Reference electrode measurements in electrolysis cells: an EIS view

Reference electrodes (REs) are a great tool to better understand processes in electrolysis cells at each electrode. By combining the use of REs with electrochemical impedance spectroscopy (EIS), we can analyse and assign overpotentials and degradation processes to specific electrodes. However, REs are tricky to place into a cell with a solid electrolyte and are subject to other constraints such as operation with pressurized gases and geometric clearance. Also, EIS measurements are easily affected by perturbations and noise which can lead to non-interpretable results. This is especially difficult when using reference electrode setups.

This webinar will give an intro on the usefulness of reference electrodes in different electrolysis applications, possible setups and exemplary use cases. We will then choose an exemplary setup for a PEMWE and present EIS results that show those perturbations and noises. Finally, we will propose a possibility to filter the signal and remove artefacts from the EIS results.

Ken Hansen and Lena Beuhre published a short communication on this topic during their postdoctoral research at NLR (formerly known as NREL). They both came with experience in reference electrodes (Beuhre in PEMWE, Hansen in CO₂RR) and EIS measurements. Besides these efforts, they collaborated in the H₂NEW consortium where they worked on anode catalyst development, degradation and for electrochemical characterization in segmented cells for PEMWE. While Hansen is now working in advanced diagnostic tools for CO/CO₂RR devices, Beuhre moved to Hannover where she is working as a junior research group leader for “Electrochemical Energy and Material Conversion” (habilitation candidate).