abstract
A good and long-term stable electrical contact between the porous anode transport layer (PTL) and the adjacent catalyst layer is essential for efficient polymer electrolyte membrane water electrolyzers. This study describes the extensive comparison of seven titanium passivation-protecting coatings using short- and long-term measurements for at least 2000 h. The measurements are supported by before and after scanning electron microscope investigations of cross sections, energy-dispersive X-ray spectroscopy, X-ray diffractometry of the coatings, contact resistance measurements, and ex situ rapid aging tests. Overall, iridium and platinum PTL coatings offer outstanding contact and excellent corrosion protection. Compared to the uncoated reference sample, platinum shows a 93