Postdoctoral Position - Spectro-Microscopy Studies of Complex Processes in Thermal Catalysis

Postdoctoral Position - Spectro-Microscopy Studies of Complex Processes in Thermal Catalysis

Fritz Haber Institute of the Max Planck Society

Berlin, Germany

The Department of Interface Science, headed by Prof. Beatriz Roldán Cuenya at the Fritz Haber Institute, carries out cutting-edge research on advanced functional materials with applications in heterogeneous catalysis, energy conversion and electrochemistry. By combining unique synthesis methods, state-of-the-art tools for experimental characterization and advanced approaches to data analysis, atomistic details of thermal catalysis and electrochemical reactions at gas/solid and liquid/solid interfaces are revealed. In particular, structure-reactivity correlations on nanostructured materials can be established, paving the way for the rational design of novel catalytic materials.

The Spectro-Microscopy group operates an ultra-high vacuum (UHV) based aberrations corrected and energy filtered Low Energy and Photoemission Electron Microscopy (LEEM/PEEM) at the UE49PGM-SMART high flux soft x-ray beamline at BESSY-II. This spectro-microscope is used to characterize catalytically active surfaces such as single crystal surfaces, oxide films and supported nanoparticles (NP) and to follow in real time and in situ processes such as epitaxial film growth, thermal reactions in a pressure range up to 10-5 mbar and phase transitions. Various special equipment is connected to the microscope allowing for quasi in situ processes like UHV-based plasma treatment, chemical reactions in near ambient pressure (NAP) and electrochemistry. The instrument excels at (1) the comprehensive characterization by combining various microscopy, diffraction and spectroscopy tools at high lateral and energy resolution of up to 2.6 nm and 180 meV, respectively, (2) high and tunable surface sensitivity between 0.3 and 3 nm, (3) high chemical sensitivity (elemental composition, chemical state) and structural sensitivity (surface reconstruction of absorbed species, crystallinity, surface facet orientation) and (4) fast acquisition of the full field image (higher than video rate). Furthermore, the group operates a pure LEEM/PEEM microscope which is equipped with a high-pressure cell (HPC) to quasi in situ study chemical reactions on catalytically active surfaces with reactive gases in a pressure range up to 20 bar. The third instrument is a unique NAP-LEEM/XPEEM, which is dedicated to observing in real time thermal reactions in the mbar range.

The field of scientific interest covers thermal catalysis as well as electrochemistry. Reactions under investigation have been CO2 hydrogenation, CO2RR, dry methane reforming, OER and ammonia synthesis. As catalysts, we use well-defined single crystal surfaces with different orientations or thin oxide films grown on single crystals as model systems, which can be modified, e.g., by plasma treatments, controlled miscuts or additionally deposited materials to tune the reactivity and selectivity. Additionally, polycrystalline samples and supported nanoparticles have been used as a catalyst. Typical materials have been Cu, Ni, Fe, Ag, Pd, SiO2 and Co oxide.

The selected candidate can choose to pursue their main project in either thermal catalysis or electrocatalysis. Besides the main project, the candidate is expected to work in a team on diverse projects from collaborations (within the ISC Department projects), and also to support the experiments of the external users at the SMART beamline. Your challenge will be to improvise the methodologies of measurements and analysis towards various samples and reactions following an initial training of the spectro-microscope.

Requirements

• A PhD degree in Chemistry, Physics or Physical Chemistry, preferably with a specialization in electrochemistry, thermal catalysis or surface science;
• A strong publication record in renowned peer-reviewed journals;
• Knowledge about surface science techniques like e.g. XPS, NEXAFS, LEED, PEEM, LEEM, TDS;
• Experience at performing complex UHV or electrochemistry experiments with a high drive to solve scientific and practical/instrumental challenges independently;
• Experience working at synchrotron light sources (preferred, but not required);
• Ability to work in a team;
• Collaborative spirit and excellent English skills.