As PEM water electrolysis becomes a core technology for large-scale green hydrogen production, the durability of its structural materials has emerged as a decisive factor for long-term system performance. Operating under high voltage, acidic media, and strongly oxidizing conditions, PEM electrolyzers place exceptional demands on components such as bipolar plates and porous transport layers. In this context, titanium alloys have proven to be a critical and reliable material choice.
Outstanding Corrosion Resistance in Harsh Electrochemical Environments
Titanium alloys naturally form a dense and chemically stable oxide layer on the surface when exposed to oxidizing conditions. This passive film effectively isolates the base metal from corrosive electrolytes, ensuring long-term resistance in acidic and high-potential environments. Even if the surface is locally damaged, the oxide layer can rapidly regenerate, maintaining stable protection throughout extended operating cycles. This self-protecting behavior is a key reason titanium outperforms many alternative metallic materials in PEM electrolyzers.
Mechanical Strength and Functional Stability under Pressure
PEM electrolyzer stacks typically operate under internal pressures of several megapascals, requiring bipolar plates to maintain dimensional stability while enabling uniform gas distribution and current flow. Titanium alloys combine high specific strength with low density, supporting compact, lightweight system designs without compromising structural integrity. Their electrical properties also contribute to lower contact resistance, helping improve overall electrolyzer efficiency
High-purity titanium minimizes the release of metal ions that could degrade proton exchange membranes or poison noble metal catalysts. This purity plays an important role in preserving electrochemical performance and extending stack lifetime, particularly in systems designed for continuous, long-duration operation.
Recent large-scale green hydrogen projects in China have demonstrated the successful application of domestically developed titanium materials in PEM electrolyzers, confirming their readiness for commercial deployment. While titanium components often remain hidden within the stack, they serve as a fundamental safeguard-supporting stable operation, protecting investment value, and enabling the scalable future of PEM-based green hydrogen production.
