In brief
The disruptiveGDE project is developing innovative gas diffusion electrodes for CO₂ electrolysis in organic electrolytes. 3D metallic mesh structures enable the creation of a boundary layer – free of PFAS – that can be controlled solely by the applied pressure. The method prevents excessive hydrogen formation, enables high current densities and long operating times, and facilitates the targeted synthesis of higher-value molecules.
What we’re working on
Motivation
The conventional route for producing valuable chemicals from CO₂ is a multi-stage process involving hydrogen production followed by CO₂ hydrogenation. In contrast, organic electrosynthesis combines several process steps, thereby enabling the direct conversion of CO₂ into valuable end products. This electrolysis process therefore has the potential to replace the conventional route in an energy-efficient manner.
Innovative approach
disruptiveGDE is developing a new concept for gas diffusion electrodes (GDE) that are also suitable for organic solvents and do not require PFAS materials. Instead of conventional GDEs, permeable metallic structures are used, in which the gas–liquid interface is precisely controlled via the pressure difference between the gas and liquid phases. This Laplace pressure-controlled design enables a stable supply of CO₂ to the reactor and opens up new degrees of freedom for electrolyser operation.
Implementation and added value
The project investigates suitable cell configurations for continuous operation, reference electrode concepts for organic electrolytes, and the key transport and reaction processes. The results are demonstrated using the synthesis of oxalic acid, cyanoacetic acid and adipic acid as examples. The combination of experiments and simulation provides a basis for techno-economic and environmental assessments, an important step towards industrial CO₂ electrosynthesis.
disruptiveGDE in figures
Material from the project
Chair of Power-to-X Technologies
Prof. Etzold’s research group is intensively engaged with the complex interplay between catalytic materials and mass transfer effects in electrochemical and heterogeneous catalytic systems. A particular focus is on the development and testing of catalysts and gas diffusion electrodes, as well as on reproducible experimental methods for electrolysis and flow cell systems. In disruptiveGDE, both the deposition of catalytic layers on metallic meshes and continuous flow experiments are carried out, and methods for visualising the gas-liquid interface in Laplace-pressure-controlled gas diffusion electrodes are being developed.
Gaskatel GmbH is an SME specialising in electrochemical technologies for analytical instruments. For over 25 years, Gaskatel has offered a wide range of electrodes, measuring cells and gas diffusion electrodes for aqueous electrolytes, such as those used in fuel cells, electrolysers and batteries. Gaskatel is contributing this expertise to disruptiveGDE and applying it to organic electrochemistry. This creates an industrial perspective to support the transfer to scalable and application-oriented systems.
The Institute for Applied Materials – Electrochemical Technologies (IAM-ET) at KIT combines experimental investigations of electrochemical CO₂ reactions with physico-chemical modelling to develop a sound understanding of the processes involved. A key focus is on the structural characterisation of gas diffusion electrodes to derive structure-property relationships. Within disruptiveGDE, Dr Röse’s junior research group contributes expertise in electroorganic chemistry and, through reaction elucidation and model-based analyses, contributes to the kinetic description and the techno-economic optimisation of the process design.
In the Nano- and Microfluidics Group at TU Darmstadt, fundamental transport phenomena at the micro- and nanoscale are investigated using detailed numerical simulations and experiments. This yields a deep understanding of the fluid dynamic processes in gas diffusion electrodes, which forms the basis for the efficient computer-aided design of electrode geometries and process parameters.
Contact
Prof. Bastian J. M. Etzold
Friedrich-Alexander University of Erlangen-Nuremberg
bastian.etzold@fau.de