Polymer electrolyte membrane water electrolyzers (PEMWE) are clean and scalable energy conversion devices that can assist with electricity peak shaving and storage by converting electricity into hydrogen as an energy carrier ¹. However, performance, durability and cost of these systems still require further improvements before they can be widely adopted. In particular, it is desired to have more efficient and lower cost oxygen evolution reaction (OER) electrocatalysts for the anode, because of the high cost and potential losses that are associated with this electrode². Screening of catalyst materials, as well other expensive cell components (e.g., Ti current collectors and Ti endplates), is in general a slow and rather expensive process due to the inherent high costs of test cell equipment, and the difficulties associated with cell assembly³. Alternative methods based on commonly available and small laboratory-scale electrochemical test equipment, such as the rotating disk electrode, can facilitate the screening process.

We present a novel and economical method for testing electrolysis CCMs and potential current collectors in a rotating electrode (RDE) setup. This method eliminates the difficulties which are often associated with ink preparation and sample drying which are encountered in thin film RDE (TF-RDE) testing. Very recently, we have successfully demonstrated this approach for evaluation of oxygen reduction reaction (ORR) electrocatalysts used in PEMFC applications⁴. The modified-RDE (MRDE) presented here allows a user to obtain very high current densities (~ 2 A cm^-2) which is similar to those normally obtained with PEMWE hardware and test stations (Figure 1). Polarization measurements, kinetic analysis and accelerated degradation tests (ADT) have been performed with a commercial IrO₂-based CCM using the MRDE, and are compared with those of PEMWE hardware results. The approach, methodology and the results will be presented at the meeting.

References:

1. A. S. Aricò, S. Siracusano, N. Briguglio, V. Baglio, A. Di Blasi, and V. Antonucci, J. Appl. Electrochem., 43, 107–118 (2013).
2. H. Dau, C. Limberg, T. Reier, M. Risch, S. Roggan, and P. Strasser, ChemCatChem, 2, 724–761 (2010).
3. A. S. Lohoff, L. Poggemann, M. Carmo, M. Müller, and D. Stolten, J. Electrochem. Soc., 163, F3153–F3157 (2016) http://jes.ecsdl.org/lookup/doi/10.1149/2.0211611jes.
4. J. T. H. Kwan, A. Bonakdarpour, G. Afonso, and D. P. Wilkinson, Electrochim. Acta, 258, 208–219 (2017) http://linkinghub.elsevier.com/retrieve/pii/S0013468617322090.

Figure 1: The effect of different titanium current collector meshes on OER performance using a commercial IrO₂-based CCM obtained by the MRDE tool. Inset shows pictures of the different Ti meshes examined.