Proton Exchange Membrane (PEM) electrolyzers are widely recognized as an efficient, modular, and environmentally friendly solution for green hydrogen production. Operating in harsh conditions, including strong acidic environments, high current densities, and elevated temperatures, PEM electrolyzers place high demands on the materials used for core components. Titanium and its alloys, with excellent corrosion resistance and good electrical conductivity, have become the preferred choice for these critical parts.
1. Critical Components Using Titanium
Anode Plates and Current Collectors
Anode plates and current collectors must endure highly oxidative conditions while providing low-resistance pathways for electricity. Titanium plates or titanium-coated metals are commonly used as anode substrates due to their chemical stability and excellent oxidation resistance. To enhance electrolysis efficiency and long-term reliability, a thin layer of iridium or platinum catalyst is often deposited on the surface.
Gas Diffusion Layers (GDLs)
The gas diffusion layer plays a vital role in evenly distributing water and oxygen while removing gas bubbles generated during electrolysis. Titanium mesh or wire mesh is widely used because it provides mechanical support and conductivity, while its corrosion-resistant nature significantly extends the service life. Mesh designs typically feature openings of 0.5–2 mm and 40–70% porosity, striking a balance between fluid flow and structural strength.
Fluid Contact Components and Structural Supports
Pipes, brackets, and other components in direct contact with the electrolyte must resist both corrosion and high temperatures. Titanium rods, pipes, and supports are ideal for these purposes, preventing degradation and ensuring structural stability for long-term operation.
Electrode Substrates and Cathode Protection
Titanium plates or mesh are often used as electrode substrates to support precious metal catalyst layers. Surface treatments can enhance catalyst adhesion and improve electrolysis efficiency. Additionally, titanium-coated metals are used for cathode protection and housing corrosion resistance, contributing to stable long-term performance.
2. Recommended Technical Parameters
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Corrosion resistance: Long-term stability in acidic environments
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Electrical conductivity: Surface resistance ≤ 20 mΩ/cm²
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Plate dimensions: Width 200–500 mm, length customizable per module
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Mesh openings: 0.5–2 mm, porosity 40–70%
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Plate thickness: 0.2–0.5 mm, mesh wire diameter 0.1–0.3 mm
These parameters can be optimized according to the electrolyzer’s power and modular design, ensuring suitability for different applications.
3. Advantages of Titanium
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High corrosion resistance: Maintains stability under strong acids or oxidative conditions
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Good electrical conductivity: Ensures uniform current distribution and improves efficiency
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Strong structural support: Can withstand high pressures and long-term cycling
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High processability: Easily cut, bent, welded, and surface-treated for various module designs
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Compatibility with precious metals: Supports deposition of iridium or platinum catalysts, enhancing overall electrolysis performance
4. Practical Applications and Case Studies
Industrial Hydrogen Production
Large PEM electrolyzers are employed in steel, chemical, and fertilizer industries for green hydrogen production. Titanium anodes and titanium mesh GDLs ensure stable operation under high temperature and high current conditions, extending equipment life to over ten years.
Renewable Energy Hydrogen Production
PEM electrolyzers powered by wind or solar energy convert renewable electricity into green hydrogen for storage. Titanium components used in electrodes and fluid-contact parts accommodate fluctuating currents and frequent start/stop operations.
Synthetic Fuel and eFuel Projects
Hydrogen produced by PEM electrolyzers can be combined with CO₂ to synthesize sustainable aviation fuel (SAF) or e-methanol. Titanium mesh GDLs help maintain uniform gas-liquid distribution, improving reaction efficiency and hydrogen purity.
High-Reliability Experimental and Demonstration Projects
In experimental or demonstration modular PEM electrolyzers, titanium is applied in small stack supports, anode plates, and cathode protection. Its high corrosion resistance and conductivity enable continuous operation for thousands of hours, validating the reliability of the process.
These examples demonstrate that titanium not only improves the performance and durability of PEM electrolyzers but also provides crucial support for the safe, stable, and sustainable development of the green hydrogen industry. By integrating titanium components strategically, electrolyzer systems can achieve higher efficiency, longer service life, and greater operational reliability