X-ray characterization of materials (cam-X): Zooming into hierarchical materials

Investigating the underlying structure of material in order to understand, predict and improve its properties is a central element of material science research. The relevant length scales can span from many meters down to the molecular organization at the Ångström level, thus making characterization tools capable of surmounting multiple length scales important.  X-ray based techniques offer great benefits due to combining high penetration depths with information on the structural arrangement through their interaction with  materials down to the nanoscale. One example is small- and wide-angle X-ray scattering (SAXS/WAXS) which can be combined with focused synchrotron radiation turning it into an imaging method, providing information on the building blocks over macroscopic length scales, such as millimeter or centimeters. One key component of our research is to investigate materials where alignment of the building units confers anisotropic properties to the materials. Combining X-ray scattering with computed-tomography while extracting local three-dimensional orientation information allows to study the arrangement in complex matter. A well suited example from biology  is bone tissue, where the mineralized collagen fibers are arranged in a way to optimize the structural support with efficient material usage. Synthetic materials can also exhibit anisotropic material properties, if for example polymer chains are aligned within the processing steps. In-situ measurements allow to deepen our understanding of the processing step in order to obtain an improved control over the manufacturing process and thereby tailored materials properties.
Bio: Marianne Liebi is Tenure-Track Assistant Professor at EPF Lausanne, heading the Laboratory for X-ray characterization of materials (cam-X) and Group Leader at the Paul Scherrer Institute (PSI). She has been appointed in 2021 at EPFL where she is part of the Institute of Materials within the School of Engineering. Marianne Liebi studied Food Science at ETH Zurich where she also obtained her PhD in 2013. As a Postdoc in the coherent X-ray scattering group at the Swiss Light Source she worked from 2013-2016 on method development in SAXS tensor tomography. In 2016 she moved to Sweden where after a short period at the NanoMAX beamline, MAXIV Laboratory, Lund she started her own research group in 2017 as Assistant Professor at the Chalmers University of Technology, Gothenburg, and became Docent in Physics in spring 2020. She kept her affiliation at Chalmers University of Technology, where still part of her group is located when moving back to Switzerland in 2020 where she was Scientific Group Leader in the Center for X-ray Analytics at Empa, St.Gallen, before joining PSI and EPFL in November 2021.