%0 Conference Paper
%A Erkes, Rebecca
%T Nanomaterials - Synthesis and Characterization
%I RWTH Aachen
%M FZJ-2026-00480
%D 2025
%X Nanomaterials (NMs) are defined by their characteristic dimensions on the nanoscale (1 – 100 nm), a size regime where unique surface and quantum effects emerge. They can be catego-rized by their external dimensions into 4 categories: 0D-materials (nanoparticles, quantum dots), 1D-materials (nanorods, nanotubes), 2D-materials (graphene, nanosheets) or 3D-materials (foams, aggregates). These material classes share novel size-dependent properties absent in their bulk-counterparts, such as the drastically increased surface-to-volume ratio. This leads to more active sites on the surface, enhancing chemical reactivity and catalytic activity, for exam-ple in Pt catalyst particles. Quantum confinement effects induce size-dependent quantization of electronic and optical properties, such as the emergence of magnetism in Au, Pt or Pd nanoparti-cles, despite their bulk counterparts lacking any magnetic behavior. Due to the high fraction of surface atoms, the surface energy of nanomaterials is reduced significantly, leading to e.g. a de-crease in melting point (e.g. 5 nm Au particles melt ~400 °C below bulk gold). These novel properties drive the intensive exploration of NMs in synthesis and characterization research and fuel their application in various fields, like catalysis, electronics, biomedicine, and energy con-version.Countless precise synthesis strategies have been developed to control the size, shape, composi-tion, and surface chemistry of NMs, thereby tuning their properties. These methods fall into two broad categories: top-down routes that fracture or pattern bulk materials, and bottom-up strate-gies, that assemble nanomaterials from atoms or molecules. Most frequently, top-down strategies employ mechanical milling techniques, such as high-energy ball milling. Here bulk solids are reduced to sizes of 10 – 200 nm, producing nanocrys-talline powders. Though prolonged milling can produce even smaller particle sizes, it simultane-ously causes contamination from media abrasion. Additionally, size and shape control are rather limited with such techniques.Bottom-up methods offer more precise shape and size control. In sol-gel processing, hydrolysis and polycondensation transform the dissolved metal alkoxide precursor (sol) into complex oxide networks (gel). With subsequent aging and calcination, metal oxide particles, powders, fibers, or films can be obtained. Hydro- and solvothermal synthesis routes produce uniform crystals of diverse shapes in the range or 10 – 500 nm by superheating solutions in a sealed vessel. After this controlled crystal growth, nanomaterial suspensions are yielded, that can then be further processed The optimal synthesis route and conditions are usually chosen with regard to the material requirements posed by the individual application area. Correlative characterization is crucial to link NMs structure to their functional properties. Trans-mission (TEM) and scanning electron microscopy (SEM) provide high-resolution imaging of NM shape, size, size distribution and lattice structure at the atomic scale. Small angle X-ray or neutron scattering (SAXS/SANS) non-destructively resolve size-shape and surface-area infor-mation by analyzing low-angle intensity profiles. Since these techniques average information over particle ensembles, they complement localized microscopy methods well, confirming mor-phologies and highlighting polydispersity.Engineering advanced NMs for electrochemical applications demands integrated strategies. By selecting appropriate top-down or bottom-up approaches and applying targeted analytical tools, materials with specifically optimized structural, chemical and functional properties can be tai-lored to meet the requirements of batteries, electrolyzers, and other electrochemical systems.
%B IET-1 EC-Days 2025
%C 1 Sep 2025 - 2 Sep 2025, Eindhoven (Netherlands)
Y2 1 Sep 2025 - 2 Sep 2025
M2 Eindhoven, Netherlands
%F PUB:(DE-HGF)31
%9 Talk (non-conference)
%U https://juser.fz-juelich.de/record/1050737