Dr. Claudia Cancellieri & Dr. Lars Jeurgens : Depth-Resolved Chemical and Electronic Structure of Surfaces and Interfaces by Combined Lab-Based XPS and HAXPES
Event details
| Date | 27.02.2026 |
| Hour | 14:30 › 15:30 |
| Speaker |
Dr. Claudia Cancellieri & Dr. Lars Jeurgens, Laboratory for Joining Technologies & Corrosion, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland |
| Location | Online |
| Category | Conferences - Seminars |
| Event Language | English |
Abstract : Hard X-ray photoelectron spectroscopy (HAXPES) provides access to photoelectrons with much higher kinetic energies than conventional XPS, which not only increases the probing depth but also gives access to an extended binding energy range for chemical state analysis. By combining XPS and HAXPES, specific core-level photoelectron lines can be measured at different probing depths and closely matched with the fixed probing depth of a corresponding Auger line. This enables chemical state analysis at near-constant probing depth by monitoring the so-called Auger parameter (AP), which is independent of charging and (electronic) band-banding effects [1].
This seminar presents a series of case studies illustrating the versatility of lab-based HAXPES in combination with conventional XPS for chemical state analysis across a broad range of functional materials used in corrosion protection, catalysis, nanojoining, diffusion barrier layers, energy materials, and solid-state battery technologies. For example, AP analysis of Al2O3 and TiO2 thin films prepared by different synthesis methods (e.g. atomic layer deposition (ALD), anodization, thermal oxidation) proves to be a powerful tool for tracing oxide polymorphism in the crystalline state, as well as tiny variations of the local coordination spheres between different amorphous states [2,3]. Changes in the local chemical states of the cations and anions in functional oxides, as evidenced from the measured AP shifts, can be correlated with variations in their optical and dielectric properties. Measured AP shifts of amorphous Al₂O₃ films with different densities and hydrogen contents (as grown by ALD) have been successfully predicted by atomistic simulations using machine-learning interatomic potentials [2, 3]. As such, the hydrogen-induced changes in the distribution of 4/5/6-fold local coordination spheres of the Al cations in the amorphous Al₂O₃ films could be disclosed [2,3]. Lab-based XPS/HAXPES has also been applied to develop procedures for efficient surface cleaning of Li₇La₃Zr₂O₁₂ solid electrolytes for solid-state batteries [4]. For metallic multilayers used in e.g. nano-joining technologies, measured AP shifts are shown to be a sensitive probe of electronic charge transfer at buried interfaces [5]. Very recently, an integrated electrochemical–UHV approach combined with dual-beam XPS/HAXPES has been implemented to study the interaction of atomic hydrogen with passive oxides on steels.
[1] S. Siol, et al., Concepts for chemical state analysis at constant probing depth by lab-based XPS/HAXPES combining soft and hard X-ray sources, Surface & Interface Analysis 52 (2020) 802.
[2] C. Cancellieri et al., Effect of Hydrogen on the Chemical State, Stoichiometry and Density of Amorphous Al2O3 Films Grown by Thermal Atomic Layer Deposition, Surface and Interface Analysis 56 (2024) 293.
[3] S. Gramatte et al., Unveiling hydrogen chemical states in supersaturated amorphous alumina via machine learning-driven atomistic modeling, npj Computational Materials 11 (2025) 170.
[4] H. Zhang et al., On high-temperature thermal cleaning of LLZO solid-state electrolytes, ACS Applied Energy Materials 6 (2023) 6972.
[5] C. Cancellieri et al., Chemical and Electronic Structure of Buried W/Cu, W/Cr, and W/Mo Interfaces by In Situ XPS/HAXPES Auger Parameter Analysis, Surface and Interface Analysis 57 (2025) 357.
Bio :
Dr. Claudia Cancellieri is a group leader/ research scientist at Empa in the Laboratory for Joining technologies and corrosion. In 2008 she obtained her PhD in Physics at École Polytechnique Federal in Lausanne (EPFL), specializing in Pulsed Laser Deposition growth of cuprates and oxide thin films under strain. During her first post-Doc at the University of Geneva, she focused on the growth and characterization of complex oxide interfaces. She continued the investigation of this topic at the synchrotron Swiss Light Source, Paul Scherrer Institute where she extensively used spectroscopy techniques to derive the electronic band structure of buried complex oxide interfaces. Her current research topics include the investigation of interfaces and their chemical stability in relation to microstructure, defects, internal stress and electronic properties of functional materials interfaces including multilayers systems and thin amorphous oxides on metals.
Dr. Lars Jeurgens obtained his PhD in materials sciences at the Delft University of Technology (NL) in 2001. After working for the Dutch technology foundation (STW), he moved to the Max Planck Institute for Metals Research in Stuttgart (DE) in 2003, leading a research group on “Reactions and Phase Transformations at Surfaces and Interfaces”, while being responsible for the surface analysis services at the institute. His research was honoured with the Masing Gedächtnispreis of the Deutsche Gesellschaft für Materialkunde (DGM) in 2008. Lars joined the Empa, as the head of the laboratory for “Joining Technologies and Corrosion”, in 2012. His research interests comprise the surface and interface engineering of metals, alloys, oxides and their coating systems for emerging nano-joining technologies and corrosion management, Since 2020, his laboratory runs the only lab-based Hard X-ray Photoelectron Spectrometer in Switzerland. Accordingly, his recent research focusses on chemical state studies of functional oxide films by combing soft and hard X-ray Photoelectron Spectroscopy
This seminar presents a series of case studies illustrating the versatility of lab-based HAXPES in combination with conventional XPS for chemical state analysis across a broad range of functional materials used in corrosion protection, catalysis, nanojoining, diffusion barrier layers, energy materials, and solid-state battery technologies. For example, AP analysis of Al2O3 and TiO2 thin films prepared by different synthesis methods (e.g. atomic layer deposition (ALD), anodization, thermal oxidation) proves to be a powerful tool for tracing oxide polymorphism in the crystalline state, as well as tiny variations of the local coordination spheres between different amorphous states [2,3]. Changes in the local chemical states of the cations and anions in functional oxides, as evidenced from the measured AP shifts, can be correlated with variations in their optical and dielectric properties. Measured AP shifts of amorphous Al₂O₃ films with different densities and hydrogen contents (as grown by ALD) have been successfully predicted by atomistic simulations using machine-learning interatomic potentials [2, 3]. As such, the hydrogen-induced changes in the distribution of 4/5/6-fold local coordination spheres of the Al cations in the amorphous Al₂O₃ films could be disclosed [2,3]. Lab-based XPS/HAXPES has also been applied to develop procedures for efficient surface cleaning of Li₇La₃Zr₂O₁₂ solid electrolytes for solid-state batteries [4]. For metallic multilayers used in e.g. nano-joining technologies, measured AP shifts are shown to be a sensitive probe of electronic charge transfer at buried interfaces [5]. Very recently, an integrated electrochemical–UHV approach combined with dual-beam XPS/HAXPES has been implemented to study the interaction of atomic hydrogen with passive oxides on steels.
[1] S. Siol, et al., Concepts for chemical state analysis at constant probing depth by lab-based XPS/HAXPES combining soft and hard X-ray sources, Surface & Interface Analysis 52 (2020) 802.
[2] C. Cancellieri et al., Effect of Hydrogen on the Chemical State, Stoichiometry and Density of Amorphous Al2O3 Films Grown by Thermal Atomic Layer Deposition, Surface and Interface Analysis 56 (2024) 293.
[3] S. Gramatte et al., Unveiling hydrogen chemical states in supersaturated amorphous alumina via machine learning-driven atomistic modeling, npj Computational Materials 11 (2025) 170.
[4] H. Zhang et al., On high-temperature thermal cleaning of LLZO solid-state electrolytes, ACS Applied Energy Materials 6 (2023) 6972.
[5] C. Cancellieri et al., Chemical and Electronic Structure of Buried W/Cu, W/Cr, and W/Mo Interfaces by In Situ XPS/HAXPES Auger Parameter Analysis, Surface and Interface Analysis 57 (2025) 357.
Bio :
Dr. Claudia Cancellieri is a group leader/ research scientist at Empa in the Laboratory for Joining technologies and corrosion. In 2008 she obtained her PhD in Physics at École Polytechnique Federal in Lausanne (EPFL), specializing in Pulsed Laser Deposition growth of cuprates and oxide thin films under strain. During her first post-Doc at the University of Geneva, she focused on the growth and characterization of complex oxide interfaces. She continued the investigation of this topic at the synchrotron Swiss Light Source, Paul Scherrer Institute where she extensively used spectroscopy techniques to derive the electronic band structure of buried complex oxide interfaces. Her current research topics include the investigation of interfaces and their chemical stability in relation to microstructure, defects, internal stress and electronic properties of functional materials interfaces including multilayers systems and thin amorphous oxides on metals.
Dr. Lars Jeurgens obtained his PhD in materials sciences at the Delft University of Technology (NL) in 2001. After working for the Dutch technology foundation (STW), he moved to the Max Planck Institute for Metals Research in Stuttgart (DE) in 2003, leading a research group on “Reactions and Phase Transformations at Surfaces and Interfaces”, while being responsible for the surface analysis services at the institute. His research was honoured with the Masing Gedächtnispreis of the Deutsche Gesellschaft für Materialkunde (DGM) in 2008. Lars joined the Empa, as the head of the laboratory for “Joining Technologies and Corrosion”, in 2012. His research interests comprise the surface and interface engineering of metals, alloys, oxides and their coating systems for emerging nano-joining technologies and corrosion management, Since 2020, his laboratory runs the only lab-based Hard X-ray Photoelectron Spectrometer in Switzerland. Accordingly, his recent research focusses on chemical state studies of functional oxide films by combing soft and hard X-ray Photoelectron Spectroscopy
Practical information
- Informed public
- Free
Organizer
- Institute of Chemical Sciences and Engineering
Contact
- Wendy Queen
[email protected]