Corrosion behavior of TiZrNbC coatings on TA1 substrates in simulated PEM water electrolysis

A TiZrNbC coating was deposited on the TA1 substrate by magnetron sputtering technology, and the corrosion behaviors of the TiZrNbC coating in a simulated proton exchange membrane water electrolysis (PEMWE) environment under fluctuating potentials were investigated. The microstructures and elemental distributions of the coating were characterized by SEM and EDS. The PEMWE environment was simulated using a dilute H₂SO₄ solution with pH = 3 and a 5 ppm of fluoride (F^-) ions addition, and polarization tests were conducted under the potentials with constant, square and triangular waveforms. The corrosion resistances of the TiZrNbC-coated and bare TA1 substrates were characterized by potentiodynamic polarization, electrochemical impedance spectroscopy and interfacial contact resistance tests. Compared to the bare TA1 substrates, the TiZrNbC-coated TA1 substrates exhibited lower corrosion current densities, higher polarization resistances and lower contact resistances, demonstrating a superior corrosion resistance.