The corrosion behavior of TA1 and TC4 in Proton Exchange Membrane Water Electrolyzers

Abstract

Titanium Bipolar Plates (BPPs) are frequently utilized in Proton Exchange Membrane Water Electrolyzers (PEMWE) nowadays since they could endure the challenging working environment. Notably, the extreme anodic potential and acidic environment of the PEMWE are extremely critical for BPPs’ performances. In this study, we explored the corrosion behaviors of conventional titanium alloys of TA1 and Ti-6Al-4V (TC4) at simulated operating conditions. To evaluate their corrosion behaviors, potentiodynamic polarization, electrochemical impedance spectroscopy, and potentiation, polarization experiments were executed. Additionally, scanning electron microscopy (SEM) was applied to detect the morphologies before and after the electrochemical measurements. Finally, the corrosion mechanisms of TA1 and TC4 were analyzed and discussed by X-ray photoelectron spectroscopy (XPS). After 7 days of potentiostatic polarization, the corrosion current density of TA1 remained at 3×10−8 A·cm−2, which was nearly one order of magnitude lower than that of TC4. These experimental data confirmed that the TA1 alloy had superior corrosion resistance to the TC4 alloy during long-term running in PEMWE operating conditions.