Degradation studies of proton exchange membrane water electrolysis cells with low platinum group metals – Catalyst coating achieved by atomic layer deposition

Activity and durability of a polymer electrolyte membrane (PEM) water electrolysis single cell, assembled with porous transport electrodes (PTEs) with a low catalyst loading were investigated for 500 h. A current density of 160 mA/cm2 and a high mass activity of 1368 A/gIr were achieved while operating at 60 °C with 1 mol/L sulfuric acid. The degradation of the cell was characterized using different electrochemical and physicochemical methods before, during and after operation of the electrolysis cell and a mean degradation rate for the cell of 67 μV/h was determined at 15 mA/cm2. To the best of our knowledge this is the first time that long-term performance of a PEM water electrolysis cell assembled with PTEs coated by ALD is investigated.