Electrocatalysis Strategy

Challenges

• Conversion of H₂O and CO₂ with high energy efficiency
• Selective formation of fuels and value-added chemicals: H₂, hydrocarbons, alcohols, …
• Long-term catalyst stability

Approach

• Study catalysts in operation (operando/in situ) by spectros-, microscopy, diffraction
• New cross-disciplinary experimental approaches
• Strong interaction with computational modeling

Task Leaders & Team

Principal Investigators and links to their websites

Jürgen Fleig: electrochemistry of solids (solid-state ionics) with emphasis on ionic/electronic defects, their transport, and reaction at surfaces. He uses multiple electrochemical /analytical tools for mechanistic studies and works on fundamental kinetic concepts related to electrochemical cells.

PhD1 will focus on the transport properties of oxide ions and protons in perovskite-type oxides at low temperatures (also in contact with water) and PhD2 will use surface analytical tools for correlating the electrochemical reactivity in solid state and aqueous electrochemical cells and the oxide surface chemistry. The Postdoc will broadly extend defect chemical investigations of common oxides to low temperatures, will combine solid-state cells and aqueous cells (with a common electrode) and will analyze the mutual polarization-dependent interactions of the cells.

Stefan Freunberger: redox chemistry of main group compounds (O, S, N, organics, halogens) related to energy storage/conversion. He elucidates reaction mechanisms with respect to chemistry, dynamics, and structural evolution at bulk and interfaces.

Jani Kotakoski: structural study and manipulation of 2D materials and their defects. His expertise includes atomic-resolution transmission electron microscopy, in situ techniques, and machine-learning-based analysis tools for atomistic simulations.

The Kotakoski research group is looking for a postdoc with experience in atomic-resolution scanning transmission electron microscopy (STEM), defect-engineering of 2D materials and physical vapour deposition. Experience with in-situ microscopy techniques is an advantage. The group is further looking for two PhD students. One doctoral project concentrates on defect-engineering of 2D materials, whereas the other one focuses on the growth of metallic nanostructures (clusters and/or islands) on 2D materials. All positions will involve state-of-the-art 4D STEM imaging techniques, high-energy resolution electron energy loss spectroscopy and in situ catalysis experiments with a new unique microscope that will be installed within the first two years of the project. The research projects will also include characterization of materials from other research groups within MECS, and direct collaboration, for example, on catalysis measurements.

Julia Kunze-Liebhäuser: combines electrochemistry with in situ analytics to identify interface morphology, structure and chemistry, and the nature of intermediates/products under operating conditions. She conducts fundamental electrocatalysis studies of metal single-crystals and compound materials.

For a rapid project start, the PD will prepare (chemical deposition) and characterize (SEM, XPS, SPM) the structured bimetallic and transition metal hydroxide covered single- and polycrystalline electrodes. Electrochemical activities towards HER and CO(2)RR will be examined. Ph.D. 1 continues the electrochemistry and starts DEMS studies, Ph.D. 2 will focus on in situ EC-STM and EC-IR.

Alexander Opitz: solid-state electrochemistry with a focus on in situ studying the surface chemistry of mixed conducting electrode materials. He combines electrochemical and surface analytical methods to reveal the mechanistic interplay of point defects and surface species.

PhD1 will develop novel materials for high-temperature CO₂ reduction in oxide ion conducting cells, and PhD2 will focus on employing proton-conducting electrode materials for hydrogenation of CO₂ , CO, and N₂. The PostDoc is responsible for performing the in-situ analytical studies on both material classes (i.e. building the bridge to the surface analytical groups), and for upscaling the model systems to demonstrate the material properties also on an application near level.

Christoph Rameshan: heterogeneous catalysis, with a focus on in situ or operando spectroscopies on model systems. He strives to understand the correlation between catalyst structure/composition and reactivity.

A PD with experience in material synthesis and in-situ characterisation will focus on the fabrication of the new bimetallic nanoparticles. One PhD will then focus on the heterogeneous catalytic testing for CO₂ activation including in-situ spectroscopy and the second PhD will focus on the electrocatalytic CO₂ reduction on the novel materials.

Günther Rupprechter: heterogeneous model catalysis. Early on, he has developed and applied lab- and synchrotron-based in situ or operando spectroscopy and microscopy of catalytic reactions on single crystals, thin films, and supported nanoparticles, often carried out in lockstep with modeling.

The Rupprechter research group is looking for a postdoc and 2 PhDs with experience in either surface science, heterogeneous catalysis, modeling, spectroscopy and/or microscopy. For a rapid project start, an experienced Postdoctoral Researcher will prepare structured bimetallic and perovskite electrode assemblies via lithography methods. The surfaces will be characterized by UV and X-PEEM, SPEM, and LEEM, including both lab- and synchrotron-based equipment. PhD1 will assist and continue these activities, while PhD2 will focus on in situ PM-IRAS/NAP-XPS/-UPS/SXRD studies of corresponding homogeneous layers. The project benefits from unique equipment, a dedicated training program and close collaborations with other research groups within MECS.

Markus Valtiner: electrochemical solid/liquid interfaces. He has developed in situ tools for characterizing electric double layers and reaction dynamics at confined and non-confined interfaces. Single-molecule thermodynamics at solid/liquid interfaces, and imaging of degradation of oxides and metals.

One PhD student, working as part of Pillar A, will focus on correlating surface analytics with in situ degradation of catalysts with electrochemical flow cells coupled to ICP-MS analysis using single crystal facettes and complex alloys. A second PhD/ or PD will work on in situ visualization by EC-AFM and interferometry and will construct and use quasi in situ couplings to surface sensitive spectroscopies (XPS, AES, LEIS) for quantifying surface/solute interactions. A second PhD/ or PD will complement this work using simulations and modelling, interacting with Pillar C and theoreticians in Pillar A.