FOR 2397:  Multi-scale analysis of complex three-phase systems

• Subject Area: Thermal Engineering/Process Engineering ; Chemistry
• Term: since 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 276655287

Gas-diffusion electrodes (GDE) are key components for several relevant electrochemical processes such as fuel cells, metal-air batteries and electrolysis processes with fundamental importance for the energy turnaround. In the research unit, the oxygen reduction and the CO2 electrolysis over silver-based GDE in aqueous electrolyte shall be studied as examples. The preparation methods for these GDE must ensure high electro-catalytic activity, low electronic resistance as well as high chemical and mechanical stability. The morphology of the GDE pore system plays a decisive role for these requirements, since only a proper combination of hydrophilic and hydrophobic properties gives rise to intimate contact between liquid electrolyte, gaseous reactants and the electro-catalyst. A detailed description of GDE has only been partially possible up to now. This is due to the complex interplay of processes, missing methods for spatially resolved in situ and in operando observations using working GDE, and the limited availability of models with sound physico-chemical basis. The research unit shall combine competencies in the fields of electrode preparation, tomography, modeling of phase distribution and transport, micro-electrochemistry as well as analysis and modeling of micro- and macro-kinetics on all relevant scales. Thus, the complex interaction of transport and reaction processes can be understood and quantitatively described. In the proposed coordination project, the necessary resources for the general support measures within the group as well as for electrode preparation and manufacture of half cells for all partners are requested.

• DFG Programme: Research Units

Projects

• 3D structure-property relationships and operando imaging of the electrolyte distribution (Applicant Manke, Ingo )
• Central subproject: Preparation and characterization of technical silver electrodes (Applicant Turek, Thomas )
• Coordination Funds (Applicant Turek, Thomas )
• Dynamic state analysis of porous gas diffusion electrodes (Applicant Krewer, Ulrike )
• Fabrication and characterization of tailored electrodes as model systems (Applicant Roth, Christina )
• Miikroelectrochemical investigation of the oxygen and CO2 reduction at gas diffusion electrodes (Applicant Schuhmann, Wolfgang )
• Model-based Analysis of Oxygen and CO2 Reduction Reaction Kinetics on Silver Electrodes (Applicant Vidakovic-Koch, Tanja )
• Modeling of the electrolyte distribution in representative volumes (Applicant Nieken, Ulrich )
• Steady-state modeling of overvoltage on Ag-GDE during reduction reactions in aqueous electrolyte (Applicant Turek, Thomas )

• Spokesperson: Professor Dr.-Ing. Thomas Turek