariodic surface structures (1)
- Laser-induced periodic surface structueres (LIPPS) (1)
- Laser-induced periodic surface structures (1)
- Laser-induzierte periodische Oberflächen-Nanostrukturen (1)
- Laser-induzierte periodische Oberflächenstrukturen (1)
- Laser-modified surface (1)
- Lateral dimensions (1)
- Lateral flow (1)
- Lateral flow assay (1)
- Lateral flow test (1)
- Layer Materials (1)
- Layer system (1)
- Layered manganese oxide (1)
- Lead-free (1)
- Legionella (1)
- Leichtbau (1)
- Lichtstreuung (1)
- Lifetime analysis (1)
- Ligand exchange (1)
- Ligand quantification (1)
- Lignin (1)
- Linux (1)
- Liquid-liquid-phase-separation (1)
- Literature survey (1)
- Llifetime (1)
- Lonic liquid (1)
- Lorenz transmission electron microscopy (1)
- Low Reynolds number swimmers (1)
- Low-loading (1)
- Lubricant additives (1)
- Luminescence lifetime measurments (1)
- Luminescent lifetime (1)
- Luminescent materials (1)
- MCNP (1)
- MIC (1)
- MNP production technique (1)
- MOVPE (1)
- MPI (1)
- MPLS (1)
- MRT (1)
- Macrophage (1)
- Magic-sized cluster (1)
- Magnet coupling (1)
- Magnetic (1)
- Magnetic Nanoparticles (1)
- Magnetic anisotropy (1)
- Magnetic beads (1)
- Magnetic interacion (1)
- Magnetic nanoparticle (1)
- Magnetic resonance imaging (1)
- Magnetic swimmers (1)
- Magnetization dynamics (1)
- Magnetron Sputtering (1)
- Martin Seah (1)
- Mass spectrometry (1)
- Material chemistry (1)
- Material defects (1)
- Material-binding Peptides (1)
- Materials Chemistry (1)
- Materials Design (1)
- Materials and Processes Data Reusability (1)
- Materials science (1)
- Matrix (1)
- Matter reorganization (1)
- Matter reorganization theories (1)
- Me-TiO2 (1)
- Measurement methodology (1)
- Measurement science (1)
- Mechanical testing (1)
- Median lethal energy deposit (1)
- Medical implants (1)
- Mesocrystal (1)
- Mesoporous Materials (1)
- Mesoporous SiO2-CaO nanoparticles (1)
- Mesoporous iridium-titanium mixed oxides (1)
- Mesoporous particles (1)
- Mesoporous phosphate-based glasses (1)
- Meta material (1)
- Metadata (1)
- Metadata collection (1)
- Metadata structuring (1)
- Metal (1)
- Metal carbides (1)
- Metal fluorides (1)
- Metal organic frameworks (1)
- Metal-organic frameworks (1)
- Metal-semiconductor (1)
- Metal–organic framework (1)
- Metasurface (1)
- Methodology development (1)
- Methos comparision (1)
- Metrics (1)
- Metrological traceability (1)
- Metrology in Chemistry and Biology (1)
- Micelle (1)
- Micro- and Nanoplastics (1)
- Microarray (1)
- Microarray printing (1)
- Microbial adhesions (1)
- Microfabrication (1)
- Microfluids (1)
- Microorganism (1)
- Microparticles (1)
- Microplastic reference materials (1)
- Microstructure evolution (1)
- Microtribology (1)
- Microwave synthesis (1)
- Microwave-assisted synthesis (1)
- Mie resonances (1)
- Mikrostrukturen (1)
- Mitochondria (1)
- Mixed metal oxide (1)
- Model (1)
- Modulus (1)
- Molecular Dynamics (1)
- Molecular Mobility (1)
- Molecular mobility (1)
- Molecularly imprinted polymers (1)
- Monomer (1)
- Monte carlo (1)
- Monte-Carlo (1)
- Morpho-chemical characterization (1)
- Motor controller (1)
- Multi-photon light structuring (1)
- Multi-resistant bacteria (1)
- Multi-sample analysis (1)
- Multi-scale (1)
- Multi-scale measurements (1)
- Multicolored (1)
- Multifunctional nanoparticles (1)
- Multiphoton laser structuring (1)
- Multivalency (1)
- Mussel inspired materials (1)
- Mussel-inspired adhesives (1)
- Mussel-inspired coating (1)
- Mussel-inspired materials (1)
- Mutual calibration (1)
- NFDI (1)
- NIR-II Imaging (1)
- NIR-II fluorescence (1)
- NIRII (1)
- NaCl-Methode (1)
- Nafion 117 (1)
- Naica (1)
- Nanaoparticle (1)
- Nano CRM (1)
- Nano Characterisation (1)
- Nano characterization (1)
- Nano material (1)
- Nano screening (1)
- Nano structure (1)
- Nano-ceramic-additive-manufacturing photoresin (1)
- Nano-characterisation (1)
- Nano-object (1)
- Nano-related data (1)
- Nano-risk assessment (1)
- NanoCAM (1)
- NanoValid (1)
- Nanoanalysis (1)
- Nanoanalytics (1)
- Nanobiointerfaces (1)
- Nanocasting (1)
- Nanocomposite fibers (1)
- Nanocubes (1)
- Nanodiamant (1)
- Nanodielectrics (1)
- Nanodosimetry (1)
- Nanofiller (1)
- Nanokomposit (1)
- Nanomaterial Properties (1)
- Nanomaterial analysis (1)
- Nanomaterial categorisation (1)
- Nanomaterial definition (1)
- Nanomaterial design (1)
- Nanomaterial legislation (1)
- Nanomaterial properties (1)
- Nanomaterial regulation (1)
- Nanomechanical charecteisation (1)
- Nanomechanical properties (1)
- Nanon (1)
- Nanoparticle Characterization (1)
- Nanoparticle characterization (1)
- Nanoparticle size distribution (1)
- Nanoparticle size measurement (1)
- Nanoparticles Synthesis and Characterization (1)
- Nanoparticular TiO2 (Anatase) (1)
- Nanopipette modification (1)
- Nanoplatelet (1)
- Nanoplatform (1)
- Nanoplattform (1)
- Nanoporous (1)
- Nanopowder (1)
- Nanopropous materials (1)
- Nanorisk Governance (1)
- Nanosafety services (1)
- Nanoscale (1)
- Nanoscale luminescent reporters (1)
- Nanoscale measurements (1)
- Nanoscience (1)
- Nanosensors (1)
- Nanosilica (NS) (1)
- Nanosilver (1)
- Nanostrcutures (1)
- Nanostructural analysis (1)
- Nanostructured FeOx films (1)
- Nanostrukturen (1)
- Nanotechnologie (1)
- Nanotechnologies (1)
- Nanotoxicity (1)
- Nanotribology (1)
- Nanowear (1)
- Native oxide layer (1)
- Nd excitation (1)
- Near-field spectroscopy (1)
- Neel wall (1)
- Network (1)
- Neuartige Materialien (1)
- Neural Networks (1)
- Neutron Scattering (1)
- Neutron imaging (1)
- Next Generation Sequencing (1)
- Ni (1)
- Ni-Mn-Ga (1)
- Nichtrostender Stahl (1)
- Nickel (1)
- Nile Red (1)
- Nitrene[2+1]cycloaddition (1)
- Nitrogen (1)
- Nnano particle (1)
- Noble metal nanoparticles (1)
- Non-classical crystallization (1)
- Non-destructive ambient analysis (1)
- Non-destructive testing (1)
- Non-spherical nanoparticles (1)
- Non-thermally coupled levels (1)
- Non-vitriolic iron-gall inks (1)
- Nonclassical crystallization (1)
- Nonlinear lithography (1)
- Normung (1)
- Nuclear Energy and Engineering (1)
- Nucleus (1)
- Numerical simulations (1)
- OECD TG (1)
- OECD TG 125 (1)
- OH (1)
- OMS (1)
- Oberflächenanalytik (1)
- Oberflächenintegrität (1)
- Oberflächenmesstechnik (1)
- Oberflächenmodifikation (1)
- Oberflächenpotential (1)
- Oberflächensteifigkeit (1)
- Ontologies (1)
- Open data on zenodo (1)
- Operating Procedure (1)
- Optical Assays (1)
- Optical analysis (1)
- Optical birefringence (1)
- Optical constants (1)
- Optical detection (1)
- Optical flow (1)
- Optical measurement technology (1)
- Optical measurements (1)
- Optical near field (1)
- Optical properties (1)
- Optical scattering (1)
- Optical temperature sensing (1)
- Optical tweezers (1)
- Optically active surfaces (1)
- Oral uptake (1)
- Ordered mesoporous carbon (1)
- Organic phosphates (1)
- Organic–inorganic nanostructures (1)
- Origami (1)
- Osteogenesis (1)
- Oxygen evolution reaction (OER) (1)
- Oxygen sensing (1)
- Oxygen sensitive (1)
- P25 (1)
- PC characterisation (1)
- PES (1)
- PH (1)
- PH probe (1)
- PVDF-Based membrane (1)
- Paint (1)
- Pair distribution function (1)
- Paper mills (1)
- Paramagnetism (1)
- Parameter correlation. (1)
- Participatory Approach (1)
- Particle accretion (1)
- Particle architecture (1)
- Particle scatterin simulations (1)
- Particle sensors (1)
- Particle shape (1)
- Particle size determination (1)
- Particle transfer (1)
- Particle, imaging (1)
- Partikeldurchmesser (1)
- Partikelgröße (1)
- Partikelgrößenbestimmung (1)
- Partikelkonzentration (1)
- Passivation shell (1)
- Pd(II) (1)
- Peem (1)
- Pelletization (1)
- Peptide binder (1)
- Peptides (1)
- Perfluorooctanoic Acid (PFOA) (1)
- Performance check (1)
- Perovskites (1)
- Pesticide (1)
- Pflanzenvirus (1)
- Phage Display (1)
- Phase transition (1)
- Phase transitions (1)
- Phenothrin (1)
- Phosphinine (1)
- Photodynamic therapy (1)
- Photoelectrochemistry (1)
- Photoluminescence quantum yield (1)
- Photon bunching (1)
- Photonics (1)
- Photons (1)
- Photooxidation (1)
- Photophysic (1)
- Photopolymer (1)
- Photoreforming (1)
- Photostability (1)
- Physical and theoretical chemistry (1)
- Physicochemical characterization (1)
- Pigments (1)
- Pitfalls (1)
- Plant virus (1)
- Plasma deposition (1)
- Plasmon enhancement (1)
- Plasmon resonance (1)
- Plasmonic nanofocusing (1)
- Plasmonic nanofocusing spectroscopy (1)
- Plastic reference materials (1)
- Plastics (1)
- Plastikstrategie (1)
- Platinum-ruthenium colloid (1)
- Polarimetry (1)
- Pollution (1)
- Polybutadiene/chloroprene (1)
- Polydispersity (1)
- Polyethylene (1)
- Polyethylene Glycol (1)
- Polyethylene glycol (1)
- Polyethylene glycol diacrylate (1)
- Polyethylene terephthalate (1)
- Polymer analysis/characterization (1)
- Polymer based Nanocomposites (1)
- Polymer electrolyte fuel cell (1)
- Polymer foils (1)
- Polymer nanocomposite (1)
- Polymer-binding Peptides (1)
- Polymer-ceramic mixtures (1)
- Porous carbon (1)
- Porous carbons (1)
- Porphyrin (1)
- Portable sensor (1)
- Position of carboxylate group (1)
- Post-modification by L-cysteine (1)
- Postfluorination (1)
- Potentiometry (1)
- Powder (1)
- Powder X-ray diffraction (1)
- Powder processing (1)
- Power Electronics (1)
- Power electronics (1)
- Pphotophysics (1)
- Practical aspects (1)
- Pre-standardisation (1)
- Preceramic polymer (1)
- Precipitation (1)
- Preparation (1)
- Primer (1)
- Principle component analysis (1)
- Prodrug antibiotic (1)
- Production (1)
- Proficiency test (1)
- Propolis (1)
- Protection (1)
- Protein structure (1)
- Prürfrichtlinie (1)
- Pt(II) (1)
- Pump-probe (1)
- Purification (1)
- Pycnometry (1)
- Pyrethroid (1)
- QNMR (1)
- QUASES (1)
- Qantum yield (1)
- Quality assurcance (1)
- Quality control (1)
- Quality infrastructure (1)
- Quantitative surface chemical analysis (1)
- Quantum Dots (1)
- Quantum Yields (1)
- Quantum do (1)
- Quantum rod (1)
- Quartz nanopipettes (1)
- Quarzglas (1)
- RBE (1)
- REACH (1)
- RNA (1)
- Radiation (1)
- Radiation protection (1)
- Radical Scavenge (1)
- Radioactive NP (1)
- Raman spectroscopy (1)
- Ratiometric (1)
- Ratiometric Sensors (1)
- Real time growth control (1)
- Real-time infrared spectroscopy (1)
- Recycling-by-design (1)
- Reference Method (1)
- Reference Nanomaterials (1)
- Reference methods (1)
- Reference nanomaterials (1)
- Reference nanoparticles (1)
- Reference particles (1)
- Reference procedures (1)
- Reference products (1)
- Reference standards (1)
- Reference structure (1)
- Referenzdaten (1)
- Regeneration (1)
- Regional workshop (1)
- Reibungsreduktion (1)
- Reinforcement (1)
- Release (1)
- Release kinetics (1)
- Reliabiilty (1)
- Reliable characterization (1)
- Renewable Energy (1)
- Renewable energy (1)
- Repelling surface coatings (1)
- Reporter (1)
- Representative morphology modeling (1)
- Research Data Management (1)
- Resins (1)
- Resonance (1)
- Reverse microemulsion (1)
- Ridis amorphous fraction (1)
- Ripples (1)
- Risk Governance (1)
- Risk asessment (1)
- Risstrajektorie (1)
- Robocasting (1)
- Robotic synthesis (1)
- Robotic-supported synthesis (1)
- Roughness (1)
- Round Robin (1)
- Rreference material (1)
- Röntgenrefraktion (1)
- SARS-CoV 2 (1)
- SARS-CoV2 inhibitor (1)
- SBA-16 (1)
- SDLs (1)
- SKPM (1)
- SMPS (1)
- SRA (1)
- SSB (1)
- SSbD (1)
- STEM-in-SEM (1)
- STEM-in-SEM (TSEM) (1)
- STL file input (1)
- SWIR photoluminescence (1)
- Sabatier (1)
- Saccharide sensing (1)
- Safe by design (1)
- Safe-by-design (1)
- Safer by design (1)
- Sall-angle scattering (1)
- Sample peparation (1)
- Saphir (1)
- Saponite (1)
- Scannig probe microscope (1)
- Scanning Auger Spectroscopy (1)
- Scanning Electron Microscopy (1)
- Scanning Kelvin Probe Force Microscopy (SKPFM) (1)
- Scanning Probe Microscopy (1)
- Scanning Probe methods (1)
- Scanning micro-X-ray fluorescence (1)
- Scanning probe measurements (1)
- Scanning probe microscopy (1)
- Scanning transmission X-ray microscopy (STXM) (1)
- Scattering pattern (1)
- Scattering pattern simulation (1)
- Schlangenbohne (1)
- Schmiermittel (1)
- SchwarzP cells (1)
- Scientific misconduct (1)
- Screening (1)
- Screening method (1)
- Scribal corrections (1)
- Second-generation high temperature superconductor technology (1)
- Secondary Ion Mass Spectrometry (1)
- Self-degrading (1)
- Self-driving Labs (1)
- Semantic Interoperability (1)
- Semiconductor materials (1)
- Semiconductor nanocrystals (1)
- Semiconductur (1)
- Sensing; temperature (1)
- Sensitization (1)
- Sensor Materials (1)
- Sensor molecules (1)
- Separation membranes (1)
- Sequential Learning (1)
- Shape-controlled (1)
- Shape-memory alloys (1)
- Shortwave infrared (1)
- Si-Ge (1)
- SiO2 Nanoparticle (1)
- Sialic acid (1)
- Silanisation (1)
- Silica Nanoparticles (1)
- Silica coating (1)
- Silica particles (1)
- Silica- and Polystyrene Particles (1)
- Silica- and polystyrene particles (1)
- Silicon nanoparticles (1)
- Silver indium sulfide (1)
- Simulations (1)
- Single asperity (1)
- Single asperity contact (1)
- Single cell-ICP-ToF-MS (1)
- Single enhancement (1)
- Single molecule (1)
- Single particle spectroscopy (1)
- Single particle-ICP-ToF-MS (1)
- Single-dot spectroscopy (1)
- Single-particle measurements (1)
- Singlet oxygen (1)
- Size and size distribution (1)
- Size measurement (1)
- Size measurements (1)
- Slicers (1)
- Sliding (1)
- Slurry (1)
- Small angle x-ray scattering (1)
- Small-Angle X-ray Scattering (1)
- Small-angle X-ray Scattering (1)
- Small-angle x-ray scattering (1)
- Small-area XPS (1)
- Smartphone readout device (1)
- Software UNIFIT 2022 (1)
- Sol-gel (1)
- Sol-gel synthesis (1)
- Solar cell (1)
- Solar cells (1)
- Solarpur (1)
- Solid state (1)
- Solid-binding Peptides (1)
- Sonochemical synthesis (1)
- SpICP-MS (1)
- Speciation analysis (1)
- Specific Surface Area (BET) (1)
- Specific heat spectroscopy (1)
- Specific surface (1)
- Spectroscopy / Instrumentation (1)
- Spectroscopy / Theory (1)
- Spektroskopie (1)
- Spezifische Oberfläche (1)
- Spin (1)
- Stabilization (1)
- Standard Operation Procedures (1)
- Standard operation procedures (1)
- Standardarbeitsanweisung (1)
- Standardarbeitsanweisungen (1)
- Standardized check (1)
- Stepwise growth (1)
- Stochastic Landau Lifshitz equation (1)
- Strain measurement (1)
- Strategic Research Agenda (SRA), (1)
- Strontium titanate (1)
- Structural characterisation (1)
- Structural color (1)
- Structural precision (1)
- Structure activity relationships (1)
- Structure–property correlation (1)
- Structure–property relationship (1)
- Sulfated materials (1)
- Superconductivity (1)
- Superelasticity (1)
- Superparamagnetism (1)
- Surface Activation (1)
- Surface Analysis Working Group (1)
- Surface Analytics (1)
- Surface Chemical Transformation (1)
- Surface Chemistry (1)
- Surface Modification (1)
- Surface characterization (1)
- Surface chemisttry (1)
- Surface coating (1)
- Surface engineering (1)
- Surface functional group quantification (1)
- Surface groups (1)
- Surface modified nano- and microparticles (1)
- Surface morphology and chemistry (1)
- Surface plasmon polaritons (1)
- Surface plasmon resonance (1)
- Surface properties (1)
- Surface regeneration (1)
- Surface superconductivity (1)
- Surface-induced Melting (1)
- Surface-initated grafting (1)
- Surfaces, Coatings and Films (1)
- Sustainability and the Environment (1)
- Sustainable-by-Design (1)
- Suzuki-Miyaura coupling (1)
- Swarming (1)
- Switch (1)
- Synergistic effects (1)
- Synergy (1)
- Synthesis library (1)
- Systems architecture (1)
- TGA-MS (1)
- TMDCs (1)
- TOPAS-nBio (1)
- TRL (1)
- TSEM (1)
- Tafel Plot (1)
- Tag (1)
- Targeted nanoparticle (1)
- Temparatur modulated Flash DSC (1)
- Temperature effects (1)
- Temperature modulated DSC (1)
- Temperature modulated differential scanning calorimetry (1)
- Terminal functional groups (1)
- Termites (1)
- Test artifact (1)
- Test structure (1)
- Testguideline (1)
- Theoretical modelling (1)
- Theranostics (1)
- Therapeutic antibodies (1)
- Therapy (1)
- Thermal annealing (1)
- Thermal coupling energy level (1)
- Thermal desorption mass spectrometry (1)
- Thermally coupled levels (1)
- Thermogravimetry (1)
- Thermoset (1)
- Thermoset composition (1)
- Thermosets (1)
- Thetaevolve (1)
- Thick shells (1)
- Thickness measurements (1)
- Thin Layers (1)
- Thin film (1)
- Thin film analysis (1)
- Thin film systems (1)
- Thin magnetic films (1)
- Thin mesoporous films (1)
- Thin solid layers (1)
- Thiol-ene click chemistry (1)
- Thiols (1)
- Threshold (1)
- Thumor therapy (1)
- Ti oxide (1)
- Ti-6Al-4V alloy (1)
- Ti6Al4V alloys (1)
- TiO2 D540 nanoparticles (1)
- TiO2 PVP (1)
- TiO2 nanoparticle (1)
- TiO2 nanoparticles (1)
- Time of Flight - Secondary ion mass spectrometry (1)
- Time-of-Flight Secondary Ion Mass Spectrometry (1)
- Time-of-flight secondary ion mass spectrometry (1)
- Time-offlight secondary ion mass spectrometry (ToF-SIMS) (1)
- Time-resolved analysis (1)
- Time-resolved coherent scattering (1)
- Titanium (1)
- Titanium alloys (1)
- Titanium oxide (1)
- ToF SIMS (1)
- Tools (1)
- Tools to combat scientific misconduct (1)
- Topas-nbio (1)
- TopasMC (1)
- Torah scrolls (1)
- Total scattering (1)
- Toxicity (1)
- Traceability derivation (1)
- Traceable nanoparticle size measurements; (1)
- Transition electron microscopy (1)
- Transition metal dichalcogenide (1)
- Transmission Electron Microscopy (1)
- Transmission electron microsocpy (1)
- Transmission function IERF (1)
- Transparent conductive Oxides (1)
- Transport limitations (1)
- Trastuzumab (1)
- Trends (1)
- Triazine (1)
- Triggered (1)
- Trinkwasser (1)
- Triplet-triplet annihilation (1)
- Tungsten (1)
- Twin orientation relationship (1)
- Two photon polymerization (1)
- Two-Photon Polymerization (1)
- Two-dimensional hexagonal boron nitride(h-BN) (1)
- Two-photon adsorption (1)
- Two-photon polymerisatio (1)
- Two-photon-polymerization (1)
- Type-I pyrethroids (1)
- UV Weathering (1)
- UV-curing (1)
- UiO (1)
- Ultrakurzpuls-Laser (1)
- Ultrakurzpuls-Laserbearbeitung (1)
- Ultraschall (1)
- Ultraschallunterstütztes Fräsen (1)
- Ultrashort lasers (1)
- Uncertainty budget (1)
- UpConversion (1)
- Upconverion (1)
- Upconversion luminescence (1)
- Upconverstion (1)
- Upconverting nanoparticles (1)
- Upscaling (1)
- VMAAS (1)
- VRFB (1)
- Van der Waals forces (1)
- Vanadium speciation (1)
- Variable excitation (1)
- Vernetzung (1)
- Verschleißreduktion (1)
- Video (1)
- Vigna unguiculata (1)
- Virucidality (1)
- Viskosität (1)
- Vitriolic iron-gall inks (1)
- Volatiles from thermosets (1)
- Volcano plot (1)
- Vulcanization (1)
- Wastewater (1)
- Water (1)
- Water analysis (1)
- Water dispersibility (1)
- Water electrolysis (1)
- Water filtration (1)
- Water management (1)
- Waxs (1)
- Wear particles (1)
- Werkstoffe (1)
- Wet dispersion (1)
- White light interferometric microscopy (1)
- White light interferometry microscopy (1)
- White-light Interference Microscopy (1)
- White-rot fungi (1)
- Wide-bandgap semiconductors (1)
- Wide-range (1)
- Wirksumme (1)
- Wood protection (1)
- Workflow (1)
- Workflows (1)
- X-Ray Spectroscopy (1)
- X-Ray analysis (1)
- X-ray Photoelectron Spectroscopy (1)
- X-ray Absorption Spectroscopy (1)
- X-ray Fluorescence (1)
- X-ray Photoelectron Spectroscopy (XPS) (1)
- X-ray generation (1)
- X-ray instrumentation (1)
- X-ray microscopy (1)
- X-ray microspectroscopy (1)
- X-ray photoelectron spectroscopy (XPS) (1)
- X-ray production efficiency (1)
- X-ray spectrometer (1)
- X-rays (1)
- XCT (1)
- XPS spctroscopy (1)
- XRM (1)
- XUV scattering (1)
- Yb(III) complex (1)
- Young´s modulus (1)
- Yttria stabilized zirconia (1)
- Yttria-stabilized zirconia (1)
- ZIF-8 (1)
- Zeolitic Imidazolate Frameworks (1)
- Zero wear (1)
- Zinc phosphate (1)
- Zirconium (1)
- ZnO (1)
- ZnO nanoparticles (1)
- ZnSe (1)
- ZrO2 nanoparticles (1)
- [MMIM]+[DMP]− (1)
- abasic side (1)
- aggregation-induced dual emission (AIDE) (1)
- analytical service (1)
- anion-exchange (1)
- antibody (1)
- attraktive Wechelwirkung (1)
- automation (1)
- bacteria (1)
- bacteria detection (1)
- base loss (1)
- bended arrow of time (1)
- bioactive (1)
- bioimaging (1)
- biomaterials (1)
- bone (1)
- clustered nanoparticles (1)
- dispersion (1)
- dsDNA (1)
- electron microscopy (1)
- flow cytometry (1)
- fluorescence microscopy (1)
- gamma ray (1)
- graphene related 2D materials (1)
- immunoseparation (1)
- instrument utilization (1)
- laboratory automation (1)
- laboratory management (1)
- lifetime (1)
- magnetic nanoparticle (1)
- metadata collection (1)
- method (1)
- nm films (1)
- organic dyes (1)
- particle (1)
- particle size determination (1)
- quality assurcance (1)
- quantum dot (1)
- quantum yield (1)
- radiolysis (1)
- research efficiency (1)
- sample preparation (1)
- screening tes (1)
- shape control (1)
- single cell-ICP-ToF-MS (1)
- single particle-ICP-ToF-MS (1)
- stl code (1)
- temeprature dependent exchange length (1)
- time-temperature equivalent formulation (1)
- time-temperature superposition principle (1)
- total scattering (1)
- transmission mode (1)
- wrapping (1)
- µ-XRF (1)
- Äquivalenzdurchmesser (1)
Organisationseinheit der BAM
- 6 Materialchemie (666)
- 6.1 Oberflächen- und Dünnschichtanalyse (348)
- 1 Analytische Chemie; Referenzmaterialien (186)
- 1.2 Biophotonik (161)
- 6.6 Physik und chemische Analytik der Polymere (136)
- 6.5 Synthese und Streuverfahren nanostrukturierter Materialien (131)
- 6.2 Material- und Oberflächentechnologien (90)
- 5 Werkstofftechnik (62)
- 4 Material und Umwelt (46)
- 5.4 Multimateriale Fertigungsprozesse (33)
Paper des Monats
- ja (16)
Engineered and tailored nanomaterials (NM) are of great interest in the life and material sciences, as they can be used, e.g., as drug carriers, barcodes, fluorescent sensors, and multimodal labels in bioanalytical assays and imaging applications. Their performance and safety depend not only on their particle size, size distribution, and morphology, but also on their surface chemistry, i.e., the total number of surface functional groups (FG) and the number of FG accessible for subsequent functionalization with ligands or biomolecules, which in turn determines surface charge, colloidal stability, biocompatibility, and toxicity. It also underlines the importance of validated analytical methods that provide accurate information on these application-relevant physicochemical properties with a known uncertainty. In the case of FG quantification, this calls for robust, fast, inexpensive, and reliable methods which allow for the characterization of a broad variety of NM differing in size, chemical composition, and optical properties.
Methods
Aiming at the development of simple, versatile, and multimodal tools for the quantification of bioanalytically relevant FG such as amine, carboxy, thiol, and aldehyde functionalities, we investigated and compared various analytical methods commonly used for FG quantification. This includes electrochemical titration methods, dye-based optical assays, and other instrumental analytical techniques such as nuclear magnetic resonance (NMR), mass spectrometry (MS), and thermal analysis methods.
Results
Here, we will present examples for different types of NMs and FGs including results from a currently running interlaboratory comparison (ILC) with the National Research Council of Canada (NRC) to pave the road for method standardization.
Innovative aspects
• Surface analysis
• Performance and safety of nanomaterials
• Standardization
Engineered nanomaterials (NM) with their large surface-to-volume ratios and their for some materials observed size-dependent functional properties are of increasing relevance for current and future developments in various fields such as medical and pharmaceutical industry, computing and electronics or food and consumer products. The performance and safety of NM are determined by the sum of their intrinsic physicochemical properties. Especially, the particle surface chemistry, which is largely controlled by the chemical nature and density of functional groups (FG) and ligands, is an important key driver for NM performance, stability, and processibility as well as the interaction of NM with the environment. Thus, methods for FG quantification can foster the sustainable development of functional and safe(r) NM.
Aiming at the development of simple, versatile, and multimodal tools for the quantification of many bioanalytically relevant FG and ligands, we investigated and compared various analytical methods commonly used for FG quantification. This includes electrochemical titration methods, dye-based optical assays, and other instrumental analytical techniques such as nuclear magnetic resonance and thermal analysis methods.
The potential of our multimodal approach for FG quantification was demonstrated for commercial and custom-made polymeric and silica particles of varying FG, used as optical pH sensors. In the future, our strategy can contribute to establish multi-method characterization strategies to provide a more detailed picture of the structure-properties relationship.
In recent years, the use of functionalized micro- and nanomaterials has increased rapidly for a wide range of applications in the life and material sciences, due to their unique properties in combination with their high surface-to-volume ratio and stability. For instance, functionalized micro- and nanomaterials, that are labeled or stained with a multitude of sensor dyes can be used for monitoring, and quantification of neutral and ionic analytes. These materials have several advantages as compared to conventional molecular probes like enhanced brightness, ease of designing ratiometric systems by combining analyte-sensitive and inert reference dyes, and increased photostability. Moreover, stained nanoparticles can enable the use of hydrophobic dyes in aqueous environments.
Versatile templates and carriers for the fabrication of nanosensors by staining and/or labeling with different fluorophores and sensor molecules are biocompatible silica and polymeric particles, because they can be synthesized in large scales at low costs with different surface chemistries.
Here we present our work on multicolored sensors for the measurement of pH, oxygen and saccharides utilizing commercially available or in-house synthesized silica and polymeric particles.
Nowadays amorphous silica nanoparticles (SiO2-NP) are one of the most abundant engineered nanomaterials, that are highly stable and can be easily produced on a large scale at low cost. Surface functionalized SiO2-NP are of great interest in the life and material sciences, as they can be used e.g. as
drug carriers, fluorescent sensors, and multimodal labels in bioanalytical assays and imaging applications. Their performance in such applications depends not only on particle size, size distribution, and morphology, but also on surface chemistry, i.e. the total number of surface functional groups (FG)
and the number of FG accessible for subsequent functionalization with ligands or biomolecules, which in turn determines surface charge, colloidal stability, biocompatibility, and toxicity. Aiming at the development of simple, versatile, and multimodal tools for the quantification of many bioanalytically relevant FG and ligands, we investigated and compared various analytical methods commonly used for FG quantification. This includes electrochemical titration methods, dye-based optical assays, and other instrumental analytical techniques such as nuclear magnetic resonance and thermal analysis methods.
The potential of our multimodal approach for FG quantification was demonstrated for commercial and custom-made silica particles of varying FG, showing not only an influence of the synthesis methods on the number of FG but also on the performance. In the future, our strategy can contribute to establish multi-method characterization strategies to provide a more detailed picture of the structure-properties relationship.
In the focus of division Biophotonics are the design, preparation, analytical and spectroscopic characterization, and application of molecular and nanoscale
functional materials, particularly materials with a photoluminescence in the visible, near infrared (NIR) and short-wave infrared (SWIR). This includes optical reporters for bioimaging and sensing, security and authentication barcodes, and materials for solid state lighting, energy conversion, and photovoltaics. For the identification of optimum particle structures quantitative spectroscopic studies are performed under application-relevant conditions, focusing on the key performance parameter photoluminescence quantum yield. In addition, simple, cost-efficient, and standardizable strategies for quantifying functional groups on the surface of nano- and microparticles are developed, here with a focus on optical assays and electrochemical titration methods, cross-validated by more advanced methods such as quantitative NMR. In addition, reference materials and reference products are developed for optical methods, particularly luminescence techniques, and for analytical methods utilized for the characterization of nanomaterials.
There is an urgent demand for reliable data on microplastic analysis, particularly on its physico-chemical properties as well as validated methodology to obtain such data. Through interlaboratory comparisons (ILCs) it becomes possible to assess accuracy and precision of methods by involving many laboratories around the world. At BAM, my tasks focused around organisation of an ILC on physico-chemical characterisation of microplastic detection methods under the international pre-standardisation platform VAMAS (www.vamas.org/twa45/) as Project 2 “Development of standardized methodologies for characterisation of microplastics with microscopy and spectroscopy methods” under the Technical Working Area TWA 45 “Micro and Nano Plastics in the Environment”.
With a proud number of 84 participants this ILC is able to provide superior statistical results. Thermoanalytical (Py-GC/MS and TED-GC/MS) and vibrational (µ-IR and µ-Raman) methods were asked for identification and quantification of microplastic test samples according to mass or particle number. Preliminary results indicate which methods show a higher accuracy and precision and reveal some sample preparation ideas which work best for microplastics characterisation. At the end of the ILC an overall plausibility of the results will be assessed.
Synthesis of Li ion battery materials via ball milling has been a huge area of growth, leading to new high-capacity electrode materials, such as a number of promising disordered rocksalt (DRS) phases. In prior work, it was generally assumed that the synthesis was facilitated simply by local heating effects during the milling process. In this work, we show that ball milling Li2MoO4 leads to a phase transformation to the high pressure spinel polymorph and we report electrochemical data for this phase. This observation of the formation of a high pressure polymorph shows that local heating effects alone cannot explain the phase transformation observed (phenakite to spinel) and so indicates the importance of other effects. In particular, we propose that when the milling balls collide with the material, the resulting shockwaves exert a localised pressure effect, in addition to local heating. To provide further support for this, we additionally report ball milling results for a number of case studies (Li2MnO3, Li2SnO3, Nb2O5) which reinforces the conclusion that local heating alone cannot explain the phase transformations observed. The work presented thus provides greater fundamental understanding of milling as a synthetic pathway and suggests potential strategies to prepare such samples without milling (e.g., doping to create internal chemical pressure). In addition, we suggest that further research is needed into the effect of the use of milling as a route to smaller particles, since we believe that such milling may also be affecting the surface structure of the particles through the influence of the shockwaves generated.
A series of aroyl-S,N-ketene acetal based bichromophores is readily synthesized by Buchwald-Hartwig amination and Ullmann reaction in moderate to good yields. The aminated aroyl-S,N-ketene acetals are emissive in the solid state and in the aggregate, but not in solution, thus, they are AIEgens (aggregation induced emission chromogens). Aggregation is induced by fractional alternation of the solvent mixture, here by increasing the water fraction of ethanol/water mixtures. For most derivatives, the emission upon induced aggregation stems solely from the aroyl-S,N-ketene acetal chromophore, regardless whether excitation occurs at the absorption maximum of the triarylamine or the aroyl-S,N-ketene acetal. Therefore, a pronounced energy transfer from the triarylamine donor to the aroyl-S,N-ketene acetal acceptor can be inferred. The color of the emission can be controlled by choosing the para-aroyl substituent. A partial energy transfer could also be observed for some bichromophores, leading to aggregation-induced dual emission (AIDE). In addition, four examples of aminated diaroyl-S,N-ketene acetals were added to the compound library. The electron-withdrawing properties of the additional aroyl group provide a bathochromic shift of the emission band of the aroyl-S,N-ketene acetal. These bichromophores also show AIDE and in one case even aggregation-induced white light emission as a result of additive color mixing.
Liaison of ISO/TC 202 Microbeam Analysis with VAMAS/TWA 37 Quantitative Microstructural Analysis
(2023)
The progress in activities on Microbeam Analysis under VAMAS/TWA 37 is reviewed. Particularly the liaison with the new projects within the ISO technical committee TC 202 is presented and discussed with respect to the identification and launching corresponding VAMAS projects. The ongoing project "FIB sample processing for TEM" is presented in detail.
Titanium and its alloys are known to allow the straightforward laser-based manufacturing of ordered surface nanostructures, so-called high spatial frequency laser-induced periodic surface structures (HSFL). These structures exhibit sub-100 nm spatial periods – far below the optical diffraction limit. The resulting surface functionalities are usually enabled by both, topographic and chemical alterations of the nanostructured surfaces. For exploring these effects, multi-method characterizations were performed here for HSFL processed on Ti–6Al–4V alloy upon irradiation with near-infrared ps-laser pulses (1030 nm, ≈1 ps pulse duration, 1–400 kHz) under different laser scan processing conditions, i.e., by systematically varying the pulse repetition frequency and the number of laser irradiation passes. The sample characterization involved morphological and topographical investigations by scanning electron microscopy (SEM), atomic force microscopy (AFM), tactile stylus profilometry, as well as near-surface chemical analyses hard X-ray photoelectron spectroscopy (HAXPES) and depth-profiling time-of-flight secondary ion mass spectrometry (ToF-SIMS). This provides a quantification of the laser ablation depth, the geometrical HSFL characteristics and enables new insights into the depth extent and the nature of the non-ablative laser-induced near-surface oxidation accompanying these nanostructures. This allows to answer the questions how the processing of HSFL can be industrially scaled up, and whether the latter is limited by heat-accumulation effects.
Although the use of noble metal catalysts can increase the efficiency of hydrogen evolution reaction, the process is still limited by the characteristics of the metal-hydrogen (M−H) bond, which can be too strong or too weak, depending on the metal employed. Studies revealed that the hydrogen affinity for the metal surface (i.e. H absorption/desorption) is regulated also by the potential at the metal nanoparticles. Through controlled periodic illumination (CPI) of a series of metal/TiO2 suspensions, here we demonstrated that an increase of the HER efficiency is possible for those photodeposited metals which have a Tafel slope below 125 mV. Two possible explanations are here reported, in both of them the M−H interaction and the metal covering level play a prominent role, which also depend on the prevailing HER mechanism (Volmer-Heyrovsky or Volmer-Tafel).
Liaison activities within ISO/TC 202 'Microbeam Analysis' which are relevant to ISO/TC 229 'Nanotechnologies' are reported acoording to the structure defined by ISO/TC229 Nanotechnologies Liaisons Coordination Group (NLCG): new standards/documents, coordination issues, and further detailed specific information, e.g. publications, events, comments.
Laser-induced periodic surface structures (LIPSS) represent a unique route for functionalizing materials through the fabrication of surface nanostructures. Commercial AISI 316L stainless steel (SS316L) surfaces are laser treated by ultraviolet 300 ps laser pulses in a laser line scanning (LLS) approach. Processing parameters are optimized (pulse energy of 2.08 µJ, pulse repetition frequency of 300 kHz, and suitable laser scan and sample displacement rates) for the generation of low spatial frequency LIPSS over a large 25 × 25 mm2 area. Different angles of incidence of the laser radiation (0°, 30°, and 45°) and different linear laser beam polarizations (s and p) produce a plethora of rippled surface morphologies at distinct grains. Scanning electron microscopy and 2D Fourier transforms, together with calculations of the optical energy deposited at the treated surfaces using Sipe's first-principles electromagnetic scattering theory, are used to study and analyze in detail these surface morphologies. Combined with electron backscattering diffraction, analyses allow associating site-selectively various laser-induced-surface morphologies with the underlying crystalline grain orientation. Resulting grain orientation maps reveal a strong impact of the grain crystallographic orientation on LIPSS formation and point toward possible strategies, like multi-step processes, for improving the manufacturing of LIPSS and their areal coverage of polycrystalline technical materials.
Inspired by the chemistry of mussel adhesive proteins, polydopamine (PDA has been shown as one of the most versatile platforms for altering the properties and incorporating new functionalities to nearby any material surface despite its nature. Rich chemistry of PDA enables broad variety of surface modification and diverse secondary reactions that makes it extremely interesting for a wide range of application including biomedical field, e.g., drug delivery, adhesives, cell adhesion, biosensing. Despite high potential of polydopamine, the lack of deposition control and precision in existed methods limits their applications in microdevices and miniaturized functional systems like, for example, MEMS, microfluidic and sensorics.
Herein, we demonstrate a novel maskless approach for surface micropatterning with polydopamine based on Multiphoton Lithography that overcomes present limitations. Neither strong oxidants, metal ions nor adjustment of pH to alkaline is required by this technique. The spatial resolution down to 0.8 µm has been achieved which is at least an order of magnitude smaller than shown by other existed methods. We are able to control the morphology and thickness of the micropattern by altering fabrication parameters allowing structure gradient.
Apart from the glass substrate, we achieved PDA patterning at surfaces of different nature such as polychlorotrifluoroethylene, polydimethylsiloxane, polyethylene terephthalate, silicon wafers, and fluorinated glass coverslips. Post-modification of polydopamine micropatterns with protein enzyme like trypsin is demonstrated to highlight its sensing potential.
Presented in this work microfabrication technique empowers advanced applications of mussel-inspired materials in single-molecule bioassays, sensors and other complex microdevices.
Text Multiphoton lithography (MPL) has recently attracted significant research interest as a versatile tool capable of producing 2D and 3D micro- and nanoscopic features with high spatial resolution. The integrity of MPL microstructures, or their ability to respond to external stimuli, is of critical importance. However, achieving the desired properties of fabricated microcomponents for a specific application remains a challenge.
In this work, we present new MPL materials based on epoxy-acrylate interpenetrating networks (IPNs). We aim at 3D microstructures, whose properties can be easily tuned by varying the ratio of the IPN components and fabrication parameters (Figure 1). The resulting library of 3D microstructures was investigated for their thermal and mechanical properties using highly-sensitive space-resolved methods. Flash scanning calorimetry revealed the influence of both, IPN composition and fabrication parameters, on glass transition temperature and material fragility. AFM force-distance curve and intermodulation methods were used to characterize the mechanical properties with a lateral resolution of 1 micron and 4 nm, respectively. The deformation, stiffness and elastic behavior are discussed in detail in relation to the morphology. Moreover, we found that some 3D IPN microstructures exhibit fully elastic behavior. Our funding encourages the further development of IPN systems as versatile and easily tunable MPL materials.
AbstractThis work addresses the critical need for multifunctional materials and substrate‐independent high‐precision surface modification techniques that are essential for advancing microdevices and sensing elements. To overcome existing limitations, the versatility of mussel‐inspired materials (MIMs) is combined with state‐of‐the‐art multiphoton direct laser writing (DLW) microfabrication. In this way, 2D and 3D MIM microstructures of complex designs are demonstrated with sub‐micron to micron resolution and extensive post‐functionalization capabilities. This study includes polydopamine (PDA), mussel‐inspired linear, and dendritic polyglycerols (MI‐lPG and MI‐dPG), allowing their direct microstructure on the substrate of choice with the option to tailor the patterned topography and morphology in a controllable manner. The functionality potential of MIMs is demonstrated by successfully immobilizing and detecting single‐stranded DNA on MIM micropattern and nanoarray surfaces. In addition, easy modification of MIM microstructure with silver nanoparticles without the need of any reducing agent is shown. The methodology developed here enables the integration of MIMs in advanced applications where precise surface functionalization is essential.
Particle size determination of a commercially available CeO2 nano powder - SOPs and reference data
(2023)
Compilation of detailed SOPs for characterization of a commercially available CeO2 nano powder including
- suspension preparation (indirect and direct sonication),
- particle size determination (Dynamic Light Scattering DLS and Centrifugal Liquid Sedimentation CLS) with reference data, respectively.
For sample preparation and analysis by Scanning Electron Microscopy (SEM) of this powder see related works (submitted, coming soon).
Bacterial biofilms pose serious problems in medical and industrial settings. One of the major societal challenges lies in the increasing resistance of bacteria against biocides used in antimicrobial treatments, e.g., via overabundant use in medicine, industry, and agriculture or cleaning and disinfection in private households. Hence, new efficient bacteria-repellent strategies avoiding the use of biocides are strongly desired. One promising route to achieve bacteria-repellent surfaces lies in the contactless and aseptic large-area laser-processing of technical surfaces. Tailored surface textures, enabled by different laser-processing strategies that result in topographic scales ranging from nanometers to micrometers may provide a solution to this challenge. This article presents a current state-of-the-art review of laser-surface subtractive texturing approaches for controlling the biofilm formation for different bacterial strains and in different environments. Based on specific properties of bacteria and laser-processed surfaces, the challenges of anti-microbial surface designs are discussed, and future directions will be outlined.
Noble metal-free nanoparticles (NPs) based on multi-principal element alloys (MPEAs) were synthesized using a one-step pulsed laser ablation in liquids (PLALs) method for the electrochemical reduction of CO2. Laser ablation was performed in pure water or poly-(diallyldimethylammonium chloride) (PDADMAC)-containing an aqueous solution of Al8Cr17Co17Cu8Fe17Ni33 MPEA targets. Transmission electron microscopy (TEM) measurements combined with energy dispersive X-ray (EDX) mapping were used to characterize the structure and composition of the laser-generated MPEA nanoparticles (MPEA-NPs). These results confirmed the presence of a characteristic elemental distribution of a core-shell phase structure as the predominant NP species. The electrocatalytic performance of the laser-generated MPEA-NPs was characterized by linear sweep voltammetry (LSV) demonstrating an enhanced electrocatalytic CO2 activity for PDADMAC-stabilized NPs. The findings of these investigations indicate that MPEAs have great potential to replace conventional, expensive noble metal electrocatalysts.
AbstractWe report on gold clusters with around 62 gold atoms and a diameter of 1.15±0.10 nm. Dispersions of the clusters are long‐term stable for two years at ambient conditions. The synthesis was performed by mixing tetrachloroauric acid (HAuCl4 ⋅ 3 H2O) with the ionic liquid 1‐ethyl‐3‐methylimidazolium dicyanamide ([Emim][DCA]) at temperatures of 20 to 80 °C. Characterization was performed with small‐angle X‐ray scattering (SAXS), UV‐Vis spectroscopy, and MALDI‐TOF mass spectrometry. A three‐stage model is proposed for the formation of the clusters, in which cluster growth from gold nuclei takes place according to the Lifshitz‐Slyozov‐Wagner (LSW) model followed by oriented attachment to form colloidal stable clusters.
Gold-based nanoparticles below 2 nm in size are promising as luminescent probes for in vivo bioimaging, owing to their brightness and rapid renal clearance. However, their use as contrast agents in the near-infrared II (NIR-II, 1000–1700 nm) range remains challenging due to their low photoluminescence (PL) quantum yield. To address this, PL enhancement can be achieved by either rigidifying the ligand-shell structure or increasing the size of the ligand shell. In this study, we synthesized ultra-small gold nanoparticles stabilized by co-ligands, namely monothiol and short dithiol molecules. By precisely controlling the amount of reducing agent used during particle preparation, we successfully modulated the physicochemical properties of the co-ligand shell, including its size, composition, and structure. Consequently, we achieved a remarkable 60-fold increase in the absorption cross-section at 990 nm while maintaining the small size of the 1.5-nm metal core. The analytical and optical characterization of our thiol-capped gold nanoparticles indicates that the ligand shell size is governed by the quantity of the reducing agent, which, in turn, impacts the balance between radiative and non-radiative processes, thereby influencing the PL quantum yield.
Superparamagnetic hybrid polystyrene-core silica-shell beads have emerged as promising alternatives to traditional in flow cytometry-based competitive antibody assays [1]. These materials consist of a polystyrene core and a silica shell, in which magnetic nanoparticles are embedded, facilitating the handling and retention in tests. The outer silica surface allows for easy modification through silane chemistry, allowing the attachment of antibodies, or other molecules of interest. Ochratoxin A (OTA), a mycotoxin that can be found in grain products, coffee, cacao, or grapes, was chosen as the main target analyte to detect [2]. In this study, previously in house produced anti-OTA antibodies [3] were attached to the surface of the particles and the whole system was used as detection entity. In a first approach, the system was used for the development of a competitive cytometry assay using an OTA-fluorescein (OTA-F) adduct as competitor and marker. In this assay the fluorescence emitted by the OTA-F competitor on the surface of the particle was detected at a wavelength of 518 nm using a 533/30.H filter and was correlated to the forward scatter (FSC) to distinguish it from the excess of competitor still in solution. Under optimised conditions, the final assay showed a limit of detection of 0.03 nM. In a second approach, a simplified ready-to-inject fluidic system was built based on a laser (488 nm) and a photomultiplier detector to measure the signal of competitor still in solution. The competition step was carried out in a vial and the whole mixture was injected into the fluidic system. To avoid signal scattering, the particles were separated in-line using a magnet and only the OTA-F competitor still in solution was detected, reaching a limit of detection of 1.2 nM. With the aim to reduce user manipulation, the final assay is still under development for in-line incubation during the competitive step.
The progress of the VAMAS interlaboratory comparison Project P13 "Lateral size of graphene oxide flakes by SEM" within the Technical Working Area 41 "Graphene and Related 2D Materials" is presented. The challenges at sample preparation on substrates for accurate measurement and image analysis as well as two different analysis approaches, containing exact guidance how to measure the main descriptors for the lateral size measurement of the imaged graphene oxide flakes with Scanning Electron Microscopy are highlighted. The implementation of the results into the corresponding ISO technical specification AWI/TS 23879 is also discussed and planned, in relation with the AFM part.
Tailor-made nanoparticles are of increasing interest in e.g. catalysis, as sensor materials, analytical assays, or can have superior photophysical properties. A major issue concerning the preparation of high-quality and functional nanoparticles is a good control of particle size, shape, polydispersity, and composition.
Small Angle X-ray Scattering (SAXS) is a non-destructive method for the analysis of nanostructures in a wide variety of materials. This method allows determining averaged structural parameters on a length scale from just above atomic sizes up to several 100 nanometers such as sizes, size distributions, volume fractions, and inner surface sizes. Moreover, anomalous Small Angle X-ray Scattering (ASAXS) exploits the anomalous dispersion of the scattering amplitudes near the X-ray absorption edges of the elements contained in the sample. These element sensitive contrast variations can be used to analyse average composition fluctuations on the nm scale. Two kinds of nanoparticles are chosen here to elaborate the advantages of ASAXS in the analysis of complex materials.
A facile and efficient methodology is developed for the thermal synthesis of size-tunable, stable, and uniform bimetallic NiCu core–shell nanoparticles (NPs) for various application in catalysis. Their diameter can be tuned in a range from 6 nm to 30 nm and the Ni:Cu ratio is adjustable in a wide range from 1:1 to 30:1. The NPs are structurally characterized by a method combination of transmission electron microscopy, anomalous small-angle X-ray scattering (ASAXS), X-ray absorption fine structure, and X-ray photoelectron spectroscopy. Here, we focus on the ASAXS method and its ability to analyses nanostructure parts and their compositions at once. As a result, a NiCu alloyed core surrounded by a Ni enriched shell and an outer NiO shell was found.
Semiconductor nanocrystals (quantum dots, QDs) are well known for their superior photophysical properties and enabled advancements in several key technologies of the 21st century and numerous technological applications like in photovoltaics, LED displays, photocatalysis, and biosensing. To achieve high photoluminescence quantum yields (PLQY) and enhanced photostability the QD core needs to be passivated by a second semiconductor, which possess a larger band gap to confine the charges within the QD core. An important parameter is thereby the lattice mismatch between the core and shell. To avoid strong lattice strain, which would alter the photophysical properties, an intermediary shell can be used as a lattice adapter between the core and the outer shell leading to core/shell/shell systems. These systems have shown to possess high PLQYs combined with a strong long-term stability and can be found in modern QLED displays. ASAXS was used here to better understand the core/shell/shell structure of InP/ZnSe/ZnS QDs to enable a correlation between their structural and photophysical properties.
Al3(Sc,Zr,Ti) nanoparticles with an ideal twin-type orientation relationship to Al host matrix were found in cold-rolled and subsequently annealed Al-based alloy. Atomic-scale investigations using high-resolution scanning transmission electron microscopy identified particles that form prominent coherent (111) twin-type interfaces along their longer facets and semi-coherent twin interfaces on their shorter facets. Ab-initio calculations showed that a coherent Al/Al3Sc twin-like phase boundary corresponds to a local energy minimum. A model is proposed explaining the formation of the twin orientation relationship of an Al3Sc nanoparticle with the Al host matrix.
The presentation shows the results of the mini-interlaboratory comparison focused on the measurement of the morphology of graphene oxide flakes using scanning electron microscopy. In this work, a route for the sample preparation, SEM measurement and image analysis is proposed. The results of the image analysis, performed on 200+ flakes per sample, are presented by comparing the distributions of the size and shape descriptors calculated according to two different approaches. The influences of a different SEM measurement operator, analysis approach and analysis operator on the final size and shape distributions are highlighted.
A round-robin study has been carried out to estimate the impact of the human element in small-angle scattering data analysis. Four corrected datasets were provided to participants ready for analysis. All datasets were measured on samples containing spherical scatterers, with two datasets in dilute dispersions and two from powders. Most of the 46 participants correctly identified the number of populations in the dilute dispersions, with half of the population mean entries within 1.5% and half of the population width entries within 40%. Due to the added complexity of the structure factor, far fewer people submitted answers on the powder datasets. For those that did, half of the entries for the means and widths were within 44 and 86%, respectively. This round-robin experiment highlights several causes for the discrepancies, for which solutions are proposed.
In this article, a partial selection of experiments on enhancing the impact resistance of structural components with non-metallic, textile-reinforced concrete is discussed. The focus is on the experimental investigations in which the impact resistance of thin, textile-reinforced concrete plates is characterized. The article discusses the materials, fabrics and test setup used. For the experimental work, a drop tower from the Otto Mohr Laboratory, which belongs to the Technische Universtät Dresden, was used. Furthermore, the experimental results are presented and evaluated using different methods. Based on the collected data, a suitable approach to determining the perforation velocity of an impactor through the investigated thin, textile-reinforced concrete plates is shown.
Covalent organic frameworks (COFs) are a prominent class of organic materials constructed from versatile building blocks via reversible reactions. The quality of imine-linked COFs can be improved by using amine monomers protected with benzophenone forming benzophenone imines. Here, we present a study on substituted benzophenones in COF synthesis via formal transimination. 12 para-substituted N-aryl benzophenone imines, with a range of electron-rich to electron-poor substituents, were prepared and their hydrolysis kinetics were studied spectroscopically. All substituted benzophenone imines can be employed in COF synthesis and lead to COFs with high crystallinity and high porosity. The substituents act innocent to COF formation as the substituted benzophenones are cleaved off. Imines can be tailored to their synthetic demands and utilized in COF formation. This concept can make access to previously unattainable, synthetically complex COF monomers feasible.
The performance of titanium alloy (Ti6Al4V) surfaces was investigated in lubricated reciprocating sliding tribological tests (RSTT). Special emphasis was laid on the effect of surface nanostructures in area of contact on the respective friction and wear behaviour. These so-called laser-induced periodic surface structures (LIPSS, ripples) were produced on the titanium alloy surface upon scan processing in air by an ultrashort pulsed femtosecond (fs) laser. As lubricant served two types of base oils, a pure polyalcylene-glycol, and an SAE 0W30 oil containing only antioxidants and temperature stabilizers. Tribological tests were carried out on polished as well as LIPSS covered areas using both types of base oil. A test metrics was established, combining the additive 2-ethylhexyl-zincdithiophosphate (ZDDP) or the ionic liquid [P6,6,6,14] [DEHP] (98% purity) with the respective base oils. The test metrics also considered the orientation of motion with respect to the orientation of the structures formed on the surface. Results are presented which show that the interplay between LIPSS and the local chemistry formed by the respective additives is beneficial for the tribological behaviour of the titanium alloy. Certain combinations of base oil, additive and LIPSS reduced friction and wear significantly in the tribological contact.
In our (dramatically understaffed) X-ray scattering laboratory, developing a systematic, holistic methodology1 let us provide scattering and diffraction information for more than 2100 samples for 200+ projects led by 120+ collaborators over the last five years. Combined with universal, automat-ed data correction pipelines, as well as our analysis and simulation software, this led to more than 40 papers2 in the last 5 years with just over 2 full-time staff members.
While this approach greatly improved the consistency of the results, the consistency of the samples and sample series provided by the users was less reliable nor necessarily reproducible. To address this issue, we built an EPICS-controlled, modular synthesis platform to add to our laboratory. To date, this has prepared over 1200 additional (Metal-Organic Framework) samples for us to meas-ure, analyse and catalogue. By virtue of the automation, the synthesis of these samples is automat-ically documented in excruciating detail, preparing them for upload and exploitation in large-scale materials databases alongside the morphological results obtained from the automated X-ray scat-tering analysis.
Having developed these proof-of-concepts, we find that the consistency of results are greatly im-proved by virtue of their reproducibility, hopefully adding to the reliability of the scientific findings as well. Additionally, the nature of the experiments has changed greatly, with much more emphasis on preparation and careful planning. This talk will discuss the advantages and disadvantages of this highly integrated approach and will touch upon upcoming developments.
The performance of titanium alloy (Ti6Al4V) surfaces was investigated in lubricated reciprocating sliding tribological tests (RSTT). Special emphasis was laid on the effect of surface nanostructures in area of contact on the respective friction and wear behaviour. These so-called laser-induced periodic surface structures (LIPSS, ripples) were produced on the titanium alloy surface upon scan processing in air by an ultrashort pulsed femtosecond (fs) laser. As lubricant served two types of base oils, a pure polyalcylene-glycol, and an SAE 0W30 oil containing only antioxidants and temperature stabilizers. Tribological tests were carried out on polished as well as LIPSS covered areas using both types of base oil. A test metrics was established, combining the additive 2-ethylhexyl-zincdithiophosphate (ZDDP) or the ionic liquid [P6,6,6,14] [DEHP] (98% purity) with the respective base oils. The test metrics also considered the orientation of motion with respect to the orientation of the structures formed on the surface. Results are presented which show that the interplay between LIPSS and the local chemistry formed by the respective additives is beneficial for the tribological behaviour of the titanium alloy. Certain combinations of base oil, additive and LIPSS reduced friction and wear significantly in the tribological contact.
This study was carried out to investigate the neutron transmission signal as a function of sample temperature during a welding process. A theoretical description that includes the Debye-Waller factor was used to describe the temperature influence on the neutron crosssections. Neutron imaging using a monochromatic beam helps to observe transmission variations related to the material temperature. In-situ neutron imaging of welding experiments show the distribution of the temperature in bulk steel samples. The performed finite element modelling of expected temperature distributions shows good agreement with the obtained experimental data.
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 Materials), details of any strategy documents publicly available, networks within Germany and how we engage are presented.
Considering the availability of serological and molecular biological methods, the bioassay has been paled into insignificance, although it is the only experimental method that can be used to demonstrate the infectivity of a virus. We compared goodness-of-fit and predictability power of five models for the quantification of tomato brown rugose fruit virus (ToBRFV) based on local lesion assays: the Kleczkowski model, Furumoto and Mickey models I and II, the Gokhale and Bald model (growth curve model), and the modified Poisson model. For this purpose, mechanical inoculations onto Nicotiana tabacum L. cv. Xanthi nc and N. glutionosa L. with defined virus concentrations were first performed with half-leaf randomization in a Latin square design. Subsequently, models were implemented using Python software and fitted to the number of local lesions. All models could fit to the data for quantifying ToBRFV based on local lesions, among which the modified Poisson model had the best prediction of virus concentration in spike samples based on local lesions, although data of individual indicator plants showed variations. More accurate modeling was obtained from the test plant N. glutinosa than from N. tabacum cv. Xanthi nc. The position of the half-leaves on the test plants had no significant effect on the number of local lesions.
After entry of a quarantine/regulated pathogen, infected plants shall be destroyed, and the cultivated area (e.g., greenhouse) shall be disinfected. Therefore, the selection of an effective disinfectant plays an important role. With the availability of different methods for virus quantification, we investigated the application of quantitative ELISA (qELISA), RT-qPCR (reverse transcription-quantitative polymerase chain reaction), and bioassays for the quantification of disinfectant efficacy. Therefore, we estimated the titer reduction in tomato brown rugose fruit virus (ToBRFV), a regulated pathogen, in plant sap and on germ carriers after treatment with MENNO Florades 4% for 16 h. The virus load before and after the treatment was measured with the mentioned methods. The RT-qPCR and qELISA methods showed very low efficacy in the presence of the disinfectant. Although bioassays are time-consuming, need purified particles for establishing the quantification models, and are less sensitive than RT-qPCR, they were able to quantify the differences in virus titer in the presence/absence of disinfectant. Interestingly, the bioassays reached at least the lower limit sensitivity of a qELISA. By being less sensitive to the presence of the disinfectant, bioassays proved to be the only technique for the determination of the disinfectant efficacy against ToBRFV on different germ carriers as well as on virus-infected plant sap.
In this study, a wound dressing composed of an alginate dialdehyde−gelatin (ADA-GEL) hydrogel incorporated by astaxanthin (ASX) and 70B (70:30 B2O3/CaO in mol %) borate bioactive glass (BBG) microparticles was developed through 3D printing. ASX and BBG particles sti.ened the composite hydrogel construct and delayed its in vitro degradation compared to the pristine hydrogel construct, mainly due to their cross-linking role, likely arising from hydrogen bonding between the ASX/BBG particles and ADA-GEL chains. Additionally, the composite hydrogel construct could hold and deliver ASX steadily. The composite hydrogel constructs codelivered biologically active ions (Ca and B) and ASX, which should lead to a faster, more e.ective wound-healing process. As shown through in vitro tests, the ASX-containing composite hydrogel promoted fibroblast (NIH 3T3) cell adhesion, proliferation, and vascular endothelial growth factor expression, as well as keratinocyte (HaCaT) migration, thanks to the antioxidant activity of ASX, the release of cell-supportive Ca2+ and B3+ ions, and the biocompatibility of ADA-GEL. Taken together, the results show that the ADA-GEL/BBG/ASX composite is an attractive biomaterial to develop multipurposed wound-healing constructs through 3D printing.
In the current study, we investigate an interaction under high-pressure high-temperature of single phase fcc-, hcp- and bcc-structured high-entropy alloys with hydrogen, carbon and nitrogen to obtain high-entropy hydrides, carbides and nitrides. Structural changes in high-entropy alloys upon compression and heating in the presence of these light elements are in the focus of our investigation. An easy route to high-entropy hydrides, carbides and nitrides will open new synthetic horizons in compositionally complex materials. Our study suggests that high-entropy alloys form high- entropy hydrides mainly with a composition close to M:H 1:1 ratio. Hydrides can be obtained under compression with hydrogen as a pressure compression medium or using hydrogen fluid as reactive agent.
Quantitative Microstructural Analysis - VAMAS TWA 37 & Liaison with ISO/TC 202 Microbeam Analysis
(2023)
The progress in activities on Microbeam Analysis under VAMAS/TWA 37 is reviewed. Particularly the liaison with the new projects within the ISO technical committee TC 202 is presented and discussed with respect to the identification and launching corresponding VAMAS projects. The ongoing project "FIB sample processing for TEM" is presented in detail.
Laser-induced periodic surface structures (LIPSS) and their combination with self-ordered microstructures forming hierarchical Spikes enable a large variety of different surface functionalizations for applications in the fields of optics, fluidics, tribology, or medicine. Moreover, high spatial frequency LIPSS (HSFL) provide an appealing and straightforward way for surface nanostructuring featuring spatial periods even below 100 nm – far beyond the optical diffraction limit. However, the imposed surface functionalities are usually caused by both, topographic and chemical surface alterations. For exploring these effects in detail, multi-method characterizations were performed here for HSFL and hierarchical Spikes processed on Ti-6Al-4V alloy upon irradiation with near-infrared ps-laser pulses (1030 nm wavelength, ~1 ps pulse duration, 1 – 400 kHz pulse repetition rate) under different laser and scan processing conditions. The following sample characterization involved morphological and topographical investigations by scanning electron microscopy (SEM), atomic force microscopy (AFM), stylus profilometry (SP), and white light interference microscopy (WLIM), as well as near-surface chemical analyses by X-ray photoelectron spectroscopy (XPS), hard X-ray photoelectron spectroscopy (HAXPES) and depth-profiling time-of-flight secondary ion mass spectrometry (TOF-SIMS). The results allow to qualify the laser ablation depth, the geometrical HSFL/Spikes characteristics and provide detailed insights into the depth extent and the nature of the ps-laser-induced near-surface oxidation arising from the laser-processing in ambient air and into the relevance of heat-accumulation effects at high pulse repetition rates. Moreover, the direct comparison of the HAXPES and XPS data reveals the role of surface-covering organic contaminants adsorbed from the ambient atmosphere without the uncertainties and potential sputter reduction potentially caused by ion-sputter depth profiling.
Laser-induced periodic surface structures (LIPSS) have gained remarkable attention as they represent a universal phenomenon that is often accompanying laser-processing. Such LIPSS enable a large variety of different surface functionalizations for applications in the fields of optics, fluidics, tribology, or medicine. Moreover, so-called “high spatial frequency LIPSS” (HSFL) provide an appealing and straightforward way for surface nanostructuring featuring spatial periods even below 100 nm – far beyond the optical diffraction limit. However, the imposed surface functionalities are usually caused by both, topographic and chemical surface alterations. For exploring these effects in detail, multi-method characterizations were performed here for HSFL on processed Ti- 6Al- 4V alloy upon irradiation with near-infrared ps-laser pulses (1030 nm wavelength, ~1 ps pulse duration, 1 – 400 kHz pulse repetition rate) under different laser and scan processing conditions. The sample characterization involved morphological and topographical investigations by scanning electron microscopy (SEM), atomic force microscopy (AFM), stylus profilometry (SP), and white light interference microscopy (WLIM), as well as near-surface chemical analyses by X-ray photoelectron spectroscopy (XPS), hard X-ray photoelectron spectroscopy (HAXPES) and depth-profiling time-of-flight secondary ion mass spectrometry (TOF-SIMS). The results allow to qualify the laser ablation depth, the geometrical HSFL characteristics and provide detailed insights into the depth extent and the nature of the ps-laser-induced near-surface oxidation. Significance for medical applications will be outlined.
Irradiation of solid surfaces with intense ultrashort laser pulses represents a unique way of depositing energy into materials. It allows to realize states of extreme electronic excitation and/or very high temperature and pressure and to drive materials close to and beyond fundamental stability limits. As a consequence, structural changes and phase transitions often occur along unusual pathways and under strongly nonequilibrium conditions. Due to the inherent multiscale nature — both temporally and spatially—of these irreversible processes, their direct experimental observation requires techniques that combine high temporal resolution with the appropriate spatial resolution and the capability to obtain good quality data on a single pulse/event basis. In this respect, fourth-generation light sources, namely, short wavelength and short pulse free electron lasers (FELs), are offering new and fascinating possibilities. As an example, this talk will discuss the results of scattering experiments carried out at the FLASH free electron laser at DESY (Hamburg, Germany), which allowed us to resolve laser-induced structure formation at surfaces on the nanometer to submicron length scale and in temporal regimes ranging from picoseconds to several nanoseconds with sub-picosecond resolution. The current status and future perspectives in this field via exploiting the unique possibilities of these 4th-generation light sources will be discussed.
The precipitation of struvite, a magnesium ammonium phosphate hexahydrate (MgNH₄PO₄ · 6H₂O) mineral, from wastewater is a promising method for recovering phosphorous. While this process is commonly used in engineered environments, our understanding of the underlying mechanisms responsible for the formation of struvite crystals remains limited. Specifically, indirect evidence suggests the involvement of an amorphous precursor and the occurrence of multi-step processes in struvite formation, which would indicate non-classical paths of nucleation and crystallization. In this study, we use synchrotron-based in situ x-ray scattering complemented by cryogenic transmission electron microscopy to obtain new insights from the earliest stages of struvite formation. The holistic scattering data captured the structure of an entire assembly in a time-resolved manner. The structural features comprise the aqueous medium, the growing struvite crystals, and any potential heterogeneities or complex entities. By analysing the scattering data, we found that the onset of crystallization causes a perturbation in the structure of the surrounding aqueous medium. This perturbation is characterized by the occurrence and evolution of Ornstein-Zernike fluctuations on a scale of about 1 nm, suggesting a non-classical nature of the system. We interpret this phenomenon as a liquid-liquid phase separation, which gives rise to the formation of the amorphous precursor phase preceding actual crystal growth of struvite. Our microscopy results confirm that the formation of Mg-struvite includes a short-lived amorphous phase, lasting >10 s.
In our (dramatically understaffed) X-ray scattering laboratory, developing a systematic, holistic methodology let us provide scattering and diffraction information for more than 2100 samples for 200+ projects led by 120+ collaborators. Combined with automated data correction pipelines, and our analysis and simulation software, this led to more than 40 papers in the last 5 years with just over 2 full-time staff members.
This year, our new, modular synthesis platform has made more than 1000 additional samples for us to analyse and catalogue. By virtue of the automation, the synthesis of these samples is automatically documented in excruciating detail, preparing them for upload and exploitation in large-scale materials databases. Having developed these proof-of-concepts, we find that materials research itself is changed dramatically by automating dull tasks in a laboratory.
This talk is intended to spark ideas and collaborations by providing an overview of: 1) the current improvements in our scattering laboratory methodology, 2) introducing our open, modular robotic platform that is used for systematic sample preparation, and 3) demonstrating the data structure of the synthesis logs and measurements. Finally, the remaining bottlenecks and points of attention across all three are highlighted.
In this talk, the importance of metadata is underscored by real-world examples.
Metadata is essential to alleviating the reproducibility crises in science. This imples that a wide range of metadata must be collected, with a heavy emphasis on the automated collection of such metadata. This must subsequently be organized in an intelligible, archival structure, when possible with units and uncertainties.
Such metadata can aid in improving the usage efficiency of instrumentation, as is demonstrated on the MOUSE instrument. This metadata can now be used to connect the various aspects of the holistic experimental procedure to gain better insights on the materials structure.
A second example shows the extraction and organization of such metadata from an automated materials development platform, collected during the synthesis of 1200 samples. These metadata from the synthesis can then be linked to the results from the analysis of these samples, to find direct correlations between the synthesis parameters and the final structure of the materials.
The X-ray intensities of the K-, L- and M-lines of copper, zirconium and tungsten have been measured with an energy-dispersive X-ray spectrometer of known efficiency as function of photon energy. X-ray production efficiencies were determined from the measured intensities for Kα- and L-series of Cu and Zr and for the L- and M-series of W. These data were compared to calculated X-ray production efficiencies based on the widely used matrix correction models of Pouchou and Pichoir (XPP) and Bastin (PROZA96).
Our results indicate that a replacement of the stopping power in the PROZA96 algorithm by expressions of Joy and Jablonski has only a minor influence on the calculated X-ray production efficiencies. In contrast, the modifications of the ionization cross-section show a stronger effect. We replaced the ionization cross-sections for K lines of the PROZA96 algorithm with different models.
The results for L- and M-Lines are different. For the L-lines of Cu the original XPP and PROZA96 models show the best agreement while using the Bote cross-sections result in an overestimation. For the Zr-L and W-L1, -L2, -L3 X-ray production efficiencies, the Bote cross-sections lead to a significant improvement compared to all other models. The original XPP model represents the best agreement for the M5 efficiencies but underestimates the M4 efficiencies.
There is no superior model or modification because the parameter sets in the models need to be aligned to each other. However, using the ionization cross-sections of Bote, which are based on quantum mechanical calculations, show promising results in many cases.
Anhand der Wirksumme ist eine Abschätzung des legierungsabhängigen Einflusses auf den Korrosionswiderstand gegen chloridhaltige Medien möglich. Die berechneten Werte sind nur bei optimaler Wärmebehandlung und Verarbeitung zutreffend.
Die Anwendung einer einfachen Formel unter Berücksichtigung von Chrom, Molybdän und Stickstoff ist in der Regel völlig ausreichend. Das daraus abgeleitete Ranking von Werkstoffen ist für diverse technische Regelwerke und zur Unterstützung der Werkstoffauswahl geeignet.
Für die Warenein-/Ausgangskontrolle ist die alleinige Feststellung der Wirksumme unzureichend. Ergänzende Korrosionsuntersuchungen/-prüfungen zur Beschreibung des Korrosionswiderstandes sind dafür notwendig. Gleiches gilt für die Beurteilung von Schadensfällen. Hier sind Verarbeitung, Einsatzbedingungen und die Konstruktion von ausschlaggebender Bedeutung.
Die Bestimmung der Nanopartikelgrößen- und -formverteilung nach OECD TG 125 mit einem Differentiellen Mobilitäts Analyse System (DMAS), auch bekannt als SMPS, wird vorgestellt:
- Generelles Messprinzip
- Welchen Durchmesser misst die Methode?
- Welche Partikel kann diese Methode messen?
- Welche Informationen kann diese Methode liefern?
- Wo stößt die Methode an ihre Grenzen?
- Implementierung und Datenauswertung,
- Reporting.
Anschließend wurde eine Q&A-Session für DMAS/SMPS organisiert.
OECD Prüfrichtlinie 125
(2023)
Diese Präsentation ist eine Einführung in die OECD TG 125 zur Bestimmung der Partikelgrößen von Nanomaterialien. Es wird auf die verchiedenen Probleme der Partikelgrößenbestimmung eingegangen wie z.B. verschiedene Oberflächenschichten, Äquivalenzdurchmesser und Verteilungsfunktionen. Gleichzeitig werden die neuen Begrifflichkeiten eingeführt, die in der TG 125 definiert neu werden.
Ellipsometry is a highly valuable technology for bridging different measurement methods. As a fast, highly sensitive, and non-destructive optical technique with low environmental requirements, it is ideal for transporting measurement accuracy and for up-scaling measurements in the production environment. It can be used for highly precise determination of properties, material identity and correctness confirmation, as well as defect detection.
Comparable, traceable, and accurate electrical measurements, especially at small scales are one of the biggest challenges in the development of the electrical and electronic devices of the future.
In this project, we develop structured thin layer systems of the transparent conductive material indium tin oxide (ITO) to prove the concept of using these systems as standards for conductivity and permittivity. The layers are produced in a reactive magnetron sputtering process from raw ITO targets with additional oxidation achieved by oxygen injection. We present results of a study correlating the coating process conditions with the properties of the final layer material. We found that especially the temperature development during coating is of key importance and determines the layer properties to a large extent. We will discuss questions of homogeneity and reproducibility of the coating processes used. The finished layers undergo lithographic structuring and etching to produce patterns to serve as reference structures for scanning probe electrical measurements. TCOs have a large variety of applications. In this work we also study the usability of ITO for other purposes and investigate the stability of this material under application conditions.
Die Bundesanstalt für Materialforschung und -prüfung (BAM) ist eine forschende Bundesoberbehörde und Einrichtung der Ressortforschung der Bundesrepublik Deutschland. Unter ihrer Leitlinie „Sicherheit in Technik und Chemie“ ist sie zuständig für die öffentliche technische Sicherheit und für metrologische Aufgaben in der Chemie. Das Aufgabenspektrum der BAM, das sich an aktuellen Fragestellungen aus Wissenschaft, Wirtschaft, Politik und Normung orientiert, bietet sehr viele interessante Tätigkeitsfelder für Naturwissenschaftler*Innen und Ingenieur*Innen.
Newly developed methodical approaches with an emphasis on correlative imaging analysis of morphology and chemistry of nanomaterials will be presented. Correlative imaging by high-resolution SEM with STEM-in-SEM as well as with EDS, and further with AFM, or with the new technique TKD (Transmission Kikuchi Diffraction) will be explained on various examples of nanostructures, both as starting materials and as embedded/functionalized nanoparticles in products. The unique analytical benefits of the Auger electron probe as a veritable nano-tool for the local surface chemistry will be highlighted. Examples of hybrid analysis of the bulk of nanomaterials by X-ray Spectroscopy and the highest surface-sensitive methods XPS and ToF-SIMS as advanced surface characterization methods available in the Competence Centre nano@BAM will be showed. Particularly for the spatially resolved analysis of the chemistry of nanostructures, such in-depth and lateral gradients of chemistry within mesoporous thin layers, or the completeness of the shells of core-shell nanoparticles, the latter methods are inherent.
Other dedicated developments like approaches for the quantitative determination of the porosity of thin mesoporous layers by electron probe microanalysis (EPMA) with SEM or the quantitative determination of the roughness of particle surface by high-resolution imaging with electron microscopy will be also presented.
An isotopic effect of normal (H2O) vs. heavy water (D2O) is well known to fundamentally affect structure and chemical properties of proteins, for instance. Here we correlate results from small angle X-ray and neutron scattering (SAXS, SANS) with high-resolution scanning transmission electron microscopy to track the evolution of CdS nanoparticle size and crystallinity from aqeuous solution in presence of the organic ligand ethylenediaminetetraacetate (EDTA) at room temperature in both H2O and D2O. We provide evidence via SANS experiments that exchanging H2O by D2O impacts nanoparticle formation by changing the equilibria and dynamics of EDTA clusters in solution as investigated by nuclear magnetic resonance. The colloidal stability of the CdS nanoparticles, covered by a layer of [Cd(EDTA)]2- complexes, is significantly reduced in D2O despite the strong stabilizing effect of EDTA in suspensions of normal water. Hence, conclusions about nanoparticle formation mechanisms from D2O solutions can bare limited transferability to reactions in normal water due to isotopic effects, which thus need to be discussed for contrast match experiments.
Only the nano-scaled structure of the nanocomposite and the dispersion of nanoparticles within the polymer matrix harbor multifunctional potential including superior fire retardancy. Thus, this chapter focuses on the dispersion of nanoplates, based mainly on studies of layered silicates and graphene/graphene-related nanoplates. The nanostructure and properties of the nanocomposites are dependent mainly on thermodynamic and kinetic factors during preparation. Improving nano-dispersion often directly improves flame retardancy. Therefore, the modification of the nanoplates as well as the preparation of nanocomposites becomes very important to control this dispersion. The dispersion of nanoplates functions as a prerequisite for the formation of an efficient protective layer, changing the melt flow and dripping behavior, or the improvement of the char properties.
Photoluminescence Quantum Yields of Luminescent Nanocrystals and Particles in the UV/vis/NIR/SWIR
(2023)
The rational design of functional luminescent materials such as semiconductor quantum dots and lanthanide-based upconversion nanoparticles, all photophysical and mechanistic studies, and the comparison of different emitters require accurate and quantitative photoluminescence measurements. Particularly the reliable determination of the key performance parameter photoluminescence quantum yield (f), the number of emitted per absorbed photons, and the brightness are of special importance for luminescence applications in the life and material sciences and nano(bio)photonics.[1] In this context, examples for absolute measurements of the photoluminescence quantum yields of UV/vis/NIR/SWIR emissive semiconductor quantum dots and rods, made from different materials, and spectrally shifting lanthanide upconversion nanocrystals with different surface chemistries in transparent matrices are presented including excitation wavelength and power density dependent studies utilizing integration sphere spectroscopy.[2,3] In addition, procedures for the absolute determination of the photoluminescence quantum yields of scattering dispersions of larger size quantum rods and differently sized inorganic particles have been developed as well as procedures for the characterization of solid luminescent nanomaterials such as different perovskites and YAG:Cer converter materials.[4] Thereby, challenges and pitfalls of f measurements in different wavelength regions including the SWIR and material-specific effects related to certain emitter classes are addressed, achievable uncertainties are quantified, and relative and absolute measurements of photoluminescence quantum yield measurements are compared to underline limitations of the former approach. Finally, a set of novel UV/vis/NIR quantum yield standards is presented including their certification with a complete uncertainty budget.[5]
Glimpses of the Future ✨: Advancing X-ray Scattering in an Automated Materials Research Laboratory
(2023)
In our (dramatically understaffed) X-ray scattering laboratory, developing a systematic, holistic methodology1 let us provide scattering and diffraction information for more than 2100 samples for 200+ projects led by 120+ collaborators. Combined with automated data correction pipelines, and our analysis and simulation software, this led to more than 40 papers2 in the last 5 years with just over 2 full-time staff members.
This year, our new, modular synthesis platform has made more than 1000 additional samples for us to analyse and catalogue. By virtue of the automation, the synthesis of these samples is automatically documented in excruciating detail, preparing them for upload and exploitation in large-scale materials databases. Having developed these proof-of-concepts, we find that materials research itself is changed dramatically by automating dull tasks in a laboratory.
This talk is intended to spark ideas and invite collaborations by providing an overview of: 1) the current improvements in our wide-range X-ray scattering laboratory methodology, 2) Introduce some of our open-source analysis and simulation software, touching on scattering, diffraction and PDF, and 3) introducing our open, modular robotic platform for systematic sample preparation. Finally, the remaining bottlenecks and points of attention across all three are highlighted.
The second talk for the Swiss Society for Crystallography (SSCr) workshop on SAXS will highlight the data processing challenges, holistic experimental workflow developments, and the pitfalls. In particular, the following items will be addressed:
- The importance of data processing and estimating uncertainty
- A universal correction pipeline – away with the headaches, at least for this step!
- Experiment planning part 2, some tips and advice to improve your corrected data.
- Sample preparation, background selection, some tips and advice to improve your corrected data.
- Automate for your mental well-being; electronic logbooks, measurement catalogs and workflow management software
- Life on the edge: several pitfalls to avoid…
This talk for the Swiss Society for Crystallography (SSCr) workshop on SAXS will introduce scattering from various angles, focusing in particular on:
- Information content of X-ray scattering experiments, three entry points…
- An introduction to Fourier Transforms
- Sample criteria, compatibility, and selection
- Key indicators of a measurement – where is the information?
- Key indicators of measurement quality
- Experiment planning, the basics
In our (dramatically understaffed) X-ray scattering laboratory, developing a systematic, holistic methodology let us provide scattering and diffraction information for more than 2100 samples for 200+ projects led by 120+ collaborators. Combined with automated data correction pipelines, and our analysis and simulation software, this led to more than 40 papers in the last 5 years with just over 2 full-time staff members.
This year, our new, modular synthesis platform has made more than 1000 additional samples for us to analyse and catalogue. By virtue of the automation, the synthesis of these samples is automatically documented in excruciating detail, preparing them for upload and exploitation in large-scale materials databases.
This talk is intended to spark ideas and invite collaborations by providing an overview of: 1) the current improvements in our wide-range X-ray scattering laboratory methodology, and 2) introducing our open, modular robotic platform for systematic sample preparation.
Hierarchically porous, high‐surface‐area silica materials are excellent candidates for multiple applications like catalysis and environmental remediation. Shaping these materials with additive manufacturing (AM) techniques, like robocasting, could enable their use with the benefit of on‐demand, customized shaping and maximizing performance. Herein, ordered mesoporous silica COK‐12 slurries were robocasted into monoliths, containing different ratios of uncalcined COK‐12 and sodium bentonite (0–25 wt.%). The rheology of the mixed slurries is characterized by lower flow indexes (0.69 vs. 0.32) and higher yield stresses (96 vs. 259 Pa) compared to pure COK‐12 ones. Monoliths were printed in woodpile structures and calcined at 600°C. Micro‐CT measurements showed a linear shrinkage of 25% after calcination. Mechanical characterization showed increased uniaxial strength (0.20 ± 0.07 to 1.0 ± 0.3 MPa) with increasing binder/solids ratio from 13 to 25%. The amorphous, mesoporous structure of COK‐12 was retained. The structures exhibited open porosities of 52 ± 4% and showed higher specific mesopore volumes, and increased average mesopore size (6 vs. 8 nm) compared to COK‐12. Small‐angle x‐ray scattering analysis revealed an increased lattice parameter (10.3 vs. 11.0 nm) and reduced wall thickness (3.1 nm vs. 4.1 nm) of the COK‐12 in the monoliths. These properties indicate suitability for their application as porous supports and adsorbents.
Due to the extremely high specific surface area of nanoparticles and corresponding potential for adsorption, the results of surface analysis can be highly dependent on the history of the particles, particularly regarding sample preparation and storage. The sample preparation method has, therefore, the potential to have a significant influence on the results. This report describes an interlaboratory comparison (ILC) with the aim of assessing which sample preparation methods for ToF-SIMS analysis of nanoparticles provided the most intra- and interlaboratory consistency and the least amount of sample contamination. The BAM reference material BAM-P110 (TiO2 nanoparticles with a mean Feret diameter of 19 nm) was used as a sample representing typical nanoparticles. A total of 11 participants returned ToF-SIMS data,in positive and (optionally) negative polarity, using sample preparation methods of “stick-and-go” as well as optionally “drop-dry” and “spin-coat.” The results showed that the largest sources of variation within the entire data set were caused by adventitious hydrocarbon contamination or insufficient sample coverage, with the spin-coating protocol applied in this ILC showing a tendency toward insufficient sample coverage; the sample preparation method or the participant had a lesser influence on results.
Test artifact for fs-LDW
(2023)
Ionic Liquid Crystals are ionic liquids that exhibit liquid crystalline mesomorphism together with ionic conductivity. As known confined liquid crystal mesophases can show an anomalous dynamics and phase behavior. Investigations considering the factors controlling the macroscopic properties of ILCs in confinement are scare in the literature. This study reports the molecular mobility, and the phase transition behavior of a guanidinium based columnar ILC confined in the nanopores of self-ordered anodic aluminum oxide membranes of various pore diameters (25 – 180 nm) using Broadband Dielectric Spectroscopy (BDS), calorimetry and X-ray scattering. It is aimed to reveal in which way the pore size as well as the pore surface wettability (hydrophobic or hydrophilic) alters the molecular dynamics, and phase transition behavior for this system. These properties are crucial for applications. The DSC investigations reveal: (i) the phase transition temperature for the transition from the plastic crystalline to the crystalline-liquid state has non-monotonic dependence versus the inverse pore diameter and (ii) the transition from the liquid crystalline to the isotropic phase is suppressed for all nanoconfined samples. This transition suppressed in the thermal signal was evidenced by BDS and X-ray scattering. It is discussed as a continuous phase transition taking place in the pores instead of a discontinuous first order transition as observed for the bulk. BDS investigations show different relaxation processes for the bulk and the nanoconfined ILC. Molecular origins for various relaxation processes are discussed and suggested. It is further shown that the self-assembly of this ILC is dynamic in nature which might apply for other ILCs too. The obtained results will have implications for the nanoscale applications of ionic liquid crystals.
Bulk metallic glasses (BMG) are amorphous metal alloys known for their unique physical and mechanical properties. In the present study, the formation of femtosecond (fs) laser-induced periodic surface structures (LIPSS) on the Zr-based BMGs Zr46Cu46Al8, Zr61Cu25Al12Ti2, Zr52.5Cu17.9Al10Ni14.6Ti5 (Vit105) and Zr57Cu15.4Al10Ni12.6Nb5 (Vit106) was investigated as a function of their different chemical composition. For this purpose, LIPSS were generated on the sample surfaces in an air environment by fs-laser irradiation (λ = 1025 nm, τ = 300 fs, frep = 100 kHz). The surface topography was characterized by scanning electron microscopy and atomic force microscopy. Moreover, the impact of LIPSS formation on the structure and chemical surface composition was analyzed before and after fs-laser irradiation by X-ray diffraction and X-ray photoelectron spectroscopy as well as by transmission electron microscopy in combination with energy dispersive X-ray spectroscopy. Despite the different chemical composition of the investigated BMGs, the fs-laser irradiation resulted in almost similar properties of the generated LIPSS patterns. In the case of Zr61Cu25Al12Ti2, Vit105 and Vit106, the surface analysis revealed the preservation of the amorphous state of the materials during fs-laser irradiation. The study demonstrated the presence of a native oxide layer on all pristine BMGs. In addition, fs-laser irradiation results in the formation of laser-induced oxide layers of larger thickness consisting of an amorphous ZrAlCu-oxide. The precise laser-structuring of BMG surfaces on the nanoscale provides a versatile alternative to thermoplastic forming of BMG surfaces and is of particular interest for the engineering of functional material surfaces.
Iron Oxide Nanocubes as a New Certified Reference Material for Nanoparticle Size Measurements
(2023)
The rational design and increasing industrial use of nanomaterials require a reliable characterization of their physicochemical key properties like size, size distribution, shape, and surface chemistry. This calls for nanoscale reference materials (nanoRMs) for the validation and standardization of commonly used characterization methods closely matching real-world nonspherical nano-objects. This encouraged us to develop a nonspherical nanoRM of very small size consisting of 8 nm iron oxide nanocubes (BAM-N012) to complement spherical gold, silica, and polymer nanoRMs. In the following, the development and production of this nanoRM are highlighted including the characterization by transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS) as complementary methods for size and shape parameters, homogeneity and stability studies, and calculation of a complete uncertainty budget of the size features. The determination of the nanocubes’ edge length by TEM and SAXS allows a method comparison. In addition, SAXS measurements can also provide the mean particle number density and the mass concentration. The certified size parameters, area equivalent circular diameter and square edge length, determined by TEM with a relative expanded uncertainty below 9%, are metrologically traceable to a natural constant for length, the very precisely known (111) lattice spacing of silicon. Cubic BAM-N012 qualifies as a certified nanoRM for estimating the precision and trueness, validation, and quality assurance of particle size and shape measurements with electron microscopy and SAXS as well as other sizing methods suitable for nanomaterials. The production of this new iron oxide nanocube RM presents an important achievement for the nanomaterial community, nanomaterial manufacturers, and regulators.
The basic principles of generation of electrons and X-rays and the operation of SEM/EDS instruments are presented. Examples, recent successes and challenges in the analysis of nano-structures are given. Multi-method analytical approaches with the focus on imaging the nanoscale are highlighted. Details on the sample preparation and persepective on the automated analysis (sample preparation, measurement, data analyis and storage) are given. Metrological aspects, standardisation, and reference materials are also emphasized by examples.
With femtosecond-laser direct writing (fs-LDW) maturing in all aspects as a manufacturing technology, a toolset for quality assurance must be developed. In this work we introduce a first of its kind test artifact. Test artifacts are standardized 3D models with specific geometric features to evaluate the performance of writing parameters. Test artifacts are already common in other 3D additive manufacturing technologies e.g. selective laser melting. The test artifact introduced in this work was developed in particular to accommodate the high geometrical resolution of fs-LDW structures and the limited possibilities to examine the resulting structure. Geometric accuracy, surface adhesion as well as confocal Raman spectroscopy results were considered when evaluating the design of the test artifact. We will explain the individual features and design considerations of our fs-LDW test artifact. The difference between two slicers, Cura and 3DPoli, and the implications on measured feature sizes and the general shape is quantified. The measured geometries are used to derive a general design guide for a specific combination of photoresists, laser power and scanning speed and to analyze the geometric accuracy of a structure produced using these guidelines. The shown test artifact is publicly available as STL file on GitHub (https://github.com/BAMresearch/2PP-TestArtifact) and in the supplement.
Surface-functionalized polymer beads encoded with molecular luminophores and nanocrystalline emitters such as semiconductor nanocrystals, often referred to as quantum dots (QDs), or magnetic nanoparticles are broadly used in the life sciences as reporters and carrier beads. Many of these applications require a profound knowledge of the chemical nature and total number of their surface functional groups (FGs), that control bead charge, colloidal stability, hydrophobicity, and the interaction with the environment and biological systems. For bioanalytical applications, also the number of groups accessible for the subsequent functionalization with, e.g., biomolecules or targeting ligands is relevant. In this study, we explore the influence of QD encoding on the amount of carboxylic acid (COOH) surface FGs of 2 μm polystyrene microparticles (PSMPs). This is done for frequently employed oleic acid and oleylamine stabilized, luminescent core/shell CdSe QDs and two commonly used encoding procedures. This included QD addition during bead formation by a thermally induced polymerization reaction and a post synthetic swelling procedure. The accessible number of COOH groups on the surface of QD-encoded and pristine beads was quantified by two colorimetric assays, utilizing differently sized reporters and electrostatic and covalent interactions. The results were compared to the total number of FGs obtained by a conductometric titration and Fourier transform infrared spectroscopy (FTIR). In addition, a comparison of the impact of QD and dye encoding on the bead surface chemistry was performed. Our results demonstrate the influence of QD encoding and the QD-encoding strategy on the number of surface FG that is ascribed to an interaction of the QDs with the carboxylic acid groups on the bead surface. These findings are of considerable relevance for applications of nanoparticle-encoded beads and safe-by-design concepts for nanomaterials.
Current challenges and objectives for non-invasive optical bioimaging are deep tissue penetration, high detection sensitivity, high spatial and temporal resolution, and fast data acquisition. A promising spectral window to tackle these challenges is the short-wave infrared (SWIR) ranging from 900 nm to 1700 nm where scattering, absorption, and autofluorescence of biological components are strongly reduced compared to the visible/NIR. At present, the best performing SWIR contrast agents are based on nanomaterials containing toxic heavy-metal ions like cadmium or lead, which raises great concerns for biological applications. Promising heavy-metal free nanoscale candidates are gold nanoclusters (AuNCs) and Ag2S nanoparticles (NPs). The photoluminescence (PL) of both types of nanomaterials is very sensitive to their size, composition of their surface ligand shell, and element composition, which provides an elegant handle to fine-tune their absorption and emission features and boost thereby the size of the signals recorded in bioimaging studies.
Aiming for the development of SWIR contrast agents with optimum performance, we dived deeper into the photophysical processes occurring in these nanomaterials, thereby exploring in depth how the environment, surface ligand composition, and the incorporation of transition metals influence the optical properties of AuNCs and Ag2S NPs. We observed a strong enhancement of the SWIR emission of AuNCs upon exposure to different local environments (in solution, polymer, and in the solid state). Addition of metal ions such as Zn2+ to Ag2S based NPs led to a strong PL enhancement, yielding PL quantum yields of about 10% and thus making them highly suitable for non-invasive deep imaging of vascular networks and 3D fluid flow mapping.
Thin polymeric films are of great importance of high number of high-tech applications for instance in sensors and nanoelectronics. Form the scientific point of view thin films with thickness below 100 nm are ideal model systems to study confinement effects on its properties for instance on the molecular relaxation processes. In this contribution an overview is presented about the behavior of different systems as investigated by nanosized relaxation spectroscopy like broadband dielectric spectroscopy employing nano structured capacitors and AC chip calorimetry complimented by ellipsometry. The systems considered are PVME1, PVME/PS blends2,3 P2VP4, PBAC5 and polysulfone6. Besides the film also the adsorbed layer on the substrate prepared by a leaching approach and investigated by AFM is considered.1,4-7. For these investigationsss it is found that the adsorbed layer itself exhibits a relaxation dynamics which might be assigned either to molecular motions or to adsorptions desorption kinetics.
The rational design of next generation molecular and nanoscale reporters and the comparison of different emitter classes require the determination of the fluorometric key performance parameter fluorescence quantum yield (Φf), i.e., the number of emitted photons per number of absorbed photons. Main prerequisites for reliable Φf measurements, which are for transparent luminophore solutions commonly done relative to a reference, i.e., a fluorescence quantum yield standard of known Φf, are reliable and validated instrument calibration procedures to consider wavelength-, polarization-, and time-dependent instrument specific signal contributions, and sufficiently well characterized fluorescence quantum yield standards. As the standard’s Φf value directly contributes to the calculation of the sample’s Φf, its accuracy presents one of the main sources of uncertainty of relative Φf measurements. To close this gap, we developed a first set of 12 fluorescence quantum yield standards, which absorb and emit in the wavelength region of 330−1000 nm and absolutely determined their Φf values with two independently calibrated integrating sphere setups.
Criteria for standard selection and the configuration of these novel fluorescence reference materials are given, and the certification procedure is presented including homogeneity and stability studies and the calculation of complete uncertainty budgets for the certified Φf values. The ultimate goal is to provide the community of fluorescence users with available reference materials as a basis for an improved comparability and reliability of quantum yield data since the measurement of this spectroscopic key property is an essential part of the characterization of any new emitter.
In recent years, chromium (III) complexes have received a lot of attention as novel near-infrared (NIR) emitters. This interest was triggered by the report on the first molecular ruby Cr(ddpd)2(BF4)3 with a high photoluminescence quantum yield of 13.7% of its near infrared (NIR) emission band and a long luminescence lifetime of 1.122 ms at room temperature. Meanwhile, the influence of triplet oxygen, temperature, and pressure on the optical properties of different molecular rubies have been assessed. These features make these molecular rubies promising candidates for multi-analyte optical sensing applications and the generation of singlet oxygen for photocatalysis and photodynamic therapy. However, in an oxygen-containing environment, the photoluminescence quantum yields and luminescence lifetimes of these chromium(III) complexes show only very small values. This hampers their application as NIR luminescence labels. This application, that cannot be tackled by conventional deoxygenating approaches, requires suitable strategies to protect the luminescence of the chromium(III) complexes from oxygen quenching. Typical approaches to reduce the oxygen sensitivity of long-lived luminophores include the encapsulation into an oxygen-shielding matrix or less commonly employed, by tuning the bulkiness of the ligands for oxygen-sensitive coordination compounds. An elegant approach to reduce the undesired luminescence quenching by triplet oxygen explored by us presents the incorporation of these chromium(III) complexes into amorphous, non-porous silica nanoparticles, that can be simply surface functionalized, e.g., with targeting ligands and/or other sensor molecules. This can enable the use of such chromium(III) complexes as reporters for bioanalytical assays and bioimaging without the need to introduce reactive groups into the ligands and can pave the road to lifetime tuning.
In this work, as first proof-of-concept experiments, a set of chromium (III) complexes constituting of different ligands and counter anions, were embedded into the core of silica nanoparticles. As an alternative synthesis strategy, selected complexes were incorporated into a silica shell formed around the core of self-made silica nanoparticles. Subsequently, the optical properties of the resulting luminescent silica nanoparticles were spectroscopically assessed by steady state and time-resolved luminescence spectroscopy. First results of time-resolved luminescence measurements of the Cr(ddpd)2(PF6)3 complex incorporated into 25nm large silica nanoparticles dispersed in aerated water in comparison to the decay kinetics obtained for this complex in acetonitrile in air showed an increase in lifetime from 46 µs to 1147 µs. This confirming our design concept of nanoscale NIR emissive Cr(III) reporters.
At present, the field of research on nanostructures is actively developing, which is due to their unique physico-chemical properties compared to bulk materials. Many research activities are focused on obtaining nanocomposites, which combine various types of nanostructures with different properties and function. For example, the development of magneto-luminescent nanocomposites makes it possible to use their luminescence for optical imaging, and their magnetic properties for magnetic targeted delivery and as agents of hyperthermia and magnetic resonance imaging.
My master studies as part of the project Goszadanie 2019-1080 at ITMO were focused on the investigation of nanocomposites, consisting of semiconductor quantum dots (QDs) as luminescent component and superparamagnetic iron oxide nanoparticles (SPIONs) as magnetic one, in solution and during their incubation with HeLa cells. The spectrally resolved analysis of the QD photoluminescence (PL) kinetics of the free QDs and the QDs incorporated in these nanocomposites undergoing energy transfer processes allowed for (1) understanding the reasons for the quenching of QD luminescence in cells, (2) evaluating the average distance between the QDs and, based on this, concluding the degree of QD aggregation in cells, and (3) drawing conclusions about the QD-quencher composites integrity in cells. Overall, the analysis of the PL kinetics confirmed that QDs and SPIONs remain bound in the obtained nanocomposites during incubation with cells.
To ensure the successful advancement of nanomaterials in biomedicine and the transition from their laboratory preparation and studies to their use in different applications and in industry, it is crucial to develop reliable measurement methods and reference materials candidates for the characterization of functional nanomaterials and assessing the quality of the obtained nanostructures. My recently started project at BAM, which is part of the EU metrology project MeTrINo, will be devoted to this topic. There we will focus on the development of methodologies for the synthesis and characterization of iron oxide nanoparticles, already used in biomedicine, and multi-element lanthanide-based nanoparticles with attractive upconversion luminescence, as reference materials with high monodispersity and reproducibility. Also, these nanoparticles will be functionalized with organic dyes for optical imaging and, probably, the study of the energy transfer phenomena.
In recent years, the demand for reliable, versatile, fluorescent pH and oxygen sensors has increased rapidly in many biomedical applications since these analytes are important indicators of cell function or certain diseases. Therefore, sensor particles are needed that are small enough to penetrate cells, non-toxic, and allow for close-up optical monitoring. When developing such sensor systems, one must consider the pH and oxygen range detectable by the sensor dye and the matrix material of the used carrier particles. Here, we present the development of pH- and oxygen-responsive polymeric beads functionalized with fluorescent dyad molecules that consist of an analyte-responsive fluorophore and an analyte-inert dye.
Optical pH sensors utilizing colorimetric or fluorescent indicator dyes are highly promising in many biomedical and life science applications where electrochemical sensors fail. For instance, optical sensors are not prone to electrical interferences, they are noninvasive and enable remote measurements. Moreover, fluorescence detection is very fast, highly sensitive, and provides several readout parameters ideal for multiplexing with nanometer resolution using simple, inexpensive, and miniaturizable instrumentation. Here, we present the design of a dyad sensor molecule, consisting of an analyte-responsive and an analyte inert reference fluorophore.
Inelastic incoherent neutron time-of-flight scattering was employed to investigate the low-frequency vibrational density of states (VDOSs) for a series of glassy Janus-poly(tricyclononenes), which consist of a rigid main chain and flexible alkyl side chains. Here, the length of the flexible side chains was systematically varied from propyl to octyl. Such materials have potential applications as active separation layers in gas separation membranes as a green future technology, especially for the separation of higher hydrocarbons. From the morphological point of view, the Janus polynorbornenes undergo a nanophase separation into alkyl side chain-rich nanodomains surrounded by a rigid polynorbornene matrix. Here, the influence of the nanophase-separated structure on the low-frequency VDOS is investigated from a fundamental point of view. The low-frequency VDOSs of these Janus polynorbornene show excess contributions to the Debye type VDOS known as the Boson peak (BP) for all side chain lengths. Due to the high incoherent scattering cross-section of hydrogen, most of the scattering comes from the alkyl side chain-rich domains.
Compared to conventional glass-forming materials, in the considered Janus polynorbornenes, the BP has a much lower intensity and its frequency position is shifted to higher values. These experimental results are discussed in terms of the nanophase-separated structure where the alkyl chain-rich domains were constrained by the surrounding matrix dominated by the rigid backbone. With increasing alkyl chain length, the size of the alkyl chain-rich domains increases. The frequency position of the BP shifts linearly to lower frequencies with the size of these nanodomains estimated from X-ray measurements. The obtained results support the sound wave interpretation to the BP
SASfit 0.94.12
(2023)
Small-angle scattering is an increasingly common method for characterizing particle ensembles in a wide variety of sample types and for diverse areas of application. SASfit has been one of the most comprehensive and flexible curve-fitting programs for decades, with many specialized tools for various fields.
Accurate characterisation of the morphology (size) and chemistry of graphene-related 2D materials (GR2M) is key in understanding their extraordinary functionalities. Hence, not only the tailoring of these functionalities aiming at applications of increased-performance becomes possible, but also the correlation of the physico-chemical properties with the understanding of the potential toxicity eventually enables a safe and sustainable development of the GR2M for new applications. Whilst AFM and Raman Spectroscopy are recommended to measure the thickness of GO flakes, Scanning Electron Microscopy (SEM) is the most suited method to assess their lateral size, which varies between tens of µm down to below 100 nm. In this paper, procedures for the accurate determination of lateral size of graphene oxide (GO) flakes by SEM are presented. The prerequisite for accurate flake size analysis is the proper sample preparation, i.e. deposition of ideally isolated flakes on a substrate, with the flakes being unfolded, non-overlapped, parallel with the substrate, and having a high coverage density. Examples of optimum image caption conditions and image analysis procedures will be presented. The size descriptors and their measurement are described in the context of the corresponding analysis approach: i) length and width of the flakes with a quick and rough, but robust procedure, and ii) exact contouring of the flakes as part of a highly accurate, but more time-consuming measurement approach. The possibility of application of automated image analysis is discussed as the alternative to the manual flakes analysis.
Since its isolation, graphene has received growing attention from academia and industry due to its unique properties. However, the “what is my material” barrier hinders further commercialization. X-ray photoelectron spectroscopy (XPS) is considered as a method of choice for the determination of the elemental and chemical composition. In this work the influence of the morphology of graphene particles on the XPS results is studied and investigated as a function of X-ray energy, using conventional XPS with Al K𝜶 radiation and hard X-ray photoemission spectroscopy (HAXPES) using Cr K𝜶 radiation. Thereby, the information depth is varied between 10 and 30 nm. For this purpose, two commercial powders containing graphene nanoplatelets with lateral dimensions of either ≈100 nm or in the micrometer range are compared. These larger ones exist as stack of graphene layers which is inspected with scanning electron microscopy. Both kinds of particles are then functionalized with either oxygen or fluorine. The size of the graphene particles is found to influence the degree of functionalization. Only the combination of XPS and HAXPES allows to detect the functionalization at the outermost surface of the particles or even of the stacks and to provide new insights into the functionalization process.
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.
The datasets from (Hard Energy) X-ray photoelectron spectroscopy, X-ray diffraction and Scanning Electron Microsopy are related to the publication
G. Chemello, X. Knigge, D. Ciornii, B.P. Reed, A.J. Pollard, C.A. Clifford, T. Howe, N. Vyas, V.-D. Hodoroaba, J. Radnik
"Influence of the morphology on the functionalization of graphene nanoplatelets analyzed by comparative photoelectron spectroscopy with soft and hard X-rays"
Advanced Materials Interfaces (2023), DOI: 10.1002/admi.202300116.
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.
Mesoporous glasses are a promising class of bioresorbable biomaterials characterized by high surface area and extended porosity in the range of 2 to 50 nm. These peculiar properties make them ideal materials for the controlled release of therapeutic ions and molecules. Whilst mesoporous silicate-based glasses (MSG) have been widely investigated, much less work has been done on mesoporous phosphate-based glasses (MPG). In the present study, MPG in the P2O5–CaO–Na2O system, undoped and doped with 1, 3, and 5 mol% of Cu ions were synthesized via a combination of the sol–gel method and supramolecular templating. The non-ionic triblock copolymer Pluronic P123 was used as a templating agent. The porous structure was studied via a combination of Scanning Electron Microscopy (SEM), Small-Angle X-ray Scattering (SAXS), and N2 adsorption–desorption analysis at 77 K. The structure of the phosphate network was investigated via solid state 31P Magic Angle Spinning Nuclear Magnetic Resonance (31P MAS-NMR) and Fourier Transform Infrared (FTIR) spectroscopy. Degradation studies, performed in water via Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), showed that phosphates, Ca2+, Na+ and Cu ions are released in a controlled manner over a 7 days period. The controlled release of Cu, proportional to the copper loading, imbues antibacterial properties to MPG. A significant statistical reduction of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacterial viability was observed over a 3 days period. E. coli appeared to be more resistant than S. aureus to the antibacterial effect of copper. This study shows that copper doped MPG have great potential as bioresorbable materials for controlled delivery of antibacterial ions.
This talk introduces the expanded view that comes from wide-range X-ray scattering investigations.
Compared to X-ray diffraction studies alone, the additional angular range of this technique provides information on the larger structural dimensions present in your samples. This allows for the extraction of information on the size and size distribution of nanostructural components, such as nanoparticles, nanovoids, and any other structure exhibiting an electron density contrast.
The talk introduces the technique, the MOUSE instrument used for these investigations, and provides several real-world examples of its uses. The audience is invited to choose which examples captures their interest from a range of options, in the latter segment of the talk.
Here a dataset of XPS, HAXPES and SEM measurements for the physico-chemical characterization of Au nanoparticles is presented. The measurements are part of the H2020 project “NanoSolveIT”.
Here a dataset of XPS, HAXPES and SEM measurements for the physico-chemical characterization of Fe3O4 nanoparticles is presented. The measurements are part of the H2020 project “NanoSolveIT”.
Interactions between a polymer and a substrate interface play a vital role in understanding the improvement in thin film material properties as well as serving as a model for nanocomposites. For any non-repulsive polymer-substrate interactions, polymer segments form an irreversibly adsorbed layer and show a slowdown in the glassy dynamics and thus an increase in the thermal glass transition temperature compared to the bulk-like values. The growth kinetics of the adsorbed layer obey a two-step mechanism: formation of immobilized layer with flat segmental conformations and a loosely bound layer with stretched chains pinned to the surface. Here the adsorbed layer was studied for: poly (bisphenol-A carbonate) (PBAC) and polysulfone (PSU), two bulky polymers containing a functional group (phenyl ring) in the backbone and compared to poly (2-vinyl pyridine) (P2VP), where the backbone is a vinyl-derivative and the functional group (pyridine) is in the side chain. The growth kinetics for PBAC and PSU were found to deviate from the well-known mechanism, observed for polymers such as P2VP. Atomic force microscopy and ellipsometry were used for this investigation and was additionally supported by broadband dielectric spectroscopy.
A few layer/multilayer graphene (MLG) with a specific surface area of BET ≥ 250 m2/g is proposed as an efficient multifunctional nanofiller for rubbers. The preparation method, i.e., ultrasonically-assisted solution or latex premixing of master batches followed by conventional two-roll milling, strongly influences the dispersion in the elastomeric matrix and is fundamental for the final properties. When homogenously dispersed, single stacks of only approximately 10 graphene sheets, with an aspect ratio of ca. 35, work at low loadings, enabling the replacement of large amounts of carbon black (CB), an increase in efficiency, and a reduction in filler load. The appropriate preparation yielded nanocomposites in which just 3 phr are sufficient to significantly improve the rheological, curing, gas barrier properties, electrical and thermal conductivity, as well as mechanical properties of different rubbers, as shown for chlorine-Isobutylene-Isoprene rubber (CIIR), nitrile-butadiene rubber (NBR), natural rubber (NR), and styrene-butadiene rubber (SBR).[1-5] 3 phr of MLG tripled the Young’s modulus of CIIR, an effect equivalent to 20 phr of CB. The stronger interactions between MLG and NR or SBR also resulted in a reduction in the elongation at break by 20% and 50%, respectively, while the same parameter was hardly changed for CIIR/MLG and NBR/MLG. CIIR/MLG and NBR/MLG were stiffer but just as defomable than CIIR and NBR. The strong reinforcing effect of 3 phr MLG was confirmed by the increase of greater than 10 Shore A in hardness. MLG reduces gas permeability, increases thermal and electrical conductivities, and retards flammability. We investigated MLG also as a synergist for reducing the aluminium trihydrate loading in flame retardant hydrogenated acrylonitrile-butadiene (HNBR), polybutadiene chloroprene (BR/CR), and chlorosulfonated polyethylene rubber(CSM).[6-8] The higher the nanofiller concentration is, the greater the improvement in the properties. For instance, the permeability decreased by 30% at 3 phr of MLG, 50% at 5 phr and 60% at 10 phr, respectively. Moreover, the MLG nanocomposites improve stability of mechanical properties against the effects of weathering. In key experiments an increase in UV-absorption and a pronounced radical scavenging were proved as stabilizing mechanisms. In a nutshell, MLG is an efficient multifunctional nanofiller ready to be used for innovative rubber development.
Comparative study of the co-assembly behaviour of 3-chloro-4-hydroxy-phenylazo dyes with DTAB
(2023)
The co-assembly of three one-fold negatively charged 3-chloro-4-hydroxy-phenylazo dyes (Yellow, Blue and Red) with the cationic surfactant dodecyltrimethylammoniumbromide (DTAB) was studied to probe dye–DTAB binding stoichiometry and assembly morphology. For each dye, phase separation was observed above a given dye : DTAB ratio with the ratio depending on the dye. While Yellow and DTAB showed liquid/liquid phase separation above Yellow : DTAB = 1 : 1.67, crystalline dye–DTAB complexes were observed for Blue–DTAB and Red–DTAB above Blue : DTAB = 1 : 2.56 and Red : DTAB = 1 : 2.94 respecively. In homogeneous solution, UV/vis spectroscopic investigations suggest stochiometries of Yellow : DTAB = 1 : 2, Blue : DTAB = 1 : 3 and Red : DTAB = 1 : 4. It was concluded, that Yellow exhibits the highest dye : DTAB binding stoichiometry in both, dye–surfactant complexes in the 2-phase region and in solution, whereas the lowest dye : DTAB binding stoichiometry was observed for Red–DTAB in both cases. The observed stoichiometries are inversely correlated to the impact dye addition has on the morphology of DTAB micelles. Generally, addition of dye to DTAB micelles leads to a reduction in spontaneous curvature of these micelles and to the formation of triaxial ellipsoidal or cylindrical micelles from oblate ellipsoidal DTAB micelles. At a DTAB concentration of 30 mM and a dye concentration of 5 mM, this effect was most pronounced for Red and least pronounced for Yellow, whilst Blue showed an intermediate effect.
X-ray photoelectron spectroscopy (XPS) is widely used for characterising the chemistry of graphene-related two-dimensional materials (GR2M), however the careful preparation of the sample for analysis is important in obtaining representative quantifications. We report an investigation by three laboratories showing that the preparation method for oxygen-functionalised graphene nanoplatelet (GNP) powders has a significant effect on the homogeneous-equivalent elemental composition measured in XPS. We show that pressing GNP powders onto adhesive tapes, into recesses, or into solid pellets results in inconsistencies in the XPS quantification. The measured oxygen-to-carbon atomic ratio from GNP pellets depends upon the die pressure used to form them and the morphology of the GNPs themselves. We recommend that powder samples of GR2Ms are pelletised prior to XPS analysis to improve repeatability and reproducibility of measurements.