Investigation of Performance Losses in PEM Electrolyzer

Abstract

Polymer electrolyte membrane water electrolyzers (PEMWE) are playing an increasingly important role in hydrogen production for clean energy deployment.1 , 2 Yet hydrogen production through water electrolysis remains a niche application due to the high capital and operating expenses driven by the cost and low durability of the catalysts. The oxygen evolution reaction (OER) on the anode is particularly challenging due to the high operating potentials required to achieve high current densities, and is also responsible for rapid degradation and performance loss.3 In this work, durability tests of the anode catalyst layer were designed and carried out to reveal the catalyst degradation pathways. Iridium dissolution from the catalyst layer at high operating potential, porosity loss and thinning of the catalyst layer were investigated with our design. Previously developed testing protocols for Accelerated Stress Test (AST) measurements were applied to the electrolyzer to mimic the dynamic operation conditions and to accelerate the degradation rate.1 The effect of catalyst layer parameters like ionomer loading in the catalyst layers, the nature of the catalysts, membrane, and the fabrication techniques on anode catalyst durability were systematically evaluated and will be reported.4 Acknowledgement This research is supported by the U.S. Department of Energy (DOE) Hydrogen and Fuel Cell Technologies Office, through the H2NEW consortium.References S. M. Alia, S. Stariha, and R. L. Borup, J. Electrochem. Soc., 166, F1164–F1172 (2019).M. Carmo, D. L. Fritz, J. Mergel, and D. Stolten, Int. J. Hydrogen Energy, 38, 4901–4934 (2013).C. Lee, J. K. Lee, B. Zhao, K. F. Fahy, and A. Bazylak, J. Electrochem. Soc., 167, 024508 (2020) http://dx.doi.org/10.1149/1945-7111/ab68c8.S. M. Alia, K. S. Reeves, J. S. Baxter, and D. A. Cullen, J. Electrochem. Soc., 167, 144512 (2020).