Nanostructured interfaces
In batteries and electrolytes, in fuel cells, in heterogeneous catalysis and in nanotechnology itself - nanostructured interfaces are the source of material functionality in a wide range of applications. Each interface represents a deviation from the bulk structure of the material and restructuring occurs on both sides of the interfaces, typically over three to five atomic or molecular layers. This restructuring also changes the physicochemical properties of the interface compared to the bulk material. We need to understand these interfaces better in order to control and optimise material properties and applications.
We use various scattering methods to characterise nanostructured interfaces, including complementary powder diffraction and the pair distribution function (PDF) method for the characterisation of short- and long-range (dis)order. We use it to perform in-situ and operando experiments, often multimodally coupled with in-situ mass spectrometry (MS) or diffuse reflectance infrared spectroscopy (DRIFTS), to investigate structure-activity relationships of, for example, heterogeneous catalysts, or to track nanoparticle growth and sintering during electrochemical cycling or catalysis. Small angle scattering (SAXS / SANS) is often used to complement this.
To investigate dynamic processes such as the diffusion of ions/protons and molecules through materials or on surfaces, we use neutron spectroscopy, e.g. quasielatic neutron scattering (QENS). With QENS it is possible to follow the diffusion dynamics of lithium ions through battery materials, proton dynamics in proton conductors or the diffusion of water molecules around proteins and on nanoparticle surfaces, and to investigate the activation energy, the geometry of the motion and the diffusion constants.
Contact:
Publications:
Quasielastic Neutron Scattering of Citrate-Capped Iron Oxide Nanoparticles: Distinguishing Between Ligand, Water, and Magnetic Dynamics, M. S. Plekhanov, S. L. J. Thomä, A. Magerl, M. Appel, M. Zobel*, J. Phys. Chem. C.128 (2024), 28, 11661–11671, doi: 10.1021/acs.jpcc.4c00479. *Cover Image*
Neutron Diffraction - A Primer
R. Dronskowski, T. Brückel, H. Kohlmann, M. Avdeev, A. Houben, M. Meven, M. Hofmann, T. Kamiyama, M. Zobel, W. Schweika, R. P. Hermann, A. Sano-Furukawa, Z. Kristallogr. 239 (5–6) (2024),139–166, doi: 10.1515/zkri-2024-0001
H-D-isotope effect of heavy water affecting ligand-mediated nanoparticle formation in SANS and NMR experiments,
S. W. Krauss, M. Eckardt, J. Will, E. Spiecker, R. Siegel, M. Dulle, R. Schweins, B. Pauw, J. Senker, M. Zobel*,
Nanoscale 15 (2023), 16413-16424, doi: 10.1039/d3nr02419a